351
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[Neural cluster structure with single component prediction in multiple variable systems for X-ray fluorescence spectrometry]. GUANG PU XUE YU GUANG PU FEN XI = GUANG PU 1999; 19:426-429. [PMID: 15819081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
A neural cluster structure with single component prediction (NCSCP) was proposed for X-ray fluorescence spectrometry in a multivariable system. The neural cluster structure is built by the collection of a group of neurons which have close relationships among one another. In X-ray fluorescence analysis, the structure is constructed by choosing the elements in which there exist serious matrix effects, and deleting the components containing large noise. The predictability of the neural cluster structure was compared with that of the classical backward error propagation algorithm with single component prediction. The results show that the neural cluster structure is significantly superior to the classical algorithm in prediction accuracy, antidisturbance and the predictabilty to outliers.
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352
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Mechanisms of internalization of Staphylococcus aureus by cultured human osteoblasts. Infect Immun 1999; 67:2677-81. [PMID: 10225942 PMCID: PMC116025 DOI: 10.1128/iai.67.5.2677-2681.1999] [Citation(s) in RCA: 134] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/1998] [Accepted: 02/05/1999] [Indexed: 11/20/2022] Open
Abstract
Staphylococcus aureus is an important bone pathogen, and evidence shows that this organism is internalized by chick osteoblasts. Here we report that S. aureus is internalized by human osteoblasts. Internalization was inhibited by monodansylcadaverine and cytochalasin D and to a lesser extent by ouabain, monensin, colchicine, and nocodazole. We propose that internalization occurs via a receptor-mediated pathway, requiring the participation of cytoskeletal elements, principally actin.
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353
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A Fourier transform infrared study of the phase transition in aqueous solutions of Ethylene oxide-propylene oxide triblock copolymer. Colloid Polym Sci 1999. [DOI: 10.1007/s003960050395] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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354
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[A case-control study on the dietary risk factors of upper digestive tract cancer]. ZHONGHUA LIU XING BING XUE ZA ZHI = ZHONGHUA LIUXINGBINGXUE ZAZHI 1999; 20:95-7. [PMID: 10682542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
OBJECTIVE To understand the effect of dietary factors in Yangzhong, Jiangsu Province-a high prevalence area in China. METHODS A case-control study on 209 cases of upper digestive tract cancer was conducted. There were 68 cases of esophageal cancer, 69 cases of cardiac cancer and 72 cases of other gastric cancers including 129 males and 80 females aged 35-79 under the study. RESULTS It is revealed that intake of pickled vegetables increases the ORs of esophageal, cardiac and other gastric cancers (OR = 2.82, OR = 5.17, OR = 2.92, respectively). It is also concluded that the intake of leftovers can elevate the ORs of esophageal and cardiac gastric cancer (OR = 1.88 and OR = 1.90) and over consumption of salt also elevates the OR of cardiac cancer (OR = 1.87). However, drinking green tea may decrease the ORs of esophageal and other gastric cancers (OR = 0.20 and OR = 0.28) while fruits consumption may reduce the OR of esophageal cancers (OR = 0.51). CONCLUSION Tumors from upper digestive tract have some relations with diet factors but the effects vary with the differences of tumor sites, dose of exposure and area, etc.
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355
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Nuclear matrix targeting of the protein kinase CK2 signal as a common downstream response to androgen or growth factor stimulation of prostate cancer cells. Cancer Res 1999; 59:1146-51. [PMID: 10070976] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
Protein kinase CK2, a messenger-independent serine/threonine kinase, has been implicated in cell growth. Androgenic stimulus in rat prostate modulates its association with nuclear matrix (NM) and chromatin. Because the growth of human prostate carcinoma cells is influenced by androgens and/or growth factors, we determined the nature of CK2 signaling in the NM in response to androgen and growth factor stimuli. Androgen-sensitive LNCaP and androgen-insensitive PC-3 cells were cultured in media to regulate their growth in the presence of 5alpha-dihydrotestosterone (5alpha-DHT) or growth factors (epidermal growth factor, keratinocyte growth factor, and transforming growth factor alpha). The activity of CK2 was measured in the cytosolic and NM fractions isolated from these cells after treatment with growth stimuli. The changes in CK2 in various fractions were also confirmed by immunoblotting with a specific antibody. LNCaP cells responded to both 5alpha-DHT and growth factors for growth. The presence of these agents in the culture medium evoked a translocation of CK2 to the NM from the cytosol. The PC-3 cells did not respond to 5alpha-DHT for growth but did respond to growth factors. Under these conditions, there was also a translocation of CK2 to the NM concomitant with a decrease in the cytosolic fraction. These results suggest that CK2 translocation to the NM occurs in response to various growth stimuli in cells in culture. Thus, CK2 is a common downstream signal transducer in response to diverse growth stimuli that may relate to the pathobiology of prostate cancer cells.
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356
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[Isolating the ends of yeast artificial chromosome by inverse polymerase chain reaction]. ZHONGHUA YI XUE YI CHUAN XUE ZA ZHI = ZHONGHUA YIXUE YICHUANXUE ZAZHI = CHINESE JOURNAL OF MEDICAL GENETICS 1999; 16:44-6. [PMID: 9949241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Abstract
OBJECTIVE To establish a highly efficient method for isolating yeast artificial chromosome(YAC) ends. METHODS Based on the sequence of TAC vector, the frequent cutting enzymes were used to cleave within the vector and the genomic insert to generate relatively small fragments,which were ligated and subsequently amplified using vector primers that are in inverse orientation. The PCR products were purified and sequenced. RESULTS 8 YAC termini were isolated from YAC 776E2,964C5,11D8 and 8D1. CONCLUSION The results suggest that inverse PCR be an efficient method for isolating YAC termini.
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357
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Abstract
Antineoplastic bis-steroidal (cephalostatin-type) analogues of the saponin OSW-1 were produced from a dihydroaglycone of OSW-1. The key aglycone 6H was obtained from 5alpha-androstan-3beta-ol-17-one in 8 steps (38% yield). The SAR of the aglycones, intermediates, and hybrid analogues provide insights regarding the proposed common role of C22-oxocarbenium ions in the bioactivity of both OSW-1 and cephalostatins.
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358
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Interleukin 1 (IL-1) causes changes in lateral and rotational mobilities of IL-1 type I receptors. Biochemistry 1999; 38:1618-25. [PMID: 9931029 DOI: 10.1021/bi982068l] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
To investigate IL-1-dependent interactions of IL-1 type I (IL-1 RI) receptors on intact cells, lateral and rotational mobilities and detergent insolubility were investigated. Lateral mobility was measured by fluorescence photobleaching recovery, using a Cy3-modified, noncompetitive mAb specific for IL-1RI (M5) bound to wild-type IL-1 RI or mutant IL-1 RI with a truncated cytoplasmic tail. Addition of IL-1 causes significant reduction in the mobile fraction of wild-type IL-1 RI for two different transfected cell lines. For the mutant IL-1 RI, no significant decrease in response to IL-1 is observed, indicating that the missing cytoplasmic segment is involved in IL-1-dependent interactions of IL-1 RI that lead to reduced lateral mobility on the cell surface. The rotational mobility of IL-1 RI was assessed with phosphorescence anisotropy decay measurements using erythrosin-labeled M5. IL-1 decreases the rotational mobility of cell surface IL-1 RI on the microsecond time scale and also increases the initial anisotropy, indicating loss in segmental motion. Measurements of resistance to solubilization by Triton X-100 showed that IL-1 binding increases the fraction of IL-1 RI sedimenting with cytoskeletal residues. The IL-1 receptor antagonist protein (IL-1ra) causes partial effects in reducing rotational mobility and increasing detergent insolubility of M5-lableled IL-1 RI, indicating that this ligand causes structural changes in the presence of the dimerizing M5 mAb. These ligand-dependent physical interactions of IL-1 RI on the cell surface may be related to signal initiation by this receptor.
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359
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[Trace analysis of Zn-doped compound semiconductor material by resonant ionization mass spectrometry]. GUANG PU XUE YU GUANG PU FEN XI = GUANG PU 1999; 19:16-18. [PMID: 15818904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
An experimental setup and the procedure for the laser resonant ionization mass spectrometry (RIMS) have been described. Both an optical spectrum and a mass spectum have been shown. The detection limit that can be reached by using this procedure has been estimated.
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360
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Conformational Structure of Triblock Copolymers by FT-Raman and FTIR Spectroscopy. J Colloid Interface Sci 1999; 209:368-373. [PMID: 9885264 DOI: 10.1006/jcis.1998.5897] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Fourier transform Raman (FT-Raman) and Fourier transform infrared (FTIR) spectra of poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (PEO-PPO-PEO) triblock copolymers as pure solids or liquids and in aqueous solutions have been examined. The qualitative features in Raman and FTIR spectra of these copolymers have been presented. The Raman and FTIR spectra of PEO-PPO-PEO triblock copolymers are very sensitive to the structural and conformational changes. It shows that the relative intensities of several peaks in Raman spectra are dependent on the PPO/PEO ratios and the conformation of the copolymers. From Raman and FTIR spectra, Pluronic F68 and F88 assume helical structures with a few trans conformers. Other block copolymers exhibit that the disordered structure increases with increasing PPO/PEO ratio. Comparison of Raman spectra of PEO-PPO-PEO triblock copolymers as pure solids or liquids with those in aqueous solutions has been presented. Copyright 1999 Academic Press.
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361
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155 The DNA damage sensing pathways regulating dephosphorylation of histone H1 and H3 diverge upstream of ATM. Int J Radiat Oncol Biol Phys 1999. [DOI: 10.1016/s0360-3016(99)90173-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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362
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Role of protein kinase CK2 in phosphorylation nucleosomal proteins in relation to transcriptional activity. Mol Cell Biochem 1999; 191:135-42. [PMID: 10094402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
Protein kinase CK2 undergoes rapid translocation to nuclear matrix and nucleosomes on androgenic stimulation of growth in prostatic epithelial cells. Further, CK2 appears to be regulated differentially in the transcriptionally active and inactive nucleosomes. We have investigated the role of CK2 in phosphorylation of nucleosome-associated proteins in the transcriptionally active and inactive nucleosomes that were isolated from ventral prostate subjected to different androgenic status in vivo. Proteins associated with these nucleosomes were phosphorylated via the intrinsic protein kinase activity, using [gamma-32P]ATP in the absence and presence of GTP. Several proteins appear to be potential substrates for CK2 associated with the nucleosomes. Among them are proteins that are differentially associated with the transcriptionally active and inactive nucleosomes. Phosphorylation of several of these proteins is modulated depending not only on their sites of association (i.e., active vs. inactive nucleosomes) but also on the state of transcriptional activity. Differential phosphorylation of specific proteins by CK2 associated with the active and inactive nucleosomes may be pertinent to the process of transcription regulation.
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363
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[Carcinoma of the lips developing in discoid lupus erythematosus]. ZHONGHUA KOU QIANG YI XUE ZA ZHI = ZHONGHUA KOUQIANG YIXUE ZAZHI = CHINESE JOURNAL OF STOMATOLOGY 1999; 34:13-5. [PMID: 11776525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
OBJECTIVE This clinical study was designed to learn the diagnosis and treatment of lip carcinoma developing in discoid lupus erythematosus. METHODS One hundred and eighty-one of squamous cell carcinoma of the lips treated in our department from 1980 to 1995 were retrospectively studied. RESULTS Ten cases of the 181 lip carcinoma (5.5%) had concomitant discoid lupus erythematosus (DLE) of the vermilion border of the lower lip. CONCLUSION Bleomycin or radiotherapy is the best treatment for the disease.
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364
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[A preliminary study on the relationship between nutritional status and postoperative complications in patients with head and neck malignancies]. ZHONGHUA ER BI YAN HOU KE ZA ZHI 1998; 33:368-70. [PMID: 11938853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/18/2023]
Abstract
OBJECTIVES To study the role of nutritional factor in the development of postoperative complications in patients with head and neck malignancies. METHODS Postoperative complications of 96 patients with head and neck malignancies who were operated on were surveyed. Twenty-seven developed postoperative complications; the remaining 69 went uneventful. Comparisons of nutritional status and clinical variables between these two groups were made. RESULTS 1. The prevalence of poor preoperative nutritional status in the complication group (56%) was higher as compared with that in the noncomplication group (20%) (P < 0.001); 2. values of body weight, triceps skin fold thickness, arm circumference, arm muscle circumference, and creatinine-height index in the complication group decreased much more significantly than in the noncomplication group (P < 0.001); 3. the nitrogen and calorie intake within the first postoperative week was lower in the complication group than in the non-complication group (P < 0.001). CONCLUSIONS Nutritional factor plays a very important role in the development of postoperative complication and the perioperative nutritional support for head and neck surgical patients should not be ignored.
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365
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Fabric contamination from pesticides on tractor tires. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 1998; 61:677-683. [PMID: 9841730 DOI: 10.1007/s001289900814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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366
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Differential stimulation of proline-rich tyrosine kinase 2 and mitogen-activated protein kinase by sphingosine 1-phosphate. EUROPEAN JOURNAL OF BIOCHEMISTRY 1998; 257:403-8. [PMID: 9826186 DOI: 10.1046/j.1432-1327.1998.2570403.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Sphingosine 1-phosphate (SphP), a metabolite of cellular sphingolipids, has been shown to induce cell proliferation by activating the mitogen-activated protein kinase (MAPK) pathway. Proline-rich tyrosine kinase 2 (Pyk2) is a novel cytosolic tyrosine kinase which mediates activation of the MAPK or c-Jun N-terminal kinase (JNK) signaling pathways in response to a variety of stimuli that elevate intracellular calcium. In this report, we show that SphP stimulates both tyrosine phosphorylation of Pyk2 and MAPK activation in a transient and dose-dependent manner in rat aortic smooth muscle cells. Further studies indicate that Pyk2 phosphorylation, but not MAPK activation, is dependent on a pertussis toxin-sensitive G-protein-coupled receptor as well as partially on actin cytoskeleton. In addition, both intracellular calcium mobilization and protein kinase C (PKC) are required for optimal Pyk2 phosphorylation while either calcium increase or PKC activation is sufficient for MAPK activation in response to SphP. Finally, we show that a tyrosine kinase(s) other than Pyk2 is necessary for MAPK activation by SphP. Together, these results suggest that SphP stimulates tyrosine phosphorylation of Pyk2 through a G-protein coupled receptor, which is dissociated from its activation of the MAPK pathway in these cells.
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367
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[Genetic analysis of varicose vein of lower extremities]. ZHONGHUA YI XUE YI CHUAN XUE ZA ZHI = ZHONGHUA YIXUE YICHUANXUE ZAZHI = CHINESE JOURNAL OF MEDICAL GENETICS 1998; 15:221-3. [PMID: 9691130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
OBJECTIVE To make a hereditary analysis of varicose vein of lower extremities(VVLE), including hereditary pattern, sex ratio and the transmitted expression male and female of varicose vein of lower extremities. METHODS The ascertainment probability was estimated according to Weinberg's proband method. The value of segregation ratio P and proportion of sporadic cases X were estimated by the maximum likelihood score method. The calculations were performed using computer program of segregation analysis. The VVLE cases were random samples from inpatients and outpatients of the authors' hospital from 1991 to 1996. RESULTS There were 68 pedigrees including 80 nuclear families in 3 different mating types:UAU, UAA and AAA. UAU, UAA and AAA were analysed together. UAA and UAU (multiplex families) were analysed respectively. All the values were compatible with autosomal dominant inheritance of incomplete penetrance; the penetrance frequencies were 91.94%, 78.14% and 69. 92% respectively. The proportion of X was 24.32%. The UAU was compatible with autosomal recessive inheritance; the proportion of sporadic cases was 36.75%. CONCLUSION VVLE is compatible with autosomal dominant and recessive inheritance. The sex ratio of male:female is 2.39:1. The transmission is possible from male and female to male and female both.
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368
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[Effect of dietary calcium on serum calcium and calmodulin activity of brain and hypothalamus in rats]. WEI SHENG YAN JIU = JOURNAL OF HYGIENE RESEARCH 1998; 27:253-5. [PMID: 10682597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
The effect of low calcium (LC) diet supplemented with various amount of calcium on serum calcium and calmodulin of rats was studied. The LC diet was mainly composed of corn low in calcium. The calcium content of LC diet was only half of that of the stock diet. Seventy Wistar rats were divided into 7 groups by weight and sex. Results showed that serum calcium in LC group was low and calmodulin activity was also low. These parameters were improved while calcium was supplemented in LC diet. There is a significant dose-response relationship among diet calcium, serum calcium and growth. When the total calcium in diet was increased up to 1000 mg/kg, serum calcium level was closed to that of normal and higher than the serum calcium in LC group significantly. The study demonstrated that low dietary calcium, hypocalcemia and low calmodulin are associated. When total dietary calcium was up to 1000 mg/kg, the growth retardation was attenuated.
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369
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[New challenge to communicable diseases and their immunological prevention at present]. ZHONGHUA YU FANG YI XUE ZA ZHI [CHINESE JOURNAL OF PREVENTIVE MEDICINE] 1998; 32:198-200. [PMID: 10322754] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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370
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[An experimental study on promoting reconstruction of microcirculation of the ischemic skin flap with basic fibroblast growth factor]. ZHONGHUA ZHENG XING SHAO SHANG WAI KE ZA ZHI = ZHONGHUA ZHENG XING SHAO SHANG WAIKF [I.E. WAIKE] ZAZHI = CHINESE JOURNAL OF PLASTIC SURGERY AND BURNS 1998; 14:286-9. [PMID: 10680496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
OBJECTIVE This study was to determine whether the basic fibroblast growth factor (bFGF) could promote reconstruction of microcirculation in the ischemic portion of a random skin flap. METHODS Five methods were used in the experiment: measurement of the survival area of the skin flap; light and electron microscopic studies; immunohistochemical observation of the endothelial cell and microvessel image analysis technology (IAT). RESULT The survival area and microvessels in the skin flap were significantly increased in the treated group. The results indicate that bFGF can stimulate the proliferation and differentiation of endothelial cells in vivo and promote the microcirculation of the ischemic flap. CONCLUSION bFGF could promote reconstruction of microcirculation of the ischemic skin flap.
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371
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Dynamics of protein kinase CK2 association with nucleosomes in relation to transcriptional activity. J Biol Chem 1998; 273:13675-80. [PMID: 9593708 DOI: 10.1074/jbc.273.22.13675] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Protein kinase CK2 has been implicated in control of cell growth and proliferation. Since growth stimuli evoke its preferential association with chromatin and nuclear matrix, we examined the dynamics of CK2 in nucleosomes fractionated on the basis of their transcriptional activity in the rat prostate. In this model, androgens induce expression of androgen-dependent genes but inhibit the androgen-repressed genes, whereas absence of androgens has the reverse effect. The level of CK2 was higher in the active than in inactive nucleosomes from normal prostate. Differential alterations in the levels of CK2 activity in the transcriptionally active versus inactive nucleosomes were evoked by androgen deprivation or administration. Comparison of the distribution of CK2 in active and inactive nucleosomes under varying androgenic conditions showed that the relative CK2 activity intrinsic to the transcriptionally active nucleosomes remained fairly stable, concordant with gene activity specific to the androgenic status. However, CK2 associated with inactive nucleosomes declined to a minimal level on androgen deprivation but increased rapidly on androgen administration (reflecting expression of multiple androgen-dependent genes). We suggest a role for CK2 in promoting the conformational transition of inactive nucleosomes to the active form and in the function of transcriptionally active nucleosomes.
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372
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[Polymorphism analysis of 4 loci of X-chromosome in a Chinese population of the Han nationality]. ZHONGHUA YI XUE YI CHUAN XUE ZA ZHI = ZHONGHUA YIXUE YICHUANXUE ZAZHI = CHINESE JOURNAL OF MEDICAL GENETICS 1998; 15:92-4. [PMID: 9531648] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVE To investigate the polymorphism of 4 loci of X-chromosome in the Hans. METHODS Using PCR-SSLP, the authors analysed the polymorphism of DXS1068, DXS7132, DXS6804 and DXS6799 in the X-chromosome in 70 randomly selected female Hans. RESULTS The number of alleles in the 4 loci were 5,5,5 and 6 respectively; there were no significant differences between the observed and estimated and genotype probabilities of the 4 loci; the estimates of heterozygosity of 4 loci were 0.6819, 0.6895, 0.7659 and 0.6483 respectively and there were no significant differences between the observed and estimated heterozygosity of the 4 loci. CONCLUSION The distribution of alleles and genotype probabilities of 4 loci all observe the Hardy-Weinberg equilibrium.
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373
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[Determination of adenosine and 3'-deoxyadenosine in Cordyceps militaris (L.) Link. by HPLC]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 1998; 23:236-7, 256. [PMID: 11596253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
The establishment of a quantitative determination method by HPLC for adenosine and 3'-deoxyadenosine in Cordyceps militaris is reported. The sample was extracted with water under ultrasonic management for 2 hours. Chromatographic conditions: YWG C18 10 microns 5 mm x 200 mm; mobile phase consisted of NaH2PO4-NaOH buffer solution (pH 6.8); UV detection at 260 nm. The recoveries of adenosine and 3'-deoxyadenosine were 95.8% +/- 0.64% and 100.6% +/- 0.65% (n = 5) respectively.
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374
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[A study of genetic patterns of idiopathic epilepsy]. ZHONGHUA YI XUE YI CHUAN XUE ZA ZHI = ZHONGHUA YIXUE YICHUANXUE ZAZHI = CHINESE JOURNAL OF MEDICAL GENETICS 1998; 15:38-41. [PMID: 9456370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
OBJECTIVE To explore genetic patterns of idiopathic epilepsy (IEP). METHODS Using familial analysis, tests for multifactorial inheritance and segregation analysis, we studied 210 pedigrees with IEP found in a population survey in Shangdong province. RESULTS The genetic pattern of IEP is not polygenic but is mainly influenced by autosomal recessive disorders. The results of segregation analysis indicate that the genetic pattern of U*U multiplex families and U*A group is autosomal recessive. Only a few cases in U*U group may accept the assumption of autosomal recessive inheritance while the other are sporadic cases. The frequency of sporadic cases is approximately 78.5%. Genetic heterogeneity may influence U*U(f) group and U*U group. CONCLUSION Further and careful empirical scrutiny of U*U(f) group and the sporadic cases in U*U group offers the best hope for getting a clear understanding of genetic patterns and mechanisms in IEP.
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375
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Relationship between lung function and blood pressure in Chinese men and women of Beijing and Guangzhou. PRC-USA Cardiovascular and Cardiopulmonary Epidemiology Research Group. Int J Epidemiol 1998; 27:49-56. [PMID: 9563693 DOI: 10.1093/ije/27.1.49] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Previous studies of western populations have shown an inverse association between lung function and blood pressure. METHODS As part of a People's Republic of China-United States cardiopulmonary epidemiology study, we investigated the cross-sectional relationship between lung function and blood pressure in 6757 Chinese men and women, aged 35-54, from Beijing and Guangzhou, China. We also evaluated the longitudinal association between lung function and incident hypertension among 4818 initially normotensive subjects followed up between 2 and 4 years later. RESULTS In our cross-sectional analyses of baseline data, lung function varied inversely with baseline systolic (SBP) and diastolic blood pressure (DBP) in all women and in Beijing men. This association held for absolute and height-standardized forced vital capacity (FVC) and one-second forced expiratory volume (FEV1) (correlations: 0.10, -0.18, P < 0.0001), but was weaker after adjustment for age (correlations: -0.02, -0.11). The longitudinal follow-up showed that lower initial lung function levels were associated with a higher incidence of hypertension (SBP > or = 140 mmHg or DBP > or = 90 mmHg or currently using antihypertensive medications), but only among women in Guangzhou. Relative risks for hypertension incidence for those in the two lowest quintiles for FEV1 and FVC, compared to those in the two highest quintiles, ranged from 1.9 to 2.3 for Guangzhou women and from 0.9 to 1.4 for all other gender-city subgroups. Logistic regression analyses adjusting for age, baseline SBP, body mass index, smoking, education, and urban versus rural setting generally confirmed these patterns. CONCLUSIONS These results suggest a statistically significant, though weak, inverse relationship between lung function and blood pressure in Chinese men and women. This association is largely attributable to age and is present prospectively only in women.
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376
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Differential regulation of Pyk2 and focal adhesion kinase (FAK). The C-terminal domain of FAK confers response to cell adhesion. J Biol Chem 1998; 273:2384-9. [PMID: 9442086 DOI: 10.1074/jbc.273.4.2384] [Citation(s) in RCA: 117] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Pyk2 is a recently described cytoplasmic tyrosine kinase that is related to focal adhesion kinase (FAK) and can be activated by a variety of stimuli that elevate intracellular calcium. In this report, we showed that Pyk2 and FAK tyrosine phosphorylation are regulated differentially by integrin-mediated cell adhesion and soluble factors both in rat aortic smooth muscle cells, which express endogenous Pyk2 and FAK, and in transfected Chinese hamster ovary cells. We also found that Pyk2 is diffusely present throughout the cytoplasm, while FAK is localized in focal contacts as expected, suggesting that the different localization may account for their differential regulation. By analyzing a chimeric protein contain N-terminal and kinase domains of Pyk2 and C-terminal domain of FAK, we provided evidence that the distinctive C-terminal domains of Pyk2 and FAK were responsible for their differential regulation by integrins and soluble stimuli as well as their subcellular localization. Finally, we correlated FAK, Pyk2, and the chimeric protein binding to talin, but not paxillin, with their regulation by integrins and focal contact localization. These results demonstrate that the distinctive C-terminal domain of Pyk2 and FAK confer their differential regulation by different subcellular localization and association with the cytoskeletal protein talin.
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377
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Abstract
Ninety-one cases of adenoid cystic carcinoma (ACC) of the salivary glands with more than ten years' follow up were studied to investigate factors influencing the survival rate of patients, which vary according to site, histological type, clinical stage and nature of therapy. The data were statistically analysed for survival curves. Log rank tests were employed to assess the statistical significance of various groups. As a result, it may be concluded that tumour site, clinical stage and histological type are the important factors influencing the prognosis. ACC of the palate and parotid, early clinical stage, glandular/tubular histological type, and tumour without nerve involvement had the best prognosis. ACC in the submandibular gland, maxillary antrum and tongue, advanced clinical stage (stage III and IV), solid histological type, and tumour with nerve involvement had a poor prognosis.
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378
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Hybridization Analysis of Microbial DNA from Fuel Oil-Contaminated and Noncontaminated Soil. MICROBIAL ECOLOGY 1997; 34:178-187. [PMID: 9337413 DOI: 10.1007/s002489900047] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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379
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[Cellular immunity in childhood iron deficiency anemia with recurrent respiratory infections]. ZHONGHUA XUE YE XUE ZA ZHI = ZHONGHUA XUEYEXUE ZAZHI 1997; 18:566-7. [PMID: 15625892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/01/2023]
Abstract
OBJECTIVE To examine interleukin-2 (IL-2) activity,serum soluble IL-2 receptor (sIL-2R) level and T lymphocyte subsets in peripheral blood from 63 childhood iron deficiency anemia (IDA) patients with recurrent respiratory infections(RRI). METHODS IL-2 activity, sIL-2R level and T lymphocyte subsets were assayed by MTT, ELISA and APAAP, respectively. RESULTS IL-2 activity, percentages of CD3+ and CD4+ cells as well as the ratio of CD4+/ CD8+ cells in the patients were significantly lower ( P < 0.01),while sIL-2R levels were higher than that in normal controls (P < 0.01). No significant change was found in the percentage of CD8+ cells. CONCLUSION Cellular immunity was impaired in childhood IDA with RRI.
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380
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Abstract
Combined subjective and objective nutritional assessment was performed on admission in 127 patients with oral and maxillofacial malignancies. On the basis of the nutritional assessment result, three typical nutritional parameters-body weight (BW) (X1), mid-upper-arm circumference (MAC) (X2), and hand grip strength (HGS) (X3) were used to establish a new nutritional assessment method that was developed by a computer-based discriminant analysis. The established model was as follows: Y1 = -126 + 1.09X1 + 1.34X2 + 0.23X3; Y2 = -95.63 + 0.96X1 + 1.17X2 + 0.19X3. In the model Y1 was regarded as good nutrition and Y2 as malnutrition. The larger value of Y stood for the patient's nutritional status (i.e. Y1 > Y2, well nourished; Y1 < Y2 malnourished). The new nutritional assessment correlates well with the combined subjective and objective nutritional assessment with a total agreement rate of 88.2%. With its simplicity and accuracy, the new nutritional assessment deserves a wide application in clinical situation.
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381
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[Biological function and clinical use of fibroblast growth factors]. ZHONGGUO XIU FU CHONG JIAN WAI KE ZA ZHI = ZHONGGUO XIUFU CHONGJIAN WAIKE ZAZHI = CHINESE JOURNAL OF REPARATIVE AND RECONSTRUCTIVE SURGERY 1997; 11:272-5. [PMID: 9867927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
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382
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Granular terbufos exposure and cleanup of glove materials. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 1997; 59:187-193. [PMID: 9211687 DOI: 10.1007/s001289900463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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383
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[Epidemic trend of tuberculous meningitis in children of Heilongjiang province]. ZHONGHUA JIE HE HE HU XI ZA ZHI = ZHONGHUA JIEHE HE HUXI ZAZHI = CHINESE JOURNAL OF TUBERCULOSIS AND RESPIRATORY DISEASES 1997; 20:167-8. [PMID: 10072823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
OBJECTIVE To investigate the epidemic trend of tuberculous meningitis in children of Heilongjiang province in recent ten years, and to provide scientific evidence for control of the disease. METHODS The data, registered by 82 counties' antituberculosis institute, of tuberculous meningitis patients under 14 years were analyzed, and the epidemic trend of the disease was also discussed. RESULTS The incidence of tuberculous meningitis was 9.58 per 10,0000 populations in 1982, 2.17 per 10,0000 populations in 1992. The rate of annual decrease was 13.8%. CONCLUSION Participation of the government, improvement of pelple's life standard, control of sources of infection, and vaccination of BCG are effective measures for decreasing the incidence of this disease.
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384
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Abstract
In this study, the plasma fibronectin was evaluated as a nutritional marker in protein- and protein-energy malnourished rats in comparison with plasma prealbumin, albumin, and total protein. The plasma fibronectin was determined by nephelometric assay based on the interaction of an antigen and antibody. The rats were subjected to three diets, containing 20, 5, and 0% casein, respectively, for 5 wk except in the last 2 wk, the rats on the 0% casein diet were re-fed on a 20% casein diet. The results showed that in the rats on a 5% casein diet (protein malnourished), the plasma fibronectin concentration rose significantly in the early stage and normalized thereafter. In the rats subjected to a 0% casein diet (protein-energy malnourished), the plasma fibronectin concentration did not decline quickly in response to protein depletion, compared with the plasma prealbumin, albumin, and total protein concentrations. Following the re-feeding of a 20% casein diet in the last 2 wk, the plasma fibronectin concentration was restored earlier than other plasma protein concentrations. No significant change in plasma fibronectin concentration was found in the rats receiving a 20% casein diet (control) over the 5 wk feeding period. It is concluded that plasma fibronectin may not be a suitable marker for protein or protein-energy malnutrition, though it is a sensitive index for nutritional rehabilitation.
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385
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[Production of anti-enteric adenovirus monoclonal antibody by electrofusion and semi-solid medium culture]. ZHONGHUA SHI YAN HE LIN CHUANG BING DU XUE ZA ZHI = ZHONGHUA SHIYAN HE LINCHUANG BINGDUXUE ZAZHI = CHINESE JOURNAL OF EXPERIMENTAL AND CLINICAL VIROLOGY 1997; 11:69-71. [PMID: 15619911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/01/2023]
Abstract
Ten million splenocytes from the enteric adenovirus (Ad40/41) immunized mice were fused with 3 x 10(6) myeloma cells by electrofusion. Then, the cells were selectively cultured in methyl cellulose semi-solid medium. Eighteen clones of hybridoma were directely picked out from the culture plates and 7 of them could secret high level specific antibodies to enteric adenovirus. So far, the anti-Ad40/41 virus monoclonal antibodies were successfully generated by the protocal of electrofusion accompanied with selective culture in methyl cellulose semi-solid medium.
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386
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Temporal difference learning applied to sequential detection. IEEE TRANSACTIONS ON NEURAL NETWORKS 1997; 8:278-87. [PMID: 18255632 DOI: 10.1109/72.557666] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
This paper proposes a novel neural-network method for sequential detection, We first examine the optimal parametric sequential probability ratio test (SPRT) and make a simple equivalent transformation of the SPRT that makes it suitable for neural-network architectures. We then discuss how neural networks can learn the SPRT decision functions from observation data and labels. Conventional supervised learning algorithms have difficulties handling the variable length observation sequences, but a reinforcement learning algorithm, the temporal difference (TD) learning algorithm works ideally in training the neural network. The entire neural network is composed of context units followed by a feedforward neural network. The context units are necessary to store dynamic information that is needed to make good decisions. For an appropriate neural-network architecture, trained with independent and identically distributed (iid) observations by the TD learning algorithm, we show that the neural-network sequential detector can closely approximate the optimal SPRT with similar performance. The neural-network sequential detector has the additional advantage that it is a nonparametric detector that does not require probability density functions. Simulations demonstrated on iid Gaussian data show that the neural network and the SPRT have similar performance.
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387
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Clinical observation on efficacy of electro-acupuncture therapy in hyperplasia of mammary glands and its effect on immunological function. J TRADIT CHIN MED 1996; 16:281-7. [PMID: 9389105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Based on our work on electro-acupuncture therapy of hyperplasia of mammary glands and in order to observe further the relationship between immunological function and E2 in hyperplasia of mammary glands, we determined the change not only in immunological function before and after electro-acupuncture in 44 in-patients with hyperplasia of mammary glands and having the same menstruation date, but also in electro-acupuncture treated rat hyperplasia of mammary glands model. We found that there was decrease of immunological function in hyperplasia of mammary glands and this function could be remarkably enhanced by electro-acupuncture both in hyperplasia of mammary glands patients and in rat hyperplasia of mammary glands model. The mechanism implies it might be that the inhibitory effect on immunological function exerted by high concentration of E2 was lowered by electro-acupuncture, hence the immunological function was reinforced. The results of this study are important in exploration of both the pathogenesis of this disease and the mechanism of electro-acupuncture, and in reducing the incidence of breast carcinoma.
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388
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[Comparisons of three simple nutritional assessments applied to patients with oral and maxillofacial malignancies]. ZHONGHUA KOU QIANG YI XUE ZA ZHI = ZHONGHUA KOUQIANG YIXUE ZAZHI = CHINESE JOURNAL OF STOMATOLOGY 1996; 31:378-80. [PMID: 9592299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Combined subjective and objective nutritional assessment (SNA), concise nutritional assessment (CNA), general nutritional status score (GNS), and subjective global assessment of nutritional status (SGA) were applied to assess the nutritional status of 127 patients with oral and maxillofacial malignancies. On this base SNA was used as a standard nutritional assessment to compare the validities of CNA, GNS, and SGA. The results showed: 1) the total agreement rate of CNA (88.2%) was higher than that of GNS (78.0%) and SGA (78.7%); 2) the false positive rate (9.9%) and false negative rate (15.2%) of CNA was lower than that of GNS (17.3%, 30.4%) and SGA (14.8%, 32.6%); 3) the diagnosis index of CNA (74.9%) was significantly (P < 0.05) higher than that of GNS (52.3%) and SGA (52.6%); and 4) the nutritional parameters of CNA were measured by instruments with little man-made errors. These results indicate that CNA can be regarded as the best nutritional assessment for the patients in oral and maxillofacial surgery.
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389
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[Gestational diabetes]. ZHONGHUA FU CHAN KE ZA ZHI 1996; 31:636-9. [PMID: 9275463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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390
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Kinship and familiarity as factors affecting social transfer of food preferences in adult Mongolian gerbils (Meriones unguiculatus). J Comp Psychol 1996; 110:243-51. [PMID: 8858846 DOI: 10.1037/0735-7036.110.3.243] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Experiments were carried out with Mongolian gerbils (Meriones unguiculatus) to assess whether a socially mediated acquisition of diet selection exists in this species. Results showed that a gerbil was influenced in its diet choices by information extracted during a brief period of interaction with a familiar conspecific that had recently eaten a novel food. Data revealed that the acquisition of a food preference from a conspecific depends on the existence of a social bond between the interacting gerbils. Either genetic relatedness (being brother or sister raised in different litters) or familiarity (being bred in the same litter or being member of a reproductive pair) is necessary for the transfer of information. Unfamiliar and unrelated observer gerbils did not selectively choose their demonstrator's food.
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391
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Radiofrequency ablation to cure atrial fibrillation: mechanisms and strategies. Chin Med J (Engl) 1996; 109:648-53. [PMID: 9206070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
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392
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Abstract
We have constructed a detailed map of the genomic region containing the ETS-variant gene 6 (ETV6), involved in translocations and deletions associated with hematologic malignancies. Thirty-eight cosmids were characterized belonging to two contigs spanning 340 kb, and an EcoRl restriction map was developed. The gap between the two contigs, 2 kb in size, was closed by PCR. The contigs contain the complete coding sequence and the 5' and 3' UTRs of ETV6. Eight exons accounting for the ETV6 cDNA sequence were identified. The helix-loop-helix (HLH) motif is coded by exons 3 and 4, whereas exons 6-8 code for the ETS DNA-binding domain. All introns show consensus 5' donor and 3' acceptor splice sites. Introns 1 and 2 span 100 and 82 kb, respectively, and introns 3-7 range from 15 to 1.3 kb. An alternative exon 1 (exon 1B) is localized in intron 2. The 5' end of the ETV6 gene is associated with a CpG island characterized by the presence of four Notl, four Sacll, and three BssHll recognition sites and several SP1- and AP2-binding motifs. Alternative polyadenylation at the 3' end of the ETV6 gene generates the three transcripts of 6200, 4300, and 2400 nucleotides, respectively. The ETV6 gene spans 240 kb and is flanked at its 5' and 3' end by D12S1697 and D12S98, respectively. The markers D12S1095 and D12S89 are located in the first intron. Two new DNA polymorphisms were identified in the ETV6 gene, which will be useful for the analysis of loss of heterozygosity reported for the ETV6 gene in leukemia.
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393
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The 12;21 translocation involving TEL and deletion of the other TEL allele: two frequently associated alterations found in childhood acute lymphoblastic leukemia. Blood 1996; 87:2891-9. [PMID: 8639909] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
A recurrent t(12;21)(p13;q22) has recently been described in human acute lymphoblastic leukemias (ALLs). This translocation fuses TEL and AML1, two genes previously cloned from translocation breakpoints in myeloid leukemias. In addition, allelic loss of the TEL gene can be detected in 15% to 22% of childhood ALLs. In the present study, we have sought allelic deletions of TEL and the presence of the t(12;21) in 50 children with B-lineage ALL, using a combination of microsatellite typing, fluorescent in situ hybridization (FISH), and analysis of the fusion transcripts resulting from the TEL-AML1 gene fusion. Our results indicate that the association between the t(12;21) and the deletion of the nontranslocated allele of TEL is among the most frequent abnormalities observed in B-lineage ALLs. FISH analysis using several cosmid probes showed that, in one patient with a t(12;21) translocation involving TEL, the second allele had an intragenic deletion. This observation points to TEL as the actual target of 12p12-13 deletions in patients that associate a t(12;21) with a deletion. The TEL-AML1 fusion RNA was found in all patients with the t(12;21) whereas the reciprocal AML1-TEL transcript was only found in a subset of patients, suggesting that only the protein product encoded by TEL-AML1 is likely to play a role in leukemogenesis. The observation that, in two patients with the t(12;21), a deletion of TEL was only present in a subclone indicates that this deletion was a secondary event that occurred after the translocation. The frequent occurrence of TEL deletions in patients with t(12;21) suggests that the deletion of the normal TEL allele subsequent to the t(12;21) provides a further proliferative advantage to leukemic cells.
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394
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Abstract
Distributions of the heat flux to the workpiece and the convection heat transfer coefficient on the workpiece surface during straight surface grinding are estimated from measured temperatures in the workpiece subsurface using inverse heat transfer methods developed in Part 1. The results indicate that the heat flux to the workpiece is distributed approximately linearly (triangular heat source) along the grinding zone with about 70 to 75 percent of the total energy transported as heat to the workpiece for grinding of steels with a conventional aluminum oxide wheel and only about 20 percent with CBN superabrasive wheels. The wheel-workpiece contact length corresponding to the region of positive heat flux to the workpiece is found to be generally close to but slightly longer than the theoretical geometric contact length. The convection heat transfer coefficient for cooling by the applied grinding fluid is greatest just behind the trailing edge of the grinding zone where fluid is directly applied, and negligible ahead of the grinding zone.
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395
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Abstract
Thermal analyses of the grinding process generally require assumptions concerning the distributions of the heat flux to the workpiece within the grinding zone and convective cooling outside the grinding zone. The present work is concerned with the use of inverse heat transfer methods to estimate the heat flux and convection heat transfer coefficient distributions on the workpiece surface during straight surface grinding from temperature measurements within the workpiece. In the present paper, three inverse heat transfer methods are developed: temperature matching, integral, and sequential methods. Each method is evaluated for accuracy and stability using simulated temperature data. The selection of the sampling frequency of the temperature measurements and location of the temperature sensor are found to be critical for both estimation accuracy and stability. In a second paper, these inverse heat transfer methods are applied to estimate the distributions of the heat flux and convection heat transfer coefficients on the workpiece surface for grinding of steels with aluminum oxide and CBN abrasive wheels.
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396
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Fluorescence resonance energy transfer reveals interleukin (IL)-1-dependent aggregation of IL-1 type I receptors that correlates with receptor activation. J Biol Chem 1995; 270:27562-8. [PMID: 7499217 DOI: 10.1074/jbc.270.46.27562] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Fluorescence resonance energy transfer (FRET) was used to investigate whether interleukin-1 (IL-1) causes the aggregation of IL-1 type I receptors (IL-1 RI) at the cell surface. For these experiments, a noncompetitive anti-IL1 RI monoclonal antibody, M5, was labeled separately with a donor probe, fluorescein isothiocyanate, or with an acceptor carbocyanine probe, Cy3. Donor-labeled M5 and acceptor-labeled M5 were simultaneously bound to transfected mouse IL-1 RI on either C-127 mouse mammary carcinoma cells or on Chinese hamster ovary (CHO)-K1 cells, and the ratio of acceptor emission at 590 nm to donor emission at 525 nm (excitation at 488 and 514 nm) was monitored with flow cytometry as an indicator of FRET. Addition of a saturating concentration of human IL-1 alpha at 22 degrees C causes a time-dependent increase in FRET for both cell lines that indicates IL-1-dependent self-association of IL-1 RI. Binding of the IL-1 receptor antagonist at 22 degrees C causes little or no FRET for both cell lines, indicating a correlation between receptor aggregation and the ability of the ligand to stimulate a functional response. When donor-labeled and acceptor-labeled Fab fragments of M5 are used to monitor FRET, IL-1 alpha causes efficient energy transfer in the CHO-K1 cells at 22 degrees C, but not at 4 degrees C. In contrast, IL-1 alpha causes much less FRET at 22 degrees C in C-127 cells when the M5 Fab fragments are used instead of the intact bivalent M5. In a striking parallel, IL-1 alpha-dependent activation of prostaglandin E2 production depends on the bivalent M5 antibody in the C-127 cells, but is independent of this monoclonal antibody in the CHO-K1 cells. These results provide a strong correlation between the ability of IL-1 to cause the aggregation of IL-1 RI and the stimulation of a functional response.
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397
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Abstract
Temperatures generated in the workpiece during straight surface plunge grinding follow a transient behavior as the grinding wheel engages with and disengages from the workpiece, and throughout the entire grinding pass for workpieces which are shorter than needed to reach a quasi-steady state condition. In the present paper, a thermal model is developed for the transient temperature distribution under regular and creep-feed grinding conditions. Numerical results obtained using a finite difference method indicate that the workpiece temperature rises rapidly during initial wheel-workpiece engagement (cut in), subsequently reaches a quasi-steady state value if the workpiece is sufficiently long, and increases still further during final wheel-workpiece disengagement (cut out) as workpiece material is suddenly unavailable to dissipate heat. Cooling by a nozzle directed at the end face of the workpiece should significantly reduce the temperature rise during cut out.
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398
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Abstract
The sequence of a splice variant of the rat mineralocorticoid receptor (MR) gene is presented. A cDNA clone corresponding to rat MR was isolated from a rat brain cDNA library. Sequence analysis of the region corresponding to the DNA binding domain revealed the presence of a 12 base pair (bp) insertion. Analysis of mRNA from several rat tissues suggests that the variant is less abundant than the wild type in most tissues. The insertion variant is also a product of the human MR gene, the identical splice variant was also observed in human white blood cell mRNA. Unlike other splice variants reported for the MR, this variant alters the encoded protein by the addition of four amino acid residues in the DNA binding domain. The altered protein may influence the affinity of the MR for mineralocorticoid or glucocorticoid response elements.
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399
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Lack of association between HLA class II polymorphisms and essential hypertension in a Belgian population. J Hum Hypertens 1995; 9:553-5. [PMID: 7562884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The aim of the present study was to investigate whether the HLA class II polymorphisms contributes to the susceptibility to essential hypertension in the Belgian population. For this purpose we studied 120 hypertensive patients and 168 normotensive controls by means of a PCR-SSO assay. No significant difference in allele and genotype frequencies of the DRB and DPB1 loci could be found between the two groups. We concluded that essential hypertension as a multifactorial and heterogeneous disease cannot be associated with one of the HLA class II DRB and DPB1 alleles in Belgian patients.
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400
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[Comparison of toxic effects of brucite and aluminium-treated chrysotile on macrophage]. ZHONGHUA YU FANG YI XUE ZA ZHI [CHINESE JOURNAL OF PREVENTIVE MEDICINE] 1995; 29:219-21. [PMID: 7587662] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Toxicity of brucite and two kinds of chrysotile (Xinkang and Sichuan chrysotile) treated with aluminium chloride to alveolar macrophage from guinea pigs was compared in vitro. Results showed changes of toxicity, indicated as generation of O2-., increase in membrane lipid fluidity and leakage of intracellular potassium, etc., caused by aluminium-treated chrysotile, were significantly lower than those by bructite of same dose (P < 0.05 and P < 0.01, respectively), and changes of other toxic indicators, such as release of lactic dehydrogenase (LDH) and acid phosphatase (ACP) from macrophage and its mortality, were similar to those by brucite. It suggests aluminium chloride can be used to antagonize pathogenic bioactivity of chrysotile in practice.
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