4301
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Li S. [Flow cytometric analysis of DNA from 98 cases of soft tissue tumors and its clinical significance]. ZHONGHUA WAI KE ZA ZHI [CHINESE JOURNAL OF SURGERY] 1990; 28:281-4, 318. [PMID: 2086097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The cellular DNA content of 98 soft tissue tumors was determined by means of flow cytometry and the results were discussed in relation to clinical data. It was found that DNA of all 21 benign tumors was diploid, while that of malignant tumors was both diploid and aneuploid. Among 62 sarcomas, 45 were aneuploid (73%). Cell cycle analysis disclosed that diploidy lesions had a low proportion of S and G2 + M cells while most aneuploidy lesions had a high proportion (P less than 0.01). There was a definite correlation between the size of the tumor and the presence of DNA aneuploidy. The results indicate that DNA analysis offers a clinically relevant means of characterizing soft tissue tumors.
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4302
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Lesburg C, Li S, Cragoe EJ, Deth RC. Influence of amiloride derivatives on alpha-1 adrenergic receptor-induced contractions of the rabbit aorta. J Pharmacol Exp Ther 1990; 253:530-6. [PMID: 2159996] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Derivatives of amiloride that exhibit greater specificity for inhibition of either Na+/H+ or Na+/Ca(+)+ exchange were evaluated for their ability to influence phenylephrine (PE)-induced contractions of the rabbit aorta. Most, but not all, derivatives with alkyl substituents at the 5-amino position (which exhibit greater potency for Na+/H+ exchange inhibition) caused a dose-dependent contraction at concentrations above 10 microM. At higher concentrations and longer incubation times this contraction reached 70 to 80% of the maximal PE response. Contractions induced by 5-amino-substituted amiloride derivatives were dependent upon extracellular Ca(+)+ and were inhibited by either extracellular acidification or intracellular alkalinization. This suggests that they resulted from an influence of intracellular acidification on Ca(+)+ transport. Contractile responses to PE (1 microM) were reduced by most but not all 5-amino-substituted derivatives in conjunction with tension development. Dimethylamiloride, however, failed to cause a contraction at doses up to 100 microM but was the most potent inhibitor of PE-induced contractions among the 5-amino derivatives. Dose-response curves for PE were shifted both to the right and downward by increasing concentrations of amiloride, which indicates both competitive and noncompetitive types of inhibition. Guanidino-substituted derivatives such as benzobenzamil were the most potent antagonists, producing noncompetitive inhibition in excess of 90% at a concentration of 10 microM. The differing patterns of inhibition as well as the presence or absence of intrinsic contractile activity indicate that amiloride derivatives have the potential for multiple pathways of action that modify arterial contractility.
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4303
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Li S, Zhang XY, Chen XT, Fan DM, Tan LS, Pan HZ, Huang LQ. Targeted anti-tumor agents and their cytotoxicity on gastric cancer cells in vitro. Chin Med J (Engl) 1990; 103:376-9. [PMID: 2118053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Several chemotherapeutic drugs including methotrexate, daunomycin, mitomycin C and toxin such as ricin, A chain of ricin were chosen to conjugate with murine monoclonal antibodies MGb2 and MG11. The drugs were linked to antibody directly or through human serum albumin as intermediary. The ELISA results showed that the antibody retained well the antigen-binding capacity during conjugation. These conjugates showed highly selective cytotoxic effect on target cells. In chronic cytotoxicity tests, the cytotoxic effect of these conjugates on human gastric cancer cells KATOIII was quite similar to that of free drugs or ricin, but greater than that of irrelevant conjugates, while they had a little effect on non-target cells, suggesting that the selective cytotoxicity on target cells of the conjugates be mediated by antibodies.
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4304
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Li S. [Studies on mechanism of carcinogenesis in vitro. IV. Studies on relationship between frequency of chromosome 15 monosomy and malignant expression of different clones from malignantly transformed baby hamster lung cells (BHL B4)]. ZHONGGUO YI XUE KE XUE YUAN XUE BAO. ACTA ACADEMIAE MEDICINAE SINICAE 1990; 12:126-30. [PMID: 2143112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The proceeding of malignantly transformed rodent cells in vitro is often accompanied by regular variation of chromosome numbers and structures. In order to clarify the relationship between them, we obtained five clones C1-1-5-from BHL B4, cell line, and analysed their biological characteristics. Results showed a positive correlation between frequency of chromosome 15 monosomy, it is suggested that suppressive gene of malignant phenotype be located on chromosome 15.
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4305
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Li S. [Expression of cellular oncogenes during hepatocarcinogenesis in rats]. ZHONGGUO YI XUE KE XUE YUAN XUE BAO. ACTA ACADEMIAE MEDICINAE SINICAE 1990; 12:121-5. [PMID: 2143111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
With RNA-DNA hybridization techniques, the mRNA expression of c-Ha-ras, c-Ki-ras, N-ras, and c-fos oncogenes in rat liver with neoplastic nodules or hepatocellular carcinoma induced by DENA was found to be higher than that in normal liver. No significant difference of c-myc expression was observed between normal liver and liver with neoplastic nodules or hepatocellular carcinoma. In the initiation stage of hepatocarcinogenesis in DENA+AAF+PH+PB and AAF+PH+PB model systems, the expression of c-myc increased markedly, and that of N-ras was remarkably stimulated under the action of AAF. It appears that a cooperative action between the c-myc and N-ras oncogenes was involved in the initiation of hepatocarcinogenesis. In the promotion stage, the expression of c-myc and N-ras returned to a normal level. The expression of c-fos decreased progressively in both the initiation and promotion stages, while that of c-Ha-ras and c-Ki-ras was not much changed. The significance of these results is briefly discussed.
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4306
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Hasselgren PO, James JH, Benson DW, Li S, Fischer JE. Is there a circulating proteolysis-inducing factor during sepsis? ARCHIVES OF SURGERY (CHICAGO, ILL. : 1960) 1990; 125:510-4. [PMID: 2322118 DOI: 10.1001/archsurg.1990.01410160096020] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Muscles from fed or 72-hour fasted rats were incubated in the presence of plasma from septic rats, recombinant interleukin 1 alpha (rIL-1 alpha), or recombinant tumor necrosis factor alpha (rTNF alpha), and breakdown of total and myofibrillar protein was assessed by determining release of tyrosine and 3-methylhistidine, respectively. Septic plasma stimulated total protein breakdown in muscles from 72-hour fasted rats by 10% to 20%, while myofibrillar protein breakdown was not affected. When septic plasma was added to muscles from fed rats, neither tyrosine nor 3-methylhistidine release was altered. Various concentrations of recombinant interleukin 1 alpha or recombinant tumor necrosis factor alpha did not affect total or myofibrillar protein breakdown. Since septic plasma did not stimulate myofibrillar protein breakdown, the role of a circulating factor for muscle proteolysis during sepsis remains unclear.
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4307
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Li S, Guan S. [Stability examination of the inclusion compounds of 8 Chinese medicinal volatile oils with beta-cyclodextrin]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 1990; 15:218-20, 254-5. [PMID: 2206373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The content, hence the stability of volatile oils and their main components in the inclusion compounds of 8 Chinese medicinal volatile oils with beta-cyclodextrin have been examined with different storage times. The 8 Chinese medicines are Vitex negundo var. heterophylla, Notopterygium incisum, Alpinia officinarum, Atractylodes lancea, Pogostenon cablin, Asarum heterotropoides var. mandshuricum, Schizonepeta tenuifolia and Amomum villosum.
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4308
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Tang S, Deng S, Zhou W, Li S. [Pancreatic glucagon receptor radioassay with liver cell plasma membrane in normal and streptozotocin-induced diabetic rats]. HUA XI YI KE DA XUE XUE BAO = JOURNAL OF WEST CHINA UNIVERSITY OF MEDICAL SCIENCES = HUAXI YIKE DAXUE XUEBAO 1990; 21:34-8. [PMID: 2163972] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Pancreatic glucagon receptor radioassay has been developed with rat liver cell plasma membrane prepared with sucrose gradient centrifugation. 125I-glucagon was prepared in this laboratory and the separation of B/F was done by low speed centrifugation with addition of PEG (W/V, 20%) and normal human serum. The specific binding of 125I-glucagon was 25%-35% and nonspecific binding was less than 5%. Reproducibility within and between- assay was 6.83% and 8.40% (CV%), respectively. Binding characteristics of glucagon receptor of normal and streptozotocin-induced diabetic rats were determined by using two methods, receptor dilution and conventional competitive binding assay. The results showed that there were no marked differences concerning high and low binding affinities between normal and diabetic rats, but the concentration of binding sites for both high and low affinity receptors was significantly higher for diabetic rats than normal rats. The possible mechanisms for the above results have been discussed.
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4309
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Li S, Percus JK. Density-functional theory of atoms in strong magnetic fields. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1990; 41:2344-2347. [PMID: 9903363 DOI: 10.1103/physreva.41.2344] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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4310
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Cowen P, Li S, Guy JS, Erickson GA, Blanchard D. Reactivation of latent pseudorabies virus infection in vaccinated commercial sows. Am J Vet Res 1990; 51:354-8. [PMID: 2156473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Pseudorabies virus (PRV) was isolated from 9 of 44 PRV-vaccinated seropositive sows on 5 of 11 farms. Although serum-neutralization antibody titers were 1:16 to 1:256, 28 virus isolates were obtained from tonsil, nasal, or buccal swab samples from 9 sows given 2 ml of dexamethasone/kg of body weight IM for 5 days. Pseudorabies virus was isolated from 6 of 20 sows (3 of 5 farms) given a killed-virus vaccination. Virus was obtained from 3 of 24 sows (2 of 6 farms) given modified-live virus and killed-virus vaccination. Evaluation of the 9 PRV with 5 restriction endonucleases revealed 4 PRV existing genotypes. The 9 isolated types of PRV appeared to be indistinguishable by Kpn I and BamHI restriction endonuclease analysis; however, when analyzed with Sal I, HinfI, and Pst I, isolates 7 (farm D), 8 (farm C), and 9 (farm B) had numerous differences. Isolates 1, 2, 3, and 4 (farm F) and 5 and 6 (farm G) appeared to be the same genotype when further analyzed with Pst I, HinfI, and Sal I.
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4311
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Wang Y, Zhao A, Ma Y, Yu M, Zhang Y, Dai J, Li S. [Studies on ultraweak luminescence of bacteria]. WEI SHENG WU XUE BAO = ACTA MICROBIOLOGICA SINICA 1990; 30:58-62. [PMID: 2111603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Ultraweak luminescence of Escherichia coli, Bacillus subtilis and Brevibacterium ammoniagenes was measured with high sensitive single photon counting equipment (Made in China). The results obtained from ultraweak luminescence of as above three bacterial strains were as follows: spectral distribution curves, photon emission kinetic curves or emission intensity and its qualitative relationship between intensity and bacterial counts.
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4312
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Li S. Women's employment and the production force. CHINESE JOURNAL OF POPULATION SCIENCE 1990; 2:179-85. [PMID: 12284841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/19/2023]
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4313
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Li S, Klein ES, Russo AF, Simmons DM, Rosenfeld MG. Isolation of cDNA clones encoding small nuclear ribonucleoparticle-associated proteins with different tissue specificities. Proc Natl Acad Sci U S A 1989; 86:9778-82. [PMID: 2532363 PMCID: PMC298585 DOI: 10.1073/pnas.86.24.9778] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Alternative RNA processing, such as brain- and heart-specific generation of calcitonin gene-related peptide (CGRP) transcripts from the calcitonin/CGRP gene, is thought to be mediated by tissue-specific factors. We have cloned three related but distinct cDNAs encoding small nuclear ribonucleoparticle (snRNP)-associated proteins from rat PC12 cells. One clone (Sm51) has the capacity to encode a 240-amino acid protein and its RNA transcript is expressed selectively in rat brain and pituitary but not in heart. A related cDNA, designated Sm11, predicts a protein highly homologous to but distinct from Sm51. The Sm11 transcript is very abundant in heart but barely detectable in brain. Sm51 and Sm11 appear to encode the brain and heart forms of a 28-kDa snRNP-associated protein detected by anti-Sm serum, respectively. A third clone (Sm21) encodes a protein with an altered N terminus relative to Sm51. The Sm51 transcript is expressed in the pituitary, and analysis of the pituitaries of transgenic mice harboring a mouse metallothionein I promoter-calcitonin/CGRP fusion gene reveals the splice choice to be predominantly CGRP. In situ hybridization indicates Sm51 RNA is expressed throughout neuronal structures within rat brain, including the inferior colliculus, which does not possess the machinery to generate CGRP. Although Sm51 alone cannot be sufficient to account for CGRP splicing choice in all tissues, the demonstration of discrete tissue-specific expression patterns of closely related snRNP-associated proteins is consistent with their potential role in differential RNA processing events.
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4314
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Warner RE, Berland KM, Hinnefeld JD, Zhang Z, Zhu YT, Hu XQ, Li S. Total nuclear reaction probabilities and average cross sections for 27 to 92 MeV alpha particles in silicon. PHYSICAL REVIEW. C, NUCLEAR PHYSICS 1989; 40:2473-2478. [PMID: 9966259 DOI: 10.1103/physrevc.40.2473] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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4315
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Heald SM, DiMarzio D, Croft M, Hegde MS, Li S, Greenblatt M. X-ray-absorption study of charge-density ordering in (Ba1-xKx)BiO3. PHYSICAL REVIEW. B, CONDENSED MATTER 1989; 40:8828-8833. [PMID: 9991364 DOI: 10.1103/physrevb.40.8828] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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4316
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Pedersen P, Hasselgren PO, Angerås U, Hall-Angerås M, Warner BW, LaFrance R, Li S, Fischer JE. Protein synthesis in liver following infusion of the catabolic hormones corticosterone, epinephrine, and glucagon in rats. Metabolism 1989; 38:927-32. [PMID: 2477664 DOI: 10.1016/0026-0495(89)90001-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The mediator(s) and mechanism(s) of acute-phase protein synthesis in the liver following injury and sepsis are not fully known. Elevated plasma levels of the catabolic hormones cortisol, glucagon, and epinephrine have been reported in trauma and sepsis. In previous reports, when these hormones were infused simultaneously (triple hormone infusion), several, but not all, of the metabolic alterations characteristic of sepsis occurred. In the current investigation, the effect of triple hormone infusion on hepatic protein synthesis was studied. Rats were infused intravenously during 16 hours with a solution containing corticosterone (4.2 mg/kg/h), glucagon (2.5 micrograms/kg/h), and epinephrine (6 micrograms/kg/h). Control animals were infused with a corresponding volume of vehicle. Total hepatic protein synthesis in vivo was measured with a flooding dose technique using [14C]-leucine. The synthesis of total secretory proteins and of the individual proteins albumin, complement component C3, and alpha 1-acid glycoprotein was measured in isolated, perfused liver using [3H]-leucine and a recirculating technique. Urinary excretion of nitrogen and plasma concentration of glucose were higher and plasma total amino acid concentration was lower in hormone-infused than in control rats. Total hepatic protein synthesis in vivo, expressed as the proportion of the protein pool that was replaced each day, was increased from 39% +/- 2% per day to 48% +/- 3% per day (P less than .05) by hormone infusion, but synthesis of secretory proteins in perfused liver was not significantly altered. The results suggest that although total hepatic protein synthesis may be increased by catabolic hormones, other mediator(s) are probably responsible for the stimulation of acute-phase protein synthesis in sepsis.
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4317
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Rivnyak MH, Wan TT, Stegall MH, Jacobs M, Li S. Ambulatory care use among the noninstitutionalized elderly. A causal model. Res Aging 1989; 11:292-311. [PMID: 2799058 DOI: 10.1177/0164027589113002] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
While it is recognized that need for care is the dominant factor influencing utilization of health services, little is known regarding the determinants of ambulatory care use by the noninstitutionalized elderly. It is important to examine the relationships among need factors and how physical and mental dysfunctions influence use of services. This study uses a LISREL model to identify the extent to which ambulatory care use was affected by physical or mental functioning and whether strong linkages would be exhibited by both factors.
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4318
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Wears RL, Li S, Hernandez JD, Luten RC, Vukich DJ. How many myocardial infarctions should we rule out? Ann Emerg Med 1989; 18:953-63. [PMID: 2504084 DOI: 10.1016/s0196-0644(89)80460-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
We used computer simulation to estimate the consequences of four admitting strategies (coronary care unit, intermediate care unit, routine ward care, or outpatient follow-up) on cost, outcome, admission threshold probabilities, and false-positive admission rates for patients with acute myocardial infarction. At virtually any probability of acute myocardial infarction, replacing more intensive by less intensive strategies saved money but increased mortality and decreased life expectancy. Therefore, choices among strategies may be made by using the most effective strategy for progressively lower and lower risk patients until the additional cost per additional life saved reaches a cutoff value; then, a less expensive strategy is selected. With sample cutoff values of $1 and $2 million per life saved, the marginal threshold admission probabilities were: (table; see text) These results imply that the acceptable proportion of false-positive admissions may be as high as 70% to 80%; lower rates could indicate excessively restrictive admitting policies. Clinicians may be operating closer to the optimal decision point than has previously been asserted.
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4319
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Arsenault RJ, Li S. Computer simulation of thermally activated dislocation motion: Part III. In fcc solid solutions. ACTA ACUST UNITED AC 1989. [DOI: 10.1007/bf02665500] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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4320
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Bhaduri RK, Li S, Warke CS. Zero mode of a fermion chirally coupled to a soliton. Int J Clin Exp Med 1989; 40:632-635. [PMID: 10011854 DOI: 10.1103/physrevd.40.632] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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4321
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Benson DW, Hasselgren PO, Hiyama DT, James JH, Li S, Rigel DF, Fischer JE. Effect of sepsis on calcium uptake and content in skeletal muscle and regulation in vitro by calcium of total and myofibrillar protein breakdown in control and septic muscle: results from a preliminary study. Surgery 1989; 106:87-93. [PMID: 2740990] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Because high calcium concentration in vitro stimulates muscle proteolysis, calcium has been implicated in the pathogenesis of increased muscle breakdown in different catabolic conditions. Protein breakdown in skeletal muscle is increased during sepsis, but the effect of sepsis on muscle calcium uptake and content is not known. In this study the influence of sepsis, induced in rats by cecal ligation and puncture, on muscle calcium uptake and content was studied. Sixteen hours after cecal ligation and puncture or sham operation, calcium content of the extensor digitorum longus (EDL) and soleus (SOL) muscles was determined with an atomic absorption spectrometer. Calcium uptake was measured in intact SOL muscles incubated in the presence of calcium 45 (45Ca) for between 1 and 120 minutes. Total and myofibrillar protein breakdown was determined in SOL muscles, incubated in the presence of different calcium concentrations (0; 2.5; 5.0 mmol/L), and measured as release into the incubation medium of tyrosine and 3-methylhistidine (3-MH), respectively. Calcium content was increased by 51% (p less than 0.001) during sepsis in SOL and by 10% (p less than 0.05) in EDL muscle. There was no difference in 45Ca uptake between control and septic muscles during the early phase (1 to 5 minutes) of incubation. During more extended incubation (30 to 120 minutes), muscles from septic rats took up significantly more 45Ca than control muscles (p less than 0.05). Tyrosine release by incubated SOL muscles from control and septic rats was increased when calcium was added to the incubation medium, and at a calcium concentration of 2.5 mmol/L, the increase in tyrosine release was greater in septic than in control muscle. Addition of calcium to the incubation medium did not affect 3-MH release in control or septic muscle. The results suggest that calcium uptake and content in skeletal muscle are increased during sepsis and that high calcium concentrations in vitro stimulate nonmyofibrillar protein breakdown. Muscles from septic animals may be more sensitive to the effect of calcium in vitro than muscles from nonseptic rats. Whether increased calcium uptake and content in skeletal muscle is partly responsible for accelerated muscle proteolysis during sepsis remains to be determined.
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4322
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Hasselgren PO, James JH, Benson DW, Hall-Angerås M, Angerås U, Hiyama DT, Li S, Fischer JE. Total and myofibrillar protein breakdown in different types of rat skeletal muscle: effects of sepsis and regulation by insulin. Metabolism 1989; 38:634-40. [PMID: 2661965 DOI: 10.1016/0026-0495(89)90100-5] [Citation(s) in RCA: 122] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Proteolysis is increased in sepsis, but it is not known whether myofibrillar and non-myofibrillar proteins are broken down in the same fashion, or respond to the same regulatory forces as in non-septic muscle. In this study, therefore, the effect of sepsis on total and myofibrillar protein breakdown in incubated rat extensor digitorum longus (EDL) and soleus (SOL) muscles was determined, and the response in vitro to different concentrations of insulin (10 to 10(5) microU/mL) of protein degradation was studied in incubated EDL muscles from control and septic rats. Sepsis was induced in rats weighing 40 to 60 g by cecal ligation and puncture (CLP). Control animals were sham operated. Sixteen hours after CLP or sham operation, intact EDL and SOL muscles were incubated for two hours in oxygenated Krebs-Henseleit bicarbonate buffer containing glucose (10 mmol/L) and cycloheximide (0.5 mmol/L), and total and myofibrillar protein breakdown was assessed from release into incubation medium of tyrosine and 3-methylhistidine (3-MH), respectively. Tyrosine and 3-MH were determined fluorometrically by high performance liquid chromatography (HPLC). Tissue levels of tyrosine and 3-MH remained stable both in control and septic muscles during incubation for two hours. The rate of tyrosine release was increased during sepsis by 58% (P less than .001) and 15% (NS) in EDL and SOL muscle, respectively. The corresponding figures for 3-MH were 103% (P less than .001) and 21% (NS). Tyrosine release was reduced by insulin at a concentration of 10(3) microU/mL in control muscle and at a concentration of 10(4) microU/mL in septic muscle.(ABSTRACT TRUNCATED AT 250 WORDS)
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4323
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Launder BE, Li S. A numerical study of riblet effects on laminar flow through a plane channel. ACTA ACUST UNITED AC 1989. [DOI: 10.1007/bf00404824] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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4324
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Pearlman S, Zweben A, Li S. The comparability of solicited versus clinic subjects in alcohol treatment research. BRITISH JOURNAL OF ADDICTION 1989; 84:523-32. [PMID: 2743033 DOI: 10.1111/j.1360-0443.1989.tb00609.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The increasing use of media advertisements to recruit subjects in alcohol treatment research has raised concerns about the comparability of such solicited subjects and subjects drawn from more traditional clinic populations. This paper, based on a study that involved both solicited and clinic subjects, identifies differences between the two types of subjects in terms of sociodemographic variables; pre-treatment drinking and marital adjustment; several dimensions of 'self-definition'; and three outcome measures. These findings suggest that there may be significant differences between solicited and clinic subjects and that these differences should be taken into account in the design of studies utilizing solicited subjects in order to determine the generalizability of the results.
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4325
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Zhang LY, Li S. [Subcloning of K88ac antigen gene of enterotoigenic E. coli and the restriction map of recombinant plasmid]. WEI SHENG WU XUE BAO = ACTA MICROBIOLOGICA SINICA 1989; 29:113-6. [PMID: 2678758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
We had reported a recombinant E. coli RR1(pNZ8801) which was obtained from a wild strain E. coli 79-1454. The recombinant plasmid was digested by EcoRI and generated three segments, medium segment (3.2Md) was removed, the largest and the smallest segment was ligased, then the mixture was transformed into E. coli RRI, screening Ap(r) Tc(s) clones, one of recombinants was named E. coli RR1(pNZ8802). The recombinant plasmid molecular weight is smaller, but expression of K88ac antigen is higher than first cloning. Subcloning can adhere to mucosae of piglet's intesting. Therefore, the recombinant can be use for oval living vaccine.
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