376
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Geng F, Tan LL, Jin XX, Yang JY, Yang K. The preparation, cytocompatibility, and in vitro biodegradation study of pure beta-TCP on magnesium. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2009; 20:1149-1157. [PMID: 19132512 DOI: 10.1007/s10856-008-3669-x] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2008] [Accepted: 12/15/2008] [Indexed: 05/27/2023]
Abstract
Biodegradable and bioactive beta-tricalcium phosphate (beta-TCP) coatings were prepared on magnesium (Mg) in order to improve its biocompatibility by a chemical method. The tensile bonding strength of beta-TCP coating and Mg substrate was measured by the standard adhesion test (ISO 13779-4). And the cytocompatibility of beta-TCP coated Mg was studied by using human osteoblast-like MG63 cells. It was found that the MG63 cells could grow well on the surface of beta-TCP coated Mg and the cell viability on beta-TCP coated Mg was above 80% during the cocultivation of MG63 cells and beta-TCP coated Mg for 10 days, indicating no cytotoxicity. It was concluded that the beta-TCP coated Mg had good cytocompatibility. The degradation of Mg substrate with beta-TCP coating in vitro was studied in detail by XRD, EDX, SEM, and ICP. The results showed that a bone-like apatite continually formed on the surface of the sample with the degradation of both Mg substrate and beta-TCP coating in Hank's solution (a simulated body fluid). The biodegradation mechanism was preliminarily analyzed in the paper.
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377
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Ma J, Ren J, Guo Y, Duan Y, Ding N, Zhou L, Li L, Yan X, Yang K, Huang L, Song Y, Xie J, Milan D, Huang L. Genome-wide identification of quantitative trait loci for carcass composition and meat quality in a large-scale White Duroc x Chinese Erhualian resource population. Anim Genet 2009; 40:637-47. [PMID: 19397518 DOI: 10.1111/j.1365-2052.2009.01892.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Carcass and meat quality traits are economically important in pigs. In this study, 17 carcass composition traits and 23 meat quality traits were recorded in 1028 F(2) animals from a White Duroc x Erhualian resource population. All pigs in this experimental population were genotyped for 194 informative markers covering the entire porcine genome. Seventy-seven genome-wide significant quantitative trait loci (QTL) for carcass traits and 68 for meat quality were mapped to 34 genomic regions. These results not only confirmed many previously reported QTL but also revealed novel regions associated with the measured traits. For carcass traits, the most prominent QTL was identified for carcass length and head weight at 57 cM on SSC7, which explained up to 50% of the phenotypic variance and had a 95% confidence interval of only 3 cM. Moreover, QTL for kidney and spleen weight and lengths of cervical vertebrae were reported for the first time in pigs. For meat quality traits, two significant QTL on SSC5 and X were identified for both intramuscular fat content and marbling score in the longissimus muscle, while three significant QTL on SSC1 and SSC9 were found exclusively for IMF. Both LM and the semimembranous muscle showed common QTL for colour score on SSC4, 5, 7, 8, 13 and X and discordant QTL on other chromosomes. White Duroc alleles at a majority of QTL detected were favourable for carcass composition, while favourable QTL alleles for meat quality originated from both White Duroc and Erhualian.
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378
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Kaplan PD, Park K, Qi J, Yang K. The shine problem in hair: review of imaging methods and measures for luster. JOURNAL OF COSMETIC SCIENCE 2009; 60:111-123. [PMID: 19450413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
There is a need for both a better understanding of the technical drivers of shiny appearance in hair and for standard methods and measures of shine. To this end, we develop standard treatment methods for changing hair shine and examine a number of image-based measurements of luster. Using psychophysical techniques to get a perceptual reference, we find that available technical measures are difficult to use when trying to quantify the small changes in shine associated with treatment.
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379
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Do DV, Nguyen QD, Shah SM, Browning DJ, Haller JA, Chu K, Yang K, Cedarbaum JM, Vitti RL, Ingerman A, Campochiaro PA. An exploratory study of the safety, tolerability and bioactivity of a single intravitreal injection of vascular endothelial growth factor Trap-Eye in patients with diabetic macular oedema. Br J Ophthalmol 2009; 93:144-9. [DOI: 10.1136/bjo.2008.138271] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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380
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Guo T, Ren J, Yang K, Ma J, Zhang Z, Huang L. Quantitative trait loci for fatty acid composition in longissimus dorsi and abdominal fat: results from a White Duroc x Erhualian intercross F2 population. Anim Genet 2008; 40:185-91. [PMID: 19133937 DOI: 10.1111/j.1365-2052.2008.01819.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
A whole-genome scan was performed on 660 F(2) animals including 250 barrows and 410 gilts in a White Duroc x Erhualian intercross population to detect quantitative trait loci (QTL) for fatty acid composition in the longissimus dorsi muscle and abdominal fat. A total of 153 QTL including 63 genome-wide significant QTL and 90 suggestive effects were identified for the traits measured. Significant effects were mainly evident on pig chromosomes (SSC) 4, 7, 8 and X. No association was detected on SSC3 and 11. In general, the QTL detected in this study showed distinct effects on fatty acid composition in the longissimus muscle and abdominal fat. The QTL for fatty acid composition in abdominal fat did not correspond to those identified previously in backfat and the majority of QTL for the muscle fatty acid composition were mapped to chromosomal regions different from previous studies. Two regions on SSC4 and SSC7 showed significant pleiotropic effects on monounsaturated (MUFA) and polyunsaturated fatty acid (PUFA) in both longissimus muscle and abdominal fat. Another two QTL with significant multi-faceted effects on MUFA and PUFA in the longissimus muscle were found each on SSC8 and SSCX. Chinese Erhualian alleles were associated with increased ratios of MUFA to saturated fatty acid at most of the QTL detected, showing beneficial effect in terms of human health.
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381
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Gong J, Zhu C, Zhuang R, Song C, Li Q, Xu Z, Wei Y, Yang K, Yang A, Chen L, Jin B. Establishment of an enzyme-linked immunosorbent assay system for determining soluble CD96 and its application in the measurement of sCD96 in patients with viral hepatitis B and hepatic cirrhosis. Clin Exp Immunol 2008; 155:207-15. [PMID: 19040604 DOI: 10.1111/j.1365-2249.2008.03829.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
CD96, previously named T cell activation increased late expression (Tactile), is a transmembrane molecule that functions as an activated receptor on natural killer cells. It is well known that many transmembrane molecules have soluble forms, which were either shed from the cell surface or spliced at mRNA level. In many cases, the levels of soluble forms in the circulation could be used as biomarkers of lymphocyte activation in bacterial or virus infection, tumour, transplantation and autoimmune disease. To investigate whether CD96 could be released into the sera and the possible biological function of soluble hCD96 (sCD96), we generated and characterized five clones of anti-hCD96 mouse monoclonal antibodies (mAb) and developed a sandwich enzyme-linked immunosorbent assay (ELISA) system based on two anti-hCD96 mAbs with different epitope specificities. Using this ELISA system, sCD96 in serum samples from 99 healthy individuals could be detected. Furthermore, we found that the level of sCD96 in serum samples from patients with chronic viral hepatitis B or classes B and C of hepatic cirrhosis classified using the Child-Pugh score was much higher (P < 0.001 versus healthy individuals; P = 0.006 versus healthy individuals respectively) than that from healthy individuals (0.98 ng/ml). Our study demonstrates for the first time that sCD96 existed in sera, and suggests that sCD96 may be used as a serous marker for some diseases such as chronic viral hepatitis B infection or hepatic cirrhosis in classes B and C. The level of sCD96 in patients' serum may have some relationship with a chronic inflammatory reaction.
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382
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Yang K, Wen J, Liu X, Kijlstra A, Chen L, Chi W, Zhou H, Huang X, Yang P. Inhibitory effect of rapamycin and dexamethasone on production of IL-17 and IFN-gamma in Vogt-Koyanagi-Harada patients. Br J Ophthalmol 2008; 93:249-53. [PMID: 19019941 DOI: 10.1136/bjo.2008.142489] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
AIMS To evaluate the effect of rapamycin (RAPA) and dexamethasone (DEX) on the production of IL-17 and IFN-gamma by peripheral blood mononuclear cells (PBMCs) from Vogt-Koyanagi-Harada (VKH) patients and healthy individuals. METHODS Blood samples were drawn from 10 active VKH patients and 10 healthy individuals. PBMCs were cultured with or without anti-CD3 and anti-CD28 antibodies in the presence or absence of different concentrations of RAPA or DEX for 72 h. IL-17 and IFN-gamma concentrations in the supernatants were measured by enzyme-linked immunosorbent assay (ELISA). RESULTS The expression of IL-17 and IFN-gamma was significantly increased in active VKH patients compared with that in healthy controls. Both RAPA and DEX were able to significantly inhibit the production of IL-17 and IFN-gamma by PBMCs from patients and healthy controls. RAPA was able to completely inhibit IL-17 production at a dosage of 10 ng/ml but only partially suppressed IFN-gamma production even at a much higher concentration (1000 ng/ml). DEX inhibited the production of both IL-17 and IFN-gamma by approximately 70%. CONCLUSIONS This study indicates that both RAPA and DEX inhibit the production of IL-17 and IFN-gamma by PBMCs. RAPA is much stronger in inhibiting the production of IL-17 than DEX.
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383
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Seo Y, Kim M, Yoo S, Cho C, Yang K, Yoo H, Choi C, Ji Y, Lee D, Han C. Stereotactic Radiation Therapy in Hepatocellular Carcinoma Who had Failed other Treatment Modality. Int J Radiat Oncol Biol Phys 2008. [DOI: 10.1016/j.ijrobp.2008.06.1699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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384
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Choi C, Cho C, Yoo S, Kim M, Yoo H, Yang K, Seo Y, Kang J, Lee D. Image Guided Stereotactic Radiation Therapy in Patients with Isolated Paraaortic Lymph Node Metastasis from Carcinoma of Uterus. Int J Radiat Oncol Biol Phys 2008. [DOI: 10.1016/j.ijrobp.2008.06.1184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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385
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Bian J, Yang K, Packard N, Sidky E, Boone J, Pan X. SU-GG-I-21: Image Reconstruction From Sparse Data in Breast CT. Med Phys 2008. [DOI: 10.1118/1.2961420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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386
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Yang K, Kwan A, Huang S, Boone J. TH-C-332-03: Noise Power Properties of a Cone-Beam CT System for Breast Cancer Detection. Med Phys 2008. [DOI: 10.1118/1.2962868] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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387
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Dy J, Guan H, Sampath-Kumar R, Richardson B, Yang K. Placental 11β-Hydroxysteroid Dehydrogenase Type 2 is Reduced in Pregnancies Complicated with Idiopathic Intrauterine Growth Restriction: Evidence That This is Associated With an Attenuated Ratio of Cortisone to Cortisol in the Umbilical Artery. Placenta 2008; 29:193-200. [DOI: 10.1016/j.placenta.2007.10.010] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2007] [Revised: 10/24/2007] [Accepted: 10/25/2007] [Indexed: 11/29/2022]
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388
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Evens M, Trace DA, Yang K. Using a Java Dynamic Tree to Manage the Terminology in a Suite of Medical Applications. Methods Inf Med 2008; 47:499-504. [DOI: 10.3414/me0555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Summary
Objectives:
Now that the National Library of Medicine has made SNOMED-CT widely available, we are trying to manage the terminology of a whole suite of medical applications and map our terminology into that in SNOMED.
Methods:
This paper describes the design and implementation of the Java Dynamic Tree that provides structure to our medical terminology and explains how it functions as the core of our system.
Results:
The tree was designed to reflect the stages in a patient interview, so it contains components for identifying the patient and the provider, a large set of chief complaints, review of systems, physical examination, several history modules, medications, laboratory tests, imaging, and special procedures. The tree is mirrored in a commercial DBMS, which also stores multi-encounter patient data, disorder patterns for our Bayesian diagnostic system, and the data and rules for other expert systems. The DBMS facilitates the import and export of large terminology files.
Conclusions:
Our Java Dynamic Tree allows the health care provider to view the entire terminology along with the structure that supports it, as well as the mechanism for the generation of progress notes and other documents, in terms of a single hierarchical structure. Changes in terminology can be propagated through the system under the control of the expert. The import/ export facility has been a major help by replacing our original terminology by the terminology in SNOMED-CT.
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389
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Choi C, Cho C, Kim G, Park K, Jo M, Lee C, Yoo S, Kim M, Yang K, Yoo H. Stereotactic Radiation Therapy of Localized Prostate Cancer Using Cyberknife. Int J Radiat Oncol Biol Phys 2007. [DOI: 10.1016/j.ijrobp.2007.07.1481] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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390
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Seo Y, Kim M, Yoo S, Cho C, Yang K, Yoo H, Choi C, Lee D, Park J. The Role of Stereotactic Radiation Therapy in the Localized Unresectable Liver Cancer. Int J Radiat Oncol Biol Phys 2007. [DOI: 10.1016/j.ijrobp.2007.07.1355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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391
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Choi C, Kim M, Yoo S, Cho C, Yoo H, Yang K, Seo Y, Lee D, Hwang D, Moon S. Isolated Metastasis From Colorectal Cancer Treated by Stereotactic Radiation Therapy. Int J Radiat Oncol Biol Phys 2007. [DOI: 10.1016/j.ijrobp.2007.07.1350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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392
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Yang K, Li J, Liu Y, Ma B, Roberts H, Tan J, Tian J, Wu T, Zhang P. Microwave therapy for cervical ectropion. Cochrane Database Syst Rev 2007; 2007:CD006227. [PMID: 17943899 PMCID: PMC8922973 DOI: 10.1002/14651858.cd006227.pub2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND Cervical ectropion is considered as one of the most common types of chronic cervicitis in China. Topical treatments for cervical ectropion including microwave tissue coagulation, are widely used in many hospitals in China. Nowadays, the necessary intervention for inflammatory cervical ectopy is controversial. OBJECTIVES To compare the efficacy and potential side effects of microwave tissue coagulation with other interventions or no intervention in the treatment of cervical ectropion. SEARCH STRATEGY We searched the Cochrane Menstrual Disorders and Subfertility Group Trials Register, Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library 2006, Issue 1), MEDLINE (1966 to 2005), EMBASE (1974 to 2005); The Chinese Biomedical Database (CBM, 1978 to 2005), The Chinese Medical Current Contents (CMCC, 1994 to 2005), CAJ Full-text Database (1994 to 2005) and Chinese Scientific Journals Database (1989 to 2005). We also searched related literature on the Internet with search engines such as Google, searched the reference lists of articles and hand searched relevant Chinese journals. SELECTION CRITERIA Only authentic randomized controlled trials (RCTs) were included. DATA COLLECTION AND ANALYSIS Two authors independently interviewed the original authors of claimed RCTs published in China and then assessed the quality of the three included RCTs and extracted data. MAIN RESULTS No studies were found that met the participant inclusion criteria of the protocol. Although three studies were identified as authentic RCTs from 92 potential RCTs, it was not possible to confirm that the participants were symptomatic prior to treatment. Of these three studies two trials compared microwave therapy with laser and one compared microwave therapy with interferon-alpha suppository therapy. Microwave therapy showed a better effect on cervical appearance over laser therapy in the women with grade II and III and also improved cervical appearance over interferon-alpha suppository therapy. There was no difference in grade I women. Microwave therapy showed less adverse bleeding than laser therapy during the treatment. However, the methodological quality of the three RCTs was generally low. No trial compared treatment to no intervention and most trials didn't assess relief of symptoms or quality of life and satisfaction, which are very important to women. AUTHORS' CONCLUSIONS There are no RCTs comparing microwave therapy with other treatments or no treatment in symptomatic women with cervical ectropion. Although microwave therapy improved the appearance of the cervix over both laser therapy and interferon-alpha suppository therapy it is not clear if there is any other benefit for women.
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393
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Yang K, Tan JL, Wu TX. Alkylating agents for Waldenstrom's macroglobulinemia. Hippokratia 2007. [DOI: 10.1002/14651858.cd006719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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394
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Yang K, Boone J. TU-FF-A4-06: Motion Blurring Correction for a Cone Beam CT System with Image Decomposition and Deconvolution Method. Med Phys 2007. [DOI: 10.1118/1.2761442] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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395
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Liang H, Yang Y, Yang K, Wu Y, Boone JM, Cherry SR. A microPET/CT system for in vivo small animal imaging. Phys Med Biol 2007; 52:3881-94. [PMID: 17664583 DOI: 10.1088/0031-9155/52/13/015] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
A microCT scanner was designed, fabricated and integrated with a previously reported microPET II scanner (Tai et al 2003 Phys. Med. Biol. 48 1519, Yang et al 2004 Phys. Med. Biol. 49 2527), forming a dual modality system for in vivo anatomic and molecular imaging of the mouse. The system was designed to achieve high-spatial-resolution and high-sensitivity PET images with adequate CT image quality for anatomic localization and attenuation correction with low x-ray dose. The system also has relatively high throughput for screening, and a flexible gantry and user interface. X-rays were produced by a 50 kVp, 1.5 mA fixed tungsten anode tube, with a focal spot size of 70 microm. The detector was a 5 x 5 cm(2) photodiode detector incorporating 48 microm pixels on a CMOS array and a fast gadolinium oxysulfide (GOS) intensifying screen. The microCT system has a flexible C-arm gantry design with adjustable detector positioning, which acquires CT projection images around the common microPET/CT bed. The design and the initial characterization of the microCT system is described, and images of the first mouse scans with microPET/CT scanning protocols are shown.
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396
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Huang S, Zheng D, Boone J, Yang K, Packard N. WE-E-L100J-02: A Phantom Study of Contrast-Enhanced Dual Energy Mammography (CEDEM). Med Phys 2007. [DOI: 10.1118/1.2761577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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397
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Hu CH, Chen DM, Wang YM, Xu DS, Yang K. First-principles investigations of the pressure-induced structural transitions in Mg(AlH(4))(2). JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2007; 19:176205. [PMID: 21690951 DOI: 10.1088/0953-8984/19/17/176205] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
A systematic investigation is presented of the high-pressure structural stability of Mg(AlH(4))(2) using a plane-wave pseudo-potential method. The total-energy calculations show that under ambient pressure the structure of α-Mg(AlH(4))(2) found by experiments is more stable than the other proposed structures, and with pressure increasing the α to β (δ-Zr(MoO(4))(2)-type structure) and β to γ (Ca(BF(4))(2)-type structure) transitions occur at 0.67 and 10.28 GPa respectively, accompanied with volume reductions of 6.6% and 8.7%. A detailed study of the electronic structures reveals the bonding characteristics between Al and H and between Mg and H as well as the nonmetallic features of α, β, and γ phases under pressure of up to 20.0 GPa. Their electronic structures are mainly responsible for the relative high-pressure stability of the three phases. Finally, an analysis of their structural relations indicates that it is possible to produce the [Formula: see text] structural transition by applying pressure.
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398
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Kucherlapati M, Nguyen A, Kuraguchi M, Yang K, Fan K, Bronson R, Wei K, Lipkin M, Edelmann W, Kucherlapati R. Tumor progression in Apc(1638N) mice with Exo1 and Fen1 deficiencies. Oncogene 2007; 26:6297-306. [PMID: 17452984 DOI: 10.1038/sj.onc.1210453] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Flap endonuclease 1 (Fen1) and exonuclease 1 (Exo1) have sequence homology and similar nuclease capabilities. Both function in multiple pathways of DNA metabolism, but appear to have distinct in vivo nucleic acid substrates, and therefore distinct metabolic roles. When combined with Apc(1638N), Fen1 promotes tumor progression. Because of functional similarity to Fen1, and because Exo1 is involved in DNA mismatch repair (MMR) by interaction with Msh2 and Mlh1, genes that cause hereditary nonpolyposis colorectal cancer (HNPCC), we investigated the possibility that Exo1 might also act as a modifier to Apc(1638N). We present evidence that mice with combined mutations in Apc(1638N) and Exo1 and Apc(1638N), Exo1 and Fen1 genes show moderate increased tumor incidence and multiplicity in comparison to Apc(1638N) siblings, implying a low penetrance role for Exo1 in early gastrointestinal (GI) tumorigenesis. Despite a decrease in median survival (10 months) in Apc(1638N) Exo1 mice, their tumors do not progress any more rapidly than those of Apc(1638N). Instead these animals die from infections that are the result of impaired immune response. Apc(1638N) Exo1 Fen1 mice survive longer (18 months), and therefore appear relatively immune competent. They die of invasive GI tumors that display microsatellite instability (MSI). Our results show that Exo1 has a modest tumor suppressor function.
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399
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Xie BP, Yang K, Shen DW, Zhao JF, Ou HW, Wei J, Gu SY, Arita M, Qiao S, Namatame H, Taniguchi M, Kaneko N, Eisaki H, Tsuei KD, Cheng CM, Vobornik I, Fujii J, Rossi G, Yang ZQ, Feng DL. High-energy scale revival and giant kink in the dispersion of a cuprate superconductor. PHYSICAL REVIEW LETTERS 2007; 98:147001. [PMID: 17501304 DOI: 10.1103/physrevlett.98.147001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2006] [Indexed: 05/15/2023]
Abstract
In the present photoemission study of a cuprate superconductor Bi1.74Pb0.38Sr1.88CuO6+delta, we discovered a large scale dispersion of the lowest band, which unexpectedly follows the band structure calculation very well. Similar behavior observed in blue bronze and the Mott insulator Ca2CuO2Cl2 suggests that the origin of hopping-dominated dispersion in an overdoped cuprate might be quite complicated. A giant kink in the dispersion is observed, and the complete self-energy containing all interaction information is extracted for a doped cuprate. These results recovered significant missing pieces in our current understanding of the electronic structure of cuprates.
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400
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Yang K, Chen LP, Cai YQ, Hiraoka N, Li S, Zhao JF, Shen DW, Song HF, Tian H, Bai LH, Chen ZH, Shuai ZG, Feng DL. Inelastic x-ray scattering study of exciton properties in an organic molecular crystal. PHYSICAL REVIEW LETTERS 2007; 98:036404. [PMID: 17358703 DOI: 10.1103/physrevlett.98.036404] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2006] [Indexed: 05/14/2023]
Abstract
Excitons in a complex organic molecular crystal were studied by inelastic x-ray scattering (IXS) for the first time. The dynamic dielectric response function is measured over a large momentum transfer region, from which an exciton dispersion of 130 meV is observed. Semiempirical quantum chemical calculations reproduce well the momentum dependence of the measured dynamic dielectric responses, and thus unambiguously indicate that the lowest Frenkel exciton is confined within a fraction of the complex molecule. Our results demonstrate that IXS is a powerful tool for studying excitons in complex organic molecular systems. Besides the energy position, the IXS spectra provide a stringent test on the validity of the theoretically calculated exciton wave functions.
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