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排序方式: 共有1926条查询结果,搜索用时 0 毫秒
91.
92.
Iyengar P Combs TP Shah SJ Gouon-Evans V Pollard JW Albanese C Flanagan L Tenniswood MP Guha C Lisanti MP Pestell RG Scherer PE 《Oncogene》2003,22(41):6408-6423
93.
Effects of dietary selenium supplementation on DNA damage and apoptosis in canine prostate 总被引:6,自引:0,他引:6
Waters DJ Shen S Cooley DM Bostwick DG Qian J Combs GF Glickman LT Oteham C Schlittler D Morris JS 《Journal of the National Cancer Institute》2003,95(3):237-241
The trace mineral selenium inhibits cancer development in a variety of experimental animal models. We used an in vivo canine model to evaluate the effects of dietary selenium supplementation on DNA damage in prostate tissue and on apoptosis in prostate epithelial cells. Sexually intact elderly male beagle dogs were randomly assigned to receive an unsupplemented diet (control group) or diets that were supplemented with selenium (treatment group), either as selenomethionine or as high-selenium yeast at 3 micro g/kg or 6 micro g/kg body weight per day for 7 months. The extent of DNA damage in prostate cells and in peripheral blood lymphocytes, as determined by the alkaline comet assay, was lower among the selenium-supplemented dogs than among the control dogs (prostate P<.001; peripheral blood lymphocytes P =.003; analysis of variance) but was not associated with the activity of the antioxidant enzyme glutathione peroxidase in plasma. The median number of terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling-positive (i.e., apoptotic) prostate epithelial cells was 3.7 (interquartile range = 1.1-7.6) for the selenium-supplemented dogs and 1.7 (interquartile range = 0.2-2.8) for the control dogs ( P =.04, Mann-Whitney U test). These data suggest that dietary selenium supplementation decreases DNA damage and increases epithelial cell apoptosis within the aging canine prostate. 相似文献
94.
Beavers MP Gunnet JW Hageman W Miller W Moore JB Zhou L Chen RH Xiang A Urbanski M Combs DW Mayo KH Demarest KT 《Drug design and discovery》2001,17(3):243-251
A first-in-class non-peptide antagonist of the motilin receptor was identified through electronic screening of our corporate database against a 3D pharmacophore. The pharmacophore was developed from the motilin 22 residue endogenous peptide using NMR structural data, principles of peptide folding, and peptide structure activity relationships. The NMR data supported helical content within the peptide, and both the hydrophobic staple and N-capping box motifs were identified in the motilin sequence. The conformational features of these motifs were imposed on the peptide structure, providing a constrained conformer as a starting point for database searching. A trisubstituted cyclopentene lead was identified directly from the electronic search. Compounds in this series inhibit the binding of 125I-motilin to human antral smooth muscle membrane and antagonize motilin-induced intracellular calcium mobilization in cells expressing the human motilin receptor. A potent compound developed through optimization, RWJ 68023, is active in binding and cell-based functional assays and is also effective in inhibiting motilin-induced contractility in segments of rabbit duodenum. This orally active compound is currently undergoing clinical evaluation for the treatment of gastrointestinal disorders associated with altered motility. 相似文献
95.
Selenium in global food systems 总被引:26,自引:0,他引:26
Combs GF 《The British journal of nutrition》2001,85(5):517-547
Food systems need to produce enough of the essential trace element Se to provide regular adult intakes of at least 40 microg/d to support the maximal expression of the Se enzymes, and perhaps as much as 300 microg/d to reduce risks of cancer. Deprivation of Se is associated with impairments in antioxidant protection, redox regulation and energy production as consequences of suboptimal expression of one or more of the Se-containing enzymes. These impairments may not cause deficiency signs in the classical sense, but instead contribute to health problems caused by physiological and environmental oxidative stresses and infections. At the same time, supranutritional intakes of Se, i.e. intakes greater than those required for selenocysteine enzyme expression, appear to reduce cancer risk. The lower, nutritional, level is greater than the typical intakes of many people in several parts of the world, and few populations have intakes approaching the latter, supranutritional, level. Accordingly, low Se status is likely to contribute to morbidity and mortality due to infectious as well as chronic diseases, and increasing Se intakes in all parts of the world can be expected to reduce cancer rates. 相似文献
96.
Clinical evaluation of a new recombinant antigen-based cytomegalovirus immunoglobulin M immunoassay in liver transplant recipients 总被引:1,自引:0,他引:1
Halling VW Maine GT Groettum CM Wilson JA Spesard J Brojanac S Combs B Wachta D Holas C Wilson T Wang D Tomazic-Allen S Lazzarotto T Landini MP Jevremovic-Simovic S Wiesner RH Paya CV Smith TF 《Transplantation》2001,71(3):395-397
BACKGROUND: Human cytomegalovirus (CMV) is a significant cause of morbidity and mortality among transplant recipients. Monitoring transplant recipients by CMV IgM serology has been questioned by several studies due to the reported insensitivity of serologic tests relative to antigen detection methods. METHODS: In this retrospective study, we have evaluated the performance of the new recombinant antigen-based Abbott AxSYM CMV IgM assay and compared it with CMV culture technique in a cohort of 40 liver transplant recipients who did not receive antiviral prophylaxis. RESULTS: The sensitivity, specificity, and positive and negative predictive values for detection of CMV disease by the AxSYM CMV IgM assay were 90.0%, 60.0%, 69.2%, and 85.7%, respectively, and by culture the values were 100%, 55.0%, 69.0%, and 100%, respectively. Detection of CMV IgM occurred before or at the time of CMV disease in only R+ recipients. CONCLUSION: Although this assay is a sensitive test for CMV-specific IgM, detection of CMV IgM preceded detection of virus by culture in patients only when the liver transplant recipient was CMV immune before transplantation (R+). 相似文献
97.
Cluster analysis was utilized to derive sub-types from a group of 53 males with HIV infection based on scores from several psychological measures. Measures administered included the Beck Depression Inventory, Life Orientation Test, Rosenberg Self-Esteem Test and the Internal Control Index. Three sub-types were identified: (1) average performing sub-type (2) severely dysfunctional sub-type, and (3) highly adaptive sub-type. All three sub-types showed different levels and patterns of test performance. Results are discussed in terms of sub-type characteristics and potential treatment issues. 相似文献
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100.
Gina Kearney MSN RN CS AHN-BC JeMe Cioppa-Mosca PT MBA Margaret G. E. Peterson Ph.D C. Ronald MacKenzie MD 《HSS journal》2007,3(2):198-201
In an outpatient rehabilitation setting, both patients’ use and therapists’ knowledge of complementary and alternative medicine
(CAM) varies widely. Based on this observation and a recognition of CAM as an emerging practice area for rehabilitation professionals,
it was felt that a thorough and consistent approach to the education and orientation of physical therapists to the world of
CAM and integrative care was needed. This special interest paper will describe one center’s approach, development, and use
of a unique and comprehensive training manual designed to provide both a structured and standardized approach for educating
physical therapists about CAM and related therapeutic modalities. This innovative teaching tool allows for multiple methods
of content delivery within a multidisciplinary format and can be used for those who practice currently or desire to practice
in an integrative care environment. 相似文献