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121.
Ralph W. deVere White Alexander Tsodikov Eschelle C. Stapp Stephanie E. Soares Hajime Fujii Robert M. Hackman 《Nutrition and cancer》2013,65(8):1036-1043
The efficacy and safety of consuming high-dose isoflavone supplements for prostate cancer is not clear. A double-blind, placebo controlled, randomized trial was conducted in 53 men with prostate cancer enrolled in an active surveillance program. The treatment group consumed a supplement containing 450 mg genistein, 300 mg daidzein, and other isoflavones daily for 6 mo. Prostate-specific antigen (PSA) was measured in both groups at baseline, 3 mo, and 6 mo, and serum concentrations of genistein, daidzein, and equol were assessed at baseline and 6 mo in the treatment group. Following the completion of the 6-mo double-blind study, men were enrolled in a 6-mo open label trial with the same isoflavone-rich supplement, and PSA was measured at 3 and 6 mo. PSA concentrations did not change in either group after 6 mo or after 12 mo when the open-label study was included. The 6 mo serum concentrations of genistein and daidzein (39.85 and 45.59 μmol/l, respectively) were significantly greater than baseline values and substantially higher than levels previously reported in other studies. Equol levels did not change. Although high amounts of aglycone isoflavones may result in significantly elevated serum concentrations of genistein and daidzein, these dietary supplements alone did not lower PSA levels in men with low-volume prostate cancer. 相似文献
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Evelina Chapman Ludovic Reveiz Amy Chambliss Stephanie Sangalang Xavier Bonfill 《Journal of clinical epidemiology》2013,66(1):105-112
ObjectivesTo use an “evidence-mapping” approach to assess the usefulness of Cochrane reviews in identifying research gaps in the maternal health.Study Design and SettingThe article describes the general mapping, prioritizing, reconciling, and updating approach: (1) identifying gaps in the maternal health research using published systematic reviews and formulating research questions, (2) prioritizing questions using Delphi method, (3) reconciling identified research priorities with the existing literature (i.e., searching of ongoing trials in trials registries), (4) updating the process. A comprehensive search of Cochrane systematic reviews published or updated from January 2006 to March 2011 was performed. We evaluated the “Implications for Research” section to identify gaps in the research.ResultsOur search strategy identified 695 references; 178 systematic reviews identifying at least one research gap were used. We formulated 319 research questions, which were classified into 11 different categories based on the direct and indirect causes of maternal mortality: postpartum hemorrhage, abortion, hypertensive disorders, infection/sepsis, caesarean section, diabetes, pregnancy prevention, preterm labor, other direct causes, indirect causes, and health policies and systems. Most research questions concerned the effectiveness of clinical interventions, including drugs (42.6%), nonpharmacologic interventions (16.3%), and health system (14.7%).ConclusionIt is possible to identify gaps in the maternal health research by using this approach. 相似文献
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Men who have sex with men (MSM) make up nearly half of all people living with HIV in the United States. The prevalence of the epidemic in this population makes it vitally important to understand the transmission of the infection and to develop methods to prevent its spread. The current study uses longitudinal diary methods to examine relationships between substance use and unprotected anal intercourse in a sample of 158 HIV-positive, mostly ethnic minority MSM. Results indicate that both general substance use and use of specific drugs (i.e., inhalants, cocaine, crack, and club drugs) have a substantial impact on the sexual risk behavior of this population. 相似文献
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Laura Barberi Bianca Maria Scicchitano Manuela De Rossi Anne Bigot Stephanie Duguez Aurore Wielgosik Claire Stewart Jamie McPhee Maria Conte Marco Narici Claudio Franceschi Vincent Mouly Gillian Butler-Browne Antonio Musarò 《Biogerontology》2013,14(3):273-292
Although adult skeletal muscle is composed of fully differentiated fibers, it retains the capacity to regenerate in response to injury and to modify its contractile and metabolic properties in response to changing demands. The major role in the growth, remodeling and regeneration is played by satellite cells, a quiescent population of myogenic precursor cells that reside between the basal lamina and plasmalemma and that are rapidly activated in response to appropriate stimuli. However, in pathologic conditions or during aging, the complete regenerative program can be precluded by fibrotic tissue formation and resulting in functional impairment of the skeletal muscle. Our study, along with other studies, demonstrated that although the regenerative program can also be impaired by the limited proliferative capacity of satellite cells, this limit is not reached during normal aging, and it is more likely that the restricted muscle repair program in aging is presumably due to missing signals that usually render the damaged muscle a permissive environment for regenerative activity. 相似文献