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The statistical characteristics of body weight in a number of longitudinally studied mouse populations were examined. Frequency distribution of body weights appears to be rather “fluid” (though within a strict range), changing from symmetric to positively skewed to symmetric and finally to negatively skewed as the mice pass through the stages of early maturity, middle age, and senescence. Because body weight is a highly integrated physiological variable, it is postulated that various diets which affect survivorship would affect body weight frequency distribution similarly. The data from studies with an antioxidant diet and two toxic diets support this hypothesis. In general, the effects on body weight can be assessed in a relatively short time (6–9 months) after initiation of the experiment and 4–6 months before the effect of the experimental diet is manifested in the population's survivorship, thus offering an analytical tool for considerable shortening of the duration of such studies.  相似文献   
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Big Events are processes like macroeconomic transitions that have lowered social well-being in various settings in the past. Greece has been hit by the global crisis and experienced an HIV outbreak among people who inject drugs. Since the crisis began (2008), Greece has seen population displacement, inter-communal violence, cuts in governmental expenditures, and social movements. These may have affected normative regulation, networks, and behaviors. However, most pathways to risk remain unknown or unmeasured. We use what is known and unknown about the Greek HIV outbreak to suggest modifications in Big Events models and the need for additional research.  相似文献   
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Pituitary - Pituitary adenomas affect patients’ quality-of-life (QoL) across several domains, with long-term implications even following gross-total resection or disease remission. While...  相似文献   
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Sleep and Breathing - To compare physical, psychological, and physiological adaptations between rotating and morning shift health workers using objective and subjective approaches. Forty nurses...  相似文献   
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Martial Hamon  Angelos Sourgounis 《European heart journal》2008,29(7):954; author reply 954-954; author reply 955
We read with interest the article by Brasselet et al.1 comparingoperator radiation exposure with different vascular access sites,namely radial vs. femoral access, during the performance ofcoronary angiograms or other percutaneous coronary interventions(PCI). This important concern merits attention, and has beendebated extensively over the last few years. As mentioned bythe authors,  相似文献   
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Resistance to antiviral treatment for chronic hepatitis B virus (HBV) has been associated with mutations in the HBV polymerase region. This study aimed at developing an ultrasensitive method for quantifying viral populations with all major HBV resistance-associated mutations, combining the amplification refractory mutation system real-time PCR (ARMS RT-PCR) with a molecular beacon using a LightCycler. The discriminatory ability of this method, the ARMS RT-PCR with molecular beacon assay, was 0.01 to 0.25% for the different HBV resistance-associated mutations, as determined by laboratory-synthesized wild-type (WT) and mutant (Mut) target sequences. The assay showed 100% sensitivity for the detection of mutant variants A181V, T184A, and N236T in samples from 41 chronically HBV-infected patients under antiviral therapy who had developed resistance-associated mutations detected by direct PCR Sanger sequencing. The ratio of mutant to wild-type viral populations (the Mut/WT ratio) was >1% in 38 (63.3%) of 60 samples from chronically HBV-infected nucleos(t)ide analogue-naive patients; combinations of mutations were also detected in half of these samples. The ARMS RT-PCR with molecular beacon assay achieved high sensitivity and discriminatory ability compared to the gold standard of direct PCR Sanger sequencing in identifying resistant viral populations in chronically HBV-infected patients receiving antiviral therapy. Apart from the dominant clones, other quasispecies were also quantified. In samples from chronically HBV-infected nucleos(t)ide analogue-naive patients, the assay proved to be a useful tool in detecting minor variant populations before the initiation of the treatment. These observations need further evaluation with prospective studies before they can be implemented in daily practice.  相似文献   
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