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411.
A low level of DNA polymerase (deoxyribonucleosidetriphosphate: deoxynucleotidyltransferase; E.C. 2.7.7.7) activity can be detected by autoradiography after incubating frozen sections of unimbibed onion seed embryos in an aqueous solution of tritium labelled deoxynucleoside triphosphate. The enzyme is sensitive to sulfhydryl reagents, and incorporation was reduced by high levels of deoxyribonuclease, but inclusion of cycloheximide, ribonuclease, or nucleoside triphosphate did not change activity. On germination, activity remained relatively constant and at a low level until 30 hr after imbibition when it began to increase significantly. 相似文献
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We study the association between weight fluctuation and activity tracking in an on-line population of thousands of individuals using digital health trackers (1,749 ≤ N ≤ 14,411, depending on the activity tracker considered) with millions of recorded activities (119,292 ≤ N ≤ 2,221,382) over the years 2013–2015. In a first between-subject analysis, we found a positive association between activity tracking frequency and weight loss. Users who log food with moderate frequency lost an additional 0.63% (CI [0.55, 0.72]; p < .001) of their body weight per month relative to low frequency loggers. Frequent workout loggers lost an additional 0.38% (CI [0.20, 0.56]; p < .001) and frequent weight loggers lost an additional 0.40% (CI [0.33, 0.47]; p < .001) as compared to infrequent loggers. In a subsequent within-subject analysis on a subset of the population (799 ≤ N ≤ 6,052) with sufficient longitudinal data, we used fixed effect models to explore the temporal relationship between a change in tracking adherence and weight change. We found that for the same individual, weight loss is significantly higher during periods of high adherence to tracking vs. periods of low adherence: +2.74% of body weight lost per month (CI [2.68, 2.81]; p < .001) during adherent weight tracking, +1.35% per month (CI [1.26, 1.43]; p < .001) during adherent food tracking, and +0.60% per month (CI [0.44, 0.76]; p < .001) during adherent workout tracking. The findings suggest that adherence to activity tracking can be utilized as a convenient real-time predictor of weight fluctuations, enabling large-scale, personalized intervention strategies. 相似文献
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Daily administration of cannabis extract (mice: 1 mg/day, rats: 5 mg/day for a period of 64 days) results in a cessation of ovarian cyclic activity as judged by vaginal smear and the absence of corpora-lutea in the ovaries of treated rats and mice. Distinct effects are produced upon uterine tissue. Uterine glands were regressed and the stromal edema was conspicuous. Cannabis extract resulted in a decreased uterine RNA, glycogen, and sialic acid concentration. It also brings about a significant depletion in the level of adrenal ascorbic acid. 相似文献
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The expression of virulence genes in the human pathogen Staphylococcus aureus is strongly influenced by the multiple global regulators. The signal transduction cascade of these global regulators is accountable for recognizing and integrating the environmental cues to regulate the virulence regulon. While the production of virulent factors by individual global regulators are comparatively straightforward to define, auto-regulation of these global regulators and their impact on other regulators is more complex process. There are several reports on the production of virulent factors that are precisely regulated by switching processes of multiple global regulators including some prominent accessory regulators such as agr, sae and sar which allows S. aureus to coordinate the gene expression, and thus, provide organism an ability to act collectively. This review implicates the mechanisms involved in the global regulation of various virulence factors along with a comprehensive discussion on the differences between these signal transduction systems, their auto-induction and, coordination of classical and some comparatively new bacterial signal transduction systems. 相似文献
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S C Arya 《BMJ (Clinical research ed.)》1991,303(6801):522-523