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781.
Linda M. Haines 《Biometrics》2016,72(4):1235-1245
782.
摘要 目的:观察通元针法对体外受精-胚胎移植(IVF-ET)反复种植失败(RIF)患者妊娠结局、性激素和焦虑抑郁影响。方法:前瞻性选取广州中医药大学第一附属医院2019年5月到2021年4月期间收治的IVF-ET RIF患者122例,采用随机数字表法将其分为对照组(61例,常规治疗)和研究组(61例,对照组的基础上接受通元针法治疗)。观察两组临床妊娠率、胚胎种植率,记录治疗期间不良反应发生情况,观察治疗前后子宫内膜厚度和子宫内膜血流参数、性激素和焦虑抑郁的变化情况。结果:研究组的临床妊娠率、胚胎种植率高于对照组(P<0.05)。治疗后,研究组孕酮、雌二醇水平高于对照组(P<0.05)。治疗后,研究组的子宫内膜血流搏动指数(PI)、子宫内膜血流阻力指数(RI)、子宫内膜血流收缩期最高血流速度/舒张末期血流速度(S/D)较治疗前降低,且低于对照组,子宫内膜厚度较对照组更厚(P<0.05)。治疗后,研究组Zung焦虑自评量表(SAS)、Zung抑郁自评量表(SDS)评分低于对照组(P<0.05)。两组不良反应发生率组间对比,无统计学差异(P>0.05)。结论:通元针法用于IVF-ET RIF患者,可有效调节人体性激素,缓解焦虑抑郁心情,改善妊娠结局,安全可靠。 相似文献
783.
Daily rhythms of body temperature (Tb) and activity (distance travelled) of eight free-ranging feral cats (Felis catus) were recorded via implanted body temperature loggers in conjunction with Global Positioning System technology (GPS-radio collars), over a period of 14 days. The calculation of distance travelled (as a measure for activity) from GPS-data points proved to be efficient to quantify the relationship of both variables under field conditions. Analysis of covariance (ANCOVA) was employed to disentangle the relative effects of activity and time of day on Tb. Most variance in Tb was explained by time of day (with distinctly higher Tb at night), while considerably less variation was explained by distance travelled. Most importantly, the correlation between distance travelled and Tb was significantly stronger during daytime than at night. Indeed, night-time Tb showed little fluctuation at all. Taken together, the results suggest that the circadian Tb rhythm is primarily generated by an endogenous oscillator and that high Tb during night-time are not driven by high(er) nocturnal activity. 相似文献
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785.
1. This paper outlines the use of chemical measurements as surrogate indicators of the health of sediment ecosystems. 2. For chemical measurements to be used for this purpose, links must be able to be made between adverse biological effects and the chemical composition of sediments. 3. Benchmark sediment quality guidelines allow decisions to be made about whether or not a sediment ecosystem is likely to be impacted. These guidelines are established using an effects database and a weight-of-evidence approach that gives ranges of chemical concentrations associated with known adverse biological effects. 4. If guidelines are exceeded the measured values are compared to concentrations of that contaminant in a comparable background or reference sediment. Exceedance of these concentrations leads to site-specific estimates of contaminant bioavailability. If a potential problem is indicated, laboratory sediment bioassays are used to assess the likelihood that the sediment will harm biota. 5. Trace metals are used as an example of a sediment contaminant. 相似文献
786.
Premature terminations or dropouts occur often in repeated measurement experiments. A number of methods have been proposed to analyze such data but most of them assume that the censoring mechanism is, within each group, unaffected by the mechanism generating the response variables. In this paper, we propose a model for the censoring mechanism that generates dropouts. We then show how this model can be used to check whether the censoring mechanism is affected by the response variables and other covariates. Finally, the methods of the paper are applied to the “Halothane” data set. 相似文献
787.
V. Kuhrová M. Bezděk B. Vyskot B. Koukalová J. Fajkus 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1991,81(6):740-744
Summary Two DNA sequences, R8.1 and R8.3, representing two distinct classes of tobacco genomic repeated DNA, were cloned and characterized by Southern blot analysis. Both R8.1 and R8.3 were found to be homologous to the Nicotiana tomentosiformis component of the allotetraploid Nicotiana tabacum genome, and each of them represents about 0.3% of nuclear DNA. The R8.1 and R8.3 differ in the mode of distribution in chromosomes, as revealed by in situ DNA/DNA hybridization. 相似文献
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