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131.
摘要 目的:探讨血清C-C基序趋化因子配体17(CCL17)、CXC趋化因子受体4(CXCR4)与重度子痫前期(SPE)患者辅助性T细胞(Th)17细胞的相关性分析及对母婴结局的影响。方法:选择2018年3月至2021年3月苏州大学附属第二医院妇产科收治的169例SPE患者(SPE组)和77例健康孕产妇(对照组)。检测血清CCL 17、CXCR4水平和外周血Th17细胞及其细胞因子。Pearson分析血清CCL 17、CXCR4水平与外周血Th17细胞及其细胞因子的关系,多因素Logistic回归分析SPE母婴结局不良的相关因素。结果:SPE组血清CCL17、CXCR4水平低于对照组(P<0.05),外周血Th17细胞占比、血清白细胞介素(IL)-17水平高于对照组(P<0.05)。血清CCL17、CXCR4水平与外周血Th17细胞占比、血清IL-17水平呈负相关(P<0.05)。母婴结局不良53例,母婴结局良好116例,母婴结局不良组血清CCL 17、CXCR4水平低于母婴结局良好组(P<0.05)。高Th17细胞占比、年龄大、低水平CCL17、CXCR4是SPE患者母婴结局不良的危险因素(P<0.05)。结论:SPE患者血清CCL17、CXCR4水平降低,且与外周血Th17细胞占比增加,血清IL-17水平增高有关,低水平CCL17、CXCR4是SPE患者母婴结局不良的危险因素。  相似文献   
132.
To improve our understanding of dental asymmetry, more anatomically discriminating measurements than maximum crown dimensions were used. The relation between antimeres and opponents in permanent first molar teeth of 192 twins were studied with respect to crown component measures. Several statistical methods were used to describe asymmetry and discrepancy of occluding units to correlate with developmental stress indicators such as zygosity, birth weight, and congenital disease. To varying degrees, developmental correlates are found to be associated with asymmetry. The amount of occlusal discrepancy seems to be a direct function of bilateral asymmetry. Heterogeneity of MZ-DZ total (among plus within pair) variances occurs fairly consistently for asymmetry but not for discrepancy, implying differential environmental influences between zygosities regarding asymmetry. Genetic variance estimates, designed to be unbiased by differences in environmental variances, are significant for cusp size but not for asymmetry. Our results suggest that asymmetry at the individual cusp level may be an indicator of developmental disruption and that environmental effects, particularly prenatal, may be greater for antimeric units than for occluding units.  相似文献   
133.
Background and ObjectiveIntraoperative hypotension is a common complication in general anesthesia that could result in different serious complications particularly in elderly patients. This Randomized Clinical Trial (RCT) aims to determine effective continuous infusion rate of norepinephrine to prevent intraoperative hypotension during spinal surgery under general anesthesia in elderly patients.MethodsThis RCT was conducted on elderly patients (n= 108) undergoing general anesthesia for posterior lumbar spinal fusion. The patients were randomly divided into 0.030, 0.060, and 0.090 μg.kg-1.min-1 groups of norepinephrine infusion rates. The outcomes were assessed at entrance to operation room (T0), 15 mins after anesthesia induction (T1), 60 mins following surgery (T2), and immediately after surgery (T3). The intraoperative and postoperative complications and rehabilitation outcomes were comparatively assessed.ResultsAll three groups significantly reduced the incidence of delayed wound healing (0.030 vs. 0.060 vs. 0.090 μg.kg-1.min-1; 33.3% vs. 10% vs. 10%, P=0.024) and wound infection (26.7% vs. 6.7% vs. 6.7%, P=0.031). Intraoperative total fluid volume and colloids volume in the 0.030 group were significantly higher than 0.060 and 0.090 groups (P=0.005, P=0.003, and P=0.01, respectively). The 0.060 and 0.090 groups significantly increased mean-arterial-pressure than the 0.030 group at T2 and T3. Both 0.060 and 0.090 infusion rates significantly reduced intraoperative hypotension than 0.030 dosage (P=0.01 and P=0.003, respectively). The bradycardia incidence in the 0.090 group was significantly higher than the 0.030 (P=0.026) and 0.060 groups (P=0.038). The 0.060 group decreased the first intake by 1.4 hours (P=0.008) and first flatus by 1.1 hours (P=0.004) and postoperative hospital stay by 1 day (P=0.066).ConclusionThe 0.060 µg·kg-1·min-1 norepinephrine infusion combined with goal-directed fluid therapy exhibited adequate intraoperative management and postoperative outcomes.Clinical Trial Registration www.chictr.org.cn, identifier ChiCTR-1900021309.  相似文献   
134.
Demographic changes were recorded throughout a 12-year period for three social groups ofMacaca fascicularis in a natural population at Ketambe (Sumatra, Indonesia). We examined the prediction that females' lifetime reproductive success depended on dominance rank and group size. Average birth rate was 0.53 (184 infants born during 349 female years). For mature females (aged 8–20 yr) birth rate reflected physical condition, being higher in years with high food availability and lower in the year following the production of a surviving infant. High-ranking females were significantly more likely than low-ranking ones to give birth again when they did have a surviving offspring born the year before (0.50 vs 0.26), especially in years with relatively low food availability (0.37 vs 0.10). Controlled comparisons of groups at different sizes indicate a decline in birth rate with rroup size only once a group has exceeded a certain size. The dominance effect on birth rate tended to be strongest in large groups. Survival of infants was rank-dependent, but the survival of juveniles was not. There was a trend for offspring survival to be lower in large groups than in mid-sized or small groups. However, rank and group size interacted, in that rank effects on offspring survival were strongest in large groups. High-ranking females were less likely to die themselves during their top-reproductive years, and thus on average had longer reproductive careers. We estimated female lifetime reproductive success based on calculated age-specific birth rates and survival rates. The effects of rank and group size (contest and scramble) on birth rate, offspring survival, age of first reproduction for daughters, and length of reproductive career, while not each consistently statistically significant, added up to substantial effects on estimated lifetime reproductive success. The group size effects explain why large groups tend to split permanently. Since females are philopatric in this species, and daughters achieve dominance rank positions similar to their mother, a close correlation is suggested between the lifetime reproductive success of mothers and daughters. For sons, too, maternal dominance affected their reproductive success: high-born males were more likely to become top-dominant (in another group). These data support the idea that natural selection has favored the evolution of a nepotistic rank system in this species, even if the annual benefits of dominance are small.  相似文献   
135.
西双版纳热带雨林地栖小兽群落的初步研究   总被引:5,自引:1,他引:4  
吴德林  奉勇 《兽类学报》1997,17(3):227-231
西双版纳热带雨林地栖小兽群落的初步研究APRELIMINARYSTUDYONGROUND┐DWELLINGSMALLMAMMALCOMMUNITYINTROPICALRAINFORESTOFXISHUANGBANNA西双版纳热带森林地处热带东南亚北...  相似文献   
136.
Unmeasured confounders are a common problem in drawing causal inferences in observational studies. VanderWeele (Biometrics 2008, 64, 702–706) presented a theorem that allows researchers to determine the sign of the unmeasured confounding bias when monotonic relationships hold between the unmeasured confounder and the treatment, and between the unmeasured confounder and the outcome. He showed that his theorem can be applied to causal effects with the total group as the standard population, but he did not mention the causal effects with treated and untreated groups as the standard population. Here, we extend his results to these causal effects, and apply our theorems to an observational study. When researchers have a sense of what the unmeasured confounder may be, conclusions can be drawn about the sign of the bias.  相似文献   
137.
Many randomized experiments suffer from noncompliance. Some of these experiments, so-called encouragement designs, can be expected to have especially large amounts of noncompliance, because encouragement to take the treatment rather than the treatment itself is randomly assigned to individuals. We present an extended framework for the analysis of data from such experiments with a binary treatment, binary encouragement, and background covariates. There are two key features of this framework: we use an instrumental variables approach to link intention-to-treat effects to treatment effects and we adopt a Bayesian approach for inference and sensitivity analysis. This framework is illustrated in a medical example concerning the effects of inoculation for influenza. In this example, the analyses suggest that positive estimates of the intention-to-treat effect need not be due to the treatment itself, but rather to the encouragement to take the treatment: the intention-to-treat effect for the subpopulation who would be inoculated whether or not encouraged is estimated to be approximately as large as the intention-to-treat effect for the subpopulation whose inoculation status would agree with their (randomized) encouragement status whether or not encouraged. Thus, our methods suggest that global intention-to-treat estimates, although often regarded as conservative, can be too coarse and even misleading when taken as summarizing the evidence in the data for the effects of treatments.  相似文献   
138.
This article contributes to the field of anthropological pedagogy, adding to recent articles regarding needed change in anthropology teaching methods. All have in common the practice of anthropology in the classroom. The author used the theory of optimal foraging to encourage students to operationalize human behavior. The economic benefit that students reaped warrants discussion. Students rapidly and measurably improved several areas of their lifestyle including health, finance, and home. Pursuing an anthropology degree thus becomes a personal journey.  相似文献   
139.
A discrete-time Markov chain model, a continuous-time Markov chain model, and a stochastic differential equation model are compared for a population experiencing demographic and environmental variability. It is assumed that the environment produces random changes in the per capita birth and death rates, which are independent from the inherent random (demographic) variations in the number of births and deaths for any time interval. An existence and uniqueness result is proved for the stochastic differential equation system. Similarities between the models are demonstrated analytically and computational results are provided to show that estimated persistence times for the three stochastic models are generally in good agreement when the models satisfy certain consistency conditions.  相似文献   
140.
The paper by La Vaque and Rossiter recommends that placebo-controlled trials only be conducted when best proven treatments are not available. In this comment, I review evidence suggesting that identifying best proven treatments is a complex task involving many variables and that making such a decision entails many real-world difficulties.  相似文献   
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