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71.
CERVUS is a Windows-based software package written to infer paternity in natural populations. It offers advantages over exclusionary-based methods of paternity inference in that multiple nonexcluded males can be statistically distinguished, laboratory typing error is considered and statistical confidence is determined for assigned paternities through simulation. In this study we use a panel of 84 microsatellite markers to retrospectively determine the accuracy of statistical confidence when CERVUS was used to infer paternity in a population of red deer (Cervus elaphus). The actual confidence of CERVUS-assigned paternities was not significantly different from that predicted by simulation.  相似文献   
72.
In the study of depression, most randomized clinical trials have design features that attempt to sample from a stable patient population. One commonly used design feature is to require patients to maintain some minimum baseline symptom severity score during a placebo lead-in period. One intent of this design feature is to evaluate the behavior of patients prior to administration of active medication. If, during the lead-in period, patients do not maintain minimum symptom severity, the patients are excluded from the remainder of the study, the theory being that the excluded patients are not part of a stable patient population and hence are not likely to demonstrate efficacy of a truly effective treatment. This presentation investigates the effectiveness of a restrictive entry criterion and proposes an alternative explanation for what is usually defined as placebo response.  相似文献   
73.
Large-sample theory for parametric multiple imputation procedures   总被引:3,自引:0,他引:3  
WANG  NAISYIN; ROBINS  JAMES M. 《Biometrika》1998,85(4):935-948
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74.
We have considered a Bayesian approach for the nonlinear regression model by replacing the normal distribution on the error term by some skewed distributions, which account for both skewness and heavy tails or skewness alone. The type of data considered in this paper concerns repeated measurements taken in time on a set of individuals. Such multiple observations on the same individual generally produce serially correlated outcomes. Thus, additionally, our model does allow for a correlation between observations made from the same individual. We have illustrated the procedure using a data set to study the growth curves of a clinic measurement of a group of pregnant women from an obstetrics clinic in Santiago, Chile. Parameter estimation and prediction were carried out using appropriate posterior simulation schemes based in Markov Chain Monte Carlo methods. Besides the deviance information criterion (DIC) and the conditional predictive ordinate (CPO), we suggest the use of proper scoring rules based on the posterior predictive distribution for comparing models. For our data set, all these criteria chose the skew‐t model as the best model for the errors. These DIC and CPO criteria are also validated, for the model proposed here, through a simulation study. As a conclusion of this study, the DIC criterion is not trustful for this kind of complex model.  相似文献   
75.
目的:通过对接受假体法隆胸患者的手术前后的生命质量和自尊水平进行主观的评价,得到真实、可靠的手术效果评价结果,最终提高隆胸手术患者的满意度。方法:选取接受假体法隆胸术患者共60例,在手术之前、术后6个月使用SF-36生命质量量表和Rosenberg自尊量表进行生命质量状况和自尊状况的测量评估,并和常模进行比较。结果:接受假体法隆胸患者术前SF-36生命质量量表中社会功能(SF)和精神健康(MH)两项得分明显低于常模(P0.01);术后6个月量表中社会功能(SF)和精神健康(MH)两项水平有显著改善(P0.01);Rosenberg自尊量表显示患者术后6个月的自尊水平较术前有明显的改善(P0.001)。结论:假体法隆胸手术能使患者的生命质量得到一定程度的改善,隆胸手术对患者的自尊水平有积极的显著的影响。  相似文献   
76.
目的:探究经皮椎弓根空心螺钉微创椎体间融合治疗腰椎间盘突出的临床效果及安全性。方法:病例来源于我院2009 年12 月~2013 年12 月收治的确诊为腰椎间盘突出症的病患174 例,依据随机数字表法将其均分为观察组与对照组,每组87 例。其 中,观察组施行Quadrant微创通道经皮椎弓根空心螺钉椎间融合术,对照组施行经后入路开放性椎间融合术。评估和比较两组病 患术前和随访结束时的视觉模拟评分系统(VAS)疼痛评分与Oswestry 功能障碍指数(ODI)的变化及术后并发症的发生情况。结 果:观察组治疗前、出院时及随访一年时的VAS 评分与ODI指数与对照组比较差异均不显著(P>0.05)。观察组手术切口长度、术 后住院时间及术中出血量均明显优于对照组(P<0.01),而其手术所需时间明显长于对照组(P<0.01)。对照组患者术后出现20 例神 经根损伤(22.99%),3 例椎间隙感染(3.45%),其并发症总发生率为(26.44%),而观察组患者术后仅出现3 例神经根损伤,发生率为 3.45%,显著低于对照组(P<0.01)。结论:经皮椎弓根空心螺钉微创椎体间融合治疗的临床效果肯定,能减少对病患的创伤,控制术 后并发症的发生,具有较高的临床应用价值。  相似文献   
77.
目的:探讨脑弥漫性轴索损伤(DAI)的磁共振成像(MRI)征象及其与格拉斯哥昏迷量表评分(GCS)计分和预后的关系。方 法:回顾性分析2012 年1 月-2014 年7 月我院收集的30 例DAI 患者的临床病历资料,根据病灶累及部位分析其与GCS 计分和 临床预后的关系。结果:30 例患者共53 个病灶,17例多发病灶,13 例单发病灶;42 个病灶T1WI显示出低信号或者是等信号,11 个病灶T1WI显示为高信号;T2WI显示为高信号,FLAIR 序列以及弥散加权像(DWI)上表现出的信号更高,范围更清晰;病灶形 态呈条索状27 例,斑片状11 例,卵圆形8 例,不规则斑点状7 例;病灶未累及脑中线部位的患者临床预后优于病灶累及脑中线 部位的患者,差异有统计学意义(Z=-2.636,P=0.008),病灶累及脑中线部位的患者GCS 计分情况比未累及组严重,计分更低,差 异有统计学意义(Z=-2.519,P=0.012)。结论:DAI病灶累及脑中线部位的患者GCS计分较低、预后差,MRI检查是诊断DAI 首选 的影像学方法,临床有重要的参考价值。  相似文献   
78.
The ability of the biochemical measurements, haem iron, intramuscular fat (IMF%), moisture content, and total, soluble and insoluble collagen contents, to predict untrained consumer sensory scores both across different muscles and within the same muscle from different carcasses were investigated. Sensory scores from 540 untrained French consumers (tenderness, flavour liking, juiciness and overall liking) were obtained for six muscles; outside (m. biceps femoris), topside (m. semimembranosus), striploin (m. longissimus thoracis), rump (m. gluteus medius), oyster blade (m. infraspinatus) and tenderloin (m. psoas major) from each of 18 French and 18 Australian cattle. The four sensory scores were weighted and combined into a single score termed MQ4, which was also analysed. All sensory scores were highly correlated with each other and with MQ4. This in part reflects the fact that MQ4 is derived from the consumer scores for tenderness, juiciness, flavour and overall liking and also reflects an interrelationship between the sensory scores themselves and in turn validates the use of the MQ4 term to reflect the scope of the consumer eating experience. When evaluated across the six different muscles, all biochemical measurements, except soluble collagen, had a significant effect on all of the sensory scores and MQ4. The average magnitude of impact of IMF%, haem iron, moisture content, total and insoluble collagen contents across the four different sensory scores are 34.9, 5.1, 7.2, 36.3 and 41.3, respectively. When evaluated within the same muscle, only IMF% and moisture content had a significant effect on overall liking (5.9 and 6.2, respectively) and flavour liking (6.1 and 6.4, respectively). These results indicate that in a commercial eating quality prediction model including muscle type, only IMF% or moisture content has the capacity to add any precision. However, all tested biochemical measurements, particularly IMF% and insoluble collagen contents, are strong predictors of eating quality when muscle type is not known. This demonstrates their potential usefulness in extrapolating the sensory data derived from these six muscles to other muscles with no sensory data, but with similar biochemical parameters, and therefore reducing the amount of future sensory testing required.  相似文献   
79.
Dopamine (DA) replacement therapy continues to be the gold standard treatment for Parkinson's disease (PD), as it improves key motor symptoms including bradykinesia and gait disturbances. With time, treatment induces side effects in the majority of patients, known as L‐DOPA‐induced dyskinesia (LID), which are often studied in animals by the use of unilateral, toxin‐induced rodent models. In this study, we used the progressive, genetic PD model MitoPark to specifically evaluate bilateral changes in motor behavior following long‐term L‐DOPA treatment at three different stages of striatal DA depletion. Besides locomotor activity, we assessed changes in gait with two automated gait analysis systems and the development of dyskinetic behavior. Long‐term treatment with a moderate, clinically relevant dose of L‐DOPA (8 mg/kg) gradually produced age‐dependent hyperactivity in MitoPark mice. In voluntary and forced gait analyses, we show that MitoPark mice with severe DA depletion have distinct gait characteristics, which are normalized to control levels following long‐term L‐DOPA treatment. The cylinder test showed an age‐dependent and gradual development of bilateral LID. Significant increase in striatal FosB and prodynorphin expression was found to accompany the behavior changes. Taken together, we report that MitoPark mice model both behavioral and biochemical characteristics of long‐term L‐DOPA treatment in PD patients and provide a novel, consistent and progressive animal model of dyskinesia to aid in the discovery and evaluation of better treatment options to counteract LID.  相似文献   
80.
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