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51.
目的:研究FRD特殊染色技术(FRD)在宫颈疾病筛查中的结果情况,为临床诊疗提供依据。方法:选取2015年5月到2016年5月我院就诊宫颈疾病筛查者306例,对所有患者进行FRD和液基细胞学检测,两种检测有一项提示阳性则行阴道镜病理检测,以病理检测为标准,比较两种检测方法诊断价值。结果:宫颈癌前病变和宫颈癌筛查中两种检测方法敏感度分别为87.6%、84.0%,特异性分别为69.0%、63.3%,诊断符合率分别为79.7%、75.8%,阳性预测值分别为79.2%和78.4%,阴性预测值分别为81.7%和71.4%,Kappa值为0.56和0.48,比较差异无统计学意义(P0.05)。结论:FRD与液基细胞学检测筛查宫颈癌前病变和宫颈癌效果相似,但是FRD操作简便,值得在临床上应用。  相似文献   
52.
依照《第四次全国中药资源普查(试点)实施方案》调查福建省沙县中药资源本底情况,对一般种类进行普查,对重点种类进行样方、样线调查,并与第三次中药资源普查结果进行比较。调查表明,第四次中药资源普查中,沙县药用植物有180科638属1032种,其中重点种类92种,特色种类41种,显著高于第三次中药资源普查结果。沙县药用植物资源丰富,应合理保护、开发利用药用资源,带动全县中药材产业发展。  相似文献   
53.
Annual internal growth banding of Arctica islandica has shown that the species has a surprising longevity of up to 149 years as stated by THOMPSON , JONES and DREIBELBIS (1980). The authors have compiled 100 values of valve height against age as reproduced in Figure 1. Visually gained growth curves have been added for single specimens that leave some doubt as to the existence of an inflexion point. In this paper a cross-sectional evaluation of growth behaviour is carried out with nine funtions using nonlinear regressions. Five growth functions yield almost equally good results with a final valve height just below 100 mm. An inflexion point is either present in early youth or lacking altogether, depending on the growth function used.  相似文献   
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55.
We propose a stratified product limit estimator and compare the asymptotic results with those of the unstratified version. When the censoring mechanisms are unequal for different strata, the unstratified version may overestimate the total survival rate of a heterogeneous population. A numerical example in cardiac surgery is examined to demonstrate that this situation does occur in real applications. This overestimation also can be elucidated heuristically by some redistribution schemes for the censored data.  相似文献   
56.
This paper presents a model of a dynamic vaccination game in a population consisting of a collection of groups, each of which holds distinct perceptions of vaccinating versus non-vaccinating risks. Vaccination is regarded here as a game due to the fact that the payoff to each population group depends on the so-called perceived probability of getting infected given a certain level of the vaccine coverage in the population, a level that is generally obtained by the vaccinating decisions of other members of a population. The novelty of this model resides in the fact that it describes a repeated vaccination game (over a finite time horizon) of population groups whose sizes vary with time. In particular, the dynamic game is proven to have solutions using a parametric variational inequality approach often employed in optimization and network equilibrium problems. Moreover, the model does not make any assumptions upon the level of the vaccine coverage in the population, but rather computes this level as a final result. This model could then be used to compute possible vaccine coverage scenarios in a population, given information about its heterogeneity with respect to perceived vaccine risks. In support of the model, some theoretical results were advanced (presented in the appendix) to ensure that computation of optimal vaccination strategies can take place; this means, the theory states the existence, uniqueness and regularity (in our case piecewise continuity) of the solution curves representing the evolution of optimal vaccination strategies of each population group.  相似文献   
57.
The ease with which genotyping technologies generate tremendous amounts of data on research participants has been well chronicled, a feat that continues to become both faster and cheaper to perform. In parallel to these advances come additional ethical considerations and debates, one of which centers on providing individual research results and incidental findings back to research participants taking part in genetic research efforts. In 2006 the Industry Pharmacogenomics Working Group (I‐PWG) offered some ‘Points‐to‐Consider’ on this topic within the context of the drug development process from those who are affiliated to pharmaceutical companies. Today many of these points remain applicable to the discussion but will be expanded upon in this updated viewpoint from the I‐PWG. The exploratory nature of pharmacogenomic work in the pharmaceutical industry is discussed to provide context for why these results typically are not best suited for return. Operational challenges unique to this industry which cause barriers to returning this information are also explained.  相似文献   
58.
利用SNP数据检测肿瘤细胞染色体拷贝数变异是癌症相关研究的一个热点,目前已有多种方法可以通过分析SNP array数据检测染色体拷贝数。然而在某些情况下,这些检测方法检测结果与真实拷贝数具有一定错误率。目前并没有方法研究预测结果发生错误的规律。本文分别分析了GPHMM,ASCAT两种检测方法结果信息熵与检测正确率的关系,发现检测正确率与信息熵存在很强的相关性。通过对比不同肿瘤细胞比例下信息熵与正确率关系,本文发现随着肿瘤细胞比例的增大,检测结果信息熵平均值增大,方差减小;同时平均检测正确率也越来越大,方差显著减小。这些结果显示信息熵的大小可以反映出检测结果正确率的高低。最后,本文以高肿瘤细胞比例下拷贝数检测结果为例,研究了在变异类型单一,信息熵小的情况下,染色体倍性检测的正确率。结果表明信息熵可以作为衡量检测结果可信度的指标:即信息熵越高,检测结果越可信。  相似文献   
59.
Allele frequencies for 15 short tandem repeat (STR) loci (D8S1179, D21S11, D7S820, CSFIPO, D3S1358, TH01, D13S317, D16S539, D2S1338, D19S433, vWA, TPOX, D18S51, D5S818, and FGA) were obtained from 7,636 unrelated individuals of Chinese Han population living in Qinghai and Chongqing, China. Totally 206 alleles were observed, with the corresponding allele frequencies ranging from 0.0001-0.4982. Chi-square test showed that all of the STR loci agreed with the Hardy-Weinberg equilibrium. We also compared our data with previously published population data of other ethnics or areas. The results are valuable for human identification and paternity testing in Chinese Han population.  相似文献   
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