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331.
Short tandem repeat studies are powerful tools for parentage analysis and for identification of missing persons, victims of murder, and victims of mass fatalities when reference samples are unavailable. The primer in the Identifiler kit failed to amplify an allele at the D19S433 locus, producing a silent ("null") allele. The causal mutation is a base change (G>A) 32 nucleotides downstream from the 3' end of the AAGG repeats. The silent alleles are problematical in parentage analysis because when transmitted, they can cause a parent-child inconsistency that is unrelated to Mendelian genetics. The inconsistency is sometimes termed an "apparent opposite homozygosity" and it produces false evidence of nonparentage. Alternative primers were designed to amplify the D19S433 locus alleles and they detect the silent allele. Frequencies of the (no longer) silent allele were determined to be 0.0114 in 176 people from Shizuoka (Honshu) and 0.0128 in 156 people from Okinawa.  相似文献   
332.
亲子鉴定STR突变的考虑   总被引:4,自引:0,他引:4  
亲子鉴定中常会发生STR(short tandem repeats,短串联重复)突变的情况。突变对亲子关系的判定会造成困扰。对STR突变规律和亲子鉴定中所遇到的STR突变问题、突变的判定、突变下非父排除率和父权指数的计算以及需与突变区分的情形等问题进行综述和讨论。  相似文献   
333.
Owing to a wrong name registered on ID card, the identity of a businessman who had been dead and cremated was suspected, which led his son failed to get legacy. In order to prove the parenthood, the son submitted the gastric cancer tissues surgically removed and embedded in a paraffin block as DNA source for paternity test. After extracting DNA with QIAamp DNA Blood Mini Kit, the 16 STR loci was amplified by two commercial kits of Sinofiler® (ABI)and Powerplex 16 (Promega), respectively. Both of the STR profiles were similarly showing allelic imbalance pattern at some loci and an additional allele at locus D18S51. The cancerous tissues and adjacent normal tissues were then partitioned off from each other by microscopic analysis of H.E. stained sections and followed by DNA extracting and STR typing, respectively. The allelic alteration could not be found in normal tissues whereas it did in cancerous tissues whose STR profile showed complete loss of one allele (LOH) at loci D13S317 (allele 11 was lost), partial loss of one allele (pLOH) at loci D21S11, D7S820, D19S433, vWA, D12S391 and Amelogein and occurrence of an additional allele (allele 20 was added) at locus D18S51. The results demonstrated that the Paraffin Embedded cancer Tissue used as DNA source for forensic identification is possibly questionable because of their microsatellite instability (MSI) or loss of heterozygosity. It was suggested to partition the normal tissues from the cancer tissues by microscopic evaluation first and then analyzing DNA separately. Comparing the STRs profile of normal tissue with the son's blood sample, the final conclusion was acquired that the donor of the paraffin embedded tissues is the biological father of the son.  相似文献   
334.
Abstract: Blood‐borne viral infections are widespread among injecting drug users; however, it is difficult to include these patients in serological surveys. Therefore, we developed a national surveillance program based on postmortem testing of persons whose deaths were drug related. Blood collected at autopsy was tested for anti‐HBc, anti‐HBs, anti‐hepatits C virus (HCV), or anti‐human immunodeficiency virus (HIV) antibodies using commercial kits. Subsets of seropositive samples were screened for viral genomes using sensitive in‐house and commercial polymerase chain reaction (PCR) assays. Hepatitis B virus (HBV) DNA was detected in 20% (3/15) of anti‐HBc‐positive/anti‐HBs‐negative samples, HCV RNA was found in 64% (16/25) of anti‐HCV‐positive samples, and HIV RNA was detected in 40% (6/15) of anti‐HIV‐positive samples. The postmortem and antemortem prevalences of HBV DNA and HCV RNA were similar. Postmortem HIV RNA testing was less sensitive than antemortem testing. Thus, postmortem PCR analysis for HBV and HBC infection is feasible and relevant for demonstrating ongoing infections at death or for transmission analysis during outbreaks.  相似文献   
335.
目的介绍一种亲权指数(paternity index,PI)计算的新方法。方法假定亲代的等位基因都要经过一个转变的过程才发生分离并遗传给子代。每个亲代的等位基因与子代相同时,其转变概率为1;当不相同时,其转变概率为0。且每个亲代的等位基因都有1/2的机会遗传给子代。据此,可以计算出孩子从争议父或母亲获得等位基因的概率。而随机男子提供等位基因给孩子的概率为等位基因频率。相应地算出PI值公式中的分子(X)和分母(Y)值。结果推导得到了一个能够计算三联体、二联体和失踪孩子案PI值的通用计算公式。结论本PI计算公式在亲子鉴定PI值计算上具有实用价值。  相似文献   
336.
目的对标准三联体亲子鉴定的非父排除率(PE)进行公式推导和实验验证。方法基于PE定义自行推导公式:PE=sum(P_i~2(1-P_i)~2)from i=1 to n+sum(P_iP_j(1-P_i)~3)from ij to n+sum(P_iP_j(1-P_j)~3)from ij to n+sum(P_iP_j(P_i+P_j)(1-P_i-P_j)~2)from ij to n。将该公式与前人报道的5个公式(1)~(5)进行对比,计算AGCU EX20系统19个常染色体STR基因座的PE值。根据1 000例单亲样本和1 000个无关个体样本设计真实实验,计算PE真实实验值。以随机模拟法产生1 000万对模拟亲母子和1 000万个随机个体,设计模拟实验计算PE模拟实验值。在19个基因座,统计各基因座的等位基因频率之和(S),将PE的公式值、真实实验值和模拟实验值进行对比。结果当S=1时,公式(1)、(2)、(5)、(6)计算结果完全一致,且符合真实和模拟双重实验验证。当S≠1时,公式(1)、(2)、(5)、(6)计算结果有较小误差。公式(3)、(4)的计算结果有较大误差。结论本研究推导的公式(6)与经典公式(1)、(2)、(5)均可用于标准三联体亲子鉴定。S值对PE公式计算有一定影响。  相似文献   
337.
目的探讨二联体亲权鉴定时存在的风险。方法选取22组经Goldeneye~(TM) 20A试剂盒检测后只有一个或没有不符合基因座的无关个体对构建假想家系。对其增加检测STRtyper-10G和/或AGCU 21+1 STR系统直至所有组不符合基因座个数大于3个,累积父权指数(CPI)不大于0.000 1。以三种规则:(1)不符合基因座数大于3个;(2)CPI值小于0.000 1;(3)同时满足(1)和(2),作为排除依据,使用不同数量的基因座(19个、26个、39个和46个)进行检测,讨论无关个体对的排除情况是否存在差异。结果 22组无关个体对,使用19个基因座和39个基因座以上的检测系统达到排除结果的分别为0组和22组。结论二联体亲子鉴定,使用19个基因座进行检测仍存在结果错判,39个基因座以上的检测系统能更有效的避免二联体的鉴定风险。  相似文献   
338.
This study presents a wavelet analysis of resultant velocity features belonging to genuine and forged groups of signature sample. Signatures of individuals were initially classified based on visual human perceptions of their relative sizes, complexities, and legibilities of the genuine counterparts. Then, the resultant velocity was extracted and modeled through wavelet analysis from each sample. The wavelet signal was decomposed into several layers based on maximum overlap discrete wavelet transform (MODWT). Next, the zero crossing rate features were calculated from all the high wavelet sub‐bands. A total of seven hypotheses were then tested using a two‐way ANOVA testing methodology. Of these, four hypotheses were conducted to test for significance differences between distributions. In addition, three hypotheses were run to provide test for interaction between two factors of signature authentication versus perceived classification. The results demonstrated that both feature distributions belonging to genuine and forged groups of samples cannot be distinguished by themselves. Instead, they were significantly different under the influence of two other inherent factors, namely perceived size and legibility. Such new findings are useful information particularly in providing bases for forensic justifications in establishing the authenticity of handwritten signature specimens.  相似文献   
339.
Mehlman and Li offer a framework for approaching the bioethical issues raised by the military use of genomics that is compellingly grounded in both the contemporary civilian and military ethics of medical research, arguing that military commanders must be bound by the two principles of paternalism and proportionality. I agree fully. But I argue here that this is a much higher bar than we may fully realize. Just as the principle of proportionality relies upon a thorough assessment of harms caused and military advantage gained, the use of genomic research, on Mehlman and Li''s view, will require an accurate understanding of the connection between genotypes and phenotypes – accurate enough to ameliorate the risk undertaken by our armed forces in being subject to such research. Recent conceptual work in evolutionary theory and the philosophy of biology, however, renders it doubtful that such knowledge is forthcoming. The complexity of the relationship between genotypic factors and realized traits (the so-called ‘G→P map’) makes the estimation of potential military advantage, as well as potential harm to our troops, incredibly challenging. Such fundamental conceptual challenges call into question our ability to ever satisfactorily satisfy the demands of a sufficiently rigorous ethical standard.  相似文献   
340.
本文以浓缩的唾液为样本,用聚丙烯酰胺凝胶电泳的方法,调查了338名辽宁地区汉族人群的PmF、PmS和Ps型的分布。其基因频率为Ps~10.391、Ps~20.064、Ps°.545;PmF~+0.47、PmF~-0.53;PmS~+0.412、PmS~-0.588。按Hardy-Weinberg法则进行吻合度检验,Ps系统的观察值与期望值高度一致(0.975相似文献   
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