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81.
A comparison of erythrocyte markers (ABO, Rh system) gene frequencies was done by bar code diagrams in populations of variable ethnic origin. The results from missions for the development in Far East Asia (China, Indochina, New Guinea) were compared to well known gene frequencies of the populations living in other regions: inhabitants of the islands of the Pacific ocean, Europeans of New Zealand and Western Europe (France), Europeans of North America, Ameridans of Peru and Bolivia, Somalians of Africa. Polymorphism was observed in immense country very peopled, monomorphism was found in small and isolated region but polymorphism existed in tribes living in very isolated islands.  相似文献   
82.
Summary Restriction Fragment Length Polymorphisms (RFLP) have been identified between widely distant cultivars (Minsoy and Noir 1 ) of soybean Glycine max (L.) Merrill. Using as probes randomly chosen clones of DNA, one in five probes revealed a polymorphism. More than half of these polymorphisms appear to result from rearrangements of the genomic DNA. Twenty seven markers were analyzed for linkage in F2 plants. Eleven of these markers were contained in four linkage groups. Five cultivars were compared in a search for new alleles. When RFLP markers corresponding to low copy DNA were used to analyze three other cultivars — Sooty, Forrest and Mandarin (Ottawa) — few new alleles were found. Using these probes, five different markers could be used to differentiate the five cultivars. Complex probes, which correspond to repeated DNA, revealed different polymorphisms in different cultivars and a single such probe could be used to distinguish the five cultivars from each other.  相似文献   
83.
Glucose oxidase (β-d-glucose: oxygen 1-oxidoreductase, EC 1.1.3.4, GOD) was continuously released from Aspergillus sp. under mild ultrasound waves (20 kHz, 15 W). However, GOD was not released from the cells under normal conditions because of their thick wall. GOD production under ultrasound waves was optimum at pH 7.5 and 30°C and decreased with increasing ultrasonic frequency. Ultrasonic cavitation accelerated GOD release from the cells. Microscopic observation and determination of ATP and nucleic acids in the broth revealed that the mycelia were not broken during a 5 h reaction under ultrasound waves (15 W). About 10% of GOD produced in cells was released during the reaction.  相似文献   
84.

BACKGROUND:

Human leukocyte antigen (HLA) is comprised of a highly polymorphic set of genes which determines the histocompatibility of organ transplantation. The present study was undertaken to identify HLA class I and class II allele, genotype and haplotype frequencies in renal transplant recipients and donors from West Central India.

MATERIALS AND METHODS:

HLA typing was carried out using Polymerase Chain Reaction-Sequence Specific Primer in 552 live related and unrelated renal transplant recipients and donors.

RESULTS:

The most frequent HLA class I and class II alleles and their frequencies in recipients were HLA-AFNx0101 (0.1685) and AFNx0102 (0.1649), HLA-BFNx0135 (0.1322), and HLA-DR beta 1 (DRB 1)FNx0115 (0.2192), whereas in donors, these were HLA-AFNx0102 (0.1848) and AFNx0101 (0.1667), HLA-BFNx0135 (0.1359), and HLA-DRB1FNx0115 (0.2409). The two-locus haplotype statistical analysis revealed HLA-AFNx0102-B61 as the most common haplotype with the frequency of 0.0487 and 0.0510 in recipients and donors, respectively. Further, among the three locus haplotypes HLA-AFNx0133-BFNx0144-DRB1FNx0107 and HLA-AFNx0102-BFNx0161-DRB1FNx0115 were the most common haplotypes with frequencies 0.0362 and 0.0326, respectively in recipients and 0.0236 and 0.0323, respectively in donors. Genotype frequency revealed a high prevalence of genotype HLA-AFNx0102/AFNx0124 in recipients (0.058) compared to donors (0.0109) whereas low prevalence of HLA-AFNx0101/AFNx0102 in recipients (0.0435) than in donors (0.0797). The phylogenetic and principal component analysis of HLA allele and haplotype frequency distribution revealed genetic similarities of various ethnic groups. Further, case control analysis provides preliminary evidence of association of HLA-A genotype (P < 0.05) with renal failure.

CONCLUSION:

This study will be helpful in suitable donor search besides providing valuable information for population genetics and HLA disease association analysis.  相似文献   
85.
相关个体基因型联合概率分布及在身份鉴定中的应用   总被引:1,自引:0,他引:1  
从联合父系基因概率出发,得出处在同一代的多个个体的联合基因型概率,讨论两种符合我国国情的家谱图,得到同一家族内第m代独生子女之间的联合基因型概率,相应的方法可用来求多个家族、多代独生子女之间的联合基因型概率.列举了两个案例来说明相关个体的联合基因型概率在身份鉴定中的应用.  相似文献   
86.
Polymorphisms of CYP450 metabolizer enzymes and transport proteins play crucial roles in the inter‐individual variability of drug efficiency. The aim of our study was to predict the frequency of functional variants of CYP2D6, CYP2C19 and ABCB1 genes in the Hungarian population. One hundred twelve unrelated healthy subjects donated DNA sample in the study. ABCB1 C3435T and G2677T/A single‐nucleotide polymorphisms (SNPs) were determined by LightCycler polymerase chain reaction. Because only limited amount of data is available on the rare allelic variants of CYP2D6 in the European populations, our study applied an expanded set of CYP2D6 and CYP2C19 alleles by using AmpliChip test. Our results show that the CYP2D6 phenotypes were 1.9% ultra‐rapid metabolizer, 6.5% intermediate metabolizer (IM), 8.3% poor metabolizer (PM) and 83.3% extensive metabolizer (EM), and the CYP2C19 phenotypes were 1.8% PM, 31.2% IM and 67% EM. The prevalence of the commonly observed CYP2D6 and CYP2C19 alleles in our study corresponds with that of other European populations. Nevertheless, our study confirms that extending the CYP2D6 allele set with loss‐of‐function variants such as CYP2D6*7, *9, *41 is worth considering. Frequency of the wild type ABCB1 3435C was 42.8% whereas the prevelance of 2677 G was 50.4%. Although frequency data of G2677T/A SNP in the European area are limited, some discrepancies with other studies were found. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
87.
Working with weakly congruent markers means that consensus genetic structuring of populations requires methods explicitly devoted to this purpose. The method, which is presented here, belongs to the multivariate analyses. This method consists of different steps. First, single-marker analyses were performed using a version of principal component analysis, which is designed for allelic frequencies (%PCA). Drawing confidence ellipses around the population positions enhances %PCA plots. Second, a multiple co-inertia analysis (MCOA) was performed, which reveals the common features of single-marker analyses, builds a reference structure and makes it possible to compare single-marker structures with this reference through graphical tools. Finally, a typological value is provided for each marker. The typological value measures the efficiency of a marker to structure populations in the same way as other markers. In this study, we evaluate the interest and the efficiency of this method applied to a European and African bovine microsatellite data set. The typological value differs among markers, indicating that some markers are more efficient in displaying a consensus typology than others. Moreover, efficient markers in one collection of populations do not remain efficient in others. The number of markers used in a study is not a sufficient criterion to judge its reliability. "Quantity is not quality".  相似文献   
88.
In the past decade conditional autoregressive modelling specifications have found considerable application for the analysis of spatial data. Nearly all of this work is done in the univariate case and employs an improper specification. Our contribution here is to move to multivariate conditional autoregressive models and to provide rich, flexible classes which yield proper distributions. Our approach is to introduce spatial autoregression parameters. We first clarify what classes can be developed from the family of Mardia (1988) and contrast with recent work of Kim et al. (2000). We then present a novel parametric linear transformation which provides an extension with attractive interpretation. We propose to employ these models as specifications for second-stage spatial effects in hierarchical models. Two applications are discussed; one for the two-dimensional case modelling spatial patterns of child growth, the other for a four-dimensional situation modelling spatial variation in HLA-B allele frequencies. In each case, full Bayesian inference is carried out using Markov chain Monte Carlo simulation.  相似文献   
89.
A modified procedure for detection of the two alleles of equine plasminogen using Western blotting methods following polyacrylamide gel isoelectric focusing is described. Gene frequencies in 23 breeds and Equus przewalskii are provided.  相似文献   
90.
Heterogeneity of gene frequencies in the polymorphism of the third component of complement among local samples in Iraq is analysed. It appears to derive essentially from population and not from regional differences.  相似文献   
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