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61.
Pink salmon spawners introduced into the White Sea basin (the Umba River) were compared to the spawners from the basin of the Sea of Okhotsk (the Ola River) using restriction analysis of two fragments of mitochondrial DNA (mtDNA). One of the fragments included genes ND5/ND6, the other, the cytochrome b gene and the D-loop. It was found that mtDNA variation and diversity at the earlier examined nuclear allozyme genes significantly decreased in the odd broodline of pink salmon 8 years after the introduction. The haplotype diversity in the even broodline was considerably lower than in the odd broodline exhibiting virtually no change two generations after the introduction. Based on the results obtained, a possible role of these changes in adaptation of White Sea pink salmon from the odd broodline to the new environment is discussed.  相似文献   
62.
The frequency of rare electrophoretic protein variants was studied in children with congenital anomalies. The stated frequency (1.07 X 10(-3] proved to be ten-fold higher than in the control group of newborns (1.09 X 10(-4). This difference was mainly due to rare variants of monomorphic proteins. The data obtained confirm the assumption of a functional importance of monomorphic protein loci.  相似文献   
63.
Plasma Physics Reports - The experiments at the FT-2 tokamak are described that were focused on clearing up the role of the parametric decay instabilities in decreasing the generation efficiency of...  相似文献   
64.
MALINA is a web service for bioinformatic analysis of whole-genome metagenomic data obtained from human gut microbiota sequencing. As input data, it accepts metagenomic reads of various sequencing technologies, including long reads (such as Sanger and 454 sequencing) and next-generation (including SOLiD and Illumina). It is the first metagenomic web service that is capable of processing SOLiD color-space reads, to authors’ knowledge. The web service allows phylogenetic and functional profiling of metagenomic samples using coverage depth resulting from the alignment of the reads to the catalogue of reference sequences which are built into the pipeline and contain prevalent microbial genomes and genes of human gut microbiota. The obtained metagenomic composition vectors are processed by the statistical analysis and visualization module containing methods for clustering, dimension reduction and group comparison. Additionally, the MALINA database includes vectors of bacterial and functional composition for human gut microbiota samples from a large number of existing studies allowing their comparative analysis together with user samples, namely datasets from Russian Metagenome project, MetaHIT and Human Microbiome Project (downloaded fromhttp://hmpdacc.org). MALINA is made freely available on the web athttp://malina.metagenome.ru. The website is implemented in JavaScript (using Ext JS), Microsoft .NET Framework, MS SQL, Python, with all major browsers supported.  相似文献   
65.
The data are presented on distribution of subtypes and rare variants of Pi system for Moscow population. Serum samples were obtained from 210 families of healthy newborn (father-mother-newborn) from several Moscow maternity hospitals. Phenotypes of alpha 1-antitrypsin were detected by isoelectric focusing in ultrathin layer polyacrylamide gel with the range 3.5-6. In this study 5 common PiM subtypes (except M3M3) were found. The observed distribution of Pi subtypes shows a good agreement with the Hardi-Weinberg equation. The gene frequencies of the subtypes estimated for Moscow population were as follows: PiM1-0.7662, PiM2-0.1779, PiM3-0.0398. They did not show any difference from the corresponding frequencies in other European populations. In the course of our studies, some rare phenotypes, such as MS, MZ, FM and IM that were observed in most European populations, were detected. Furthermore, a very rare variant (MT) which had been only once revealed in European population, was found. The total gene frequency of all rare variants was 0.0162.  相似文献   
66.
Distribution of individual heterozygosity (the number of heterozygous loci per individual), frequencies of genotypes formed by paired combinations of 5 loci and values of linkage disequilibrium between 6 blood group loci were studied both in a group of couples and single women with recurrent abortions in anamnesis, and in a group of couples and single women with normal fertility. Statistically significant deficit of highly heterozygous individuals was found in the experimental group. Marked increase of genetical variability was shown for the women with repeated abortions, as a consequence of elevation of rare genotypic paired combination frequency. Therefore, differential fertility as a component of stabilizing selection alters the distribution of complex genotypes in human populations. Differences in values of linkage disequilibrium between women with repeated abortions and those of normal fertility were not found.  相似文献   
67.
Altukhov IuP  Blank ML 《Genetika》1999,35(11):1572-1584
Genetic dynamics of population systems consisting of a finite number of small (Ne < 10(2)) semiisolated subpopulations was studied. A method of quantitative estimation of statistical parameters was developed for different types of population systems and different directions or intensities of selection. The following regularities were established: (1) optimal numbers of subpopulations, their effective size and rates of gene migration promoting continuous maintenance of genetic diversity can be chosen; (2) the genetic process in a population system is stationary only in the case of a specific structure of gene migrations corresponding to Wright's island model; (3) cyclic dynamics can stabilize the population system at high levels of gene diversity in a heterogeneous environment if gene migration and subpopulation size change in time. Similarities and differences between the concept of population system and the concept of metapopulation, which have been simultaneously proposed in Russia and abroad, are discussed in the final section.  相似文献   
68.
Polymorphism of two tumor-suppressor genes, BRCA1 and P53, was examined. DNA was extracted from blood leukocytes of the women affected with breast cancer (N = 151) and of the women with no clinical symptoms of tumor diseases (N = 191). Typing of the polymorphic variants was performed using PCR-RFLP method. It was demonstrated that the genetic structure of the patient group (taking into consideration BRCA1 and P53 polymorphic variants) differed from that of the control group. The group of genotypes, found exclusively among the patients, as well as the group of “ resistant” genotypes revealed predominantly among the controls, was described. Detection of the genotype A 1 A 1 B 1 B 1 S 1 S 1 C 1 C 1 F 1 F 1 J 2 J 2, whose frequency in control group was eight times higher than in the patient group, was an additional confirmation of the existence of “resistant” genotypes. These findings point to the association between the combinations of the BRCA1 and P53 allelic variants and the risk of breast cancer.__________Translated from Genetika, Vol. 41, No. 8, 2005, pp. 1115–1124.Original Russian Text Copyright © 2005 by Tarasov, Aslanyan, Tsyrendorzhiyeva, Garkavtseva, Lyubchenko, Altukhov, Mel’nik.  相似文献   
69.
Intra- and interspecific variability of total DNA isolated from haploid megagametophytes of coniferous species was examined using polymerase chain reaction with random primers. Based on this technique, one can with certainty detect heterozygosity at gene loci carrying null alleles and thus reveal cryptic intraspecific genetic variation. Large population samples were used. Along with random amplified polymorphic DNA, i.e., widely known fragments (amplicons) polymorphic within a species, we found invariant loci lacking individual or geographic variability but differentiating species within genera and other taxa. This DNA was termed RAMD (random amplified monomorphic DNA) to distinguish it from polymorphic DNA. Our findings suggest that genetic monomorphism of species and the dual structure of the eukaryotic genome can be detected at the DNA level as was previously shown for protein gene markers.  相似文献   
70.
Genetic demographic characteristics and immunogenetic markers (blood groups ABO, Rhesus, MNSs, P, Duffy, Kidd, and Kell) have been studied in a group of 132 Russian cosmonauts and test subjects (CTSG). Analysis of pedigrees has shown a high exogamy in the preceding generations: almost half of the subjects have mixed ethnic background. According to the results of genetic demographic analysis, a sample from the Moscow population was used as control group (CG). Comparison between the CTSG and CG has demonstrated significant differences in genotype frequencies for several blood group systems. The CTSG is characterized by a decreased proportion of rare interlocus genotypic combinations and an increased average heterozygosity. Analysis of the distributions of individual heterozygosity for loci with codominant expression of alleles has shown that the carriers of highly heterozygous genotypes are more frequent in the CTSG. Taking into account that the CTSG has been thoroughly selected from the general population, it is concluded that heterozygosity is related to successful adaptation to a space flight.  相似文献   
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