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The Working Party on Safety in Biotechnology of the European Federation of Biotechnology has proposed a classification of microorganisms that cause diseases in plants. In this paper appropriate safety levels are proposed for these classes of microorganisms in order to ensure that research, development and industrial fermentation work with plant pathogens will limit the risk of outbreaks of diseases in crops that could result from work with such microorganisms when they are cultivated in laboratories, glasshouses and biotechnology installations.Co-opted: J. Dähne, J. Drozd, M. Lemattre, I. M. Smith , E. M. A. WaterschootA Report prepared by the Working Party on Safety in Biotechnology of the European Federation of Biotechnology (EFB)
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It has been often stated that the overall pattern of human maternal lineages in Europe is largely uniform. Yet this uniformity may also result from an insufficient depth and width of the phylogenetic analysis, in particular of the predominant western Eurasian haplogroup (Hg) H that comprises nearly a half of the European mitochondrial DNA (mtDNA) pool. Making use of the coding sequence information from 267 mtDNA Hg H sequences, we have analyzed 830 mtDNA genomes, from 11 European, Near and Middle Eastern, Central Asian, and Altaian populations. In addition to the seven previously specified subhaplogroups, we define fifteen novel subclades of Hg H present in the extant human populations of western Eurasia. The refinement of the phylogenetic resolution has allowed us to resolve a large number of homoplasies in phylogenetic trees of Hg H based on the first hypervariable segment (HVS-I) of mtDNA. As many as 50 out of 125 polymorphic positions in HVS-I were found to be mutated in more than one subcluster of Hg H. The phylogeographic analysis revealed that sub-Hgs H1*, H1b, H1f, H2a, H3, H6a, H6b, and H8 demonstrate distinct phylogeographic patterns. The monophyletic subhaplogroups of Hg H provide means for further progress in the understanding of the (pre)historic movements of women in Eurasia and for the understanding of the present-day genetic diversity of western Eurasians in general.  相似文献   
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Isolated human populations represent good candidates for studying genetic and environmental causes of common complex diseases because of their decreased genetic and environmental diversity. The possibility of inexpensive and reliable detection of disease prevalence in such populations is therefore of considerable importance, as comprehensive routine health data and disease registries are rarely available in these populations. In this study, we validated the performance of the WHO Rose Angina Questionnaire (RQ) in measuring the burden of coronary heart disease (CHD) in 9 settlements in these Croatian Adriatic islands. CHD was defined as myocardial infarction (MI) diagnosed by a specialist in the local general hospital, or angina pectoris (AP) by a local general practitioner (GP). The true prevalence of CHD in 1,001 adult persons was 10.5%. The results of the RQ screening based on the first 3, 5 and 6 questions were compared with medical record of CHD. Increasing the number of RQ questions from 3 to 6 resulted in decreasing test sensitivity (from 59.0% to 30.5%) and increasing test specificity (from 86.3% to 93.0%) in the prediction of true CHD status. CHD prevalence was overestimated by 76% when subset of the first 3 questions of RQ was used and by 25% when the first 5 questions were used. However, it was underestimated by 10% when the first 6 questions were used. We conclude that RQ is a useful screening method for measuring burden of CHD in isolate human populations, and that the result based on the first 6 questions is a good approximation of the true CHD prevalence in the population, although it should be considered a slight underestimate.  相似文献   
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Origin and diffusion of mtDNA haplogroup X   总被引:10,自引:0,他引:10  
A maximum parsimony tree of 21 complete mitochondrial DNA (mtDNA) sequences belonging to haplogroup X and the survey of the haplogroup-associated polymorphisms in 13,589 mtDNAs from Eurasia and Africa revealed that haplogroup X is subdivided into two major branches, here defined as “X1” and “X2.” The first is restricted to the populations of North and East Africa and the Near East, whereas X2 encompasses all X mtDNAs from Europe, western and Central Asia, Siberia, and the great majority of the Near East, as well as some North African samples. Subhaplogroup X1 diversity indicates an early coalescence time, whereas X2 has apparently undergone a more recent population expansion in Eurasia, most likely around or after the last glacial maximum. It is notable that X2 includes the two complete Native American X sequences that constitute the distinctive X2a clade, a clade that lacks close relatives in the entire Old World, including Siberia. The position of X2a in the phylogenetic tree suggests an early split from the other X2 clades, likely at the very beginning of their expansion and spread from the Near East.  相似文献   
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The aim of this study was to investigate the prevalence of learning disability (LD) in isolate populations with different inbreeding coefficients (F). Prevalence of LD and F were determined in 10 villages from five Croatian islands: Brac, Hvar, Korcula, Lastovo and Susak. For the purpose of this study, LD was defined as the inability to attend the public school system. As the elementary schools (grade 1-8) in the place of the study are both public and compulsory, the assessment of child's inability to attend the school is performed at the age of six. This is required by all children in the country based on standard set of tests of cognitive performance defined by the Ministry of Education and Culture of the Republic of Croatia. The average inbreeding coefficients in each village population (F) were estimated in a random sample of 20-30% adults in each of the 10 villages based on 4 ancestral generations and using Wright's path method. Prevalence of LD ranged from 0.43% to 2.47%, and the inbreeding coefficients ranged from 0.8% to 4.9%. The Pearson's correlation coefficient between F and LD prevalence was 0.80 (p < 0.01). Although the relative risk per 5% inbreeding appeared very high (about 10), the absolute risk only increased from 0.18% to 1.77%. The genetic effect of inbreeding (GEI) was approximately 0.69% and the population-attributable fraction 76.6%. A review of the literature and the results of this study lead to a conclusion that a very large number of predominantly recessive genetic factors might mediate the genetic susceptibility to various forms of LD in these populations.  相似文献   
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Genetic diversity and forensic parameters based on 15AmpFlSTR Identifiler short tandem repeat (STR) loci (D8S1179, D21S11, D7S820, CSF1PO, D3S1358, TH01, D13S317, D16S539, D2S1338, D19S433, vWA, TPOX, D18S51, D5S818 and FGA) were evaluated in a sample of 101 unrelated, autochthonous adults from Montenegro. After applying Bonferroni correction, the agreement with Hardy-Weinberg equilibrium (HWE) was confirmed for all loci with the exception of D5S818 (chi2 test) and D21S11 (exact test). The combined power of discrimination (PD) and the combined power of exclusion (PE) for the 15 studied loci were 0.9999999999999999844 and 0.99999382, respectively. According to measures of within-population genetic diversity, D2S1338, D18S51 and FGA may be considered as the most variable and most informative markers for forensic testing and population genetic analyses out of the 15 analysed loci in a population of Montenegro. D5S818 showed to be the least variable and together with TPOX, the least informative. Interpopulation comparisons were carried out and levels of genetic differentiation between population of Montenegro and five South-eastern European populations (Kosovo Albanians, Serbians from Vojvodina province, Macedonians, Bosnians and Croatians) were evaluated. The most differentiated population in relation to Montenegro is a population of Kosovo Albanians as suggested by both AMOVA and coefficients of genetic differentiation (F(ST) and R(ST)).  相似文献   
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