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111.
Denaturing high-performance liquid chromatography (DHPLC) has been used for rapid and accurate DNA mutation analysis; to extend the DNA fragment lengths analysis. Recently, polymorphism in polyglutamine-coding region of Amplified In Breast cancer gene 1 (AIB1) was analyzed as an independent genetic risk factor influencing breast cancer onset in carriers of mutation in breast cancer predisposing gene 1 (BRCA1). We have implemented efficient, cost-effective and rapid method for analysis of the AIB1 polyglutamine repeat polymorphism based on DHPLC analysis (WAVE system) of unlabeled PCR products. This strategy can be useful for genotyping of other trinucleotide repeat polymorphisms using DHPLC in medium/high throughput settings. 相似文献
112.
Radwan J 《Experimental & applied acarology》2007,42(3):151-158
Whether benefits of mate choice accrued by females outweigh costs associated with sexual selection remains largely unresolved.
The ‘good genes’ perspective, posing that mate choice benefits females genetically has been challenged by the arguments that
sexual selection is driven mostly by direct costs and inter-sexual conflict. Here, I present an overview of experimental tests
of predictions of good genes and sexual conflict mechanisms in the bulb mite Rhizoglyphus robini. 相似文献
113.
E. David P. Boudry A. Tanguy J.F. Samain 《Journal of experimental marine biology and ecology》2007,349(2):272-283
Large-scale mortality events have been observed in Pacific oyster Crassostrea gigas on the west coast of France since the early 1980s, particularly during summer. In order to understand the causes of this mortality, two generations of oysters from single-pair matings were studied in three sites on the French Atlantic coast (Baie-des-Veys, Auray and Ronce-les-Bains). The present paper examines the role of two candidate genes in the susceptibility of oysters to summer mortality, and the selective pressure exerted by such mortality on their polymorphism. Glutamine synthetase (amino-acid metabolism) and delta-9 desaturase (lipid metabolism) genes were studied in the successive generations, using polymerase chain reaction single-strand conformation polymorphism (PCR-SSCP). Observed and expected genotypic frequencies were compared. Three different alleles were detected for the glutamine synthetase gene and two for delta-9 desaturase. Allele C of glutamine synthetase seemed to be counter-selected in some second generation families. Allele B of delta-9 desaturase gene was potentially counter-selected at Auray in the families showing higher mortality, and strong selection against BB homozygotes was observed. These observations led us to conclude that any selective effect of summer mortality on allele C of glutamine synthetase gene or allele B of delta-9 desaturase gene could be mediated either directly or via linkage to other loci involved in physiological pathways affecting susceptibility. 相似文献
114.
115.
We investigate the relationship between habitat heterogeneity and morphological variation in the Caribbean coral species-complex, Madracis pharensis/decactis. This complex showed strong but incomplete morphospecies habitat-matching on a small spatial scale. We find that only one Madracis morphospecies dominates in environments consisting of either few vertical or few horizontal habitats, whereas in environments consisting of a mixture of horizontal and vertical habitats both morphospecies are common. We demonstrate that the observed patterns of morphospecies habitat-matching cannot be explained by a pure polyphenic model, where morphological variants are induced by a genotype-by-environment interaction at their settling site. Instead, we suggest that habitat-matching results in whole or in part from genetically predetermined factors. We present support for the hypothesis that this pattern of habitat-matching is due to habitat- and morphospecies-specific selective factors. Our study describes how a variable environmental factor, i.e. habitat distribution, has a non-linear effect on the spatial distribution of these morphospecies, thereby influencing the genetic organization of the Madracis coral complex at the ~+1–10 km spatial scale. 相似文献
116.
Sexual selection theory has primarily focussed on the role of mating preferences for the best individuals in the evolution
of condition-dependent ornaments, traits that signal absolute quality. Because the most suitable mate for one individual is
not always the best for others, however, we argue that non-directional mate choice can promote the evolution of alternative
morphs that are not condition-dependent in their expression (i.e. genetic polymorphism). We list the different mate-choice
rules (i.e. all individuals have the same preference; preference depends on the chooser’s morph; individuals mate preferentially
with conspecifics displaying an uncommon or the most frequent morph) and review experimental studies that investigated mate
choice in natural populations of colour-polymorphic animals. Our review emphasises that although the experimental data support
the idea that sexual selection plays an important role in the evolution of genetic colour polymorphism in many different ways,
little is known about the adaptive value of each mate-choice strategy and about their implication in the evolutionary stability
of colour polymorphism. One way of solving this problem is to determine the adaptive function of colour morphs, a worthwhile
objective, because better understanding of mate-choice rules in polymorphic species should provide important insights into
sexual-selection processes and, in turn, into the maintenance of genetic variation. 相似文献
117.
Miura K Yoshiura K Miura S Shimada T Yamasaki K Yoshida A Nakayama D Shibata Y Niikawa N Masuzaki H 《Human genetics》2007,121(5):631-633
Here we provided the first genetic evidence for an association between the degree of apocrine colostrum secretion and human
earwax type. Genotyping at the earwax-type locus, rs17822931 within the ABCC11 gene, revealed that 155 of 225 Japanese women were dry-type and 70 wet-type. Frequency of women without colostrum among dry-type
women was significantly higher than that among wet-type women (P < 0.0002), and the measurable colostrum volume in dry-type women was significantly smaller than in wet-type women (P = 0.0341). 相似文献
118.
119.
Different evolutionary fates of recently integrated human and chimpanzee LINE-1 retrotransposons 总被引:4,自引:0,他引:4
The long interspersed element-1 (LINE-1 or L1) is a highly successful retrotransposon in mammals. L1 elements have continued to actively propagate subsequent to the human–chimpanzee divergence, 6 million years ago, resulting in species-specific inserts. Here, we report a detailed characterization of chimpanzee-specific L1 subfamily diversity and a comparison with their human-specific counterparts. Our results indicate that L1 elements have experienced different evolutionary fates in humans and chimpanzees within the past 6 million years. Although the species-specific L1 copy numbers are on the same order in both species (1200–2000 copies), the number of retrotransposition-competent elements appears to be much higher in the human genome than in the chimpanzee genome. Also, while human L1 subfamilies belong to the same lineage, we identified two lineages of recently integrated L1 subfamilies in the chimpanzee genome. The two lineages seem to have coexisted for several million years, but only one shows evidence of expansion within the past three million years. These differential evolutionary paths may be the result of random variation, or the product of competition between L1 subfamily lineages. Our results suggest that the coexistence of several L1 subfamily lineages within a species may be resolved in a very short evolutionary period of time, perhaps in just a few million years. Therefore, the chimpanzee genome constitutes an excellent model in which to analyze the evolutionary dynamics of L1 retrotransposons. 相似文献
120.
Xu Han Lixuan Gui Bing Liu Jing Wang Yaru Li Xiayun Dai Jun Li Binyao Yang Gaokun Qiu Jing Feng Xiaomin Zhang Tangchun Wu Meian He 《BMC genetics》2015,16(1)