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101.
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Yamanaka Akihiro Beuckmann Carsten T. Willie Jon T. Hara Junko Tsujino Natsuko Goto Katsutoshi Yanagisawa Masashi Sakurai Takeshi 《Sleep and biological rhythms》2016,2(1):S57-S57
Sleep and Biological Rhythms - 相似文献
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Takashi Koyanagi Akira Nakagawa Masashi Kiyohara Hiroshi Matsui Atsushi Tsuji Florin Barla 《Bioscience, biotechnology, and biochemistry》2016,80(2):399-406
Sake is made from steamed rice, malted rice, and water. Sake production begins with the preparation of a small-scale starter (moto); the quality of moto significantly influences the flavor and richness of sake. In the traditional starter, yamahai-moto, the growth of naturally occurring lactic acid bacteria represses the putrefactive micro-organisms, whereas in the modern starter, sokujo-moto, this is achieved by adding lactic acid. In this study, the successive change in bacterial flora of yamahai-moto was analyzed by pyrosequencing 16S ribosomal RNA genes. Lactobacillus was dominant throughout the process (93–98%). Nitrate-reducing bacteria that have been generally assumed to be the first colonizers of yamahai-moto were scarcely found in the early stage, but Lactobacillus acidipiscis dominated. Lactobacillus sakei drastically increased in the middle stage. This is the first report, though one case study, to show how the early stage microbiota in Japanese yamahai-moto is varyingly controlled without nitrate-reducing bacteria using next-generation sequencing. 相似文献
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Conserved roles of fibroblast growth factor receptor 2 signaling in the regulation of inner cell mass development in bovine blastocysts
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Misato of Drosophila melanogaster and Saccharomyces cerevisiae DML1 are conserved proteins having a homologous region with a part of the GTPase family that includes eukaryotic tubulin and prokaryotic FtsZ. We characterized human Misato sharing homology with Misato of D. melanogaster and S. cerevisiae DML1. Tissue distribution of Misato exhibited ubiquitous distribution. Subcellular localization of the protein studied using anti-Misato antibody suggested that it is localized to the mitochondria. Further experiments of fractionating mitochondria revealed that Misato was localized to the outer membrane. The transfection of Misato siRNA led to growth deficiencies compared with control siRNA transfected HeLa cells, and the Misato-depleted HeLa cells showed apoptotic nuclear fragmentation resulting in cell death. After silencing of Misato, the filamentous mitochondrial network disappeared and fragmented mitochondria were observed, indicating human Misato has a role in mitochondrial fusion. To examine the effects of overexpression, COS-7 cells were transfected with cDNA encoding EGFP-Misato. Its overexpression resulted in the formation of perinuclear aggregations of mitochondria in these cells. The Misato-overexpressing cells showed low viability and had no nuclei or a small and structurally unusual ones. These results indicated that human Misato has a role(s) in mitochondrial distribution and morphology and that its unregulated expression leads to cell death. 相似文献
109.
The common yellow butterfly Eurema hecabe is widely distributed in East Asia, and is one of the most burdensome species for taxonomists due to the numerous geographic
and seasonal wing colour patterns. Moreover, within this species, individuals with a yellow wing fringe that occur in temperate
regions of Japan (Y type) proved to be biologically different from others that occur widely in subtropical regions of Japan
and all over East Asia (B type). To unveil the genetic variation within and between the two types, a total of 50 butterflies
collected at 18 geographic localities in East Asia were examined for nucleotide sequence variation of three mitochondrial
regions: cytochrome c oxidase subunit I (COI), cytochrome c oxidase subunit III (COIII) and NADH dehydrogenase subunit 5 (ND5). In addition, they were also examined for infection status
with the endosymbiotic bacteria Wolbachia. The three mitochondrial sequences consistently showed that (i) Y type and B type were highly divergent, (ii) nucleotide
variation within B type was very small although sampled from a geographically wide range, and (iii) a weak association existed
between mitochondrial DNA haplotypes and Wolbachia infection status. 相似文献
110.
Adenylate kinase (AK) is localized in sea urchin sperm flagella and embryonic cilia. To investigate sea urchin Strongylocentrotus purpuratus AK (SpAK) enzymatic characteristics, the full-length recombinant protein of 130 kDa (SpAKr) and each of its three catalytic domains were expressed in Escherichia coli. Although the full-length SpAK had high enzymatic activity, each of the three catalytic domains had no activity. The Km for ATP synthesis from ADP was 0.23 mM and the Vmax was 4.51 mumol ATP formed per minute per milligram of protein. The specific AK inhibitor, Ap5A, blocks SpAKr enzymatic activity with an IC50 of 0.53 microM. The pH optimum for SpAKr is 8.1, as compared to 7.7 for the natural SpAK. Calcium inhibits SpAKr activity in a dose-dependent manner. Although SpAKr has three cAMP-dependent protein kinase phosphorylation sites, and can be phosphorylated in vitro, the enzymatic kinetics after phosphorylation are not significantly altered. SpAK and Chlamydomonas flagellar AKs are the only AKs with three catalytic sites. Further study of the SpAKr will aid in understanding the active site of this interesting and important ATP synthase. 相似文献