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Identification, characterization, and localization of a novel kidney polycystin-1-polycystin-2 complex 总被引:9,自引:0,他引:9
Newby LJ Streets AJ Zhao Y Harris PC Ward CJ Ong AC 《The Journal of biological chemistry》2002,277(23):20763-20773
The functions of the two proteins defective in autosomal dominant polycystic kidney disease, polycystin-1 and polycystin-2, have not been fully clarified, but it has been hypothesized that they may heterodimerize to form a "polycystin complex" involved in cell adhesion. In this paper, we demonstrate for the first time the existence of a native polycystin complex in mouse kidney tubular cells transgenic for PKD1, non-transgenic kidney cells, and normal adult human kidney. Polycystin-1 is heavily N-glycosylated, and several glycosylated forms of polycystin-1 differing in their sensitivity to endoglycosidase H (Endo H) were found; in contrast, native polycystin-2 was fully Endo H-sensitive. Using highly specific antibodies to both proteins, we show that polycystin-2 associates selectively with two species of full-length polycystin-1, one Endo H-sensitive and the other Endo H-resistant; importantly, the latter could be further enriched in plasma membrane fractions and co-immunoprecipitated with polycystin-2. Finally, a subpopulation of this complex co-localized to the lateral cell borders of PKD1 transgenic kidney cells. These results demonstrate that polycystin-1 and polycystin-2 interact in vivo to form a stable heterodimeric complex and suggest that disruption of this complex is likely to be of primary relevance to the pathogenesis of cyst formation in autosomal dominant polycystic kidney disease. 相似文献
166.
小麦秆锈抗性遗传及抗性基因研究进展 总被引:1,自引:0,他引:1
目前国际上已发现近80个小麦抗秆锈基因,其中45个抗秆锈基因已被正式定名,58个抗秆锈基因已定位在小麦特定染色体上,其中12个基因被标记。本文对小麦抗秆锈病基因抗源、抗秆锈性遗传、分子标记研究现状及存在问题加以综述,并对抗秆锈分子遗传前景进行展望。 相似文献
167.
采用水培方式研究了LaCl3对140 mmol·L-1 NO3-硝酸盐胁迫下黄瓜幼苗光合特性的影响.结果表明: 硝酸盐胁迫显著降低了黄瓜幼苗叶绿素及类胡萝卜素含量,叶片Mg2+ ATPase、Ca2+ ATPase活性也随之降低;硝酸盐胁迫7 d,黄瓜幼苗叶片光合速率的降低以气孔限制为主,叶片AQY与CE下降,胁迫12 d则以非气孔限制为主.硝酸盐胁迫下,外加LaCl3可以使黄瓜叶片保持较高的Mg2+ ATPase、Ca2+ ATPase活性及叶绿素和类胡萝卜素含量,尤其是外加低浓度(20 μmol·L-1)LaCl3显著增加了叶片类胡萝卜素含量;LaCl3还具有降低气孔关闭、改善叶片气体交换功能,减缓叶片Fv/Fm、ФPSII、AQY、CE及qP的降低幅度等作用,使叶片在盐胁迫下保持较高的光能利用率及CO2同化能力.20 μmol·L-1 LaCl3可以有效缓解硝酸盐对黄瓜幼苗光合作用的影响,而200 μmol·L-1LaCl3在胁迫初期对黄瓜幼苗有缓解效果,后期则效果不明显.该结果可为设施土壤的改良提供新的途径. 相似文献
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Zhang W Yue B Wang X Zhang X Xie Z Liu N Fu W Yuan Y Chen D Fu D Zhao B Yin Y Yan X Wang X Zhang R Liu J Li M Tang Y Hou R Zhang Z 《Molecular biology reports》2011,38(7):4257-4264
In order to investigate the mitochondrial genome of Panthera tigris amoyensis, two South China tigers (P25 and P27) were analyzed following 15 cymt-specific primer sets. The entire mtDNA sequence was found to be 16,957 bp and 17,001 bp long for P25 and P27 respectively, and this difference in length between P25 and P27 occurred in the number of tandem repeats in the RS-3 segment of the control region. The structural characteristics of complete P. t. amoyensis mitochondrial genomes were also highly similar to those of P. uncia. Additionally, the rate of point mutation was only 0.3% and a total of 59 variable sites between P25 and P27 were found. Out of the 59 variable sites, 6 were located in 6 different tRNA genes, 6 in the 2 rRNA genes, 7 in non-coding regions (one located between tRNA-Asn and tRNA-Tyr and six in the D-loop), and 40 in 10 protein-coding genes. COI held the largest amount of variable sites (9 sites) and Cytb contained the highest variable rate (0.7%) in the complete sequences. Moreover, out of the 40 variable sites located in 10 protein-coding genes, 12 sites were nonsynonymous. 相似文献
170.
An isoform of GTPase regulator DOCK4 localizes to the stereocilia in the inner ear and binds to harmonin (USH1C) 总被引:2,自引:0,他引:2
Yan D Li F Hall ML Sage C Hu WH Giallourakis C Upadhyay G Ouyang XM Du LL Bethea JR Chen ZY Yajnik V Liu XZ 《Journal of molecular biology》2006,357(3):755-764
The driving forces for the regulation of cell morphology are the Rho family GTPases that coordinate the assembly of the actin cytoskeleton. This dynamic feature is a result of tight coupling between the cytoskeleton and signal transduction and is facilitated by actin-binding proteins (ABPs). Mutations in the actin bundling and PDZ domain-containing protein harmonin are the causes of Usher syndrome type 1C (USH1C), a syndrome of congenital deafness and progressive blindness, as well as certain forms of non-syndromic deafness. Here, we have used the yeast two-hybrid assay to isolate molecular partners of harmonin and identified DOCK4, an unconventional guanine exchange factor for the Rho family of guanosine triphosphatases (Rho GEF GTPases), as a protein interacting with harmonin. Detailed molecular analysis revealed that a novel DOCK4 isoform (DOCK4-Ex49) is expressed in the brain, eye and inner ear tissues. We have further provided evidence that the DOCK4-Ex49 binds to nucleotide free Rac as effectively as DOCK2 and DOCK4 and it is a potent Rac activator. By immunostaining using a peptide antibody specific to DOCK4-Ex49, we showed its localization in the inner ear within the hair bundles along the stereocilia (SC). Together, our data indicate a possible Rac-DOCK4-ABP harmonin-activated signaling pathway in regulating actin cytoskeleton organization in stereocilia. 相似文献