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Yunqing Gu Jun Cao Xinyu Zhang Hai Gao Yuyan Wang Jia Wang Juan He Xiaoyi Jiang Jinlan Zhang Guanghui Shen Jie Yang Xichen Zheng Gaowei Hu Yuanfei Zhu Shujuan Du Yunkai Zhu Rong Zhang Jianqing Xu Fei Lan Di Qu Guoliang Xu Yun Zhao Dong Gao Youhua Xie Min Luo Zhigang Lu 《Cell research》2022,32(1):24-37
Host cellular receptors play key roles in the determination of virus tropism and pathogenesis.However,little is known about SARS-CoV-2 host receptors with the e... 相似文献
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酵母RNA聚合酶ⅡRpb2和Rpb3两亚基间相互作用位点的定位 总被引:2,自引:0,他引:2
为研究S .pombeRNApolⅡ各亚基间体内装配成复合体的机制 ,本文首次用酵母双杂交系统鉴定了Rpb2和Rpb3两亚基间体内相互作用的位点。首先将Rpb2的 4个片段克隆至Gal4BD表达载体pAS2上 ,构建BD Rpb2片段融合蛋白重组质粒 ;同时将Rpb3克隆至Gal4AD表达载体pGADGH上 ,构建AD Rpb3融合蛋白重组质粒。其次 ,将pGADGHRpb3分别与pAS2Rpb2各片段重组质粒共转化到受体酵母菌Y1 90感受态细胞内 ,筛选并鉴定β gal活性阳性 (β gal+)的共转化子。最后 ,将β gal+共转化子中的Rpb2片段进行序列分析并进行同源序列比较确定其在Rpb2中的位置。结果表明 ,Rpb2与Rpb3相互作用的位点位于Rpb2的 90 2~ 989aa肽段内 相似文献
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Chen Ling Zunpeng Liu Moshi Song Weiqi Zhang Si Wang Xiaoqian Liu Shuai Ma Shuhui Sun Lina Fu Qun Chu Juan Carlos Izpisua Belmonte Zhaoxia Wang Jing Qu Yun Yuan Guang-Hui Liu 《蛋白质与细胞》2019,10(4):249-271
Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy(CADASIL)is a rare hereditary cerebrovascular disease caused by a NOTCH3 mutation.However,the underlying cellular and molecular mechanisms remain unidentified.Here,we generated non-integrative induced pluripotent stem cells(iPSCs)from fibroblasts of a CADASIL patient harboring a heterozygous NOTCH3 mutation(c.3226C>T,p.R1076C).Vascular smooth muscle cells(VSMCs)differentiated from CADASIL-specific iPSCs showed gene expression changes associated with disease phenotypes,including activation of the NOTCH and NF-kB signaling pathway,cytoskeleton disorganization,and excessive cell proliferation.In comparison,these abnormalities were not observed in vascular endothelial cells(VECs)derived from the patients iPSCs.Importantly,the abnormal upregulation of NF-kB target genes in CADASIL VSMCs was diminished by a NOTCH pathway inhibitor,providing a potential therapeutic strategy for CADASIL.Overall,using this iPSCbased disease model,our study identified clues for studying the pathogenic mechanisms of CADASIL and developing treatment strategies for this disease. 相似文献
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LuJiang Qu Wei Liu FangXi Yang ZhuoCheng Hou JiangXia Zheng GuiYun Xu Ning Yang 《中国科学:生命科学英文版》2009,52(11):1030-1035
In order to elucidate the domestication history of Peking ducks, 190 blood samples from six Chinese indigenous duck breeds were collected with186 individualsgenotyped by 15 microsatellite markers. Both the FST and Nei’s standard genetic distances (Ds) from the microsatellite data indicated high genetic differentiation between Peking duck and other Chinese indigenous breeds. The haplotype network with mtDNA data showed that most of the Peking duck haplotypes were distinctly different from those of other domestic breeds. Although the H01 haplotype was shared by all domesticated duck breeds, Peking ducks displayed 12 specific domestic duck haplotypes, including four similar haplotypes H02, H04, H08 and H22, that formed a single haplogroup (A). Both H02 and H22 haplotypes were also shared by mallard and Peking ducks, indicating that Peking ducks originated from wild mallard ducks. 相似文献
48.
Human plasma phospholipid transfer protein (PLTP) contains six potential N-glycosylation sites (Asn-X-Ser). To study the role
of these sites on PLTP structure and function, seven variants in which asparagine (N) residues were converted to glycine (G)
were prepared by site-directed mutagenesis. These were N47G, N77G, N100G, N126G, N228G, N381G and N47, 77, 100, 126, 228, 381G (NnullG). These variants and wild-type (WT) PLTP were expressed in COS-7 cells. Intracellular and secreted PLTP mass was analyzed
by Western blots and quantitative enzyme-linked immunosorbent assay; PLTP activities in cellular lysates and media were based
on the transfer of [3H]dipalmitoylphosphatidylcholine from phospholipid single bilayer vesicles to HDL. NnullG was not detected intracellularly. N381G was similar to WT PLTP with respect to specific activity and secretion efficiency. The specific activities of N47G, N77G, N100G, N126G, N228G and N381G were similar in cell lysate (range = 67–90% WT) and medium (range = 65–77% WT). Intracellular masses of these PLTP variants
were similar to that of WT (Mean = 103% WT); mean secreted mass was 88% WT. These results suggest that secretion-competent
PLTP requires glycosylation but that no single glycosylation site is required. 相似文献
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Mingshan Xue Yifeng Zeng Runpei Lin Hui-Qi Qu Teng Zhang Xiaohua Douglas Zhang Yueting Liang Yingjie Zhen Hao Chen Zhifeng Huang Haisheng Hu Peiyan Zheng Hakon Hakonarson Luqian Zhou Baoqing Sun 《Experimental biology and medicine (Maywood, N.J.)》2021,246(14):1586
While there is no cure for chronic obstructive pulmonary disease (COPD), its progressive nature and the formidable challenge to manage its symptoms warrant a more extensive study of the pathogenesis and related mechanisms. A new emphasis on COPD study is the change of energy metabolism. For the first time, this study investigated the anaerobic and aerobic energy metabolic pathways in COPD using the metabolomic approach. Metabolomic analysis was used to investigate energy metabolites in 140 COPD patients. The significance of energy metabolism in COPD was comprehensively explored by the Global Initiative for Chronic Obstructive Lung Disease–GOLD grading, acute exacerbation vs. stable phase (either clinical stability or four-week stable phase), age group, smoking index, lung function, and COPD Assessment Test (CAT) score. Through comprehensive evaluation, we found that COPD patients have a significant imbalance in the aerobic and anaerobic energy metabolisms in resting state, and a high tendency of anaerobic energy supply mechanism that correlates positively with disease progression. This study highlighted the significance of anaerobic and low-efficiency energy supply pathways in lung injury and linked it to the energy-inflammation-lung ventilatory function and the motion limitation mechanism in COPD patients, which implies a novel therapeutic direction for this devastating disease. 相似文献