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91.
Biology Bulletin - CRISPR is an adaptive immune defense system found in bacteria and archaea that is resistant to heterologous invasive genetic material. Later studies showed that the CRISPR system... 相似文献
92.
Pan Y Chu T Dong S Hao Y Ren X Wang J Wang W Li C Zhang Z Zhou Y 《Molecular biology reports》2012,39(9):8581-8594
The study was designed to investigate feasibility of tissue culture in vitro utilizing static culture method. Annulus fibrosus cells obtained from spine of rabbits were cultured. Results showed that fibrous tissue infiltration could be detected in shallow layer. With extended time, tissue infiltration depth increased, but there were still a large amount of holes in central part. Fibrous tissue infiltration was detected in the control side products and inner infiltration wasn't obvious. Hydroxyproline content of the control side products gradually increased with extended culture time. Hydroxyproline content of the control side products in the third and fourth month was significantly higher than that in the first month, but lower than those of the experimental side products and normal annulus fibrosus cells. DNA content of the control side products in the third and fourth month was significantly increased compared to the first month. DNA content of the control side products at each phase point was significantly lower than that of the experimental side and normal annulus fibrosus cells. Furthermore, there was lower expression levels of the type I, II collagen mRNA and protein in the experimental side scaffolds compared to the control side product. This study demonstrates the successful formation of Intervertebral disc Anulus Fibrosus in vitro by static culture method. 相似文献
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94.
不同类型人工湿地微生物群落的研究进展 总被引:4,自引:0,他引:4
微生物是人工湿地不可缺少的成员,对湿地生态系统中物质转化、能量流动起着重要作用.本文从人工湿地微生物群落的研究方法、微生物群落结构与组成、微生物群落调节作用与环境因素的关系等方面,综述了人工湿地微生物的研究进展.各种新颖的分子生物学方法已经成为研究人工湿地的微生物多样性的有力工具,其中最常见的是变性梯度凝胶电泳(DGGE)和寡核苷酸荧光探针原位杂交(FISH);人工湿地微生物群落的调节作用主要取决于湿地的水文条件、废水的特点(包括组成成分,污染物的特点和利用性)、湿地的过滤材料或土壤类型、植物和各种环境因素;不同人工湿地类型的微生物群落组成,从多到少依次是变形菌、噬纤维菌.黄杆菌菌群、放线菌和厚壁菌.如何进一步加深对氮循环相关微生物多样性的研究,提高废水中氮的去除效率依然是未来人工湿地技术需要解决的重要问题之一. 相似文献
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96.
Toward Long‐Term Stable and Highly Efficient Perovskite Solar Cells via Effective Charge Transporting Materials 下载免费PDF全文
Perovskite solar cells (PSCs) have advanced quickly with their power conversion efficiency approaching the record of silicon solar cells. However, there is still a big challenge to obtain both high efficiency and long‐term stability for future commercialization of PSCs. The major instability issue is associated with the decomposition or phase transition of perovskite materials that are believed to be intrinsically unstable under outdoor working conditions. Herein, the authors review the approaches that marked important progress in developing new functional electron/hole transporting materials that enabled highly efficient and stable PSCs. The findings that accelerate charge diffusion and that suppress the irrevocable loss of ions diffusing out of perovskite materials and other diffusion processes are highlighted. In addition, derivative interface engineering methods to control the diffusion process of charges/ions/molecules are also reviewed. Finally, the authors propose key research issues in charge transporting materials and interface engineering with regard to the important diffusion processes that will be one of the keys to realize highly efficient and long‐term stable PSCs. 相似文献
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98.
Bo Wang Deliang Shen Junnan Tang Jing Li Yue Xiao Xiuying Chen Chang Cao Dongjian Han Erhe Gao Wen Zhao Jinying Zhang Junbiao Chang 《Journal of cellular and molecular medicine》2019,23(9):6048-6059
Sodium (±)‐5‐bromo‐2‐(a‐hydroxypentyl) benzoate (generic name: brozopine, BZP) has been reported to protect against stroke‐induced brain injury and was approved for Phase II clinical trials for treatment of stroke‐related brain damage by the China Food and Drug Administration (CFDA). However, the role of BZP in cardiac diseases, especially in pressure overload‐induced cardiac hypertrophy and heart failure, remains to be investigated. In the present study, angiotensin II stimulation and transverse aortic constriction were employed to induce cardiomyocyte hypertrophy in vitro and in vivo, respectively, prior to the assessment of myocardial cell autophagy. We observed that BZP administration ameliorated cardiomyocyte hypertrophy and excessive autophagic activity. Further results indicated that AMP‐activated protein kinase (AMPK)‐mediated activation of the mammalian target of rapamycin (mTOR) pathway likely played a role in regulation of autophagy by BZP after Ang II stimulation. The activation of AMPK with metformin reversed the BZP‐induced suppression of autophagy. Finally, for the first time, we demonstrated that BZP could protect the heart from pressure overload‐induced hypertrophy and dysfunction, and this effect is associated with its inhibition of maladaptive cardiomyocyte autophagy through the AMPK‐mTOR signalling pathway. These findings indicated that BZP may serve as a promising compound for treatment of pressure overload‐induced cardiac remodelling and heart failure. 相似文献
99.
Chen Zhi-xian Li Shu-jun Yue Jian-xiong Jiao Gai-li Liu Shao-xiang She Jian-ming Wu Jing-yin Wang Hai-bo 《植物学报(英文版)》1989,31(12)
Protoplasts were isolated from an embryogenic suspension culture of commercial cotton cv. The protoplasts were released enzymatically and isolated by centrifugation on a sucrose cushion. The isolated protoplasts were initially cultured in a liquid medium with K3 mineral salts and modified Km8p organic compositions, supplemented with 0.05–0.1 mg/l 2,4-D, 0.2–0.5 mg/l 2ip in the dark. The regenerated plantlets from protoplasts of coker312 and coker 201 cv. were obtained. Embryogenesis from protoplast of Jin4 cv. and microcolonies form protoplasts of JiHe321 and Lul cv. were observed. 相似文献
100.
A complete and high‐quality genome reference sequence of an organism provides a solid foundation for a wide research community and determines the outcomes of relevant genomic, genetic, molecular and evolutionary research. Rice is an important food crop and a model plant for grasses, and therefore was the first chosen crop plant for whole genome sequencing. The genome of the japonica representative rice variety, Nipponbare, was sequenced using a gold standard, map‐based clone‐by‐clone strategy. However, although the Nipponbare reference sequence (RefSeq) has the best quality for existing crop genome sequences, it still contains many assembly errors and gaps. To improve the Nipponbare RefSeq, first a robust method is required to detect the hidden assembly errors. Through alignments between BAC‐end sequences (BESs) embedded in the Nipponbare bacterial artificial chromosome (BAC) physical map and the Nipponbare RefSeq, we detected locations on the Nipponbare RefSeq that were inversely matched with BESs and could therefore be candidates for spurious inversions of assembly. We performed further analysis of five potential locations and confirmed assembly errors at those locations; four of them, two on chr4 and two on chr11 of the Nipponbare RefSeq (IRGSP build 5), were found to be caused by reverse repetitive sequences flanking the locations. Our approach is effective in detecting spurious inversions in the Nipponbare RefSeq and can be applied for improving the sequence qualities of other genomes as well. 相似文献