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991.
Lowe DB Bifulco N Bullock WH Claus T Coish P Dai M Dela Cruz FE Dickson D Fan D Hoover-Litty H Li T Ma X Mannelly G Monahan MK Muegge I O'Connor S Rodriguez M Shelekhin T Stolle A Sweet L Wang M Wang Y Zhang C Zhang HJ Zhang M Zhao K Zhao Q Zhu J Zhu L Tsutsumi M 《Bioorganic & medicinal chemistry letters》2006,16(2):297-301
A series of oxazole-substituted indanylacetic acids were prepared which show a spectrum of activity as ligands for PPAR nuclear receptor subtypes. 相似文献
992.
Aluminum (Al) toxicity is considered as one of the primary causes of low-rice productivity in acid soils. In the present study, quantitative trait loci (QTLs) controlling Al resistance based on relative root elongation (RRE) were dissected using a complete linkage map and a recombinant inbred lines (RILs) derived from a cross of Al-tolerant japonica cultivar Asominori (Oryza sativa L.) and Al-sensitive indica cultivar IR24 (O. sativa L.). A total of three QTLs (qRRE-1, qRRE-9, and qRRE-11) were detected on chromosomes 1, 9, and 11 with LOD score ranging from 2.64 to 3.60 and the phenotypic variance explained from 13.5 to 17.7%. The Asominori alleles were all associated with Al resistance at all the three QTLs. The existence of these QTLs was confirmed using Asominori chromosome segment substitution lines (CSSLs) in IR24 genetic background (IAS). By QTL comparative analysis, the two QTLs (qRRE-1and qRRE-9) on chromosomes 1 and 9 appeared to be consistent among different rice populations while qRRE-11 was newly detected and syntenic with a major Al resistance gene on chromosome 10 of maize. This region may provide an important case for isolating genes responsible for different mechanisms of Al resistance among different cereals. These results also provide the possibilities of enhancing Al resistance in rice breeding program by marker-assisted selection (MAS) and pyramiding QTLs. 相似文献
993.
Regulatory factors other than erythropoietin (Epo) dependence, that control mammalian erythroid terminal differentiation, are currently uncertain. Here we report the existence of erythroid differentiation factors in erythroid cytoplasm. Purification of these factors from cultured Friend virus anaemia (FVA)-infected mouse splenic erythroblasts was carried out using isoelectrophoresis and high performance of liquid chromatography techniques. We have identified intracellular erythroid differentiation denucleation factors (EDDFs) that were able to mediate the events of post-Epo-dependent erythroblast terminal differentiation. Purified EDDF proteins bound specifically to the enhancer HS2 sequence of the globin gene activated the expression of haemoglobin in mouse erythroleukaemia and K562 erythroleukaemic cells and promoted them to differentiate into mature erythrocytes. EDDF proteins began to emerge at the pro-early erythroblast stages upon exposure to Epo in culture, and increased dramatically in early erythroblast stage. The dynamic of EDDF expression and its action on the key events of erythroblast differentiation and denucleation appeared to be closely consistent with its spatiotemporal distribution. These results suggest that EDDFs are the critical intracellular regulatory factors that may act as the successive regulators to Epo, responsible for the final stages of erythroid terminal differentiation. 相似文献
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997.
The complete mitochondrial genome is of great importance for better understanding the genome-level characteristics and phylogenetic relationships among related species. In the present study, we determined the complete mitochondrial genome DNA sequence of the mud crab (Scylla paramamosain) by 454 deep sequencing and Sanger sequencing approaches. The complete genome DNA was 15,824 bp in length and contained a typical set of 13 protein-coding genes, 22 transfer RNA (tRNA) genes, two ribosomal RNA (rRNA) genes and a putative control region (CR). Of 37 genes, twenty-three were encoded by the heavy strand (H-strand), while the other ones were encoded by light strand (L-strand). The gene order in the mitochondrial genome was largely identical to those obtained in most arthropods, although the relative position of gene tRNAHis differed from other arthropods. Among 13 protein-coding genes, three (ATPase subunit 6 (ATP6), NADH dehydrogenase subunits 1 (ND1) and ND3) started with a rare start codon ATT, whereas, one gene cytochrome c oxidase subunit I (COI) ended with the incomplete stop codon TA. All 22 tRNAs could fold into a typical clover-leaf secondary structure, with the gene sizes ranging from 63 to 73 bp. The phylogenetic analysis based on 12 concatenated protein-coding genes showed that the molecular genetic relationship of 19 species of 11 genera was identical to the traditional taxonomy. 相似文献
998.
Flood control engineering system risk assessment entails fuzziness. An assessment model is developed, based on the improved fuzzy comprehensive assessment method that developed a new index (Sfin ) to judge the assessment class. The model is used to assess the flood control engineering risk of a case in China. The results show that the proposed model in the present article can rationally determine the risk status of a flood control engineering system, and has higher resolution compared to the two conventional methods, fuzzy comprehensive assessment and matter-element model method. The proposed model is flexible and adaptable for determining flood control engineering system risk status. 相似文献
999.
Xue Wang Fengting Xu Jiasen Liu Bingquan Gao Yanxin Liu Yujia Zhai Jun Ma Kai Zhang Timothy S. Baker Klaus Schulten Dong Zheng Hai Pang Fei Sun 《PLoS pathogens》2013,9(1)
Rabbit hemorrhagic disease, first described in China in 1984, causes hemorrhagic necrosis of the liver. Its etiological agent, rabbit hemorrhagic disease virus (RHDV), belongs to the Lagovirus genus in the family Caliciviridae. The detailed molecular structure of any lagovirus capsid has yet to be determined. Here, we report a cryo-electron microscopic (cryoEM) reconstruction of wild-type RHDV at 6.5 Å resolution and the crystal structures of the shell (S) and protruding (P) domains of its major capsid protein, VP60, each at 2.0 Å resolution. From these data we built a complete atomic model of the RHDV capsid. VP60 has a conserved S domain and a specific P2 sub-domain that differs from those found in other caliciviruses. As seen in the shell portion of the RHDV cryoEM map, which was resolved to ∼5.5 Å, the N-terminal arm domain of VP60 folds back onto its cognate S domain. Sequence alignments of VP60 from six groups of RHDV isolates revealed seven regions of high variation that could be mapped onto the surface of the P2 sub-domain and suggested three putative pockets might be responsible for binding to histo-blood group antigens. A flexible loop in one of these regions was shown to interact with rabbit tissue cells and contains an important epitope for anti-RHDV antibody production. Our study provides a reliable, pseudo-atomic model of a Lagovirus and suggests a new candidate for an efficient vaccine that can be used to protect rabbits from RHDV infection. 相似文献
1000.
Man-Li Liu Huan Wang Zong-Ren Wang Yu-Fen Zhang Yan-Qiu Chen Fang-Hong Zhu Yuan-Qiang Zhang Jing Ma Zhen Li 《PloS one》2013,8(3)