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981.
Jia-tang Li Jing Che Robert W. Murphy Hui Zhao Er-mi Zhao Ding-qi Rao Ya-ping Zhang 《Molecular phylogenetics and evolution》2009,53(2):509-522
The phylogenetic relationships among 12 genera of treefrogs (Family, Rhacophoridae), were investigated based on a large sequence data set, including five nuclear (brain-derived neurotrophic factor, proopiomelanocortin, recombination activating gene 1, tyrosinase, rhodopsin) and three mitochondrial (partial 12S and 16S ribosomal RNA and the complete valine t-RNA) genes. Phylogenetic analysis of the nuclear gene sequences resolved three major clades. The first group included Philautus, Pseudophilautus, Kurixalus, Gracixalus, and Theloderma moloch; Pseudophilautus and Kurixalus were sister taxa. The second group consisted of Nyctixalus and Theloderma. The third group contained Feihyla, Polypedates, Rhacophorus, and Chiromantis vittatus; Polypedates and Feihyla were sister taxa. Analyses of the nuclear and mitochondrial genes supported the following results: (1) Genus Liuixalus formed the sister group of all other rhacophorines. (2) Philautus, Theloderma, and Chiromantis were not resolved as monophyletic genera. Four groups, including Philautus ocellatus and P. hainanus, P. longchuanensis and P. gryllus, P. banaensis, and P. quyeti nested well within the genera Liuixalus, Pseudophilautus, Kurixalus, and Gracixalus, respectively. (3) Theloderma moloch and Chiromantis vittatus did not cluster with other species of Theloderma and Chiromantis, respectively. Foam nesting evolved only once, as did laying eggs in a jelly-like matrix containing some bubbles. Terrestrial direct development evolved twice in the Rhacophoridae. 相似文献
982.
Rina Barouch-Bentov Jianwei Che Christian C. Lee Yating Yang Ann Herman Yong Jia Anastasia Velentza James Watson Luise Sternberg Sunjun Kim Niusha Ziaee Andrew Miller Carie Jackson Manabu Fujimoto Mike Young Serge Batalov Yi Liu Markus Warmuth Tim Wiltshire Michael P. Cooke Karsten Sauer 《Molecular cell》2009,33(1):43-52
983.
984.
Three unusual compounds that a one-dimensional (1-D) chain and two two-dimensional (2-D) sheets are synthesized by the combination of three different metallic salts and organic ligands that 10,11,12,13-tetrahydro-4,5,9,14-tetraaza-benzo[b]triphenylene (TTBT) and 1,3-benzenedicarboxylic acid (1,3-H2BDC), viz. [Cd(TTBT)(1,3-BDC)]n (1), [Mn2(TTBT)2(1,3-BDC)2]n (2) and [Zn2(TTBT)2(1,3-BDC)2]n · 2nH2O (3), characterized by elemental analyses, thermal gravimetry (TG), fluorescent emission and single crystal X-ray diffraction analyses. 1 has a square-wave-like 1-D chain structure, which further assembled into a 2-D layer through an interchain π-π interaction with approximate elliptical channels along c axis. 2 and 3 possess similar 2-D sheet structures; in particular the adjacent sheets are further interlinked by intersheet π-π stacking interaction to form three-dimensional (3-D) supramolecular network. All compounds have extended solid-state structure formed by π-π interactions, and there is an excellent opportunity to elucidate the difference in the formation of extended networks in these three compounds. Furthermore, solid-state luminescent spectra of the complexes 1 and 3 indicate intense green fluorescent emission. 相似文献
985.
Yulan Xu Chunquan Sheng Wenya Wang Xiaoying Che Yongbing Cao Guoqiang Dong Shengzheng Wang Haitao Ji Zhenyuan Miao Jianzhong Yao Wannian Zhang 《Bioorganic & medicinal chemistry letters》2010,20(9):2942-2945
In an attempt to find novel azole antifungal agents with improved activity and broader spectrum, computer modeling was used to design a series of new azoles with piperidin-4-one O-substituted oxime side chains. Molecular docking studies revealed that they formed hydrophobic and hydrogen-bonding interactions with lanosterol 14α-demethylase of Candida albicans (CACYP51). In vitro antifungal assay indicates that most of the synthesized compounds showed good activity against tested fungal pathogens. In comparison with fluconazole, itraconazole and voriconazole, several compounds (such as 10c, 10e, and 10i) show more potent antifungal activity and broader spectrum, suggesting that they are promising leads for the development of novel antifungal agents. 相似文献
986.
Chunquan Sheng Shuanghong Chen Haitao Ji Guoqiang Dong Xiaoyin Che Wenya Wang Zhenyuan Miao Jianzhong Yao Jiaguo Lü Wei Guo Wannian Zhang 《Journal of molecular modeling》2010,16(2):279-284
Lanosterol 14α-demethylase (CYP51) is an essential enzyme in the fungal life cycle and also an important target for the antifungal drug development. Based on the multiple sequence alignments of CYP51 family, an evolutionary tree of the CYP51 family was constructed by the evolutionary trace (ET) method. The identified trace residues could provide a reliable and rational guide to the design of CYP51 mutations and give more information about the detailed mechanism of substrate (drug) recognition and binding. The reliability of ET analysis to identify residues of functional importance was validated by the reported site-directed mutagenesis studies of CYP51s. Several residues in the active site were also validated by our mutagenesis studies. Mapping the identified trace residues onto the active site of the modeled structure of Candida albicans CYP51 (CACYP51) may provide useful information for the design of novel antifungal agents. 相似文献
987.
Polyhydroxyalkanoate (PHA) production using waste vegetable oil by Pseudomonas sp. strain DR2 总被引:1,自引:0,他引:1
Song JH Jeon CO Choi MH Yoon SC Park W 《Journal of microbiology and biotechnology》2008,18(8):1408-1415
To produce polyhydroxyalkanoate (PHA) from inexpensive substrates by bacteria, vegetable-oil-degrading bacteria were isolated from a rice field using enrichment cultivation. The isolated Pseudomonas sp. strain DR2 showed clear orange or red spots of accumulated PHA granules when grown on phosphate and nitrogen limited medium containing vegetable oil as the sole carbon source and stained with Nile blue A. Up to 37.34% (w/w) of intracellular PHA was produced from corn oil, which consisted of three major 3-hydroxyalkanoates; octanoic (C8:0, 37.75% of the total 3-hydroxyalkanoate content of PHA), decanoic (C10:0, 36.74%), and dodecanoic (C12:0, 11.36%). Pseudomonas sp. strain DR2 accumulated up to 23.52% (w/w) of PHAMCL from waste vegetable oil. The proportion of 3- hydroxyalkanoate of the waste vegetable-oil-derived PHA [hexanoic (5.86%), octanoic (45.67%), decanoic (34.88%), tetradecanoic (8.35%), and hexadecanoic (5.24%)] showed a composition ratio different from that of the corn-oil-derived PHA. Strain DR2 used three major fatty acids in the same ratio, and linoleic acid was the major source of PHA production. Interestingly, the production of PHA in Pseudomonas sp. strain DR2 could not occur in either acetate- or butyrate-amended media. Pseudomonas sp. strain DR2 accumulated a greater amount of PHA than other well-studied strains (Chromobacterium violaceum and Ralstonia eutropha H16) when grown on vegetable oil. The data showed that Pseudomonas sp. strain DR2 was capable of producing PHA from waste vegetable oil. 相似文献
988.
989.
990.
Mountains too high and valleys too deep drive population structuring and demographics in a Qinghai–Tibetan Plateau frog Nanorana pleskei (Dicroglossidae) 下载免费PDF全文
Weiwei Zhou Jieqiong Jin Jun Wu Hongman Chen Junxiao Yang Robert W. Murphy Jing Che 《Ecology and evolution》2017,7(1):240-252
Pleistocene glacial–interglacial climatic oscillations greatly shaped the current genetic structure of many species. However, geographic features may influence the impact of climatic cycling. Distinct geographic and environmental characters between northern and southern parts of the eastern Qinghai–Tibetan Plateau (EQTP) facilitate explorations into the impacts of geographic features on species. The northern parts of EQTP contain large areas of marsh, and the environment is rather homogeneous. In contrast, the southern EQTP harbors complex alpine valleys and a much more heterogeneous setting. We evaluate DNA sequence variation from both the mitochondrial and nuclear genomes in Nanorana pleskei, a species endemic to the EQTP. Hypothesis testing on the evolutionary history of N. pleskei indicates that northern populations can disperse freely, but alpine valleys isolate southern populations. Demographic histories between northern and southern populations also differ. Northern populations appear to have experienced population expansions, while southern frogs exhibit a far more stable demographic history. By combining climatic analyses and species' distribution models, our study suggests that geographic and environmental features drive the differences between the northern and southern EQTP. 相似文献