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881.
882.
Jignasha T. Thumar Kinjal Dhulia Satya P. Singh 《World journal of microbiology & biotechnology》2010,26(11):2081-2087
A halotolerant alkaliphilic actinomycete, Kut-8, was isolated from saline desert of Kutch, Western India. It has been identified
as Streptomyces aburaviensis based on the chemotaxonomic characteristics, including cell wall constituents. Kut-8 is Gram-positive having a spiral sporophore
with dark green and fluffy spore mass. It was able to grow with 15%, w/v NaCl with optimum being in the range of 5–10%. It
grew optimally at pH 9 with slow growth at neutral pH. The cell wall contained l-diaminopimelic acid and no diagnostic sugars. It produced an antibiotic that selectively inhibited the growth of Gram-positive
bacteria, with Bacillus subtilis being the most sensitive. Kut-8 secreted the antibiotic optimally during mid-stationary phase (on day 14 of growth in liquid
culture). The crude antibiotic metabolites were separated by various solvent systems with hexane–methanol–water giving the
best separation. The results of bioautographs revealed the presence of single active compound in the Kut-8 antibiotic filtrate.
Partial purification of antibiotic metabolite by charcoal absorption and methanol extraction resulted in enhanced antimicrobial
activity by 4.16-fold. The study holds significance as only few salt-tolerant alkaliphilic actinomycetes from saline deserts
have been explored and information on their antimicrobial potential is still scarce. 相似文献
883.
Kiyoshi Hayashi Li Ying Satya Singh Satoshi Kaneko Satoru Nirasawa Tsuyoshi Shimonishi Yasushi Kawata Taiji Imoto Motomitsu Kitaoka 《Journal of Molecular Catalysis .B, Enzymatic》2001,11(4-6):811-816
The genes of family 3 β-glucosidase enzymes consist of five distinct regions; the N-terminal residues, an N-terminal catalytic domain, a nonhomologous region, a C-terminal domain of unknown function and the C-terminal residues. The β-glucosidase genes derived from Cellvibrio gilvus (CG) and Agrobacterium tumefaciens (AT) have been subjected to gene deletion, truncation and shuffling. The folding information was found to be distributed unevenly across the different regions based on the gene manipulation results. Chimeric enzymes with improved enzyme characteristics were obtained only by gene shuffling at the C-terminal domain. 相似文献
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886.
Indole, tryptophan, tryptamine and skatole were isolated from the leaves of Tecoma stans. Anthranilic acid was also identified in its free form, in contrast to its glucoside, in Jasminum grandiflorum. The presence of both indole and anthranilic acid in the leaves of Tecoma stans indicates that they are the true substrate and product of indole oxygenase from the leaves of Tecoma stans. 相似文献
887.
John A. Greager Tzu-Chieh Chao John M. Brown Dan G. Pavel Micheal J. Blend Tapas K. Das Gupta 《Cancer immunology, immunotherapy : CII》1991,33(5):341-345
Summary A group of 16 sarcoma patients with suspected advanced disease were studied with a radiolabeled anti-sarcoma monoclonal antibody (mAb 19–24) in an attempt to localize tumor deposits. All 16 patients received125I-mAb 19–24 and then had external-probe analysis and imaging performed. Confirmation of tumor deposits was done at surgery or by autopsy. Tissues were studied in surgical patients when possible and analyzed for radioactivity, and tumor-to-blood ratios ranged from 0.6 to 36.8. In conjunction with the patients previously studied, probe results had an overall sensitivity of 83.3% and an overall specificity of 100%; scintigraphic results showed an overall sensitivity of 78.9% and an overall specificity of 100%. Radiolabeled mAb 19–24 may be developed into a useful tool for clinical immunodetection of sarcoma deposits.This study is supported by American Cancer Society (Illinois Division) grant 88-53 相似文献
888.
Mandal Atin K. Roy Koushik Sil Parames C. Yadav Satya P. Sen Parimal C. 《Molecular and cellular biochemistry》2001,223(1-2):7-14
A protein isolated from goat testis cytosol is found to inhibit Na+,K+-ATPase from rat brain microsomes. The inhibitor has been purified by ammonium sulphate precipitation followed by hydroxyapatite column chromatography. The purified fraction appears as a single polypeptide band on 10% SDS-PAGE of approximate molecular mass of 70 kDa. The concentration at which 50% inhibition (I50) occurs is in the nanomolar range. The inhibitor seems to bind Na+,K+-ATPase reversibly at ATP binding site in a competitive manner with ATP, but away from ouabain binding site. It does not affect p-nitrophenyl-phosphatase activity. The inhibitor is found to inhibit the phosphorylation step of the Na+,K+-ATPase. The enhancement of tryptophan fluorescence and changes in CD pattern suggest conformational changes of Na+,K+-ATPase on binding to the inhibitor. Amino acid sequence of the trypsinised fragments show some homology with aldehyde reductase. 相似文献
889.
Jayasha Shandilya Parijat Senapati Karthigeyan Dhanasekaran Suma S. Bangalore Manoj Kumar A. Hari Kishore Akshay Bhat Gopinath S. Kodaganur Tapas K. Kundu 《FEBS letters》2014
The functional association of NPM1 with Aurora kinases is well documented. Surprisingly, although NPM1 is a well characterized phosphoprotein, it is unknown whether it is a substrate of Aurora kinases. We have found that Aurora kinases A and B can phosphorylate NPM1 at a single serine residue, Ser125, in vitro and in vivo. Phosphorylated-S125-NPM1 (pS125-NPM1) localizes to the midbody region during late cytokinesis where it colocalizes with Aurora B. The overexpression of mutant (S125A) NPM1 resulted in the deregulation of centrosome duplication and mitotic defects possibly due to cytokinesis failure. These data suggest that Aurora kinase B-mediated phosphorylation of NPM1 plays a critical role during mitosis, which could have wider implications in oncogenesis. 相似文献
890.