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Various process alternatives and designs of using a filter containing cellular adsorbents to remove trace viral contaminants from blood and other protein solutions have been studied. Sterilization charts have been developed that can be used to estimate the filter size required to achieve a desired sterilization criterion. A parametric study was carried out to identify various process parameters that may affect this physical trace removal process. It has been demonstrated that the adsorption rate constant is a critical parameter in the design of an efficient cellular filter for viral contaminant removal. This constant is characteristic of the virus-cell system under consideration and is shown to be particularly sensitive to the cell surface receptor density, adsorbent diameter, and fluid flow rate. Higher log titer reduction in virus concentrations can be achieved with low flow rates and no recycle. Preliminary analyses indicate the feasibility of using a magnetically stabilized fluidized filter (MSFF) reactor design for effective virus removal from these complex solutions. 相似文献
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Yu Zheng-Chao Lin Wei Zheng Xiao-Ting Chow Wah Soon Luo Yan-Na Cai Min-Ling Peng Chang-Lian 《Photosynthesis research》2021,149(1-2):41-55
Photosynthesis Research - Increasing amounts of experimental evidence show that anthocyanins provide physiological protection to plants under stress. However, the difference in photoprotection... 相似文献
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L.C. Chiang H.Y. Hsiao M.C. Flickinger L.F. Chen G.T. Tsao 《Enzyme and microbial technology》1982,4(2):93-95
The capabilities of immobilized Fusarium oxysporum f. sp. lini, Mucor sp., and Saccharomyces cerevisiae in fermenting pentose to ethanol have been compared. S. cerevisiae was found to have the best fermentation rate on d-xylulose of 0.3 g l?1 h?1. By using a separate isomerase column for converting d-xylose to d-xylulose and a yeast column for converting d-xylulose to ethanol, an ethanol concentration of 32 g l?1 was obtained from 10% d-xylose. The ethanol yield was calculated to be 64% of the theoretical yield. 相似文献
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We observed the preservation of microRNAs in unrefrigerated dried serum blots. Preservation was not adversely affected by drying or storing at 37, 45, or 60 °C instead of room temperature, but it was harmed when blots were dried incompletely before storage. Preservation of microRNAs in serum was not diminished if, instead of being kept frozen at −80 °C, it was stored as dried blots at room temperature for 5 months or at 37 °C for 4 weeks. Thus, dried blots can be a convenient and safer way to save, transport, and store serum for microRNA assays. 相似文献
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Marcio Voloch Michael R. Ladisch Victor W. Rodwell George T. Tsao 《Biotechnology and bioengineering》1981,23(6):1289-1296
Fermentation of xylose by Klebsiella pneumoniae (ATCC 8724) producers meso and nonmeso 2,3-butaneodiol. The enzyme Kinetic of 2,3-butanediol stereoisomer formation from acetone is currently under study in our laboratory. Modeling of these kinetics requires resolution of meso and racemic 2,3-butanediol and positive identification of these resolved components. We report their resolution by aqueous liquid chromatography on both an analytical and a preparative scale. The resolved stereoisomer were identified by a combination of gas chromatography, gas chromatography/mass spectroscopy, 13C-NMR spectroscopy, optical activity, and, melting points of the m-dinitrobenzoyl eaters of meso and racemic 2,3-butanediol. An aqueous liquid chromatographic technique for resolving and qualifying major components of a butanediol fermentation mixture in 40 min is presented. 相似文献
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NGF and other growth factors induce an association between ERK1 and the NGF receptor, gp140prototrk.
As detected by coimmunoprecipitation from PC12 cells, NGF induces rapid association between ERK1 (a growth factor-activated serine/threonine protein kinase) and gp140prototrk NGF receptors. In contrast, no such association is found with the closely related ERK2. Anti-trk immunocomplexes generated from NGF-treated cells also contain protein kinase activity that shares many properties with soluble ERK1. The association of both ERK1 protein and ERK-like kinase activity with gp140prototrk is maximal by 5 min of NGF treatment, persists for approximately 1 hr, and subsequently declines by 18 hr. Treatment with either basic fibroblast growth factor, epidermal growth factor, or orthovanadate also leads to association of ERK1 with gp140prototrk without tyrosine phosphorylation of the latter. The interaction between ERK1 and gp140prototrk may prove relevant to the NGF mechanism. 相似文献
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Clostridium thermocellum SS8 produced both carboxymethylcellulase (CMCase) and Avicelase when grown on cellulose. CMCase activity was unaffected by Ca2+, Mg2+, dithionate or dithiothreitol (DTT). Avicelase activity increased 2-fold with 5 mM DTT and 10 mM Ca2+. Cellulase and amylase were produced when a celluloseadapted culture was grown on starch. The mould grew best on sucrose and was inhibited by NaCl above 10 g/l. 相似文献