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We isolated a Zea mays cDNA encoding the 40S subunit cytoplasmic ribosomal protein S11. The nucleotide sequence was determined and the derived amino acid sequence compared to the corresponding Arabidopsis thaliana protein showing an homology of 90%. This ribosomal protein is encoded by a small multigene family of at least two members. The mRNA steady-state level is about one order of magnitude higher in rapidly growing parts of the plant such as the roots and shoots of seedlings compared to fully expanded leaf tissue. 相似文献
34.
CHRISTOPHE GONINDARD CATHERINE GOIGOUX ETIENNE HOLLANDE LUCIEN DUSSOURD D'HINTERLAND 《Pigment cell & melanoma research》1996,9(3):148-153
The injection of α-MSH or of one of its analogues ([Nle4-D.Phe7] α-MSH4–10) reduced, in vivo, the release of two cytokines (IL-1α and TNFα) involved in inflammation. The inflammatory state was induced in BALB/c mice by intraperitoneal injection of a sublethal dose of lipopolysaccharides (LPS). The assay of these cytokines by ELISA showed a reduction of 20% with α-MSH and between 30 and 60% with the α-MSH analogue. The α-MSH or the analogue was administered in one of two ways: intravenously or subcutaneously. The most efficient method seemed to be the subcutaneous one because it improved the activity 10,000 times more than the intravenous method. Moreover, the analogue induced a regression of mortality in the animals treated by the intravenous method. Our results show that α-MSH and one of its analogues inhibit IL-1α and TNFα, and can be used as anti-inflammatory molecules. 相似文献
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36.
The role of duplication in the expression of a variable surface glycoprotein gene of Trypanosoma brucei 总被引:1,自引:0,他引:1
The variable surface glycoprotein (VSG) genes of Trypanosoma brucei have been classified into two groups depending upon whether or not duplication of the genes is observed when they are expressed. We report here the observation of duplication apparently linked to expression of the ILTaT 1.3 gene in the ETaR 1 trypanosome stock. In the ILTaR 1 stock, expression of the ILTaT 1.3 VSG did not involve a new duplication, but instead activation of a preexisting gene copy that had been apparently generated earlier by a duplication event analogous to that directly observed in the ETaR 1 trypanosomes. The results suggest that the well-characterised gene duplications found with other VSG genes are common to all VSG genes but are not directly responsible for controlling expression. All currently available data can be accommodated by a model that assumes that gene duplication and replacement occurs independently of antigenic switching. 相似文献
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38.
The literature pertaining to the use of registered antibacterial agents in Mediterranean finfish farming is reviewed, with
an emphasis on the Greek fish-farming industry. This review provides a scientific resource dedicated to the design of future
antibacterial dosing regimes in Mediterranean fish farming, where insufficient supporting information is currently available.
This paper addresses the paucity in knowledge concerning pharmacokinetics and the efficacy and environmental impact of commonly
used antibacterials needed to direct future research and promote good practices in the euryhaline fish farming industry. Several
registered antibacterials are currently available for combating bacterial infections, including tetracyclines, (fluoro) quinolones,
potentiated sulfa, penicillin and chloramphenicol derivatives. Based on the available data, oxytetracycline (OTC) and quinolone
drugs (oxolinic acid – OA and flumequine – FLU) are the most widely used in Mediterranean aquaculture. As a result these drugs
have received the most extensive studies, whereas, there is considerable paucity of reliable data on pharmacokinetic and the
depletion characteristics of other drugs used, particularly potentiated sulfa, penicillin derivatives and florfenicol. We
find there is incomplete data on drug efficacy and minimum inhibitory concentrations (MIC) for common antibacterials used
against the major bacterial pathogens of Mediterranean fish species. Furthermore, a considerable lack of data on environmental
drug concentrations around Mediterranean fish farms was also identified, highlighting the need for more extensive environmental
studies to monitor contamination in environmental components i.e., water and sediment, and in non-target species (flora and
fauna). Prudent selection and use of antibacterials can encourage lower dosage applications, enhance treatment efficacy, and
help to minimize contamination of the environment. Selection of readily bioavailable drugs which have low environmental persistence,
low aquatic toxicity and high antibacterial efficacy is advised, to reduce potential losses to the environment and associated
toxic effects on target species and the development of bacterial resistance. Lack of present data made it impossible to provide
thorough and accurate guidance on selection and use of antibacterials and approaches for minimizing environmental impacts
for the treatment of major euryhaline aquaculture species. 相似文献
39.
Shiro Tabata Takeshi Ide Yasuyoshi Umemura Kenzo Torri 《Biochimica et Biophysica Acta (BBA)/General Subjects》1984,797(2):231-238
α-Glucosidases or maltases (EC 3.2.1.20) were purified to electrophoretic homogeneity from a respective strain of Sacchromyces cerevisiae which carries a single MAL gene, either MALα, MALβ or MALγ, using gluconate-Sepharose affinity chromography and isoelectrofocusing. Of these maltases, two types of maltase were obtained from the MALγ strain, the pI values of which were 5.6 and 5.9. From the MALα and MALβ strain was obtained only one type of maltase with the pI at 5.6 which was identical to one of the maltases from the MALγ strain. These four maltases possessed the same properties, except for pI. They were monomers with molecular weights of between 66 000 and 67 000. With regard to the substrate specificity, they hydrolyzed maltose and sucrose exclusively but not α-methulglucoside nor maltooligosaccharide. They did not differ in immunological properties. 相似文献
40.
《Current biology : CB》2020,30(22):4441-4453.e4
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