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71.
Modification with homocysteine (Hcy)-thiolactone leads to the formation of N-Hcy-Lys-protein. Although N-Hcy-Lys-proteins are immunogenic, pure antibodies have not yet been obtained. Here we describe synthesis and application of Nomega-homocysteinyl-aminohexyl-Agarose for affinity purification of anti-N-Hcy-Lys-protein antibodies. Nomega-homocysteinyl-aminohexyl-Agarose was prepared by N-homocysteinylation of omega-aminohexyl-Agarose with Hcy-thiolactone. Immune serum was obtained from rabbits inoculated with N-Hcy-Lys-keyhole limpet hemocyanine and IgG fraction prepared by chromatography on protein A-Agarose. Anti-N-Hcy-Lys-protein IgG was adsorbed on Nomega-homocysteinyl-aminohexyl-Agarose column at pH 8.6 and eluted with a pH 2.3 buffer. Enzyme-linked immunosorbent assays demonstrate that the antibody recognizes specifically N-homocysteinylated variants of hemoglobin, albumin, transferrin, and antitrypsin.  相似文献   
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Information on spatial and temporal patterns of genetic diversity is a prerequisite to understanding the demography of populations, and is fundamental to successful management and conservation of species. In the sea, it has been observed that oceanographic and other physical forces can constitute barriers to gene flow that may result in similar population genetic structures in different species. Such similarities among species would greatly simplify management of genetic biodiversity. Here, we tested for shared genetic patterns in a complex marine area, the Baltic Sea. We assessed spatial patterns of intraspecific genetic diversity and differentiation in seven ecologically important species of the Baltic ecosystem—Atlantic herring (Clupea harengus), northern pike (Esox lucius), European whitefish (Coregonus lavaretus), three-spined stickleback (Gasterosteus aculeatus), nine-spined stickleback (Pungitius pungitius), blue mussel (Mytilus spp.), and bladderwrack (Fucus vesiculosus). We used nuclear genetic data of putatively neutral microsatellite and SNP loci from samples collected from seven regions throughout the Baltic Sea, and reference samples from North Atlantic areas. Overall, patterns of genetic diversity and differentiation among sampling regions were unique for each species, although all six species with Atlantic samples indicated strong resistence to Atlantic-Baltic gene-flow. Major genetic barriers were not shared among species within the Baltic Sea; most species show genetic heterogeneity, but significant isolation by distance was only detected in pike and whitefish. These species-specific patterns of genetic structure preclude generalizations and emphasize the need to undertake genetic surveys for species separately, and to design management plans taking into consideration the specific structures of each species.  相似文献   
74.
N-(m-Nitrophenyl)-beta-D-glucopyranosylamine (Gln), N-(N-methylphenyl)-beta-D-glucopyranosylamine (Glm), N-beta-D-glucopyranosylpyrazole (Glp), and N-beta-D-glucopyranosylimidazole (Gli) have been synthesized. Their basicity constants, pKb, determined in methanol were, respectively, 14.99, 14.36, 15.04, and 9.74. The derivatives of secondary amines (Glm, Glp, and Gli) did not mutarotate in methanol in the presence of 3,5-dinitrobenzoic acid and hydrochloric acid. The heats of formation and entropies were calculated by the AM1 and PM3 methods for the glucosylamines and their cations under consideration of two plausible protonation centers. Thermodynamic parameters for the proton transfer in the reaction: glucosylamine + CH3OH2+ = glucosylamineH+ + CH3OH were determined and the protonation center in the glucosylamine molecule was identified. The mechanism of mutarotation of the glucosylamines is discussed and the conclusion made that formation of an acyclic immonium cation is not a satisfactory condition for the reaction to proceed.  相似文献   
75.
p24 proteins are assumed to play an important role in the transport of secreted and transmembrane proteins into membranes. However, only few cargo proteins are known that partially, but in no case completely require p24 proteins for membrane transport. Here, we show that two p24 proteins are essential for dorsoventral patterning of Drosophila melanogaster embryo. Mutations in the genes, eclair (eca) and baiser (bai), encoding two p24 proteins reduce signalling by the TGF-beta homologue, Dpp, in early embryos. This effect is strictly maternal and specific to early embryogenesis, as Dpp signalling in other contexts is not notably affected. We provide genetic evidence that in the absence of eca or bai function in the oocyte, the maternally expressed type I TGF-beta receptor Tkv is not active. We propose that during early embryogenesis eca and bai are specifically required for the activity of the maternal Tkv, while the zygotic Tkv is not affected in the mutant embryos. Mutations in either eca or bai are sufficient for the depletion of Tkv activity and no enhancement of the phenotypes was observed in embryos derived from oocytes mutant for both genes. The dependence of maternal Tkv protein on the products of p24 genes may serve as an in vivo model for studying p24 proteins.  相似文献   
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Three novel morphiceptin analogs, in which Pro in position 2 and/or 4 was replaced by cis‐4‐aminoproline connected with the preceding amino acid through the primary amino group, were synthesized. The opioid receptor affinities, functional assay results, enzymatic degradation studies and experimental and in silico structural analysis of such analogs are presented. Copyright © 2017 European Peptide Society and John Wiley & Sons, Ltd.  相似文献   
78.
Witkin 1980-1988, 42 patients (4 males and 38 females) were operated for the gall-bladder cancer; it makes 2.9% of the patients who underwent cholecystectomies. Average age of female patients was 65 and males--71 years. No typical complaints were revealed making possible an early diagnosing of the gall-bladder cancer. The far advanced stages of this cancer were found in 41 cases. In i case no macroscopic features of the cancer were found. Cancer was diagnosed by means of histopathological examination. One patient (woman) survived more than 3 years after operation; 3 women survived more than 1 year. Average survival is 4 months.  相似文献   
79.
An analysis was carried out of the microbiological investigations of clinical material samples obtained from the patients of two oncology centres belonging to the Warsaw Oncology Centre. Microorganisms cultured from urine, blood, catheters, smears of wounds and other materials were analysed. From 4839 clinical material samples from the Ursynów centre 1755 bacterial strains were isolated. From 423 samples from the centre in Wawelska Street 171 strains were obtained. In infections of patients from the centres the number of Gram-positive cocci was twice that of Gram-negative rods. In the investigated clinical material S. aureus was the most frequently isolated Gram-positive coccus, while E. coli was the most frequent species among Gram-negative bacteria. In the infections of oncological patients a considerable frequency was noted of yeast-like fungi, especially C. albicans. Particularly disquieting was the increasing number of isolates of C. glabrata and C. krusei strains resistant to fluconazole.  相似文献   
80.
Genetic analysis of Curvularia lunata IM 2901 transformants, previously obtained by electroporation with plasmid pAN7-1, was carried out. Isolates displayed several differences in hygromycin B resistance and their physiology. It was shown that plasmid pAN7-1 was integrated in different copy numbers and at different positions in the genome of the strains studied. Both the wild type and pAN7-1 isolates, when growing in liquid media, produced an extracellular emulsifying agent. The transformants differed in their growth kinetics, intensity of surfactant production and in the efficiency of cortexolone 11beta-hydroxylation, in comparison with the wild type. The micro-organisms varied in susceptibility to the lytic enzyme complex (Novozyme 234), which indicated the presence of differences in their cell wall composition and/or in architecture caused by an integrated plasmid pAN7-1.  相似文献   
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