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171.
172.
The activities of glutaminase, glutamine synthetase (GS), arginase and ornithine amino transferase (orn-T) were studied in three regions of rat brain in heightened neuronal activity by producing convulsions by leptazol. These enzymes were studied in preconvulsive, convulsive and postconvulsive phases. Glutaminase activity was found to increase in all the three regions in the preconvulsive and convulsive phases. GS activity decreased in the preconvulsive phase but rose gradually to the control level when the postconvulsive phase was reached. The activity of arginase decreased in the cerebellum in preconvulsive and convulsive phases. However, in the cerebral cortex there was a decrease in the activity of this enzyme only in the convulsive phase. The results suggest that glutamine acts more likely as a precursor for the neurotransmitter pool of glutamate, while ornithine serves more as a precursor for the neurotransmitter pool of GABA. 相似文献
173.
Summary We have investigated the efficacy of the cell blot assay in analysis of the secretion of hormones and peptides from rat anterior
pituitary cells. The dissociated cells are cultured on pieces of translucent polyvinylidene difluoride membrane, on which
their secretory products are adsorbed and subsequently immunostained. The area and integrated optical density of the stained
‘halo’ surrounding individual cells is measured by microscopical image processing and the values for basal secretion of a
particular hormone or peptide are compared with those after application of secretagogues or inhibitors. Our experiments tested
established responses of dissociated rat anterior pituitary cells; in general, the results were as expected. Double immunoenzymatic
staining could be used to show secretion of two products from the same or different cells in one preparation, and immunofluorescence
with fluorescein- and/or rhodamine-labelled antibodies could be used instead of enzyme-linked immunolabelling. Optimal dilutions
of immunoreagents were much higher than those used for immunocytochemistry on tissue sections. Although the cell blot assay
does not provide absolute quantification, since some of the secreted product escapes into the medium, it is a relatively easy
and economical way for morphologists to compare secretion from individual cells under varying conditions. 相似文献
174.
Christopher Hooper Swamy S Puttamadappa Zak Loring Alexander Shekhtman Joanna C Bakowska 《BMC biology》2010,8(1):72
Background
Spartin protein is involved in degradation of epidermal growth factor receptor and turnover of lipid droplets and a lack of expression of this protein is responsible for hereditary spastic paraplegia type 20 (SPG20). Spartin is a multifunctional protein that associates with many cellular organelles, including lipid droplets. Recent studies showed that spartin interacts with E3 ubiquitin ligases that belong to the neural precursor cell-expressed developmentally downregulated gene (Nedd4) family, including atrophin-1-interacting protein 4 (AIP4/ITCH). However, the biological importance of the spartin-AIP4 interaction remains unknown. 相似文献175.
176.
177.
A vitamin D analogue containing an affinity and a photoaffinity probe (affinity-driven cross-linker, Double Label) was synthesized. An unknown factor, associated with vitamin D receptor (VDR), was isolated from rat liver nuclear extract using a GST-VDR-ligand-binding domain fusion protein (GST-VDR-LBD), affinity labeled with Double Label, and protein-protein cross-linking by photolysis. 相似文献
178.
Mohamed M Thabet Thomas WJ Huizinga Désirée M van der Heijde Annette HM van der Helm-van Mil 《Arthritis research & therapy》2009,11(5):1-9
Introduction
Evidence suggests that citrullinated fibrin(ogen) may be a potential in vivo target of anticitrullinated protein/peptide antibodies (ACPA) in rheumatoid arthritis (RA). We compared the diagnostic yield of three enzyme-linked immunosorbent assay (ELISA) tests by using chimeric fibrin/filaggrin citrullinated synthetic peptides (CFFCP1, CFFCP2, CFFCP3) with a commercial CCP2-based test in RA and analyzed their prognostic values in early RA.Methods
Samples from 307 blood donors and patients with RA (322), psoriatic arthritis (133), systemic lupus erythematosus (119), and hepatitis C infection (84) were assayed by using CFFCP- and CCP2-based tests. Autoantibodies also were analyzed at baseline and during a 2-year follow-up in 98 early RA patients to determine their prognostic value.Results
With cutoffs giving 98% specificity for RA versus blood donors, the sensitivity was 72.1% for CFFCP1, 78.0% for CFFCP2, 71.4% for CFFCP3, and 73.9% for CCP2, with positive predictive values greater than 97% in all cases. CFFCP sensitivity in RA increased to 80.4% without losing specificity when positivity was considered as any positive anti-CFFCP status. Specificity of the three CFFCP tests versus other rheumatic populations was high (> 90%) and similar to those for the CCP2. In early RA, CFFCP1 best identified patients with a poor radiographic outcome. Radiographic progression was faster in the small subgroup of CCP2-negative and CFFCP1-positive patients than in those negative for both autoantibodies. CFFCP antibodies decreased after 1 year, but without any correlation with changes in disease activity.Conclusions
CFFCP-based assays are highly sensitive and specific for RA. Early RA patients with anti-CFFCP1 antibodies, including CCP2-negative patients, show greater radiographic progression. 相似文献179.
An extra layer of complexity in the regulation of gene expression in bacteria is now apparent through previously unanticipated
roles of noncoding and antisense RNAs. 相似文献
180.
M. Rambabu M. Upender D. Ujjwala T. Ugandhar M. Praveen N. Rama Swamy 《In vitro cellular & developmental biology. Plant》2006,42(5):418-421
Summary This study reports a protocol for germination of Givotia rottleriformis (var. Tel. Thella Poniki) using zygotic embryo culture. A 100% germination was obtained by culturing the embryos on Murashige
and Skoog medium containing 30 gl−1 sucrose. A sucrose concentration lower or higher than 30 gl−1 resulted in lower germination or promoted callus formation. The seedling growth was promoted by the addition of 100 mgl−1 tyrosine in the medium. Seedlings germinated in the presence of 0.2–0.4 mgl−1 α-naphthaleneacetic acid and 0.3–0.5 mgl−1 indole-3-butyric acid were abnormal, showing a slender stem with slender roots or forming callus with stout roots. Germination
also affected embryo orientation in culture; placing embryos upright on the medium was most beneficial for germination. The
in vitro-germinated seedlings were acclimatized in soil under shady conditions with a survival rate of 60–70%. These plants
were phenotypically normal, healthy, and similar to donor plants. This protocol will be useful for overcoming seed dormancy
and for rapid multiplication and conservation of G. rottleriformis using zygotic embryo culture. 相似文献