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911.
Ibne Ali Vikrant Singh Chouhan Satyaveer Singh Dangi Mahesh Gupta Ujjwala Tandiya Iqbal Hyder Vijay Pratap Yadav Rudra Prasanna Panda Vazhoor Babitha Vimla Nagar Arvind Sonwane Firdous Ahmad Khan Bikash Chandra Das Gyanendra Singh Sadhan Bag Mihir Sarkar 《Theriogenology》2014
Recent experiments using expression, immunolocalization, and cell culture approaches have provided leading insights into regulation of luteal angiogenesis by different growth factor systems and its role in the function of corpus luteum (CL) in buffalo. On the contrary, lymphangiogenesis and its regulation in the CL are still poorly understood. The aim of this study was to evaluate the expression and localization of lymphangiogenic factors (vascular endothelial growth factor [VEGF]-C and VEGFD), their receptor (VEGFR3), and lymphatic endothelial marker (LYVE1) in bubaline CL during different stages of the estrous cycle and to investigate functional role of VEGFC and VEGFD in luteal lymphangeogenesis. The mRNA and protein expression of VEGFC, VEGFD, and VEGFR3 was significantly greater in mid and late luteal phases, which correlated well with the expression of LYVE1. The lymphangiogenic factors were localized in luteal cells, exclusively in the cytoplasm. Immunoreactivity of VEGFC was greater during midluteal phase and that of VEGFD was greater during the mid and late luteal phases. Luteal cells were cultured in vitro and treated for different time duration (24, 48, and 72 hours) with VEGFC and VEGFD each at 50, 100, and 150 ng/mL concentration and VEGFC with VEGFD at 100 ng/mL concentration. The temporal increase in LYVE1 mRNA expression was significant (P < 0.05) in VEGFC and VEGFC with VEGFD treatment and no significant change was seen in VEGFD treatment. Thus, it seems likely that VEGFD itself has little role in lymphangiogenesis but along with VEGFC it might have a synergistic effect on VEGFR3 receptors for inducing lymphangiogenesis. In summary, the present study provided evidence that VEGFC and VEGFD, and their receptor VEGFR3, are expressed in bubaline CL and are localized exclusively in the cell cytoplasm, suggesting that these factors have a functional role in lymphangiogenesis of CL in buffalo. 相似文献
912.
Ali G Lee K Andrade PB Basit S Santos-Cortez RL Chen L Jelani M Ansar M Ahmad W Leal SM 《Human heredity》2011,71(2):106-112
A novel locus DFNB90 was mapped to 7p22.1-p15.3 by carrying out a genome scan in a multigenerational consanguineous family from Pakistan with autosomal recessive nonsyndromic hearing impairment (ARNSHI).DFNB90 is the eighth ARNSHI locus mapped to chromosome 7. A multipoint LOD score of 4.0 was obtained at a number of SNP marker loci spanning from rs1468996 (chromosome 7: 5.7 Mb) tors957960 (chromosome 7: 18.8 Mb). The 3-unit support interval and the region of homozygosity for DFNB90 spans from markers rs1553960 (chromosome 7: 4.9 Mb) to rs206198 (chromosome 7: 20.3 Mb). Candidate genes ACTB, BZW, OCM, MACC1, NXPH1, PRPS1L1, RAC1 and RPA3, which lie within the DFNB90 region, were sequenced and no potentially causal variants were identified. 相似文献
913.
Lorenzen I Trad A Grötzinger J 《Biochemical and biophysical research communications》2011,(2):330-336
A disintegrin and metalloprotease protein 17 (ADAM17) is a transmembrane zinc dependent metalloprotease. The catalytic activity of the enzyme results in the shedding of a broad range of membrane proteins. The release of the corresponding ectodomains induces a switch in various physiological and pathophysiological processes. So far there is not much information about the molecular mechanism of ADAM17 activation available. As for other transmembrane proteases, multimerisation may play a critical role in the activation and function of ADAM17. The present work demonstrates that ADAM17 indeed exists as a multimer in the cell membrane and that this multimerisation is mediated by its EGF-like domain. 相似文献
914.
Saheem Ahmad Moinuddin Kiran Dixit Uzma Shahab Khursheed Alam Asif Ali 《Biochemical and biophysical research communications》2011,407(3):568
The highly reactive electrophile, methylglyoxal (MG), a break down product of carbohydrates, is a major environmental mutagen having potential genotoxic effects. Previous studies have suggested the reaction of MG with free amino groups of proteins forming advanced glycation end products (AGEs). This results in the generation of free radicals which play an important role in pathophysiology of aging and diabetic complications. MG also reacts with free amino group of nucleic acids resulting in the formation of DNA–AGEs. While the formation of nucleoside AGEs has been demonstrated previously, no extensive studies have been performed to assess the genotoxicity and immunogenicity of DNA–AGEs. In this study we report both the genotoxicity and immunogenicity of AGEs formed by MG–Lys–Cu2+ system. Genotoxicity of the experimentally generated AGEs was confirmed by comet-assay. Spectroscopical analysis and melting temperature studies suggest structural perturbations in the DNA as a result of modification. This might be due to generation of single-stranded regions and destabilization of hydrogen bonds. Immunogenicity of native and MG–Lys–Cu2+-DNA was probed in female rabbits. The modified DNA was highly immunogenic eliciting high titre immunogen specific antibodies, while the unmodified form was almost non-immunogenic. The results show structural perturbations in MG–Lys–Cu2+-DNA generating new epitopes that render the molecule immunogenic. 相似文献
915.
We have employed a rapid fluorescence-based screen to assess the polyspecificity of several aminoacyl-tRNA synthetases (aaRSs) against an array of unnatural amino acids. We discovered that a p-cyanophenylalanine specific aminoacyl-tRNA synthetase (pCNF-RS) has high substrate permissivity for unnatural amino acids, while maintaining its ability to discriminate against the 20 canonical amino acids. This orthogonal pCNF-RS, together with its cognate amber nonsense suppressor tRNA, is able to selectively incorporate 18 unnatural amino acids into proteins, including trifluoroketone-, alkynyl-, and halogen-substituted amino acids. In an attempt to improve our understanding of this polyspecificity, the X-ray crystal structure of the aaRS-p-cyanophenylalanine complex was determined. A comparison of this structure with those of other mutant aaRSs showed that both binding site size and other more subtle features control substrate polyspecificity. 相似文献
916.
Lin AP Demeler B Minard KI Anderson SL Schirf V Galaleldeen A McAlister-Henn L 《Biochemistry》2011,50(2):230-239
Yeast NAD(+)-specific isocitrate dehydrogenase (IDH) is an octameric enzyme composed of four heterodimers of regulatory IDH1 and catalytic IDH2 subunits. The crystal structure suggested that the interactions between tetramers in the octamer are restricted to defined regions in IDH1 subunits from each tetramer. Using truncation and mutagenesis, we constructed three tetrameric forms of IDH. Truncation of five residues from the amino terminus of IDH1 did not alter the octameric form of the enzyme, but this truncation with an IDH1 G15D or IDH1 D168K residue substitution produced tetrameric enzymes as assessed by sedimentation velocity ultracentrifugation. The IDH1 G15D substitution in the absence of any truncation of IDH1 was subsequently found to be sufficient for production of a tetrameric enzyme. The tetrameric forms of IDH exhibited ~50% reductions in V(max) and in cooperativity with respect to isocitrate relative to those of the wild-type enzyme, but they retained the property of allosteric activation by AMP. The truncated (-5)IDH1/IDH2 and tetrameric enzymes were much more sensitive than the wild-type enzyme to inhibition by the oxidant diamide and concomitant formation of a disulfide bond between IDH2 Cys-150 residues. Binding of ligands reduced the sensitivity of the wild-type enzyme to diamide but had no effect on inhibition of the truncated or tetrameric enzymes. These results suggest that the octameric structure of IDH has in part evolved for regulation of disulfide bond formation and activity by ensuring the proximity of the amino terminus of an IDH1 subunit of one tetramer to the IDH2 Cys-150 residues in the other tetramer. 相似文献
917.
Shin YS Remacle F Fan R Hwang K Wei W Ahmad H Levine RD Heath JR 《Biophysical journal》2011,(10):2378-2386
Protein signaling networks among cells play critical roles in a host of pathophysiological processes, from inflammation to tumorigenesis. We report on an approach that integrates microfluidic cell handling, in situ protein secretion profiling, and information theory to determine an extracellular protein-signaling network and the role of perturbations. We assayed 12 proteins secreted from human macrophages that were subjected to lipopolysaccharide challenge, which emulates the macrophage-based innate immune responses against Gram-negative bacteria. We characterize the fluctuations in protein secretion of single cells, and of small cell colonies (n = 2, 3,···), as a function of colony size. Measuring the fluctuations permits a validation of the conditions required for the application of a quantitative version of the Le Chatelier's principle, as derived using information theory. This principle provides a quantitative prediction of the role of perturbations and allows a characterization of a protein-protein interaction network. 相似文献
918.
Despite the great importance of Aureobasidium pullulans in biotechnology, the fungus had emerged as an opportunistic human pathogen, especially among immunocompromised patients.
Clinical detection of this rare human fungal pathogen presently relies on morphology diagnosis which may be misleading. Thus,
a sensitive and accurate quantitative molecular assay for A. pullulans remains lacking. In this study, we presented the microscopy observations of A. pullulans that reveals the phenotypic plasticity of the fungus. A. pullulans-specific primers and molecular beacon probes were designed based on the fungal 18S ribosomal RNA (rRNA) gene. Comparison
of two probes with varied quencher chemistry, namely BHQ-1 and Tamra, revealed high amplification efficiency of 104% and 108%,
respectively. The optimized quantitative real-time PCR (qPCR) assays could detect and quantify up to 1 pg concentration of
A. pullulans DNA. Both assays displayed satisfactory performance parameters at fast thermal cycling mode. The molecular assay has great
potential as a molecular diagnosis tool for early detection of fungal infection caused by A. pullulans, which merits future study in clinical diagnosis. 相似文献
919.
920.