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1.
Zhongyuan Liu Yun Wang Guodong Lü Xianlei Wang Fuchun Zhang Ji Ma 《Frontiers of Biology in China》2008,3(3):279-286
Partial cDNA sequences coding for antifreeze proteins in Tenebrio molitor were obtained by RT-PCR. Sequence analysis revealed nine putative cDNAs with a high degree of homology to Tenebrio molitor antifreeze protein genes published in GenBank. The recombinant pGEX-4T-1-tmafp-XJ430 was introduced into E. coli BL21 to induce a GST fusion protein by IPTG. SDSPAGE analysis for the fusion protein shows a band of 38 kDa. pCDNA3-tmafp-XJ430 was injected into mice to generate antiserum which was later detected by indirect ELISA. The titer of the antibody
was 1:2000.Western blotting analysis shows that the antiserum was specifically against the antifreeze protein. Our results
laid the foundation for further studies on the properties and functions of insect antifreeze proteins.
__________
Translated from Hereditas (Beijing), 2006, 28(12): 1532-1540 [译自: 遗传] 相似文献
2.
Determination of baseline susceptibility to Cry1Ab protein for Asian corn borer (Lep., Crambidae) 总被引:1,自引:0,他引:1
Abstract: Although transgenic Bacillus thuringiensis (Bt) corn can provide a new tool for control of the Asian corn borer (ACB), Ostrinia furnacalis (Guenée), concern has been raised regarding the possibility of the target insect evolving resistance to the Bt protein under intensive selection pressure from Bt corn. Therefore, it is necessary to establish baseline data to enable detection of changes in susceptibility in field populations after prolonged exposure to Bt corn. Susceptibility to purified Cry1Ab protein from Bt was determined for 10 populations of ACB from the major corn‐growing regions of China, ranging geographically from Heilongjiang Province in the northeast to Shaanxi Province in the east‐central part. Neonate ACB were exposed to semi‐artificial diet incorporated with increasing Cry1Ab protein concentrations, and mortality and growth inhibition were evaluated after 7 days. The range of LC50 (50% lethal concentration) among the populations was 0.10 to 0.81 μg/g (Cry1Ab protein/diet). Differences (P < 0.05) in susceptibility among the populations were significant. LC50s generated from the Huanghuaihai Summer Corn Region were higher than those from the Spring Corn Regions. Bt was one of the significant natural biomortality factors of overwintering generation ACB. There was a significant correlation between percentage of the larvae infected with Bt and their LC50 values to Cry1Ab protein in geographic distinct populations (r = 0.7350*, d.f. = 8, r0.05 = 0.632). Based on the background of Bt formulations used for corn insect pests control in these areas, these differences were not caused by prior exposure to Bt insecticides. Instead, the small differences likely reflect natural Bt selection pressure. Because the variation in susceptibility to Cry1Ab was small (<10‐fold), the ACB apparently is susceptible to Cry1Ab across its range within China. 相似文献
3.
Zhang W Ding T Zhang J Su J Li F Liu X Ma W Yao L 《Molecular and cellular biochemistry》2006,290(1-2):43-53
Discoidin domain receptor 2 (DDR2) is a kind of protein tyrosine kinases associated with cell proliferation and tumor metastasis,
and collagen, identified as a ligand for DDR2, up-regulates matrix metallloproteinase 1 (MMP-1) and MMP-2 expression in cellular
matrix. To investigate the roles of DDR2 in destruction of cartilage in rheumatoid arthritis (RA) and tumor metastasis, we
tried to express extracellular domain of DDR2 fused with a His tag to increase protein solubility and facilitate purification
(without signal peptide and transmembrane domain, designated DR) in Pichia pastoris, purify the expressed protein, and characterize its function, for purpose of future application as a specific DDR2 antagonist.
Two clones of relative high expression of His-DR were obtained, After purification by a Ni-NTA (nitric-tri-acetic acid) chromatographic
column, soluble fused His-DR over 90% purity were obtained. Competitive binding inhibition assay demonstrated that expressed
His-DR could block the binding of DDR2 and natural DDR2 receptors on NIT3T3 and synovial cell surfaces. Results of RT-PCR,
Western blotting, and gelatinase zymography showed that His-DR was capable of inhibiting MMP-1 and MMP-2 secretion from NIT3T3
cells and RA synoviocytes stimulated by collagen II. For MMP-1, the inhibitory effect was displayed at the levels of mRNA
and protein, whereas for MMP-2 it was demonstrated at the level of protein physiological activity. All these findings suggested
that the fused expressed His-DR inhibited the activity of natural DDR2, and relevant MMP-1 and MMP-2 expression in synoviocytes
and NIH3T3 cells provoked by collagen II.
Wei Zhang and Tianbing Ding equally contributed to this work. 相似文献
4.
Swida A Czarna M Woyda-Płoszczyca A Kicinska A Sluse FE Jarmuszkiewicz W 《Journal of bioenergetics and biomembranes》2007,39(1):109-115
A profile of free fatty acid (FFA) specificity in Acanthamoeba castellanii mitochondrial uncoupling is described. The FFA uncoupling specificity was observed as different abilities to stimulate resting
respiration, to decrease resting membrane potential, and to decrease oxidative phosphorylation efficiency. Tested unsaturated
FFA (C18–20) were more effective as uncouplers and protonophores when compared to tested saturated FFA (C8–18), with palmitic
acid (C16:0) as the most active. As FFA efficiency in mitochondrial uncoupling is related to physiological changes of fatty
acid composition (and thereby FFA availability) during growth of amoeba cells, it could be a way to regulate the activity
of an uncoupling protein and thereby the efficiency of oxidative phosphorylation during a cell life of this unicellular organism.
Aleksandra Swida and Małgorzata Czarna contributed equally to this work. 相似文献
5.
Zhao D Yang X Quan L Timofejeva L Rigel NW Ma H Makaroff CA 《Plant molecular biology》2006,62(1-2):99-110
Nuclear reorganization and juxtaposition of homologous chromosomes at late leptotene/early zygotene are essential steps before chromosome synapsis at pachytene. We report the results of detailed studies, which demonstrate that nuclear reorganization and homolog juxtapositioning processes are defective in a null mutant, ask1-1. Our results from 4, 6-diamino-2-phenylindole (DAPI)-stained spreads showed that the “synizetic knot”, which is typically found in wild type (WT) meiosis during late leptotene and zygotene, was missing in the ask1-1 mutant. Furthermore, ask1-1 meiocytes exhibited only limited homolog juxtaposition at centromere regions at early zygotene. Immunodetection of the cohesin protein SYN1 identified ask1 defects in cohesin distribution from zygotene to anaphase I. Analysis of meiotic chromosomes in ask1-1 and syn1 single mutants, as well as an ask1-1 syn1 double mutant indicate that ASK1 is required for normal SYN1 distribution during meiotic prophase I and suggest that ask1 associated defects may be primarily related to SYN1 mislocalization. 相似文献
6.
Mehul S. Suthar Daphne Y. Ma Sunil Thomas Jennifer M. Lund Nu Zhang Stephane Daffis Alexander Y. Rudensky Michael J. Bevan Edward A. Clark Murali-Krishna Kaja Michael S. Diamond Michael Gale Jr 《PLoS pathogens》2010,6(2)
The innate immune response is essential for controlling West Nile virus (WNV) infection but how this response is propagated and regulates adaptive immunity in vivo are not defined. Herein, we show that IPS-1, the central adaptor protein to RIG-I-like receptor (RLR) signaling, is essential for triggering of innate immunity and for effective development and regulation of adaptive immunity against pathogenic WNV. IPS-1−/− mice exhibited increased susceptibility to WNV infection marked by enhanced viral replication and dissemination with early viral entry into the CNS. Infection of cultured bone-marrow (BM) derived dendritic cells (DCs), macrophages (Macs), and primary cortical neurons showed that the IPS-1-dependent RLR signaling was essential for triggering IFN defenses and controlling virus replication in these key target cells of infection. Intriguingly, infected IPS-1−/− mice displayed uncontrolled inflammation that included elevated systemic type I IFN, proinflammatory cytokine and chemokine responses, increased numbers of inflammatory DCs, enhanced humoral responses marked by complete loss of virus neutralization activity, and increased numbers of virus-specific CD8+ T cells and non-specific immune cell proliferation in the periphery and in the CNS. This uncontrolled inflammatory response was associated with a lack of regulatory T cell expansion that normally occurs during acute WNV infection. Thus, the enhanced inflammatory response in the absence of IPS-1 was coupled with a failure to protect against WNV infection. Our data define an innate/adaptive immune interface mediated through IPS-1-dependent RLR signaling that regulates the quantity, quality, and balance of the immune response to WNV infection. 相似文献
7.
8.
Adam C. Naj Honghuang Lin Badri N. Vardarajan Simon White Daniel Lancour Yiyi Ma Michael Schmidt Fangui Sun Mariusz Butkiewicz William S. Bush Brian W. Kunkle John Malamon Najaf Amin Seung Hoan Choi Kara L. Hamilton-Nelson Sven J. van der Lee Namrata Gupta Daniel C. Koboldt Anita L. DeStefano 《Genomics》2019,111(4):808-818
The Alzheimer's Disease Sequencing Project (ADSP) performed whole genome sequencing (WGS) of 584 subjects from 111 multiplex families at three sequencing centers. Genotype calling of single nucleotide variants (SNVs) and insertion-deletion variants (indels) was performed centrally using GATK-HaplotypeCaller and Atlas V2. The ADSP Quality Control (QC) Working Group applied QC protocols to project-level variant call format files (VCFs) from each pipeline, and developed and implemented a novel protocol, termed “consensus calling,” to combine genotype calls from both pipelines into a single high-quality set. QC was applied to autosomal bi-allelic SNVs and indels, and included pipeline-recommended QC filters, variant-level QC, and sample-level QC. Low-quality variants or genotypes were excluded, and sample outliers were noted. Quality was assessed by examining Mendelian inconsistencies (MIs) among 67 parent-offspring pairs, and MIs were used to establish additional genotype-specific filters for GATK calls. After QC, 578 subjects remained. Pipeline-specific QC excluded ~12.0% of GATK and 14.5% of Atlas SNVs. Between pipelines, ~91% of SNV genotypes across all QCed variants were concordant; 4.23% and 4.56% of genotypes were exclusive to Atlas or GATK, respectively; the remaining ~0.01% of discordant genotypes were excluded. For indels, variant-level QC excluded ~36.8% of GATK and 35.3% of Atlas indels. Between pipelines, ~55.6% of indel genotypes were concordant; while 10.3% and 28.3% were exclusive to Atlas or GATK, respectively; and ~0.29% of discordant genotypes were. The final WGS consensus dataset contains 27,896,774 SNVs and 3,133,926 indels and is publicly available. 相似文献
9.
Wu Qingru Li Bingxin Li Ying Liu Fenfen Yang Lin Ma Yongjiang Zhang Yuan Xu Danning Li Yugu 《Functional & integrative genomics》2022,22(5):849-863
Functional & Integrative Genomics - Polysaccharides from Atractylodes macrocephala Koidz (PAMK) can promote the proliferation of thymocytes and improve the body’s immunity. However, the... 相似文献
10.
The rat beta 1-adrenergic receptor (beta 1-AR) gene contains glucocorticoid response element (GRE) half-sites at positions -2767 and -945. In electrophoretic mobility shift assay (EMSA) experiments, neither beta 1-AR GRE half-site recognized glucocorticoid receptors (GRs) obtained from baculovirus high-level expression systems or from mammalian cells. We have developed a sensitive UV cross-linking/immunoprecipitation assay, using a 524-bp fragment containing the prototypical GRE obtained from the rat tyrosine aminotransferase promoter sequence and using antibodies recognizing mammalian GR. Using this assay, we provide evidence that rat beta 1-AR gene sequences recognize mammalian GRs expressed in mouse 3T3 cells and that the site of GR interaction does not appear to specifically contain the beta 1-AR GRE half-sites. This represents one of the first reports demonstrating the utility of a UV cross-linking/immunoprecipitation assay in the detection of mammalian GR interaction with beta 1-AR sequences, is consistent with the lack of specific DNA-GR protein complexes observed in EMSA experiments using oligonucleotide probes containing the beta 1-AR GRE half-sites, and provides evidence that mammalian GR interaction occurs at complex rate beta 1-AR gene sequences. 相似文献