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951.
Hepatitis C Virus Infection Modulates Expression of Interferon Stimulatory Gene IFITM1 by Upregulating miR-130A 总被引:1,自引:0,他引:1
J Bhanja Chowdhury S Shrivastava R Steele AM Di Bisceglie R Ray RB Ray 《Journal of virology》2012,86(18):10221-10225
We have examined the underlying mechanism of hepatitis C virus (HCV)-mediated IFITM1 regulation. IFITM1 is a potential target of miR-130a. Our results demonstrated that miR-130a expression was significantly higher in HCV-infected hepatocytes and liver biopsy specimens than in controls. Introduction of anti-miR-130a in hepatocytes increased IFITM1 expression. Hepatocytes stably expressing IFITM1 reduced HCV replication. Together, these results suggested that HCV infection of hepatocytes upregulates miR-130a and that use of anti-miR-130a may have potential for restriction of HCV replication. 相似文献
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Flores-Villaseñor H Canizalez-Román A de la Garza M Nazmi K Bolscher JG Leon-Sicairos N 《Biochimie》2012,94(9):1935-1942
Enteropathogenic Escherichia coli (EPEC) is an important cause of infant diarrhea in developing countries. It produces a characteristic intestinal histopathological lesion on enterocytes known as ‘attaching and effacing’ (A/E), and these two steps are mediated by a type-III secretory system. In the present study, we evaluated the effect on the initial host cell attachment step produced by bovine lactoferrin (bLF) and three synthetic peptides: lactoferricin (LFcin), lactoferrampin (LFampin) and LFchimera. A special focus was given to the hemolytic activity and EPEC-induced actin polymerization in HEp-2 cells, as well as to the espA gene expression, which produces the protein responsible for primary contact with the host cells. Results show that EPEC attachment to HEp-2 cells was significantly suppressed by bLF and LFchimera at 125 and 40 μM, respectively. EPEC-mediated actin polymerization was blocked by bLF and LFchimera at 88 and 99%, respectively. LFchimera inhibited the attachment and A/E lesion caused by EPEC in a dose-dependent manner. In the presence of 125 μM bLF, the expression level of the espA gene was decreased by 50% compared to the untreated control. LFchimera at concentrations of 20 μM and 40 μM diminished the level of espA gene expression 100 and 1000 fold, respectively (P < 0.001). Although bLF, LFchimera, LFcin, and LFampin all significantly blocked the hemolysis produced by EPEC (P < 0.001), the two former compounds produced this effect at lower concentrations. These two compounds, bLF and LFchimera, were able to inhibit the first steps of the mechanism of the damage used by EPEC. This data suggests that LFchimera could provide protection against enteropathogens that share this mechanism. 相似文献
955.
Phulwinder K. Grover Adrian G. Cummins Timothy J. Price Ian C. Roberts-Thomson Jennifer E. Hardingham 《Biochimie》2012
Understanding the molecular basis of disease requires gene expression profiling of normal and pathological tissue. Although the advent of laser microdissection (LMD) has greatly facilitated the procurement of specific cell populations, often only small amounts of low quality RNA is recovered. This precludes the use of global approaches of gene expression profiling which require sizable amounts of high quality RNA. Here we report a method for processing of snap-frozen tissue to prepare large amounts of intact RNA using LMD. 相似文献
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The complete mitochondrial genomes of five tiger samples from three subspecies (P. t. sumatrae, P. t. altica, and P. t. tigris) were successfully obtained by using 26 specifically designed Panthera-specific primer sets. The genome organization and gene arrangement of the five tiger samples were similar to each other;
however polymorphic tandem repeat sequences were observed in the control region (CR). This led to a difference in the genome
lengths obtained from these five samples with an average size of 16,994 bp for the five tiger mitochondrial genomes. The nucleotide
base composition was on average as follows: A, 31.8%; T, 27.0%; C, 26.6%; G, 14.6% and exhibited compositional asymmetry.
Most of tiger mitochondrial genome characteristics are similar to those of other common vertebrate species; however, some
distinctive features were observed in the CR. First, the repetitive sequence 2 (RS 2) contained two repeat units of 80 bp
and the first 15 bp of what would be the third repeat motif. The repetitive sequence 3 (RS 3) contained 47–50 repeat motifs
of a shorter 8 bp (ACGTAYAC)n. Second, length heteroplasmy polycystosine (poly-C) stretches was observed at the end of the HV I locus in all tiger samples. 相似文献
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AS Whiteley S Jenkins I Waite N Kresoje H Payne B Mullan R Allcock A O'Donnell 《Journal of microbiological methods》2012,91(1):80-88
Here we demonstrate a cost effective and scalable microbial ecology sequencing platform using the Ion Torrent Personal Genome Machine (PGM). We assessed both PCR amplified 16S rRNA and shotgun metagenomic approaches and generated 100,000+ to 1,000,000+ reads using 'post-light' based sequencing technology within different sized semi-conductor chips. Further development of Golay barcoded Ion Tags allowed multiplex analyses of microbial communities with substantially reduced costs compared with platforms such as 454/GS-FLX. Using these protocols we assessed the bacterial and archaeal dynamics within covered anaerobic digesters used to treat piggery wastes. Analysis of these sequence data showed that these novel methanogenic waste treatment systems are dominated by bacterial taxa, in particular Clostridium, Synergistia and Bacteroides that were maintained as a stable community over extended time periods. Archaeal community dynamics were more stochastic with the key methanogenic taxa more difficult to resolve, principally due to the poor congruence seen between community structures generated either by nested PCR or metagenomic approaches for archaeal analyses. Our results show that for microbial community structure and function analyses, the PGM platform provides a low cost, scalable and high throughput solution for both Tag sequencing and metagenomic analyses. 相似文献
960.
Pippa J. Chapman Sheila M. Palmer Brian J. Irvine Gordon Mitchell Adrian T. McDonald 《Biogeochemistry》2012,111(1-3):105-109