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171.
172.
Molecular biology and pathogenesis of hepatitis E virus 总被引:1,自引:0,他引:1
The hepatitis E virus (HEV) is a small RNA virus and the etiological agent for hepatitis E, a form of acute viral hepatitis.
The virus has a feco-oral transmission cycle and is transmitted through environmental contamination, mainly through drinking
water. Recent studies on the isolation of HEV-like viruses from animal species also suggest zoonotic transfer of the virus.
The absence of small animal models of infection and efficient cell culture systems has precluded virological studies on the
replication cycle and pathogenesis of HEV. A vaccine against HEV has undergone successful clinical testing and diagnostic
tests are available. This review describes HEV epidemiology, clinical presentation, pathogenesis, molecular virology and the
host response to HEV infection. The focus is on published literature in the past decade.
Equal contribution 相似文献
173.
Adhyayan Sharan Shikha Nandan S. Darmwal 《World journal of microbiology & biotechnology》2008,24(12):3087-3090
The phosphate solubilization activity of Xanthomonas campestris was measured in both the wild type and mutant strains using various carbon and nitrogen sources. Glucose was found to be
the best in both (wild 39.9%; mutant 67.1%) strains followed by sucrose (46.8%) in the mutant and molasses (36.0%) in the
wild type. Ammonium sulphate was the best nitrogen source for both the strains, followed by ammonium nitrate and urea. Dicalcium
phosphate (DCP) was solubilized maximally by both the strains followed by tricalcium phosphate (TCP) and rock phosphate (RP)
when various concentrations of different phosphate sources were tested. 相似文献
174.
175.
176.
B P Enright M Taneja D Schreiber J Riesen X C Tian J E Fortune X Yang 《Biology of reproduction》2002,66(2):291-296
This study examined the onset of puberty, follicular dynamics, reproductive hormone profiles, and ability to maintain pregnancy in cloned heifers produced by somatic cell nuclear transfer. Four adult somatic cell-cloned heifers, derived from a 13-yr-old Holstein cow, were compared to 4 individual age- and weight-matched heifers produced by artificial insemination (AI). From 7 to 9 mo of age, jugular venous blood samples were collected twice weekly, and from 10 to 11 or 12 mo of age, blood sampling was carried out every other day. After the heifers reached puberty (defined as the first of 3 consecutive blood samples with peripheral plasma progesterone concentrations of >1 ng/ml), ultrasound examination of ovaries and jugular plasma sample collection were carried out daily for 1 estrous cycle. Cloned heifers reached puberty later than controls (mean +/- SEM, 314.7 +/- 9.6 vs. 272 +/- 4.4 days and 336.7 +/- 13 vs. 302.8 +/- 4.5 kg for clones and controls, respectively; P < 0.05). However, cloned and control heifers were not different in estrous cycle length, ovulatory follicle diameter, number of follicular waves, or profiles of hormonal changes (LH, FSH, estradiol, and progesterone). Three of the 4 clones and all 4 control heifers became pregnant after AI. These results demonstrate that clones from an aged adult have normal reproductive development. 相似文献
177.
Saxena S Kumar GR Singh P Chaturvedi U Saxena L Kumar R Sahoo AP Doley J Rajmani Kumar A Kumar S Tiwari AK 《Indian journal of experimental biology》2012,50(5):325-331
In the present study recombinant VP3 (rVP3) was expressed in E. coli BL21 (DE3) (pLysS) and its polyclonal antibodies were characterized. SDS-PAGE analysis revealed that the expression of recombinant protein was maximum when induced with 1.5 mM IPTG for 6 h at 37 degrees C. The 6xHis-tagged fusion protein was purified on Ni-NTA and confirmed by Western blot using CAV specific antiserum. Rabbits were immunized with purified rVP3 to raise anti-VP3 polyclonal antibodies. Polyclonal serum was tested for specificity and used for confirming expression of VP3 in HeLa cells transfected with pcDNA.cav.vp3 by indirect fluorescent antibody test (IFAT), flow cytometry and Western blot. Available purified rVP3 and polyclonal antibodies against VP3 may be useful to understand its functions which may lead to application of VP3 in cancer therapeutics. 相似文献
178.
Prof. Dr. Indra Bir Singh Pradeep Srivastava Shikha Sharma Maneesh Sharma Dhruv Sen Singh Dr. Govindaraja Rajagopalan Dr. Uma Kant Shukla 《Facies》1999,40(1):197-210
Summary Major alluvial plains contain large tracts of fine-grained muddy sediments, deposited away from the main river channels, which
are mostly classed as overbank or floodplain deposits. Systematic study of the Ganga plain shows that such large tracts of
deposition of muddy sediments are located several metres above the major channels, and are not flooded by overtopping of the
major river channels. These surfaces are here designated as upland interfluve areas (Doab) where deposition of fine-grained
sediments takes place independent of the processes operating in the main channels. The surfaces show distinct depositional
domains with characteristic deposits. These include higher sloping surfaces (mottled silt), lower flat surfaces (variegated
clayey silt), gulleys (sandy silt), small channels (mottled silty sand), ponds (shelly sandy clayey silt), lakes (shelly clayey
silt). These deposits are prone to diagenetic changes, especially the development of calcrete horizons. Redistribution of
these domains through time produces characteristic mud-dominant alluvial stratigraphy as observed in the Late Quaternary deposits
of the Ganga plain. This succession shows similarity to mud-dominant deposits of the Siwalik succession. These Doab deposits
are distinct from the overbank deposits formed close to the river channels affected by channel processes. It is argued that
many of the thick mud-dominant fluvial deposits of the ancient fluvial record are products of deposition in upland interfluve
areas. 相似文献
179.
Bacteria express certain of their characteristics especially, pathogenicity factors at high cell densities. The process is termed as quorum sensing (QS). QS operates via signal molecules such as acylhomoserine lactones (AHLs). Other bacteria inhibit QS through the inactivation of AHL signals by producing enzymes like AHL-lactonases and -acylases. Comparative genomic analysis has revealed the multiplicity of genes for AHL lactonases (up to 12 copies per genome) among Bacillus spp. and that of AHL-acylases (up to 5 copies per genome) among Pseudomonas spp. This genetic evolution can be envisaged to enable host to withstand the attacks from bacterial population, which regulates its functioning through QS. 相似文献
180.