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91.
Prajna Jena Soumitra Mohanty Tirthankar Mohanty Stephanie Kallert Matthias Morgelin Thomas Lindstr?m Niels Borregaard Steffen Stenger Avinash Sonawane Ole E. S?rensen 《PloS one》2012,7(12)
Pathogenic mycobacteria reside in, and are in turn controlled by, macrophages. However, emerging data suggest that neutrophils also play a critical role in innate immunity to tuberculosis, presumably by their different antibacterial granule proteins. In this study, we purified neutrophil azurophil and specific granules and systematically analyzed the antimycobacterial activity of some purified azurophil and specific granule proteins against M. smegmatis, M. bovis-BCG and M. tuberculosis H37Rv. Using gel overlay and colony forming unit assays we showed that the defensin-depleted azurophil granule proteins (AZP) were more active against mycobacteria compared to other granule proteins and cytosolic proteins. The proteins showing antimycobacterial activity were identified by MALDI-TOF mass spectrometry. Electron microscopic studies demonstrate that the AZP disintegrate bacterial cell membrane resulting in killing of mycobacteria. Exogenous addition of AZP to murine macrophage RAW 264.7, THP-1 and peripheral blood monocyte-derived macrophages significantly reduced the intracellular survival of mycobacteria without exhibiting cytotoxic activity on macrophages. Immunofluorescence studies showed that macrophages actively endocytose neutrophil granular proteins. Treatment with AZP resulted in increase in co-localization of BCG containing phagosomes with lysosomes but not in increase of autophagy. These data demonstrate that neutrophil azurophil proteins may play an important role in controlling intracellular survival of mycobacteria in macrophages. 相似文献
92.
V Anand N Dogra S Singh SN Kumar MK Jena D Malakar AK Dang BP Mishra TK Mukhopadhyay JK Kaushik AK Mohanty 《PloS one》2012,7(7):e40469
Background
The objective of this study was to establish the buffalo mammary epithelial cell line (BuMEC) and characterize its mammary specific functions.Methodology
Buffalo mammary tissue collected from the slaughter house was processed enzymatically to obtain a heterogenous population of cells containing both epithelial and fibroblasts cells. Epithelial cells were purified by selective trypsinization and were grown in a plastic substratum. The purified mammary epithelial cells (MECs) after several passages were characterized for mammary specific functions by immunocytochemistry, RT-PCR and western blot.Principal Findings
The established buffalo mammary epithelial cell line (BuMEC) exhibited epithelial cell characteristics by immunostaining positively with cytokeratin 18 and negatively with vimentin. The BuMEC maintained the characteristics of its functional differentiation by expression of β-casein, κ-casein, butyrophilin and lactoferrin. BuMEC had normal growth properties and maintained diploid chromosome number (2n = 50) before and after cryopreservation. A spontaneously immortalized buffalo mammary epithelial cell line was established after 20 passages and was continuously subcultured for more than 60 passages without senescence.Conclusions
We have established a buffalo mammary epithelial cell line that can be used as a model system for studying mammary gland functions. 相似文献93.
The fact that malaria is still an uncontrolled disease is reflected by the genetic organization of the parasite genome. Efforts to curb malaria should begin with proper understanding of the mechanism by which the parasites evade human immune system and evolve resistance to different antimalarial drugs. We have initiated such a study and presented herewith the results from the in silico understanding of a seventh chromosomal region of the malarial parasite Plasmodium falciparum encompassing the antigenic var genes (coding pfemp1) and the drug-resistant gene pfcrt located at a specified region of the chromosome 7. We found 60 genes of various functions and lengths, majority (61.67%) of them were performing known functions. Almost all the genes have orthologs in other four species of Plasmodium, of which P. chabaudi seems to be the closest to P. falciparum. However, only two genes were found to be paralogous. Interestingly, the drug-resistant gene, pfcrt was found to be surrounded by seven genes coding for several CG proteins out of which six were reported to be responsible for providing drug resistance to P. vivax. The intergenic regions, in this specified region were generally large in size, majority (73%) of them were of more than 500 nucleotide bp length. We also designed primers for amplification of 21 noncoding DNA fragments in the whole region for estimating genetic diversity and inferring the evolutionary history of this region of P. falciparum genome. 相似文献
94.
Ghosh R Chhabra A Phatale PA Samrat SK Sharma J Gosain A Mohanty D Saran S Gokhale RS 《The Journal of biological chemistry》2008,283(17):11348-11354
Dictyostelium discoideum exhibits the largest repository of polyketide synthase (PKS) proteins of all known genomes. However, the functional relevance of these proteins in the biology of this organism remains largely obscure. On the basis of computational, biochemical, and gene expression studies, we propose that the multifunctional Dictyostelium PKS (DiPKS) protein DiPKS1 could be involved in the biosynthesis of the differentiation regulating factor 4-methyl-5-pentylbenzene-1,3-diol (MPBD). Our cell-free reconstitution studies of a novel acyl carrier protein Type III PKS didomain from DiPKS1 revealed a crucial role of protein-protein interactions in determining the final biosynthetic product. Whereas the Type III PKS domain by itself primarily produces acyl pyrones, the presence of the interacting acyl carrier protein domain modulates the catalytic activity to produce the alkyl resorcinol scaffold of MPBD. Furthermore, we have characterized an O-methyltransferase (OMT12) from Dictyostelium with the capability to modify this resorcinol ring to synthesize a variant of MPBD. We propose that such a modification in vivo could in fact provide subtle variations in biological function and specificity. In addition, we have performed systematic computational analysis of 45 multidomain PKSs, which revealed several unique features in DiPKS proteins. Our studies provide a new perspective in understanding mechanisms by which metabolic diversity could be generated by combining existing functional scaffolds. 相似文献
95.
Bacillus subtilis strain UK-9, an isolate from reclaimed soils, was studied for its biological control activity against Alternaria leaf spot disease of mustard. In dual culture, production of antifungal metabolites by the bacteria caused morphological alterations of vegetative cells and spores, disruption and lysis of their cell wall. The antagonist reduced spore germination on leaves and disease incidence of the pathogen in plant trial as well as it also demonstrated plant-growth-promoting ability. 相似文献
96.
A laboratory experiment was conducted to examine the potentiality of a natural resource neem (Azadirachta indica) seed kernel powder (NSKP) to reduce the urease and nitrification activities in different soils (viz., normal, acid, and sodic) at contrasting moisture (1:1 soil to water and field capacity) and temperature regimes (10 degrees C and 37 degrees C). Results have revealed that application of NSKP with urea did not exhibit any urease inhibitory property in normal and sodic soils, but in acid soil it had maintained higher concentration of urea than the urea alone treated samples for two weeks after application. At 37 degrees C and under field capacity moisture level, urea hydrolysis was more rapid than at 10 degrees C and under waterlogged (1:1) conditions. The NSKP has showed variable effects (4-28%) to inhibit nitrification during 7-21 days after application, depending upon the soil types, temperature and moisture regimes. The nitrification activity was significantly low in acid soil followed by normal and sodic soils. The present study suggests that NSKP has the potential to retard the urease activity in acid soil, and nitrification in all the soils, and thus it may be used along with urea for the better use of applied -N. 相似文献
97.
Three categories of compound yolks are synthesized during vitellogenesis of Mylabris pustulata. CY1 bodies originate de novo and are composed of protein-carbohydrate (glycogen)-RNA complex. CY2 bodies originate from precursors in follicular epithelium and are composed of protein-carbohydrate (glycogen) complex. CY3 bodies originate from extraovarian precursors and are composed of protein-acid mucopolysaccharide-glycogen-phospholipid complex. 相似文献
98.
Mayank Mittal Sanjay Kumar Biswas Vandana Singh Nidhi Arela Vishwa Mohan Katoch Ram Das Virendra Singh Yadav Bharat Bajaj Keshar Kunja Mohanty 《Molecular biology reports》2018,45(4):469-476
Tuberculosis (TB) is a disease of global importance. There is an increasing recognition of the role of Toll like receptors, important pattern recognition receptors of host immune system, in determining the susceptibility or resistance to TB in various populations. In an attempt to examine the importance of Toll like receptors in immune response to Mycobacterium tuberculosis infection, we explored two variants each of TLR2 and TLR9 in a population residing in Uttar Pradesh, India. Genotyping was performed to detect -196 to -174 del polymorphism and G2258A SNP (Arg753Gln, rs5743708) in TLR2 gene and -T1237C (rs5743836) and G2848A (rs352140) SNP in TLR9 gene in patients with pulmonary TB and healthy controls. The A allele of G2848A SNP in TLR9 gene was found with a marginally higher frequency among TB patients as compared to healthy controls, suggesting that A allele at position 2848 of TLR9 gene may be associated with susceptibility to TB in North Indian population [p?=?0.05, Mantel–Haenszel OR?=?1.34, 95% CI (1.0–1.82)]. 相似文献
99.
R. K. Raman S. K. Mohanty K. S. Bhatta S. K. Karna A. K. Sahoo B. P. Mohanty B. K. Das 《Wetlands Ecology and Management》2018,26(4):677-687
Chilika, a Ramsar site and the largest brackish water lagoon in Asia, is situated in East Coast of India, endowed with rich fisheries resources. In this study, SARIMAX fisheries forecasting model was developed by using seasonal ARIMA (Auto Regressive Integrated Moving Average) model with three external physicochemical factors (factor 1 was dominated by the combined effect of salinity and temperature and factor 2 and factor 3 were dominated by alkalinity and transparency) in Chilika. Monthly fish catch data and physico-chemical parameters of water from 2001–2002 to 2015–2016 was used to develop model. The results showed SARIMAX model; SARIMA (1,0,0)(2,0,0)12 with factor 1, factor 2 and factor 3 was the best fitted model for the fish catch in Chilika. The factor 1 was found to be positive influence on catch at 10% level of significance (p = 0.089) while, factor 2 and factor 3 were found to be insignificant. The developed SARIMAX model was validated with actual annual fish catch for the years 2011–2015 with prediction error 3–7%. Further, the developed SARIMAX model was used to forecast fish catch for the period April 2016 to March 2018 indicating increasing 10% present catch in the lagoon. The developed SARIMAX model in the present case study is of the first time to forecast and visualise the positive influence of salinity and temperature on the fish catch in the Chilika lagoon. 相似文献
100.
A dysmorphic male child of 8 months age presented with microphthalmia, micrognathia, hypertelorism, wide anterior fontanelles, large forehead, short neck, prominent ears, macrotestis and delayed developmental milestones. The patient presented with generalised seizures hydrocephalaus and Coarctation of aorta (Pre subclavian). He also had mild hypocalcaemia with normal renal function. Cytogenetic study revealed 18p(-) picture due to translocation between 14 p & 18q. Since the spectrum of clinical expression is similar to that is seen in 18p(-) syndrome it is suggested that not only whole of 18p but part of chromosome no. 18 proximal to 18 q 11.2 may also be involved in this phenotype. 相似文献