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211.
212.
Thorium-232 (232Th), a natural radionuclide from the actinide family, is abundantly present in monazite and other ores. It is used as one of the prime fuel materials in nuclear industry and may pose an exposure risk to nuclear workers and members of the public. Human erythrocytes, as a classical cellular membrane model, were coincubated with 232Th in order to elucidate whether this naturally occurring important radionuclide produced perturbations to cell membrane. Present study revealed that erythrocytes underwent aggregation or lysis depending on the ratio of 232Th to cell. Scanning electron micrographs showed that erythrocytes transformed into equinocytes and/or spherocytes after 232Th treatment. Further examination of erythrocyte by atomic force microscopy suggested significant increase in surface roughness after 232Th treatment. Experiments on neuraminidase treated and/or anti-GpA antibody blocked erythrocytes suggested significant role of membrane sialic acid and glycophorin A (GpA) protein in aggregation or hemolytic effects of 232Th. Further results showed that 232Th caused hemolysis by colloid osmotic mechanism, as evidenced by potassium efflux, osmotic protection and osmotic fragility studies. Osmoprotection experiments indicated that hemolysis get elicited through the formation of membrane pores of ∼2.0 nm in size. Hemolysis studies in presence of inhibitors (TEA, bumetanide, DIDS and amiloride) revealed the role of K+ channel, Na+/K+/2Cl− channel, Cl−/HCO3− anion exchanger and Na+/H+ antiporter in 232Th induced erythrolysis. Presence of non-diffusible cation (N-methyl d-glucasamine) or anion (gluconate) in erythrocyte suspending medium further confirm the role of Na+ and Cl− influx in hemolytic effect of 232Th. These findings provide significant insight in structural, biochemical and osmotic toxic effects of 232Th on human erythrocytes. 相似文献
213.
Entry of bovine viral diarrhea virus into ovine cells occurs through clathrin-dependent endocytosis and low pH-dependent fusion 总被引:1,自引:0,他引:1
Basavaraj Shrishail Mathapati Niranjan Mishra Katherukamem Rajukumar Ram Kumar Nema Sthita Pragnya Behera Shiv Chandra Dubey 《In vitro cellular & developmental biology. Animal》2010,46(5):403-407
Although mechanisms of bovine viral diarrhea virus (BVDV) entry into bovine cells have been elucidated, little is known concerning
pestivirus entry and receptor usage in ovine cells. In this study, we determined the entry mechanisms of BVDV-1 and BVDV-2
in sheep fetal thymus cells. Both BVDV-1 and BVDV-2 infections were inhibited completely by chlorpromazine, β-methyl cyclodextrin,
sucrose, bafilomycin A1, chloroquine, and ammonium chloride. Simultaneous presence of reducing agent and low pH resulted in
marked loss of BVDV infectivity. Moreover, BVDV was unable to fuse with ovine cell membrane by the presence of reducing agent
or low pH alone, while combination of both led to fusion at low efficiency. Furthermore, sheep fetal thymus cells acutely
infected with BVDV-1 or BVDV-2 were found protected from heterologous BVDV infection. Taken together, our results showed for
the first time that entry of both BVDV-1 and BVDV-2 into ovine cells occurred through clathrin-dependent endocytosis, endosomal
acidification, and low pH-dependent fusion following an activation step, besides suggesting the involvement of a common ovine
cellular receptor during attachment and entry. 相似文献
214.
Four different bacterial strains were isolated from pulp and paper mill sludge in which one alkalotolerant isolate (LP1) having
higher capability to remove color and lignin, was identified as Bacillus sp. by 16S RNA sequencing. Optimization of process parameters for decolorization was initially performed to select growth
factors which were further substantiated by Taguchi approach in which seven factors, % carbon, % black liquor, duration, pH,
temperature, stirring and inoculum size, at two levels, applying L-8 orthogonal array were taken. Maximum color was removed
at pH 8, temperature 35°C, stirring 200 rpm, sucrose (2.5%), 48 h, 5% (w/v) inoculum size and 10% black liquor. After optimization
2-fold increase in color and lignin removal from 25–69% and 28–53%, respectively, indicated significance of Taguchi approach
in decolorization and delignification of lignin in pulp and paper mill effluent. Enzymes involved in the process of decolorization
of effluent were found to be xylanase (54 U/ml) and manganese peroxidase (28 U/ml). Treated effluent was also evaluated for
toxicity by Comet assay using Saccharomyces cerevisiae MTCC 36 as model organism, which indicated 58% reduction after treatment by bacterium. 相似文献
215.
Biswajit Mishra Vipul Kumar Srivastava Rama Chaudhry Rishi Kumar Somvanshi Abhay Kumar Singh Kamaldeep Gill Ramesh Somvanshi Ishan Kumar Patro Sharmistha Dey 《Amino acids》2010,39(5):1493-1505
Anti-bacterial drug resistance is one of the most critical concerns among the scientist worldwide. The novel antimicrobial
decapeptide SD-8 is designed and its minimal inhibitory concentration and therapeutic index (TI) was found in the range of
1–8 μg/ml and 45–360, respectively, against major group of Gram positive pathogens (GPP). The peptide was also found to be
least hemolytic at a concentration of 180 μg/ml, i.e., nearly 77 times higher than its average effective concentration. The
kinetics assay showed that the killing time is 120 min for methicillin-sensitive Staphylococcus aureus (MSSA) and 90 min for methicillin-resistant S. aureus (MRSA). Membrane permeabilization is the cause of peptide antimicrobial activity as shown by the transmission electron microscopy
studies. The peptide showed the anti-inflammatory property by inhibiting COX-2 with a K
D and K
i values of 2.36 × 10−9 and 4.8 × 10−8 M, respectively. The peptide was also found to be effective in vivo as derived from histopathological observations in a Staphylococcal
skin infection rat model with MRSA as causative organism. 相似文献
216.
Upadhyay SK Mishra M Singh H Ranjan A Chandrashekar K Verma PC Singh PK Tuli R 《Proteomics》2010,10(24):4431-4440
Allium sativum leaf agglutinin (ASAL) binds to several proteins in the midgut of Helicoverpa armigera and causes toxicity. Most of these were glycosylated. Six ASAL-binding proteins were selected for identification. PMF and MS/MS data showed their similarity with midgut aminopeptidase APN2, polycalins and alkaline phosphatase of H. armigera, cadherin-N protein (partial AGAP009726-PA) of Acyrthosiphon pisum, cytochrome P450 (CYP315A1) of Manduca sexta and alkaline phosphatase of Heliothis virescens. Some of the ASAL-binding midgut proteins were similar to the larval receptors responsible for the binding of δ-endotoxin proteins of Bacillus thuringiensis. Galanthus nivalis agglutinin also interacted with most of the ASAL-binding proteins. The ASAL showed resistance to midgut proteases and was detected in the larval hemolymph and excreta. Immunohistochemical staining revealed the presence of ASAL in the body tissue also. 相似文献
217.
Bandamaravuri Kishore Babu S. S. Reddy Mukesh K. Yadav M. Sukumar Vijendra Mishra A. K. Saxena Dilip K. Arora 《Indian journal of microbiology》2010,50(2):199-204
Genetic diversity analysis of Macrophomina phaseolina isolates obtained from different host range and diverse geographical locations in India was carried out using RAPD fingerprinting.
Of the thirteen 10-mer random primers used, primer OPB-08 gave the maximum polymorphism and the UPGMA clustering could separate
50 isolates in to ten groups at more than 65% similarity level. The ten clusters correlated well with the geographical locations
with exceptions for isolates obtained from Eastern and Western Ghats. There was a segregation of isolates from these two geographical
locations in to two clusters thus, distributing 10 genotypes in to eight geographical locations. All the isolates M. phaseolina irrespective of their host and geographical origin, exhibited two representative monomorphic bands at 250 bp and 1 kb, presence
of these bands suggests that isolates might have evolved from a common ancestor but due to geographical isolation fallowed
by natural selection and genetic drift might have segregated in to subpopulations. Genetic similarity in the pathogenic population
reflects the dispersal of single lineage in all locations in India. 相似文献
218.
Natwar Singh Avinash Mishra Mukul Joshi Bhavanath Jha 《Plant Cell, Tissue and Organ Culture》2010,103(1):1-6
Pre-cultured cumin embryos were bombarded under 27 inches Hg vacuum, 25 mm distance from rupture disc to macrocarrier, 10 mm
macrocarrier flight distance using 1100 psi rupture disc and 9 cm microprojectile travel distance. An average of 110 embryos
was used per shot and 91% embryos showed transient GUS expression after 24 h. Shoot tips and roots of T0 plantlets exhibited GUS expression done after 3 months of bombardment. Transformation was confirmed with PCR amplification
of 0.96 and 1.3 kb band of hptII and gus genes respectively from T0 transgenics and southern blot analysis using PCR amplified DIG labeled hptII gene as probe. It is the first successful attempt of transformation of cumin plant through direct gene transfer using particle
gene gun and adequately exhibiting the possibility of stable transformation in cumin. 相似文献
219.
R. Arora S. Bhatia B. P. Mishra R. Sharma A. K. Pandey B. Prakash A. Jain 《Biochemical genetics》2010,48(3-4):304-311
The genetic polymorphism of the β-lactoglobulin (β-LG) gene was determined in 638 animals belonging to 15 native Indian sheep breeds reared in different agroecological regions for various production traits. Variants of β-LG were found using PCR–RFLP of genomic DNA. Rsa1 restriction enzyme digestion of a 120-bp PCR fragment of exon 2 of β-LG revealed two genetic variants, A (0.37) and B (0.63), and the three genotypes AA (0.175), AB (0.389), and BB (0.436). The differences in allelic frequency were not significant across the breeds, irrespective of their geographic origin and utility (χ2 test, P > 0.05). The pattern of occurrence of allelic variants revealed that the B allele was more frequent in the majority of the Indian breeds than in breeds reported from countries of Southwest Asia, Eastern and Central Europe, and the Mediterranean. A higher level of heterozygosity (0.422) was discerned, despite the declining status of several of the Indian breeds. These findings revealed that Indian sheep are predominantly of the β-LG B type. 相似文献
220.
Rajeev K. Singh Kuldeep K. Lal Vindhya Mohindra Peyush Punia Rama S. Sah Akhilesh K. Mishra Rajesh Kumar B. N. Mishra W. S. Lakra 《Biochemical genetics》2010,48(9-10):760-778
The population structure of Labeo calbasu from 11 rivers belonging to the Indus, Ganges, Bhima, Mahanadi, and Godavari basins was investigated using allozyme marker systems. Seven out of 20 allozyme loci (35%) were polymorphic (P < 0.99). Both probability and score tests indicated significant deviation of genotype proportions from Hardy–Weinberg expectations at two loci, XDH* (Mahanadi, Bhima, and Godavari) and G6PDH* (Mahanadi). A pairwise genetic homogeneity test and F ST values indicated a low-to-moderate level (0.0515) of genetic structuring in the wild population of L. calbasu. AMOVA analysis also indicated moderate differentiation among the samples from different river basins. Analysis for genetic bottleneck was performed under the infinite allele model. The study revealed nine genetic stocks of L. calbasu from the natural population across Indian rivers. Evidence of genetic bottlenecks in some rivers was also revealed. 相似文献