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151.
152.
The genome of Cucumber mosaic virus New Delhi strain (CMV-ND) from India, obtained from tomato, was completely sequenced and compared with full genome sequences of 14 known CMV strains from subgroups I and II, for their genetic diversity. Sequence analysis suggests CMV-ND shares maximum sequence identity at the nucleotide level with a CMV strain from Taiwan. Among all 15 strains of CMV, the encoded protein 2b is least conserved, whereas the coat protein (CP) is most conserved. Sequence identity values and phylogram results indicate that CMV-ND belongs to subgroup I. Based on the recombination detection program result, it appears that CMV is prone to recombination, and different RNA components of CMV-ND have evolved differently. Recombinational analysis of all 15 CMV strains detected maximum recombination breakpoints in RNA2; CP showed the least recombination sites. 相似文献
153.
Mohammad Yusuf Qazi Fariduddin Iqbal Ahmad Aqil Ahmad 《Physiology and Molecular Biology of Plants》2014,20(4):449-460
The role of 28-homobrassinolide (HBL) in countering nickel-induced oxidative damage through overexpression of antioxidant enzymes and proline in Vigna radiata has been investigated. Two varieties of V. radiata, one sensitive to Ni (PDM-139) and the other tolerant to Ni (T-44), were sown in the soil fed with different levels (0, 50, 100 or 150 mg kg−1) of Ni, and at 29-day stage, foliage of plants was applied with deionized water (control), 10−8 or 10−6 M of HBL. The plants were sampled at 45-day stage of growth to assess various physiological as well as biochemical characteristics. The remaining plants were allowed to grow up to maturity to study the yield characteristics. The growth traits, leghemoglobin, nitrogen and carbohydrate content in the nodules, leaf chlorophyll content, photosynthesis efficiency, leaf water potential, activities of nitrate reductase, carbonic anhydrase and nitrogenase decreased proportionately with the increasing concentrations of nickel, whereas electrolyte leakage, various antioxidant enzymes viz. catalase, peroxidase and superoxide dismutase and accumulation of proline increased at 45-day stage. However, the exogenously applied HBL to the nickel-stressed or non-stressed plants improved growth, nodulation and photosynthesis and further enhanced the various antioxidant enzymes viz. catalase, peroxidase and superoxide dismutase and accumulation of proline. The deleterious impact of Ni on the plants was concentration dependent where HBL applied to the foliage induced overexpression of antioxidant enzyme and accumulation of proline (osmolyte) which could have conferred tolerance to Ni up to 100 mg kg−1, resulting in improved growth, nodulation, photosynthesis and yield attributes. 相似文献
154.
Mohd Haneef Mohtashim Lohani Anupam Dhasmana Qazi M.S Jamal S.M.A Shahid Sumbul Firdaus 《Bioinformation》2014,10(8):526-532
Cell cycle is maintained almost all the times and is controlled by various regulatory proteins and their complexes (Cdk+Cyclin) in
different phases of interphase (G1, S and G2) and mitosis of cell cycle. A number of mechanisms have been proposed for the
initiation and progression of carcinogenesis by abruption in cell cycle process. One of the important features of
cancer/carcinogenesis is functional loss of these cell cycle regulatory proteins particularly in CDKs and cyclins. We hypothesize
that there is a direct involvement of these cell cycle regulatory proteins not only at the genetic level but also proteins level, during
the initiation of carcinogenesis. Therefore, it becomes significant to determine inconsistency in the functioning of regulatory
proteins due to interaction with carcinogen 4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK). Hence, we investigated the
interaction efficiency of NNK, against cell cycle regulatory proteins. We found a different value of ΔG (free energy of binding)
among the studied proteins ranging between -3.29 to -7.25 kcal/mol was observed. To validate the results, we considered Human
Oxy-Hemoglobin at 1.25 Å Resolution, [PDB_ID:1HHO] as a +ve control, (binding energy -6.06 kcal/mol). Finally, the CDK8
(PDB_ID:3RGF) and CDK2 (PDB_ID:3DDP) regulatory proteins showing significantly strong molecular interaction with NNK -7.25
kcal/mol, -6.19 kcal/mol respectively were analyzed in details. In this study we predicted that CDK8 protein fails to form functional
complex with its complementary partner cyclin C in presence of NNK. Consequently, inconsistency of functioning in regulatory
proteins might lead to the abruption in cell cycle progression; contribute to the loss of cell cycle control and subsequently
increasing the possibility of carcinogenesis. 相似文献
155.
S. M. Ahmed V. Verma P. H. Qazi M. M. Ganaie S. K. Bakshi G. N. Qazi 《Plant Systematics and Evolution》2005,256(1-4):75-87
The phylogenetic relationships among the three species of Tinospora found in India are poorly understood. Morphology does not fully help to resolve the phylogeny and therefore a fast approach
using molecular analysis was explored. Two molecular approaches viz Random Amplified Polymorphic DNA (RAPD) assay and restriction
digestion of ITS1-5.8S-ITS2 rDNA (PCR-RFLP) were used to evaluate the genetic similarities between 40 different accessions
belonging to three species. Of the 38 random primers used only six generated the polymorphism, while as three out of 11 restriction
enzymes used gave polymorphic restriction patterns. The average proportion of polymorphic markers across primers was 95%,
however restriction endonucleases showed 92% polymorphism. RAPD alone was found suitable for the species diversions. In contrast
PCR- RFLP showed bias in detecting exact species variation. The correlation between the two markers was performed by Jaccard's
coefficient of similarity. A significant (r= 0.574) but not very high correlation was obtained. Further to authenticate the
results obtained by two markers, sequence analysis of ITS region of ribosomal DNA (ITS1 and ITS2, including 5.8S rDNA) was
performed. Three independent clones of each species T. cordifolia, T. malabarica and T. crispa were sequenced. Phylogenetic relationship inferred from ITS sequences is in agreement with RAPD data. 相似文献
156.
The in-vitro bioassay for LH, using mouse Leydig cells, has been modified for the direct measurement of serum LH in the male rhesus monkey. Validation of the assay demonstrated good reliability in terms of accuracy, precision and sensitivity (1.5 mi.u./ml). Basal LH concentrations in laboratory-maintained monkeys with and without anaesthesia were not significantly different from those in free-ranging, feral monkeys. LH-RH (50 micrograms i.v.) elicited a 30-fold increase in LH concentrations after 30 min. LH levels in castrated adult monkeys were approximately 50 times the normal levels. Intact and castrated juvenile males had only very low LH levels. LH from the serum of an adult male castrate was further characterized by Sephadex G100 column chromatography. The in-vitro bioassay provides a preferable alternative to the heterologous radioimmunoassay method for the routine determination of LH in the rhesus monkey. 相似文献
157.
Frees D Chastanet A Qazi S Sørensen K Hill P Msadek T Ingmer H 《Molecular microbiology》2004,54(5):1445-1462
The Hsp100/Clp ATPases constitute a family of closely related proteins of which some members function solely as chaperones whereas others additionally can associate with the unrelated ClpP peptidase forming a Clp proteolytic complex. We have investigated the role of four Clp ATPases in the versatile pathogen, Staphylococcus aureus. Previously, we showed that ClpX is required for expression of major virulence factors and for virulence of S. aureus, but not for survival during heat shock. In the present study, we have inactivated clpC, clpB and clpL and, while none of these mutations affected toxin production, both ClpC and ClpB and to a minor extent ClpL were required for intracellular multiplication within bovine mammary epithelial cells. These defects were paralleled by an inability of the clpC mutant to grow at high temperature and of the clpB mutant to induce thermotolerance indicating that the protective functions of these proteins are required both at high temperature and during infection. By primer extension analysis and footprint studies, we show that expression of clpC and clpB is controlled by the negative heat-shock regulator, CtsR, and that ClpC is required for its repressor activity. Thus, ClpC is a likely sensor of stress encountered during both environmental stress and infection. In addition to virulence factor production the ability to form biofilms is of importance to S. aureus as a nosocomial pathogen. Interestingly, biofilm formation was reduced in the absence of ClpX or ClpC whereas it was enhanced in the absence of ClpP. Thus, our data show that Clp proteolytic complexes and the Clp ATPases control several key processes of importance to the success of S. aureus as a pathogen. 相似文献
158.
159.
160.
Fluid shear stress regulates the invasive potential of glioma cells via modulation of migratory activity and matrix metalloproteinase expression 总被引:1,自引:0,他引:1