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1.
Effect of season, media type, carbon source, growth regulators and transplanting media on micropropagation of Dendrocalamus asper, an important bamboo species, was examined. The season of explant collection played an important role in axillary bud sprouting and spring (February?CApril) was found to be the best period for explant collection. Among the different media MS was found to be the best for micropropagation. Maximum numbers (4.83/explant) of shoots were initiated in MS?+?15???M BAP. For shoot multiplication, MS medium supplemented with 10???M BAP and 75???M Adenine sulfate was used. BAP was superior to KIN for both explant establishment, as well as, shoot multiplication. Optimal rooting was achieved in shoots cultured on ? strength MS medium supplemented with 5???M each of IBA and NAA. Regenerated plantlets were acclimatized and hardened in green house using dune sand and vermi-compost (3:1) with 92.34% success and transferred to the field with 100% survival rate. In the field, plants supplied with FYM along with urea showed better growth and development. Macroproliferation, plant multiplication by separating the rooted tillers of well established in vitro raised plantlets after 5 to 6?months of growth in the green house could double the multiplication rate. More than 25000 in vitro raised plants were successfully transferred to the field and no morphological variations in growth were observed, thus proving the potential of tissue culture for raising large scale plantations of D. asper.  相似文献   
2.
One-electron reduction of chromate by NADPH-dependent glutathione reductase   总被引:2,自引:0,他引:2  
Electron spin resonance (ESR) measurements provide evidence for the formation of Cr(V) intermediates in the enzymatic reduction of Cr(VI) by glutathione reductase (GSSG-R) in the presence of NADPH, indicating an initial single-electron transfer step in the reduction mechanism. Depending on the pH, at least two different Cr(V) species are generated which are relatively long-lived. In addition, we have detected the hydroxyl (.OH) radical formation during the GSSG-R catalyzed reduction of Cr(VI) by spin trapping, employing 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) and alpha-(4-pyridyl-1-oxide)-N-tert-butylnitrone (4-POBN) as spin traps. Superoxide dismutase (SOD) causes only a minor effect on the .OH radical and Cr(V) formation, indicating that the O2- is not significantly involved in the reaction mechanism. Catalase enhances the Cr(V) formation and substantially inhibits the .OH radical formation, indicating the involvement of hydrogen peroxide (H2O2) in the reaction mechanism. Addition of H2O2 suppresses Cr(V) and enhances the .OH radical formation. Measurements involving N-ethylmaleimide show that the Cr(V) species, produced enzymatically by the reduction of Cr(VI) by GSSG-R, react with H2O2 to generate .OH radicals, which might participate in the initiation of Cr(VI) carcinogenicity.  相似文献   
3.
Fecundity of four species of catfishes, namely, Mystus seenghala (Sykes), Mystus cavasius (Ham), Wallagonia attu (Bloch) and Heteropneustes fossilis (Bloch), was studied. The fecundity of Mystus seenghala and Mystus cavasius varied between 20064 to 46443 and 3314 to 63135 respectively. In Wallagonia attu and Heteropneustes fossilis it varied between 66070 to 453148 and 1375 to 46737 respectively. In all the four species fecundity has a linear relationship with body weight and gonad weight, and a parabolic relationship with length in all the fishes excepting Mystus seenghala, where it is linear. By subjecting the data to multiple regression analysis, it is observed that the fecundity of each species can be most accurately determined by taking two variables together. In all the fishes studied the relative fecundity (Egg/body wt.) does not change significantly either with length or body weight.  相似文献   
4.
R. C. Dalal 《Plant and Soil》1982,66(2):265-269
Summary The phosphatase activity of the soil amended with roots and tops of clover (Trifolium repens) plant material (0.1% by weight) remained essentially constant in the absence of growing plants but changed considerably in the presence of plants (Avena sativa) grown for 10 weeks. There was a significant relationship between the phosphatase activity and organic and inorganic P in the soil solution only in the presence of growing plants. The differences in phosphatase activity between roots and tops amended soil were attributed to total C as well as differences in the degree of availability of C added through plant materials. This may also apply to the carpet grass (Axonopus affinis) amended soil.  相似文献   
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6.
The antibacterial and anti-biofilm activities of propolis have been intensively reported. However, the application of this folk remedy as a means to prevent biomedical implant contamination has yet to be completely evaluated. In response to the significant resistant and infectious attributes of biofilms, biomaterials engineered to possess specific chemical and physical properties were immobilized with metal free Russian propolis ethanol extracts (MFRPEE), a known antibacterial agent. The results obtained from this study begin to examine the application of MFRPEE as a novel alternative method for the prevention of medical and biomedical implant infections. When constructed under specific experimental conditions, immobilized biomaterials showed excellent stability when subjected to simulated body fluid and fetal bovine serum. The ability of immobilized biomaterials to specifically target pathogens (both Gram-positive and Gram-negative biofilm forming bacteria), while promoting tissue cell growth, renders these biomaterials as potential candidates for clinical applications.  相似文献   
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8.
Sorghum with its remarkable adaptability to drought and high temperature provides a model system for grass genomics and resource for gene discovery especially for abiotic stress tolerance. Group 3 LEA genes from barley and rice have been shown to play crucial role in abiotic stress tolerance. Here, we present a genome-wide analysis of LEA3 genes in sorghum. We identified four genes encoding LEA3 proteins in the sorghum genome and further classified them into LEA3A and LEA3B subgroups based on the conservation of LEA3 specific motifs. Further, expression pattern of these genes were analyzed in seeds during development and vegetative tissues under abiotic stresses. SbLEA3A group genes showed expression at early stage of seed development and increased significantly at maturity, while SbLEA3B group genes expressed only in matured seeds. Expression of SbLEA3 genes in response to abiotic stresses such as soil moisture deficit (drought), osmotic, salt, and temperature stresses, and exogenous ABA treatments was also studied in the leaves of 2-weeks-old seedlings. ABA and drought induced the expression of all LEA3 genes, while cold and heat stress induced none of them. Promoter analysis revealed the presence of multiple ABRE core cis-elements and a few low temperature response (LTRE)/drought responsive (DRE) cis-elements. This study suggests non-redundant function of LEA3 genes in seed development and stress tolerance in sorghum.  相似文献   
9.
The PE and PPE protein family are unique to mycobacteria. Though the complete genome sequences for over 500 M. tuberculosis strains and mycobacterial species are available, few PE and PPE proteins have been structurally and functionally characterized. We have therefore used bioinformatics tools to characterize the structure and function of these proteins. We selected representative members of the PE and PPE protein family by phylogeny analysis and using structure-based sequence annotation identified ten well-characterized protein domains of known function. Some of these domains were observed to be common to all mycobacterial species and some were species specific.  相似文献   
10.
Molecular Biology Reports - On the background of the epidemiological link between diabetes and oral cancer, the present study aimed to analyze the potential involvement of selected glucose...  相似文献   
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