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Different concentrations of ammonium molybdate (10(-7) to 10(-4)M) affected the levels of metabolites in the source and sink organs of the seedlings of C. melo and C. vulgaris and data were recorded at 7, 14 and 21 days after treatment (DAT) of molybdenum (Mo). Reducing and non reducing sugars declined with an increase in concentration of ammonium molybdate from 10(-7) to 10(-4) M. Soluble protein and dry weight of seedlings increased in source at lower concentration (10(-7) M) and gradually decreased in all other concentrations (10(-6), 10(-5) and 10(-4) M). Starch was slightly accumulated in hypocotyl and fresh weight constantly declined with an increase in ammonium molybdate concentration from 10(-7) to 10(-4) M in all the parts of seedlings viz. cotyledon, hypocotyl and roots. Thus molybdenum at higher concentration induced decline in the metabolite levels in source and sink as well as in transporting organs.  相似文献   
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Grass pollen-induced hay-fever and allergic asthma represent a major health problem in industrialized countries. Whereas the symptoms of these allergic conditions can be controlled by pharmacotherapy, specific immunotherapy vaccination is the only causative approach towards the treatment of these type 1 allergies. Specific immunotherapy is based on administration of increasing amounts of the disease-causing allergens in the form of allergen-containing extracts. However, the extracts used for immunotherapy consist of allergenic and non-allergenic components and may induce severe anaphylactic side-effects upon therapeutic administration. With recent developments in molecular biology of pollen allergens it has become feasible to produce modified hypoallergenic derivatives of recombinant allergens with abrogated or greatly reduced likelihood of anaphylactic side-effects as compared to extract-based treatments. We have demonstrated this concept through reducing the anaphylactic potential of major rye grass pollen allergens by introducing a few point mutations which leave the overall structural fold of the molecule unaltered. These modified forms are expected to make allergen-specific immunotherapy more widely used in the future.  相似文献   
105.
Nucleotide excision repair (NER), a highly versatile DNA repair mechanism, is capable of removing various types of DNA damage including those induced by UV radiation and chemical mutagens. NER has been well characterized in yeast and mammalian systems but its presence in plants has not been reported. Here it is reported that a plant gene isolated from male germline cells of lily (Lilium longiflorum) shows a striking amino acid sequence similarity to the DNA excision repair proteins human ERCC1 and yeast RAD10. Homologous genes are also shown to be present in a number of taxonomically diverse plant genera tested, suggesting that this gene may have a conserved function in plants. The protein encoded by this gene is able to correct significantly the sensitivity to the cross-linking agent mitomycin C in ERCC1-deficient Chinese hamster ovary (CHO) cells. These findings suggest that the NER mechanism is conserved in yeast, animals and higher plants.  相似文献   
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Background

Cultures of human proximal tubule cells have been widely utilized to study the role of EMT in renal disease. The goal of this study was to define the role of growth media composition on classic EMT responses, define the expression of E- and N-cadherin, and define the functional epitope of MT-3 that mediates MET in HK-2 cells.

Methods

Immunohistochemistry, microdissection, real-time PCR, western blotting, and ELISA were used to define the expression of E- and N-cadherin mRNA and protein in HK-2 and HPT cell cultures. Site-directed mutagenesis, stable transfection, measurement of transepithelial resistance and dome formation were used to define the unique amino acid sequence of MT-3 associated with MET in HK-2 cells.

Results

It was shown that both E- and N-cadherin mRNA and protein are expressed in the human renal proximal tubule. It was shown, based on the pattern of cadherin expression, connexin expression, vectorial active transport, and transepithelial resistance, that the HK-2 cell line has already undergone many of the early features associated with EMT. It was shown that the unique, six amino acid, C-terminal sequence of MT-3 is required for MT-3 to induce MET in HK-2 cells.

Conclusions

The results show that the HK-2 cell line can be an effective model to study later stages in the conversion of the renal epithelial cell to a mesenchymal cell. The HK-2 cell line, transfected with MT-3, may be an effective model to study the process of MET. The study implicates the unique C-terminal sequence of MT-3 in the conversion of HK-2 cells to display an enhanced epithelial phenotype.  相似文献   
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Summary The present study is an attempt to exploit somaclonal variation for the varietal improvement of pigeonpea [Cajanus cajan (L) Millsp.]. The pigeonpea plants were regenerated from cotyledon explants, and their progeny was screened for variability. The regenerated R1 plants exhibited a spectrum of alterations in floral morphology and architecture that were absent in the control population. The field-sown R2 plants segregated for traits such as flower color, leaf shape, seed size, color and strophiolation, flowering habit, and fertility. Tissue culture produced different mutational events resulting in both dominant and recessive alleles. Significant variation was observed for plant height, seed mass, and damage due to the insect pest Helicoverpa armigera. The R3 plants, obtained from seed of R2 generation selected for traits such as white seed coat, strophiolation, reduced plant height, seed mass and low damage due to Helicoverpa, maintained the traits when compared with the seed-derived control populations. The results indicate a definite gene for white seed coat and the possibility of additional genes for pest tolerance and high seed mass in an adapted background. Submitted as Journal Article No. 1906 by International Crops Research Institute for the Semi-Arid Tropics (ICRISAT).  相似文献   
109.
The present study examines the secular trends in prevalence of overweight and obesity among urban Asian Indian adolescents in New Delhi (North India). The data were derived from cross-sectional sampling of children, 3493 in year 2006 and 4908 in year 2009, aged 14-17 years studying in privately-funded and government-funded schools. Age, gender and Asian Indian-specific cut offs of body mass index (BMI) were used to define overweight and obesity. The prevalence of obesity increased significantly from 9.8% in 2006 to 11.7% in 2009 (p<0.01), whereas underweight decreased from 11.3% to 3.9% (p<0.001). There was a significantly higher risk of being overweight (OR 1.28; 95% CI, 1.15-1.42) and obese (OR 1.44; 95% CI, 1.24-1.66) in year 2009 than 2006, after adjusting for age, gender and type of school. Males and privately-funded school children had significantly higher increase in prevalence and risk of being overweight and obese over the three years. In conclusion, this study showed an increasing trend in prevalence of overweight and obesity in urban Asian Indian adolescents. More specifically, the study showed the association of this increasing trend of overweight and obesity prevalence with male gender and high socio-economic status, calling for an urgent need for immediate and targeted preventive measures.  相似文献   
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