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141.

An aquatic cash crop, ‘makhana’ (Euryale ferox Salisb.) was studied for predicted habitat suitability through ‘BioClim’ model for the year 1950–2000 and projected climate data for 2050 and 2070 for the Indian region based on primary data from survey and exploration for germplasm collection by ICAR-National Bureau of Plant Genetic Resources (ICAR-NBPGR), New Delhi, India. A total of 362 diverse ‘makhana’ or foxnut germplasm accessions were augmented mainly from different districts of Indian state of Bihar and conserved at the National Genebank (NGB) at ICAR-NBPGR, New Delhi. Predicted habitat suitability map of climate for the period 1950–2000 showed that the current locations of the highly suitable areas of cultivation of ‘makhana’ in Bihar were extended to other states namely- Jharkhand, Uttar Pradesh and West Bengal in eastern India. Out of the total highly suitable estimated areas, maximum were located in Bihar (65.0 per cent) followed by Uttar Pradesh (12.3 per cent), Jharkhand (12.2 per cent) and West Bengal (10.5 per cent). Based on future predicted climate data for the year 2050 the habitat suitability map indicated that out of the total high suitable areas, Bihar had maximum area as compared to the other three states. Predicted climate data using ‘BioClim’ variables showed that high suitable areas shifted from major part in Jharkhand, Uttar Pradesh and West Bengal and negligible areas bordering Katihar district of Bihar. While predicted climate data for the year 2050 and 2070 showed high suitable areas in West Bengal, especially Malda and Dakschin Dinajpur districts completely shrank due to temperature rise; while Uttar Dinajpur (Goal Pokhar-I, Goal Pokhar-II and Islampur districts) appeared as new areas. In Uttar Pradesh, new districts viz. Balrampur and Shravasti were identified as high suitable areas for ‘makhana’ cultivation. As ‘makhana’ is a popular cash crop of eastern part of the country, and has not been cultivated widely in other regions, hence the knowledge on its botany, distribution, cultivation practices and uses are provided.

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142.
Fourteen apricot genotypes grown under similar cultural practices in Trans-Himalayan Ladakh region were studied to find out the influence of genotype on antioxidant capacity and total phenolic content (TPC) of apricot kernel. The kernels were found to be rich in TPC ranging from 92.2 to 162.1 mg gallic acid equivalent/100 g. The free radical-scavenging activity in terms of inhibitory concentration (IC50) ranged from 43.8 to 123.4 mg/ml and ferric reducing antioxidant potential (FRAP) from 154.1 to 243.6 FeSO4.7H2O μg/ml. A variation of 1–1.7 fold in total phenolic content, 1–2.8 fold in IC50 by 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and 1–1.6 fold in ferric reducing antioxidant potential among the examined kernels underlines the important role played by genetic background for determining the phenolic content and antioxidant potential of apricot kernel. A positive significant correlation between TPC and FRAP (r = 0.671) was found. No significant correlation was found between TPC and IC50; FRAP and IC50; TPC and physical properties of kernel. Principal component analysis demonstrated that genotypic effect is more pronounced towards TPC and total antioxidant capacity (TAC) content in apricot kernel while the contribution of seed and kernel physical properties are not highly significant.  相似文献   
143.
This study has been conducted to determine the extent of genetic association between yield of Rice (Oryza sativa L.) and its components. The present experiment was carried out with 40 Rice (Oryza sativa L.) genotypes which were evaluated in a randomized block design with 3 replications during wet season of 2007 and 2008. Results showed that sufficient amount of variability was found in the entire gene pool for all traits studied. Higher magnitude of genotypic and phenotypic coefficients of variation was recorded for seed yield, harvest index, biological yield, number of spikelets per panicle, flag leaf length, plant height and number of tillers indicates that these characters are least influence by environment. High heritability coupled with high genetic advance as percent of mean was registered for seed yield, harvest index, number of spikelets per panicle, biological yield and flag leaf length, suggesting preponderance of additive gene action in the expression of these characters. Grain yield was significantly and positively associated with harvest index, number of tillers per hill, number of panicle per plant, panicle length, number of spikelet's per panicle and test weight at both genotypic and phenotypic levels. Path coefficient analysis revealed that harvest index, biological yield, number of tillers per hill, panicle length, number of spikelets per panicle, plant height and test weight had direct positive effect on seed yield, indicating these are the main contributors to yield. From this study it may be concluded that harvest index, number of tillers per hill, panicle length and number of spikelet per panicle and test weight are the most important characters that contributed directly to yield. Thus, these characters may serve selection criteria for improving genetic potential of rice.  相似文献   
144.
Background:Single nucleotide polymorphisms in OGG1 gene modulates DNA repair capacity and functions as one of the first lines of protective mechanisms against 8-OHdG mutagenicity. OGG1-Cys326 gene polymorphism may decrease DNA repair function, causing oxidative stress due to higher oxidative DNA damage. The main purpose of this study was to examine the link of oxidative and genotoxic DNA damage with DNA repair OGG1 gene polymorphism, in charcoal workers exposed to polyaromatic hydrocarbons. Methods:Urinary 8-OHdG excretion (a biomarker of oxidative DNA damage) was determined in both exposed and control populations. Genotyping of OGG1 DNA repair gene in the blood samples of subjects was carried out by PCR-RFLP method. Results:The 8-OHdG urinary concentration was significantly higher (p < 0.05) in the exposed (geometric mean 12.33 ± 3.78) than in the unexposed (geometric mean 7.36 ± 2.29) population. DNA damage, as measured by 8-OHdG and TM content, was found to be significantly higher in OGG1 homozygous mutants (mt/mt; 18.81 ± 3.34; 6.04 ± 0.52) as compared to wild-type genotypes (wt/wt; 10.34 ± 2.25; 5.19 ± 2.50) and heterozygous (wt/mt) mutants (12.82 ± 2.81; 6.04 ± 0.93) in the exposed group. Conclusion:We found a significant association of OGG1 heterozygous (wt/mt) and homozygous (mt/mt) variants with oxidative and genotoxic damage, suggesting that these polymorphisms may modulate the effects of PAH exposure in occupational workers. Key Words: 8-hydroxy-2’-deoxyguanosine, 1-hydroxypyrene, Polycyclic aromatic hydrocarbons  相似文献   
145.
Summary

Abelmoschus is regarded as a polyploid-polyspecies complex and a genus with variable genome organisation and resultant ambiguity in its speciation. A cytogenetic basis for taxonomy can be significant, due to the fact that many of the taxonomic units of Abelmoschus are heterogeneous in nature with deviant numbers of chromosomes. In the present investigation, 39 wild and cultivated accessions of Abelmoschus from India, belonging to three representative taxa, were used to record clear and authentic chromosome counts. From these data, the numbers of somatic chromosomes in A. angulosus var. grandiflorus, A. moschatus ssp. moschatus, and A. moschatus ssp. tuberosus are reported to be 2n = 66, 2n = 72, and 2n = 72, respectively. The present study also confirmed 2n = 130 to be the authentic number of somatic chromosomes in A. esculentus. Earlier conflicting reports are ruled out. Reports of the occurrence of cytotypes in A. esculentus are not acceptable, due to its wide area of cultivation.  相似文献   
146.
The present study was carried out to study the effect of different doses of hemp seed alone or in combination with dill seed against antibiotic growth promoter on performance, serum biochemicals and gut health of broiler chickens over a period of 42 days. Total 192 broiler chicks were grouped randomly into six treatments and fed with basal diet (BD) along with different levels of seeds, viz., T1 (BD), T2 (BD + 0.2% HS), T3 (BD + 0.2% HS + 0.3 DS), T4 (BD + 0.3% HS) and T5 (BD + 0.3% HS + 0.3 DS) and T6 (BD + 0.025% Bacitracin Methylene Disalicylate‐BMD). The performance traits like feed intake, body weight gain and feed conversion ratio (FCR) and carcass traits like cut‐up parts, giblet and abdominal fat yield remained unaffected due to dietary treatments for overall trial period; however, the average feed intake in early phase (0–3 weeks) reduced significantly (p < 0.05) in treatment birds than both controls (T1 & T6). Serum protein concentration remained unchanged, whereas significant (p < 0.05) reduction in serum lipids like triglyceride, LDL and total cholesterol concentration was noticed due to dietary inclusion of seeds. Serum enzymes like AST and ALT concentrations depleted significantly (p < 0.05) treated groups, except at higher seed doses (T5); however, alkaline phosphatase levels were unaffected. Coliform count in caecum and jejunum reduced linearly (p < 0.01) due to seed inclusion, whereas dose‐dependent proliferation of lactobacilli was evident (p < 0.01) in caecum and jejunum of treated birds. No effect was observed on the villus height and crypt depth of the jejunal mucosa. To conclude, dietary supplementation of hemp and dill seed could not affect the growth performance and carcass traits; however, it positively altered the serum lipid profile of the birds and improved gut health as well, thereby enhanced overall performance of broiler chickens.  相似文献   
147.
In this study, peste des petits ruminants virus (PPRV) was detected in frozen pooled tissue samples from a dead Asiatic lion (Panthera leo persica). The samples were negative for canine distemper virus and positive for PPRV nucleic acids when tested with one-step RT-PCR using the appropriate virus-specific primers. Subsequent amplification, cloning, and sequencing of the partial nucleocapsid, matrix, and fusion genes confirmed the presence of PPRV nucleic acid. Comparative sequence and phylogenetic analyses of the structural genes of the isolated virus confirmed that the virus belonged to Asian lineage IV and was closely related to PPRV circulating in India.  相似文献   
148.
Changes in residue management and incorporation of organic manures may help in carbon sequestration, restoring soil organic carbon (SOC) and sustaining the productivity of land under a cropping system. An experiment of multi-ratooning sugarcane (Saccharum officinarum L.) was initiated in 2003 in Inceptisols of Indian subtropics, to assess the effect of different organic manures and chemical fertilizer, on the crop productivity and soil quality. The annual sugarcane shoot biomass production in organic manure treatments was at par with the chemically fertilized treatment. Gross input of carbon (GIC) by the sugarcane crop was estimated to be 11.7–12.4 t ha−1 y−1 in different organic manure treatments compared to 8.4 and 5.0 t ha−1 y−1 in NPK and control treatments, respectively. The respiratory loss of C (RLC) increased linearly with increasing input of C in soil and it ranged from 3.3 to 4.1 t ha−1 y−1 in different treatments with maximum in FYM and minimum in control treatment. The sugarcane biomass added in the soil humified at a rate constant of 0.38 in sub-tropical conditions and an addition of 3.9 t C ha−1 y−1 is required to maintain SOC in equilibrium. After 5 years of sugarcane cropping (one plant + four ratoons) an increase of 2.3–17.1 t ha−1 in SOC over initial content was recorded with different treatments. Results in coming years from this long-term experiment shall add to the present calculated relationships between carbon addition and storage in sugarcane multi-ratooning crop production system under sub-tropical condition of India.  相似文献   
149.
Rice planthoppers' damage on Pusa Basmati 1 cultivar was simulated with InfoCrop, a generic crop growth simulation model. The model was calibrated and validated with two experimental data sets on planthopper population and rice yield that were generated through differential insecticide application during the rainy season 2006 and 2007. Simulated yield and total dry matter (TDM) in various treatments over the two experiments were found to be proximal to the observed yields (R2 = 0.972, RMSE = 4.61%) and TDM (R2 = 0.949, RMSE = 3.25%), respectively. Likewise, the simulated yield and TDM losses were also respectively close to observed yield losses (R2 = 0.938, RMSE = 13.53%) and TDM losses (R2 = 0.835, RMSE = 19.12%), suggesting appropriate validation of planthopper damage mechanism on Pusa Basmati 1 rice. Economic injury levels (EILs) of planthoppers were simulated with two control expenditures involving two applications with each of monocrotophos and imidacloprid, and three market prices of Pusa Basamti 1 rice. The EIL exhibited a negative relationship with market value of produce but a positive one with expenditure on control measures. Simulated EILs were comparable to earlier established empirical EILs, indicating utility of simulation models for developing location specific EILs that may help in doing away with the use of blanket EILs. Iso-loss curves, devised through validated model, depicted combinations of crop age and planthopper population that resulted in similar yield losses. Both the EILs and iso-loss curves can be useful in monitoring planthopper populations and promoting judicious pesticide applications that would avoid unwarranted control expenditure and environmental contamination. The simulation models being based on detailed crop ecological and physiological processes and pest damage mechanism can thus aid in development of location-specific decision support tools and ensure precision in pest management decisions.  相似文献   
150.
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