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281.
Kisspeptins, a family of neuropeptide encoded by the Kiss1 gene, have emerged as crucial regulator of fertility and reproduction by regulating the hypothalamic–pituitary–gonadal axis. The present study was aimed to identify and associate SNPs in the KISS1 gene with reproductive traits in cattle of Indian origin. DNA samples collected from 300 individual cows of three Indian dairy breeds (Gir, Kankrej and Frieswal) of cattle were used in the study. The SNPs of KISS1 gene were identified with PCR-RFLP and sequence analysis using two sets of primer pairs. A total of 5 SNPs were identified in the targeted region of which, two were selected for screening the population and association studies. The analysis revealed that genotypes of rs442633552G>A and rs42022871C>T had a significant association with dry period. The SNP rs42022871C>T also established significant role in milk production traits, and selection of TT-genotyped animals will improve the reproduction and production potential of the animals.  相似文献   
282.
Development of phosphate (P)-deficiency tolerant rice cultivars is constrained by lack of suitable, reproducible, and consistent seedling stage screening methods in breeding programs. This study reports the screening and characterization of M5 mutants derived from an ethyl methane sulfonate treated population of rice cv. Nagina 22 (N22) in low-P field (soil Olsen P 1.94–2.01 mg kg?1; alkaline Vertisol; pH 7.94) for high yield. The present study showed that seedling growth responses such as increase in root weight, root length, root/shoot weight, and dry weight in P-deficient medium can be taken as indices of low-P tolerance in mature plants in field. Total phosphorus content in seedlings showed an inverse relationship with total phosphorus content and low-P tolerance in mature plants in the field. But, phosphorus content in seeds and acid phosphatase activity in the seedling stage were positively correlated with survival and seed set in low-P field. In low-P field, plant height correlated most with yield per plant, and the number of productive tillers in mature plants was highly correlated with tiller number at vegetative stage. These mutants (NH776, NH710, and NH719) have agronomic importance because of their ability to grow and give higher yield than N22 in P-deficient field.  相似文献   
283.
Intergeneric hybridizations were produced between Elachanthemum intricatum (Franch.) Ling et Ling and Opisthopappus taihangensis (Y. Ling) C. Shih without emasculation. About 12 and 16 % seed settings were obtained in reciprocal hybridizations. 17 seedlings germinated from 183 seeds from Elachanthemum intricatum (Franch.) Ling et Ling as female parent and 13 seedlings germinated from 109 seeds of Opisthopappus taihangensis (Y. Ling) C. Shih as female parent. 14 and 8 plants survived to maturity respectively. Only one progeny from Elachanthemum intricatum (Franch.) Ling et Ling in these hybridizations was found to be a true hybrid from the morphological characteristics and sequences of nrDNA ITS. The leaves of this new hybrid show some conspicuous intermediate features. The new hybrid has 5–8 mini ray female florets in the outer row of capitula. It is perennial just like its paternal parent (Opisthopappus) in contrast to its biennial maternal parent (Elachanthemum).  相似文献   
284.
Many tropical forage grasses and legumes grow well in acid soils, adapting to excess aluminum (Al) and phosphorus (P) starvation stresses by using mechanisms that are still unclear. To determine these mechanisms, responses to Al toxicity and P starvation in three tropical forages were studied: two grasses, Brachiaria hybrid cv. ‘Mulato’ (B. ruziziensis clone 44-06 × B. brizantha cv. ‘Marandú’) and Andropogon gayanus, and one legume, Arachis pintoi. The tropical grasses tolerated high levels of Al toxicity and P starvation, with the Brachiaria hybrid maintaining very low levels of Al concentration in shoots. 27Al Nuclear Magnetic Resonance spectroscopy (NMR) analysis revealed that, in the Brachiaria hybrid, Al makes complexes with some ligands such as organic-acid anions in the root symplast. The forages probably adapted to P starvation through high P-use efficiency. These experiments provide the first direct evidence we know of that organic acid anions within root tissue help detoxify Al in non-accumulator species such as the Brachiaria hybrid.  相似文献   
285.
Most reports of the studies on solubilisatioh of phosphate in liquid culture and soil suggested that organic acids produced by microorganisms are responsible for promoting the dissolution of phosphate. Sperber (11, 12), Louw and Webley (7) and Duff, Webley and Scott (2) studied the production of acids by cultures of some phosphate dissolving fungi. actinomycetes and bacteria and observed that among the acids produced in liquid medium, hydroxy carboxylic acids such as lactic and 2-ketogluconic acids were responsible for solubilisation of phosphates. In the present studies, apart from the culture of Bacillus megaterium var. phosphaticum isolated from phosphobacterin which had been obtained from USSR. Indian strains of Bacillus megaterium, Bacillus circulans and Escherichia freundii isolated and identified by Sundara Rao and Sinha (13) were used. These studies were undertaken to find out different types of nonvolatile acids produced in Pikovskaya's (9) liquid medium.  相似文献   
286.
Rao  Dean  Liu  Panyang  Zou  Luyi  Teng  Yue  Yu  Hongyan 《植物病害和植物保护杂志》2021,128(6):1487-1500
Journal of Plant Diseases and Protection - Replant problem in agriculture is popular and has restricted the development of tobacco industry. To identify the key soil factors affecting replant...  相似文献   
287.
Okra (Hibiscus esculentus) whole seeds and their kernels were analysed for their nutrient composition. They were rich in protein as well as fat. Most of the protein and fat of the seed is accumulated in the kernel while crude fiber is concentrated in the seed coat or hull. Its essential amino acid composition was nearly equal to that of the WHO/FAO reference pattern (1973), but lower than that of whole egg protein; its chemical score was 67. Diets containing whole seed and kernel protein at the 10% level were fed to weanling rats both in the raw and cooked forms for 4 weeks. Dry matter digestibility and protein digestibility of whole seed diets were significantly lower than the kernel diets. Cooking improved PER and NPU values of both the whole grain and kernel diets. These results indicated that dietary fiber present in the hull of Okra seed as well as heat labile antinutritional factors present in the seed hinder Okra seed protein utilization.  相似文献   
288.
Determination of the physico-chemical characteristics of composite soft wheat flours in which 5–25% (w/w) of the wheat flour was replaced with untreated, roasted and germinated black gram (Phaseolus mungo) flours (BGF) showed that when roasted BGF comprised 20% (w/w) of the blend, the increases in the ash and protein contents were 123% and 35%, respectively. The values for the gluten contents and the Zeleny and sodium dodecyl sulphate sedimentation test volumes for the composite flours indicated a weakening effect of BGF on the quality of soft wheat flour proteins, which could be beneficial for the preparation of biscuits (cookies). The alkaline water retention capacity values increased with the increasing addition of differently processed BGFs. Biscuit baking studies indicated that the diameter and spread ratio of biscuits were reduced, while the thickness increased, with increasing addition of all three BGFs, but the maximum reduction in diameter was observed with the addition of germinated BGF. The hardness value for biscuits increased with the addition of BGFs, but the effect was minimal with roasted BGF and maximal with germinated BGF. The surface grain score was reduced with increasing addition of BGF, but, in general, the roasted BGF showed the minimum adverse effect. From the overall biscuit making quality, addition of untreated BGF at the 15% level and of roasted and germinated BGFs at the 20% level were considered optimal for supplementing wheat flour.  相似文献   
289.
Thirty-three peanut cultivars were examined for their alpha-1,6 and beta-1,4 galactosidase activities and oligosaccharide contents along with proximate compositions. The average moisture, protein, fat, ash, and carbohydrate contents were: 4.9%, 26.6%, 43.1%, 2.3% and 23.1%, respectively. The corresponding coefficients of variation were: 5.2%, 10.1%, 7.2%, 7.8% and 15.7%, respectively. Raffinose and stachyose contents (%) ranged from 0.05 to 0.12 and 0.31 to 0.61, respectively. The specific activity (micromol product/min/mg protein) of crude preparation of alpha-galactosidase for the 33 cultivars ranged from 1.096 to 2.784 for the non-germinated seeds and from not being detected in some samples up to 2.432 for the germinated seeds; the mean values for non-germinated and germinated seeds were: 1.781 and 1.410, respectively. The specific activity of beta-galactosidase ranged from 0.101 to 1.727 in the non-germinated seeds and from not being detected in some samples up to 0.898 in the germinated seeds. Germination decreased the activity of both galactosidases significantly (p < or = 0.05).  相似文献   
290.
The distribution of alpha -amylase, protease, lipoxygenase, polyphenol oxidase and peroxidase in wheat roller flour mill streams was studied. Break flours had relatively less alpha -amylase and protease activity than reduction flours both on flour weight and a protein basis. Among the different flour streams, the 5thand 6threduction passage had the highest alpha -amylase activity, while the 4threduction passage had the highest protease activity. The lipoxygenase activity was concentrated mostly in the last break and the reduction streams, whereas polyphenol oxidase activity was highest in break flour streams. Peroxidase activity was distributed unevenly among the different mill streams. The lipoxygenase, polyphenol oxidase and peroxidase were highly concentrated in different bran fractions. Except for protease, the other enzymes were concentrated in the «atta», a milling by-product comprising refined flour, bran and shorts; and are least active in semolina (farina).  相似文献   
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