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101.
Two experiments were carried out in which a total of 602 pigs were slaughtered after being held in lairage for periods ranging from less than one hour to 21 hours. In the first experiment the pigs were handled under ideal conditions and slaughtered at the University of Bristol slaughterhouse; in the second the pigs were killed at a commercial plant. Blood samples collected at exsanguination were analysed for indices of stress. There were no consistent effects of time in lairage on the levels of lactate and creatine phosphokinase. Plasma cortisol and beta-endorphin levels were reduced by lairage for three hours or more in the first experiment and cortisol was reduced by lairage for two hours or more in the second; beta-endorphin was not measured in the second experiment. A period of rest in lairage allowed the pigs to recover from transport and the associated handling and the recovery appeared to be complete within two to three hours. 相似文献
102.
Filarial parasites, Litomosoides carinii and Setaria cervi, showed great susceptibility to the oxidants generated in vitro by the xanthine/xanthine-oxidase system. In order to counteract such injurious effects, both the filariids possessed an active antioxidant enzymes system. Superoxide dismutase, catalase and glutathione peroxidase were detected in appreciable amounts but glutathione reductase and glucose-6-phosphate dehydrogenase in very low quantities. The former three enzymes were also found to be released by the parasites into the ambient medium. The released enzymes may be responsible for scavenging the host-generated oxidants present in the immediate surroundings of the parasites and thereby enabling them to live comfortably in the host. This Institute-based antifilarial agent namely Compound 82/437 which is 2,2'-dicarbomethoxylamino-5,5'-dibenzimidazolylketone, markedly inhibited catalase and glutathione peroxidase of both L. carinii and S. cervi. The compound, therefore, appears to render the filariids prone to H2O2 toxicity leading to penultimate damage. 相似文献
103.
Selamectin, a novel avermectin compound, was evaluated for its efficacy against naturally occurring infestations of Psoroptes cuniculi and Sarcoptes scabiei. A total of 42 New Zealand rabbits with psoroptic mange and 37 Angora rabbits with sarcoptic mange were used in the present study. On day 0, infested rabbits were treated topically with either selamectin at minimum dose of 6 mg kg(-1) (6-18 mg kg(-1) for New Zealand rabbits, n = 31 and 10-12 mg kg(-1) for Angora rabbits, n = 23) or vehicle only (control groups, n = 11 for New Zealand rabbits, n = 14 for Angora rabbits). The efficacy of selamectin was assessed both clinically and parasitologically by the presence or absence of viable mites. Rabbits were scraped for sarcoptic mites on days 7, 14, 28, 42 and 56 and had otoscopeic and/or microscopic examination for the detection of Psoroptes mites on days 7, 14, 42 and 56. Fisher's exact test was used to assess differences between the vehicle and selamectin treatment in the number of rabbits without mites (cure rates) on each assessment date. It was found that significantly fewer selamectin-treated rabbits had mites detected on skin scrapings (for S. scabiei) or otoscopeic and/or microscopic examination (for P. cuniculi) (P < 0.01) than the vehicle group. Results of the present study suggest that selamectin is effective against naturally infestations of P. cuniculi and S. scabiei in rabbits. 相似文献
104.
Koratigere Parameshanayka Devaraja Ranjith Kumar Ellur Pankaj Ashok K. Singh Anumanahalli Puttasawamy Abhishek Gowda Anil Sirohi 《Plant pathology》2023,72(1):179-194
The rice root-knot nematode (RRKN), Meloidogyne graminicola, is one of the major pests of the rice–wheat cropping system. Resistance against M. graminicola in rice could be most valuable in alleviating this problem. The host response of 75 Oryza genotypes was examined at three day/night temperature regimes, 29/26°C, 34/31°C and 38/35°C, in Pluronic gel as well as in soil. Out of the 75 selected rice genotypes, only Zhenshan 97 B exhibited high resistance to this set of temperature regimes, with the least number of galls/root system. At 34/31°C, more second-stage juveniles (J2s) were hatched and J2 population densities in roots of the susceptible rice genotypes increased significantly compared with those of plants grown at the 29/26°C. In resistant genotypes, only a few J2s penetrated roots and developed into mature females. The histopathological studies revealed that in susceptible rice genotypes at high-temperature regimes, the multinucleate giant cells were well developed. The results presented in this study revealed that an increase in temperature had a significant effect on the resistance of rice genotypes and resistance appeared more pronounced in genotype Zhenshan 97 B. This resistant genotype can be used in marker-assisted selection to develop resistant elite cultivars. 相似文献
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107.
Experiments were conducted to analyse the effect of 3-year-old grass plots, under a cut-and-carry system, on the yields of maize and groundnut crops, and at the same time to compare the relative importance of the water-stable aggregates and the nitrogen status of the soil. The N reserves, organic carbon and water-stable aggregate contents of soils were higher under grass plots than in the ploughed-up-fallow plots. Maize yields showed a close correlation with total soil N, mineralized N after incubation for 20 days, and water-stable aggregate contents; groundnut yields showed close correlation only with water-stable aggregates. The effects of the variations in soil N and in the water-stable aggregate content of the soil on the yields of maize and groundnuts were examined by multiple regression analysis of data from a large number of plots. 相似文献
108.
Anthocyanins in Cabernet Sauvignon grapes and wines were elucidated by HPLC-MS/MS. Major anthocyanins in Cabernet Sauvignon grape extract are malvidin 3-O-glucoside and malvidin 3-O-acetylglucoside. In matured wine, anthocyanins are transformed to anthocyanin-vinyl derivatives, ethyl bridged anthocyanin-flavanol adducts, and anthocyanin-flavanol adducts. The major anthocyanin pigments are malvidin 3-O-glucoside-pyruvate, malvidin 3-O-acetylglucoside-pyruvate, malvidin 3-O-coumaroylglucoside-pyruvate, malvidin 3-O-glucoside-4-vinylphenol, malvidin 3-O-acetylglucoside-4-vinylphenol, and malvidin 3-O-coumaroylglucoside-4-vinylphenol. The presence of syringetin 3-O-glucoside and syringetin 3-O-acetylglucoside has been established for the first time in grape and wine. 相似文献
109.
To see the deleterious effects of excess chromium (Cr) on carrot (Daucus carota L.) the cv. ‘Pusa Keshari’ was grown in refined sand under controlled glasshouse conditions with a complete nutrient solution (without Cr) for 48 days. On the 49th day, pots with two plants each were separated into three sets. One set served as a control. In each of the other two sets, Cr was supplied as dichromate at 0.1 and 0.5 mM to the basal nutrient solution. At 0.5 mM Cr toxicity symptoms appeared at d 52 (4 days after Cr supply) as reduction in growth and leaf size and loss of turgor. Old leaves became chlorotic and wilted. Chlorosis intensified and turned necrotic in another few days. These symptoms spread to next upper leaf. The development of chlorosis in leaves was delayed in plants receiving 0.1 mM Cr. At excess Cr (0.5 mM) in carrot, the biomass, concentration of chlorophylls a and b, iron (Fe), sulfur (S), and phosphorus (P) in shoots, and activity of catalase (CAT) in leaves decreased whereas the concentration of Cr and the activity of peroxidase (POX), superoxide dismutase (SOD), ribonuclease (RNAse), and acid phosphatase (A P) in leaves increased. 相似文献
110.
AbstractTo harness the benefits of system of rice intensification (SRI) coupled with short-duration rice-hybrids, 10 multi-location “On-Farm-Trials” were conducted during 2007–2012 in Himachal Pradesh, India. The study revealed that rice-hybrids were more productive with higher resource-use-efficiency than high-yielding-varieties (HYVs) both under conventional-transplanting (CT) and SRI. The Arize-6129 rice-hybrid exhibited wider adaptability for CT and SRI under varying bio-physical regimes. Arize-6129 rice-hybrid under SRI in rainfed medium-fertility, irrigated medium-fertility and irrigated high-fertility situations yielded about 6.75–6.88, 7.00–7.86, and 7.58-8.32 t grains ha?1, respectively; with respective net returns of INR 48,517–49,761, 57,240–62,603 and 64,333–66,748?ha?1. After Arize-6129, “Swift,” “US-312,” and “PAC-801” are the alternate options for SRI-cultivation. Adoption of SRI using short-duration rice-hybrids under participator-mode technology-transfer program, led to higher net income gains by 29.4% over CT in study area. Overall, SRI using short-duration rice-hybrids has provided new opportunities to enhance rice productivity and profitability to transform rural-livelihoods in wet-temperate NW Himalayas. 相似文献