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The influence of the lipid extraction process on both macroscopic and microscopic characteristics of nonwaxy rice starch gelatinization in excess water was examined. Surface lipids extraction did not change the thermodynamics of starch gelatinization but lead to a significant reduction (33%) in the enthalpy of starch-lipid complex melting at high temperature, resulting in less viscous dispersions. Internal lipid extraction using hot aqueous alcoholic solutions resulted in an irreversible increase in starch granule diameter (50% increase in D[4,3]) and a dramatic change in cooking characteristics of the starch. Instead of the bimodal swelling observed for native nonwaxy rice starch, only one broad transition in swelling, solubility, granule size, and viscosity was observed in the case of the totally defatted starch. While the total removal of lipids resulted in a slight increase in starch swelling at intermediate temperatures, the harshness of the process caused irreparable changes leading to notably lower swelling at high temperatures.  相似文献   
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本文从常用的水库调洪演算推导出了一些简单关系,为初选滞洪水库的库容提供了一个可靠的依据。分析表明:所需的滞洪库容与洪量之比(滞洪库容因子)主要取决于入流与出流峰值之比(洪峰流量因子)、泄流型式以及入流过程线的形状。对于相同的洪水过程线,要取得相同的削峰效果,淹没出流比自由溢流能更为有效地减小滞洪库容。对于淹没泄流和自由溢流的滞洪水库库容因子与洪峰因子之间的关系可近似用两个代数式来表示。使用美国农业部水土保持局的关系曲线对所需的滞洪库容估计不足。  相似文献   
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The effect of organic or conventional feeding on the immune response of pigs was determined using organic or conventional housing in a pig fattening unit. The experimental design involved four pens of four animals per housing and diet combination (organic housing and organic nutrition; organic housing and conventional nutrition; conventional housing and organic nutrition and conventional housing and conventional nutrition). The IgM, IgA and IgG responses against intramuscularly injected bovine thyroglobulin were determined as indicators of the antigen-specific immune responsiveness. Some general health and welfare related parameters were evaluated by measuring haptoglobin concentrations at selected times; blood lactate concentration was measured at slaughter. Conventional housing led to a higher IgG response three weeks after the first immunisation. Organic housing led to lower haptoglobin and lactate concentrations at slaughter, indicating a higher stress resistance in these pigs. No major differences between the two feeding types were found. We conclude that the immune responses following either a conventional or an organic diet are comparable, whereas organic housing can increase stress resistance at slaughter compared to conventional housing.  相似文献   
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OBJECTIVES: To identify features of canine idiopathic pulmonary fibrosis (CIPF) using high-resolution computed tomography (HRCT), and to correlate these features with clinical stages of the disease. METHODS: Ten dogs with signalment, history and clinical signs highly suggestive of CIPF were investigated. Thoracic radiography, haematology and biochemistry profiles, bronchoscopy and bronchoalveolar lavage and HRCT were performed in each case. The dogs were classified as having mild, moderate or severe stages of the disease based on their clinical presentation and radiographic signs. Features identified by HRCT were correlated with these disease stages. RESULTS: HRCT showed a spectrum of pulmonary changes and it was possible to match some of these to the stage of CIPF. CLINICAL SIGNIFICANCE: HRCT is used extensively in humans in the diagnosis and treatment planning of idiopathic pulmonary fibrosis. This preliminary study identifies the high-resolution computed tomographic features of CIPF in a small group of dogs. With further work it may be possible to use HRCT as a non-invasive tool for diagnosing, staging and therapeutically monitoring CIPF.  相似文献   
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Although the epitheliochorial placenta of ruminants does not allow passage of immunoglobulins from dam to foetus specific antibodies have been detected at birth in calves born to Schistosoma mattheei-infected cows. The present study determined the prevalence of calves born with specific antibodies for S. mattheei and the origin of these antibodies. For the determination of the prevalence, 100 calves born to infected mothers in an endemic area (Zambia) were examined, 24 were seropositive. To study the origin of these antibodies placentomes of 40 naturally S. mattheei-infected cows were examined for the presence of schistosome eggs and lesions which could explain foetal priming and/or leakage of maternal antibodies and/or antigen into the foetus. Tissue damage and schistosome eggs were observed on the maternal as well as the foetal side of the placentomes. In order to determine the specific nature of the antibody response, antibody profiles against soluble adult worm antigen preparation (SWAP) of S. mattheei were compared by Western blot between dams and their newborn calves (n = 8). The specific recognition profiles were identical for the seropositive calves and their dams on SWAP mattheei. Identical recognition profiles between dams and calves were also observed when sera were analysed on Escherichia coli, a pathogen of which the foetus should be free, and would indicate passive antibody transfer from the dam. In conclusion, the present study shows that S. mattheei could induce placentome lesions and that eggs can cross the placenta. Consequently, foeti can come into contact with S. mattheei antigens in utero, and might also contain maternal antibodies from leakage through placentome lesions. As such, the infection status of the mother could have far reaching effects on the immunological status of her offspring and modify their reaction upon infection.  相似文献   
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The aim of the present investigation was to examine the inclusion of the dried herb Echinacea purpurea (L.) MOENCH as feed additive in diets of sows, piglets, and grower/finisher pigs on growth performance, blood picture, plasma enzymes including proliferation of lymphocytes, antibody status, and protein and immune globulin content of colostrum. The control groups were supplemented with alfalfa meal. The sows (total 36) received 0%, 1.2%, or 3.6% Echinacea cobs in the diet from day 85 to day 110 of gestation and 0%, 0.5%, or 1.5% Echinacea cobs up to day 28 of lactation. No significant differences were found for growth performance, weight loss, blood picture, plasma enzymes, and colostrum composition. Performance of the sucking piglets was not impaired either during lactation or during a 4 week observation period after weaning. The health status was similar in all treatment groups. In a second experiment, lasting 6 weeks, with 36 piglets (5.8-22.1 kg body weight), 1.8% Echinacea cobs, or 20 mg/kg feed Flavomycin were supplemented. No significant differences were found for the recorded parameters. Feed conversion ratio (kg feed/kg gain) of the Echinacea group was slightly (4%) increased (1.54 vs. 1.60). In a third trial, 48 grower/finisher pigs were used during a 9-week experimental period with two supplementation phases (weeks 1-3 and weeks 7-9). The experimental groups received 0%, 1.5% cobs or 4-6 ml pressed juice (commercial standard) per day respectively. Vaccination with Swine erysipelas was implemented in weeks 1 and 5 to determine the specific immune response. Growth performance and blood picture for all groups were similar, however, feed conversion of both Echinacea supplemented groups was significantly (p < 0.03) better than of the unsupplemented control group (2.44 vs. 2.51). In addition, the Swine erysipelas antibodies showed a marked significance (p < 0.05) in regard of altitude in both supplemented groups. It is concluded, that E. purpurea might be used as a feed additive to achieve immune stimulating efficiency in pig production and increase feed-to-gain-conversion. The efficiency of cobs is comparable to a commercial juice product.  相似文献   
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