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41.
Twenty-eight Angora goat doelings (average BW 22.1 kg) were used in a 150-d study to examine the effects of dietary CP level and degradability on mohair fiber production. A 2 x 2 factorial arrangement was instituted using conventional, solvent-extracted soybean meal (high degradability) or expelled, heat-treated soybean meal (low degradability) incorporated into low- (12%) or high- (19%) CP diets. Grease and clean mohair weights were greater (P less than .05) in goats fed the diets containing 19% CP. Mohair fiber diameter was not affected (P greater than .10) by dietary CP level. Clean mohair weight tended (P less than .08) to be higher in the goats fed diets containing expelled, heat-treated soybean meal. Body weight gains were not affected (P greater than .10) by CP level or degradability, whereas DMI increased (P less than .01) with increasing CP level. Ruminal fluid pH and total VFA concentrations were not affected (P greater than .10) by diet. Ruminal ammonia N concentration increased (P less than .05) as CP level in the diet increased, and postprandial changes in concentrations were less noticeable in the group fed expelled, heat-treated soybean meal. Plasma urea N (P less than .001) and total protein (P less than .01) concentration increased as dietary CP level increased. Plasma glucose was elevated (P less than .001) 2 h after feeding in the goats fed conventional, solvent-extracted soybean meal, whereas glucagon concentrations were greater at 0 and 4 h in the group fed expelled, heat-treated soybean meal.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Abstract.— Growth, histological lesions, and biochemical changes were investigated in channel catfish Ictalurus punctatus fed various concentrations of moniliformin with or without fumonisin B1. Channel catfish (average initial weight, 1.5 g) were fed diets formulated to contain 0, 20, 40, 60, and 120 mg moniliformin/kg; 0, 20, and 40 mg fumonisin B1/kg, or two combinations of moniliformin and fumonisin B1 for 10 wk. Fish fed diets with the lowest concentration of moniliformin or fumonisin B1 (20 mg/kg diet) had significantly (P < 0.05) less weight gain than the control fish. Increasing the level of moniliformin in the diets resulted in a linear decrease in weight gain. Overall mortality of fish was 4% and not related to treatment effects. Hematocrit was significantly (P < 0.05) lowered by 60‐mg moniliformin/kg diet or 40‐mg fumonisin B1/kg diet. Dose‐dependent increases in serum pyruvate concentration and ratio of free sphinganine to free sphingonine were obtained with increasing concentration of dietary moniliformin and fumonisin B1, respectively. Mean serum pyruvate level was significantly (P < 0.05) higher in fish fed the diet containing 60‐mg moniliformin/kg diet. Addition of fumonisin B1 (40 mg/kg) to the diet containing 40‐mg moniliformin/kg significantly increased the serum pyruvate level above that of the control. Also, the lowest concentration of fumonisin B1 (20 mg/kg diet) significantly (P < 0.05) increased the ratio of sphingolipids. Combinations of moniliformin and fumonisin B1 at levels of 20:40 and 40:40 mg/kg diet did not significantly change the effect of fumonisin B1 on the ratio of sphingolipids. The only tissue lesions observed in liver and heart were smaller nuclei of cells in livers of fish fed diets containing the two highest levels of moniliformin and the combinations of the two toxins.  相似文献   
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This study estimated the prevalence of methicillin resistant Staphylococcus aureus (MRSA) in nasal swabs of 458 horses in western Canada. The rate of colonization was 1.3% ± 5.84% [95% confidence interval (CI)], a rate similar to those reported elsewhere. Colonization tended to be transient and seemed unrelated to stress or administration of antimicrobials. Five of the 6 isolates were Canadian epidemic MRSA-5, a human clone that appears to predominate in horses in North America. The other isolate was spa type 539 (t034), a sequence type 398 strain, and this is the first report of this clone in horses in North America. Surveillance is warranted because of the potential of MRSA to cause disease in horses and humans.  相似文献   
47.
A 1-year-old spayed female Persian cat with alopecia and weight loss had numerous variably ulcerated dermal nodules. Cytologic examination of an aspirate of one of the nodules revealed pyogranulomatous inflammation along with septate hyphae and basophilic round bodies, 0.5–1.0 μm in diameter, surrounded by a thin clear halo (arthrospores). The cytologic diagnosis was dermatophytic pseudomycetoma. Histologically, there were dermal granulomas containing poorly staining, septate hyphae with bulbous spores embedded within abundant amorphous eosinophilic material (Splendore-Hoeppli reaction), and the histologic diagnosis was pseudomycetoma-associated chronic multifocal severe granulomatous dermatitis with lymphocytic perifolliculitis and furunculosis. Microsporum canis was cultured from the lesion. Pseudomycetomas are distinguished from fungal mycetomas, or eumycotic mycetomas, by the findings of multiple lesions, lack of a history of skin trauma, an association with dermatophytes, most commonly Microsporum canis , and, histologically, lack of true cement material and a more abundant Splendore-Hoeppli reaction in pseudomycetomas. Additionally, pseudomycetomas differ from dermatophytosis, in which lesions are restricted to epidermal structures. Persian cats have a high incidence of pseudomycetoma formation, suggesting a heritable predisposition. The prognosis is fair with systemic antifungal therapy. When examining cytologic specimens from Persian cats with single or multiple dermal nodules, especially if pyogranulomatous inflammation is present, a diagnosis of pseudomycetoma should be suspected and is warranted if arthrospores and refractile septate hyphae are present.  相似文献   
48.
1. The effects of reserpine on plasma glucose, FFA and cholesterol and on adrenal cholesterol were determined in 1‐ and 21‐d‐old chicks over a 24‐h period.

2. Irrespective of age, reserpinised chicks became hyperglycaemic and hypocholesteraemic, their stores of adrenal cholesterol were depleted and the mobilisation of the lipid was impaired. The response of the older bird was quantitatively larger than that of the younger bird.

3. Propranolol prevented the increase in plasma glucose concentration seen 1 h after reserpine but it did not affect subsequent changes.

4. It is concluded that reserpine acts as a stressor and it is shown that its effects have not been entirely overcome after 24 h.  相似文献   

49.
基于多指标协同的草莓水肥耦合综合调控   总被引:3,自引:0,他引:3  
为探寻草莓最优水肥组合,设置灌水和施肥二因素三水平共9个处理,分析不同水肥耦合对草莓产量、果实品质、水肥利用效率多个指标的影响。引入AHP层次分析法和熵权法对3类因素9个指标进行多层赋权,运用基于博弈论的组合赋权法获得各单一指标最终权重,基于TOPSIS法构建草莓综合生长评价体系,并以高产、高品质、高效为目标建立草莓水肥耦合响应数学模型。结果表明,水肥耦合作用对草莓的单果质量、产量、水分利用效率和肥料利用效率的影响极显著,对品质无显著影响。中水、高肥灌溉下草莓的单果质量最大,中水、中肥灌溉下草莓的产量和可溶性糖含量最优,中水、低肥灌溉下草莓的糖酸比和可溶性蛋白质含量表现最优,低水、中肥灌溉下草莓的可溶性固形物含量、水分利用效率和肥料利用效率最优,低水低肥灌溉下草莓的维生素C含量最大。综合协调各指标,赋权值最高为产量(0. 264 1),最低为可溶性蛋白质含量(0. 059 5);多指标综合评价最优水肥处理为中水中肥(T5)。解析草莓综合生长对水肥耦合的响应模型,灌水量及施肥量的单因素效应均为开口向下的抛物线;当灌水量编码值为-0. 23(2 375. 1 m~3/hm~2)、施肥量编码值为-0. 02(1 825. 88 kg/hm2~)时,草莓综合评分最高。以综合评分最大值的90%划分水肥耦合闭合区域,得到最佳灌水和施肥区间分别为灌水量2 268~2 520 m~3/hm~2、施肥量1 759. 88~1 869. 87 kg/hm~2。  相似文献   
50.
Infectious salmon anaemia (ISA) is a highly virulent viral disease of Atlantic salmon that causes massive economic losses to infected aquaculture operations. Our goal was to detect and map quantitative trait loci (QTL) that confer resistance to ISA in an admixed commercial strain of Atlantic salmon that was largely founded from the Saint John River (SJR) in North America. Full‐sibling families were challenged with a virulent strain of ISA virus. Mortality was tracked during two annual trials with individual fish that survived to the end of the trial being classified as ‘resistant’, and those that died were classified as ‘susceptible’. Ten families with intermediate levels of mortality and an average size of 54.2 individuals were chosen for genotyping with a 50K SNP array designed for the SJR strain. Single nucleotide polymorphisms that were segregating within families were first used to make a composite 11K female linkage map that was then used to find the positions of QTL for ISA resistance using a half‐sib model. The dam‐based HS model detected a total of three QTL for ISA resistance including an experiment‐wide significant QTL on Ssa25 that accounted for 8.3% of the phenotypic variance and chromosome‐wide significant QTL on Ssa03 and on Ssa04 that accounted for 6.0% and 6.6% respectively. We conclude that classic linkage mapping within families continues to be an important method of detecting QTL for oligogenic traits in strains founded from multiple populations. Single nucleotide polymorphisms with moderate trait effects are being used to select within families for more ISA‐resistant strains of Atlantic salmon.  相似文献   
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