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81.
To evaluate the magnitude of copper deficiency in Northern India and to examine the various haematobiochemicals, enzymes,
vitamins and immune functions affected by copper deficiency, and to identify the parameters which can be of diagnostic importance
in copper deficiency, a survey was conducted in 12 districts of Northern India. Significant deficiency of copper was observed
in soil, fodder and serum samples of buffalo heifers. Fifty hypocuperaemic buffalo heifers were selected from these areas
and were randomly divided into two groups, A and B. The heifers in group A were provided with mineral mixture containing copper
sulphate and in group B without copper sulphate. Significant (p < 0.01) improvement in serum ceruloplasmin level was observed within 30 days of treatment, while significant (p < 0.01) improvement in monoamine oxidase and liver cytochrome oxidase was observed at the 60th day of treatment in group
A animals. Significant improvement was observed in T3 and T4, in the animals of group A within 60 days of treatment. The values of vitamin A and E showed significant (p < 0.01) improvement within 30 days of treatment. The phagocytic activity of neutrophils against Candida albicans significantly (p < 0.01) improved in group A within 60 days of treatment. Similarly, significant improvement in superoxide dismutase activity
in red blood cells was observed at the 30th day, and in total leukocytes and whole blood at the 60th day in group A animals.
Significant improvement in liver copper level was observed at the 30th day of treatment, while in group B the liver copper
was significantly (p < 0.01) depleted at the 60th day of experimentation. Additional copper supplementation improved growth performance significantly
in group A. 相似文献
82.
Cathepsin L, a major cysteine proteinase secreted by the parasite plays a pivotal role in various aspects of its pathogenecity. The enzyme takes part in nutrient acquisition by catabolizing host proteins to absorbable peptides, facilitates the migration of the parasite through the host intestine and liver by cleaving interstitial matrix proteins such as fibronectin, laminin and native collagen and is implicated in the inactivation of host immune defenses by cleaving immunoglobulins. Recently, Cathepsin L has been shown to suppress Th1 immune response in infected laboratory animals making them susceptible to concurrent bacterial infections. Accordingly, the protease has been recognized as an important target at which parasite intervention strategies should be directed. Fluke Cathepsin L cysteine proteinases are also reported as sensitive and specific markers for the immunodiagnosis of fasciolosis in ruminants. Further, vaccination of laboratory or large animals with these proteases resulted in a significant reduction in fluke burden and/or fecundity. 相似文献
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84.
A 2-year study was conducted to determine the effects of tillage and cropping systems on soil moisture balance, growth and yield of pearl millet (Pennisetum glaucum (L.) R.Br.). Three tillage treatments, viz. minimum tillage (one harrowing), conventional tillage (two harrowing, cross) and deep tillage (ploughing followed by two har-rowings), and four cropping systems, viz. monoculture of pearl millet, pearl miliet-clusterbean (Cyamopsis tetra-gonoloba (L.) Taub.) rotation, monoculture of pearl millet with 5 t ha−1 farm yard manure (FYM), and intercropping of pearl millet and clusterbean, were compared. Deep tillage improved the soil moisture storage, water use efficiency and grain yield of pearl millet while consumptive use of water was higher with minimum tillage. Total dry matter yield with deep tillage and conventional tillage was 23.2 and 10.2% higher than minimum tillage in the season 1, and the corresponding values for season 2 were 30.7 and 13.3%. The Pearl millct-clusterbean rotation and monoculture of pearl millet with the application of 5 t ha−1 FYM gave 17.2 and 6.1% higher yield than monoculture of pearl millet, respectively. Maximum water use efficiency was observed in rotation followed by FYM application. 相似文献
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(1) Mannitol fermentation is a reasonably reliable method for the detection of coagulase positive staphylococci in milk. This reliability can be improved if mannitol fermentation is carried out under anaerobic conditions.
(2) Among hemolytic strains of staphylococci isolated from milk, beta hemolytic staphylococci predominate. Bovine and sheep blood agar plates give similar hemolytic patterns, but the hemolysis is more pronounced on sheep blood agar.
(3) Gelatin liquefaction cannot be relied upon for the selection of coagulase positive staphylococci in milk.
(4) Urease production is a feature of the majority of coagulase positive staphylococci isolated from milk.
(5) Tellurite Glycine agar medium is not satisfactory for the selection of coagulase positive staphylococci in milk.
相似文献90.
ABSTRACT The abundance and diversity of phlD(+) Pseudomonas spp. colonizing the rhizospheres of young, field-grown corn and soybean plants were assayed over a 3-year period. Populations of these bacteria were detected on the large majority of plants sampled in the state of Ohio, but colonization was greater on corn. Although significant variation in the incidence of rhizosphere colonization was observed from site to site and year to year on both crops, the magnitude of the variation was greatest for soybean. The D genotype was detected on plants collected from all 15 counties examined, and it represented the most abundant subpopulation on both crops. Additionally, six other genotypes (A, C, F, I, R, and S) were found to predominate in the rhizosphere of some plants. The most frequently observed of these were the A genotype and a newly discovered S genotype, both of which were found on corn and soybean roots obtained from multiple locations. Multiple isolates of the most abundant genotypes were recovered and characterized. The S genotype was found to be phylogenetically and phenotypically similar to the D genotype. In addition, the novel R genotype was found to be most similar to the A genotype. All of the isolates displayed significant capacities to inhibit the growth of an oomycete pathogen in vitro, but such phenotypes were highly dependent on media used. When tested against multiple oomycete pathogens isolated from soybean, the A genotype was significantly more inhibitory than the D genotype when incubated on 1/10x tryptic soy agar and 1/5x corn meal agar. Seed inoculation with different isolates of the A, D, and S genotypes indicated that significant root colonization, generally in excess of log 5 cells per gram of root, could be attained on both crops. Field trials of the A genotype isolate Wayne1R indicated the capacity of inoculant populations to supplement the activities of native populations so as to increase soybean stands and yields. The relevance of these findings to natural and augmentative biocontrol of root pathogens by these bacteria is discussed. 相似文献