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211.
The present study was designed to characterize phenotypically and genotypically nine Arcanobacterium abortisuis strains collected from specimen of pigs in a period of nine years. All nine A. abortisuis strains and A. abortisuis reference strain DSM 19515 displayed a synergistic hemolytic reaction with Staphylococcus aureus β-hemolysin, Rhodococcus equi, and Arcanobacterium haemolyticum indicator strains and showed the typical biochemical properties of this species. The species identity could be confirmed by identification and sequencing of the 16S-23S rDNA intergenic spacer region (ISR), which appeared to be a useful target for genotypic characterization of this bacterial species. The A. abortisuis strains of the present study were isolated from specimen of pigs together with various other bacterial species indicating that the pathogenic importance of this newly described species remains to be elucidated.  相似文献   
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213.
Five clinically health goats were injected with sulfadimethoxine and sulfadimethyloxazole in a single dose of 100 mg/kg b. wt. by intravenous route. Highest concentration levels of sulfadimethoxine and sulfadimethyloxazole in rumen were detected 1 hour following intravenous injection, then the concentration for both compounds declined at 12 and 8 hours post administration, respectively. In addition, both types of sulfonamide completely disappeared in ruminal fluid samples taken after 24 and 12 hours, respectively. The rate of acetylation for sulfadimethoxine and sulfadimethyloxazole were nearly similar and occurred to a high extent in ruminal fluid (22.95 and 23.72%, respectively). On the other hand, both tested drugs increased significantly the ruminal gas production from the first to eight hours after i.v. injection in goats. Changes in the serum enzyme activities (SGOT, SGPT and alkaline phosphatase) observed with sulfadimethoxine and sulfadimethyloxazole, and represented by a significant decrease in the activity of SGOT and SGPT level, alkaline phosphatase 4 hours sulfadimethoxine and in GOT/GPT ratio 24 and 48 hours after i.v. injection, respectively. The creatinine clearance was significantly decreased after 4 hours following the i.v. administration of sulfadimethoxine and sulfadimethyloxazole in goats.  相似文献   
214.
Groups af White Leghorn chicks obtained from dams deprived on selenium (Se), were fed from hatching a low-Se-vitamin E basal diet alone, or supplemented with 0.02, 0.04, 0.06 or 0.08 mg Se/kg diet, as sodium selenite (Na2SeO3 · 5H2O), wheat, barley or fish meal. Prevention of the Se-vitamin E deficiency responsive disease exudative diathesis (ED) as it was clinical observed, induction of the plasma Se dependent enzyme glutathione peroxidase (GSH-Px) activity, and Se concentration in the cardiac muscle were observed to be dietary Se level and source dependent. Slope ratio assay was applied to estimate the biological availability of Se in the natural sources relative to Se in sodium selenite. For the prevention of ED, the bioavailability of Se in wheat, barley and fish meal was 99, 85 and 80 %, respectively. The increase in the plasma GSH-Px activity revealed a bioavailability for Se in wheat, barley and fish meal of 79, 71 and 66 %, respectively. Using retention of Se in the cardiac muscle as the bioassay, a bioavailability of 108, 87 and 100 % was calculated for wheat, barley and fish meal Se, respectively.  相似文献   
215.
The efficiency of indirect haemagglutination (IHA) and immunoelectrophoresis (IEP) as means of detection of cystic hydatid infection in camels was investigated. Both IHA and IEP showed very low detection rates of antibody in camel sera. The IEP showed 84 p. 100 specificity and 36 p. 100 sensitivity while the IHA showed 69 p. 100 specificity and 43 p. 100 sensitivity. These results are discussed.  相似文献   
216.
Two field experiments were carried out during 1982/83 and 1983/84 seasons at Experimental Farm of National Research Centre at Shalakan, Kalubia Governorate, Egypt, to study the reversal effect of glyphosate induced phytotoxicity on growth and yield and its components of faba bean by the application of growth factors, i.e., growth regulators, amino acids and nutrient elements at different concentrations. A split plot design with four replications was used in both seasons. The obtained results indicated clearly that: Glyphosate at the two higher doses exhibited varying degrees of phytotoxic symptoms and reduced all the faba bean plant characters except the number of branches/plant. GA3 alone or in a mixture with cytokinin reversed the phytotoxic effect of the glyphosate herbicide on decreasing the plant height. Cytokinin at 4/1000, phenylalanine and tryptophan at both levels, as well as GA3 at 50 ppm, reversed the phytotoxic effect of the glyphosate herbicide on decreasing the dry weight/plant cytokinin at 4/1000, tryptophan at both concentrations, as well as, phenylalanine at 500 ppm, reversed the phytotoxic effect of the glyphosate herbicide on decreasing the number and dry weight of pods, seed yield per plant and per ha.  相似文献   
217.
218.
The pathogenicity for sheep and goats of the virus strain that caused acute rinderpest in cattle and domestic buffalo in Sri Lanka after an interval of over 40 years has been examined. The results show that it can cause overt clinical disease in goats, but only mild or unapparent infection in sheep. The disease was transmitted from infected sheep to in-contact susceptible sheep and calves.  相似文献   
219.
Genital bovine papillomavirus infection was observed for the first time in the Al-Ahsa region of Saudi Arabia. The disease involved 1 female and 2 male 2-4-year-old crossbred cattle. Fibropapillomas (warts) were limited to the prepuce and vulva. Electron micrographs of thin sections of the lesions revealed the presence of intranuclear viruslike particles. Using a broadly cross-reactive rabbit polyclonal antiserum directed against papillomavirus group-specific antigens, the infection was confirmed by immunohistochemical staining of paraffin-embedded tissues to be due to a papillomavirus. Staining with a series of monoclonal antibodies of various specificities indicated that the virus was bovine papillomavirus type 1. Attempts to propagate the virus by inoculation of tumor homogenates onto chorioallantoic membranes of chicken embryos were unsuccessful.  相似文献   
220.
The germination behaviour of glyphosate-treated seeds of two wheat cultivars was investigated. Ten concentrations of the herbicide (480 g/L.) ranged from zero to 260 g. a.i./Fed. were applied to the dry seeds by soaking for two hours. Germination was then conducted in petri dishes on filter paper at average daily maximum and minimum temperatures of 19.65 and 6.15 °C in the laboratory. Seedling growth behaviour was recorded periodically at the 4th, 7th and 10th day of germination.
The results indicated that glyphosate treatment at different concentrations did not affect the germination percentage in both wheat cultivars. On the other hand, in comparison to the control, the herbicide treatment caused significant reduction in maximum seedling root and shoot lengths. The reduction increased proportionally by increasing the herbicide concentration. Treatments with high concentrations of the glyphosate caused significant reduction in total root number per seedling in cv. Sakha 8. At concentrations of 260, 130 and 65 g a.i./Fed. all seeds exhibited root aberration in both wheat cultivars.
Clear variation in cultivar susceptability to glyphosate treatment was observed, particularly at concentrations lower than 65 g a.i./Fed.
However, cv. Giza 155 seemed to possess better survival to glyphosate treatment than cv. Sakha 8 concerning root inhibition percentage and seedling part measurements. The results indicated the practical importance of the reactions of different genetic codes to the herbicide in the field including the crop and the weeds.  相似文献   
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