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71.
The effect on the early inflammatory response in the bovine mammary gland of a factor extracted from the cell wall of Staphylococcus aureus was studied. The insoluble factor was extracted from a 3h-culture, and was mixed with S. aureus from an overnight culture (OF) for experimental infection of a lactating quarter. Other quarters were infected with a 3h or an overnight culture (O). Five cows were used in the experiment. The O-quarters showed more severe clinical signs than seen in the 3h-and OF-quarters. Antitrypsin levels and NAGase concentrations were much reduced in the 3h-and OF-quarters. While the cell wall factor profoundly reduced the early inflammatory response, the effect on the final outcome of the infection was not determined.  相似文献   
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Kidneys and matched serum samples were obtained from 368 pigs slaughtered at three Victorian abattoirs, and originating from 42 farms. Macroscopic lesions (white spots) were observed on 102 of the kidneys. Serum samples were tested by the microscopic agglutination test (MAT) and by an IgM enzyme immunoassay (EIA). Kidneys were cultured for leptospires, examined histologically after Warthin-Starry silver staining and after immunogold silver staining (IGSS), and tested for leptospiral DNA by DNA hybridization. Forty-four infected pigs were identified by culture or immunogold silver staining of kidneys or by high MAT titres (greater than or equal to 1024). Infection was demonstrated in 7.5% of visibly normal kidneys, in 23.5% of kidneys with white spots, and in 48% of kidneys with large white spots, of 1 cm diameter or greater. The apparent (maximum) sensitivities of diagnostic procedures for detecting infection were as follows: MAT (at a titre of either 64 or 1024) 95%; IgM EIA 82%; culture 61%; presence of white spots 55%; IGSS 52%; presence of large white spots 30%; Warthin-Starry silver staining 20%. IGSS, Warthin-Starry staining and DNA hybridization all appeared to be highly specific. Of 22 kidney sections identified as positive by IGSS, 13 showed intact leptospires, and these kidneys were all culture-positive. Nine others showed leptospiral antigen in the kidney tubules but no intact leptospires. Only five of these kidneys were culture-positive.  相似文献   
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In this study, we explored the potential utility of the human‐focused FilmArray® Respiratory Panel for the diagnosis of a broad range of influenza viruses of veterinary concern as compared with the standard portfolio of recommended TaqMan®‐based diagnostic tests. In addition, we discuss some potential operational advantages associated with the use of such integrated sample extraction, amplification and analysis devices in the context of a future long‐term, dual‐role strategy for the detection of emergency diseases of both human and veterinary concern.  相似文献   
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AIM: To assess the effect of sedation and local anaesthesia (LA) at disbudding, and the addition of meloxicam or ketoprofen treatment, on weight gain in dairy calves following disbudding.

METHODS: Friesian-Jersey cross calves, from four dairy farms, were enrolled when 3–6 weeks old. All calves (n=271) were disbudded by veterinary personnel and randomly assigned to six groups: 136 were disbudded without sedation or LA, of which 31 received 20 mg meloxicam S/C and 75 received 150 mg ketoprofen I/M. A further 135 were disbudded with sedation (0.25 mg/kg xylazine I/M) and LA, of which 30 also received meloxicam and 75 received ketoprofen. Calves were weighed 3 days before, and 15 and 30 days after, disbudding (Day 0). Daily weight gain was analysed using mixed models and ANOVA.

RESULTS: Complete results were obtained from 263 calves. From Day ?3 to Day 15, the growth rate of calves disbudded without pain relief (0.53 (95% CI=0.47–0.60) kg/day) was less that of calves disbudded with some form of pain relief (0.65 (95% CI=0.62–0.68) kg/d; p=0.004). There was no difference between the effect of meloxicam or ketoprofen (p=1.00). An interaction between use of sedation and LA and additional non-steroidal anti-inflammatory drugs (NSAID) meant that NSAID treatment did not increase growth rates in calves disbudded with sedation and LA but did increase growth rates for calves disbudded without pain relief (p<0.05). From Day 16 to Day 30 there was no effect of NSAID treatment on growth rate, but calves receiving LA and sedation grew faster (0.74 (95% CI=0.69–0.80) kg/day) than calves disbudded without LA and sedation (0.66 (95% CI=0.61–0.71) kg/day; p=0.018). From Day ?3 to Day 30, calves disbudded with sedation and LA grew faster (0.71 (95%CI=0.64–0.77) kg/day) than calves disbudded without sedation and LA (0.60 (95% CI=0.55–0.65) kg/day; p=0.011). However, addition of NSAID to sedation and LA made no further difference to growth rates (p=0.69).

CONCLUSIONS: Dairy calves disbudded with no pain relief had slower growth rates than calves receiving pain relief. From Day 15 to 30 calves given no pain relief, or NSAID alone, grew more slowly than those receiving sedation and LA at disbudding. The addition of NSAID treatment to sedation and LA did not further increase growth rates.

CLINICAL RELEVANCE: This study adds to the evidence that pain management when disbudding is beneficial for calf productivity as well as calf welfare.  相似文献   
79.
Blood was collected from a group of ten sheep immediately after removal from pasture and thereafter at regular intervals for 50 hours whilst maintaining them without food but with adequate water. The samples were analysed for parameters normally examined as an aid to the diagnosis of zinc, copper, selenium, cobalt and iodine status. Serum vitamin B12 levels increased with time. Mean plasma zinc concentrations and mean serum concentrations of both T4 and fT4 followed significant parabolic trends. Maximum mean zinc levels (50 +/- 10% higher than initial values) were recorded after 30 hours. T4 and fT4 levels peaked at approximately 26 hours. Zinc levels at two hours were 20 +/- 5% lower than the initial values. Whole blood copper, selenium and glutathione peroxidase levels did not change significantly with time the largest differences were 11 +/- 6%, 5 +/- 4% and 10 +/- 8% respectively.  相似文献   
80.
Modifications of a radioassay method for the analysis of vitamin B12 using chicken serum as the binder are described. This obviates the need to use individual serum blanks to correct for non-specific binding in vitamin B12 assays of the sera and livers of sheep and cattle. Samples with high vitamin B12 levels can be diluted prior to assay without loss of linearity. Recoveries of added cyanocobalamin or hydroxocobalamin were better than 95% and results correlated significantly with those obtained using a microbiological assay (Poteriochromonas malhamensis). Sera and liver samples stored for four weeks at temperatures ranging from -20 degrees to 22 degrees showed no change in vitamin B12 levels. Withholding food from sheep for 44 hours led to a marked increase in serum vitamin B12. This effect was also evident in sheep eating a limited amount of cut grass. In sheep at pasture there was no evidence of a diurnal variation in serum vitamin B12 levels. Serum vitamin B12 levels in sheep at pasture were shown to be an unreliable indicator of liver vitamin B12.  相似文献   
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