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OBJECTIVE: To evaluate the effect of passive transfer status (determined from measurements of serum IgG concentration at 24 hours after parturition [sIgG-24]) on preweaning growth performance in dairy goat kids. DESIGN: Prospective observational study. ANIMALS: 20 healthy nursing dairy doe kids in a natural nonintensive breeding environment. PROCEDURES: For each kid, sIgG-24 was measured. Body weight was measured at birth and at the time of weaning 30 days (ie, 29 to 31 days) after birth; average daily gain from birth to day 30 and weight at day 30 were used as measures of preweaning growth performance. Regression analysis was used to evaluate associations between sIgG-24 and measures of preweaning growth performance. RESULTS: Mean +/- SD sIgG-24 was 31.7 +/- 10.3 mg/mL. Mean body weights at birth and weaning were 4.105 +/- 0.981 kg (9.031 +/- 2.158 lb) and 9.310 +/- 2.554 kg (20.482 +/- 5.619 lb), respectively; average daily gain was 0.174 +/- 0.072 kg/d (0.383 +/- 0.158 lb/d). No significant association was detected between sIgG-24 and birth weight. However, sIgG-24 was significantly associated with average daily gain (R(2) = 0.48) and weight at day 30 (R(2) = 0.56). Each increase in sIgG-24 of 1 mg/mL was associated with an increase in average daily gain of 0.005 kg/d (0.011 lb/d) and an increase in weight at day 30 of 0.185 kg (0.407 lb). CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that passive transfer status (determined as sIgG-24) was a significant source of variation in preweaning growth performance in dairy doe kids reared in this nonintensive breeding environment.  相似文献   
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Since summer 2010, numerous cases of Rabbit Haemorrhagic Disease (RHD) have been reported in north-western France both in rabbitries, affecting RHD-vaccinated rabbits, and in wild populations. We demonstrate that the aetiological agent was a lagovirus phylogenetically distinct from other lagoviruses and which presents a unique antigenic profile. Experimental results show that the disease differs from RHD in terms of disease duration, mortality rates, higher occurrence of subacute/chronic forms and that partial cross-protection occurs between RHDV and the new RHDV variant, designated RHDV2. These data support the hypothesis that RHDV2 is a new member of the Lagovirus genus. A molecular epidemiology study detected RHDV2 in France a few months before the first recorded cases and revealed that one year after its discovery it had spread throughout the country and had almost replaced RHDV strains. RHDV2 was detected in continental Italy in June 2011, then four months later in Sardinia.  相似文献   
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The effectiveness of the SS-SBR (Soil Slurry – Sequencing Batch Reactor) process for the remediation of soils contaminated by several organic pollutants has been evaluated. Experimental tests have been performed on two different soils, a spiked one and an industrial aged soil. The spiked soil, artificially contaminated, has been prepared trying to simulate the pollution of an industrial aged soil in terms of number and kind of contaminants. PAHs (Polycyclic Aromatic Hydrocarbons) and phenols degradation has been particularly investigated because they are considered persistent and recalcitrant. Concerning the spiked soil, removal efficiencies higher than 95% in 6 to 9 weeks have been found for all the pollutants, except for five-rings PAHs; however, these compounds were partly removed in 11 to 13 weeks. Good results have been achieved also for the industrial aged soil with a maximum removal of about 80% in 7–8 weeks. To enhance the pollutants degradation, trying to obtain a faster remediation, the biological treatment has been combined with a chemical oxidation with ozone. The best degradation effectiveness of the combined process has been obtained applying the ozonation after few days of the biological treatment. Therefore, a combined biological and chemical treatment allowed to markedly improve the remediation of contaminated soils.  相似文献   
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ABSTRACT: Susceptibility of sheep to scrapie, a transmissible spongiform encephalopathy of small ruminants, is strongly influenced by polymorphisms of the prion protein gene (PRNP). Breeding programs have been implemented to increase scrapie resistance in sheep populations; though desirable, a similar approach has not yet been applied in goats. European studies have now suggested that several polymorphisms can modulate scrapie susceptibility in goats: in particular, PRNP variant K222 has been associated with resistance in case-control studies in Italy, France and Greece. In this study we investigated the resistance conferred by this variant using a natural Italian goat scrapie isolate to intracerebrally challenge five goats carrying genotype Q/Q 222 (wild type) and five goats carrying genotype Q/K 222. By the end of the study, all five Q/Q 222 goats had died of scrapie after a mean incubation period of 19 months; one of the five Q/K 222 goats died after 24 months, while the other four were alive and apparently healthy up to the end of the study at 4.5 years post-challenge. All five of these animals were found to be scrapie negative. Statistical analysis showed that the probability of survival of the Q/K 222 goats versus the Q/Q 222 goats was significantly higher (p = 0.002). Our study shows that PRNP gene mutation K222 is strongly associated with resistance to classical scrapie also in experimental conditions, making it a potentially positive target for selection in the frame of breeding programs for resistance to classical scrapie in goats.  相似文献   
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Antioxidant compounds and antioxidant activity in "early potatoes"   总被引:1,自引:0,他引:1  
The antioxidant content and the antioxidant capacity of both hydrophilic and lipophilic antioxidant extracts from four "early potato" cultivars, grown in two different locations (Racale and Monteroni), were examined. There was a considerable variation in carotenoid content and weak differences in the ascorbic acid concentration of the examined cultivars of "early potato" and between the harvested locations. An increase in both methanol/water (8:2 v/v) and phosphate buffer soluble (PBS) free phenols (70%) and bound phenols (28%) in the extracts from the cultivars grown at Racale site was found and discussed. Examination of individual phenols revealed that chlorogenic acid and catechin were the major phenols present in potato tuber extracts; a moderate amount of caffeic acid and ferulic acid was also detected. The total equivalent antioxidant capacity (TEAC) was higher in the Racale extracts and a highly positive linear relationship ( R (2) = 0.8193) between TEAC values and total phenolic content was observed. The oxyradical scavenging capacity (TOSC) of methanol/water and PBS extracts of peel and whole potatoes against the reactive oxygen species (ROS) peroxyl radicals, peroxynitrite, and hydroxyl radicals was also analyzed. A highly significant linear correlation ( R (2) = 0.9613) between total antioxidant capacity (as a sum of peroxyl radicals + peroxynitrite) and total phenol content of methanol/water extracts was established. Moreover, proliferation of human mammalian cancer (MCF-7) cells was significantly inhibited in a dose-dependent manner after exposure to potato extracts. These data can be useful for "early potato" tuber characterization and suggest that the "early potato" has a potential as a dietary source of antioxidants.  相似文献   
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Recent studies have shown that propolis has on the oral cavity appreciable antibacterial, antifungal and antiviral actions, as well as anti-inflammatory, anaesthetic and cytostatic properties. In light of these studies, an assessment of the diffusion and permeation of caffeic acid phenetyl ester (CAPE) through porcine buccal mucosa was considered useful as a possible application in the stomatological field. To do so, a mucoadhesive topical gel was prepared to apply to the buccal mucosa. The gel was formulated in such a way as to improve the solubility of the propolis, conducting to an increase of the flux. The mucosal permeation of CAPE from the formulation was evaluated using Franz cells, with porcine buccal mucosa as septum between the formulation (donor compartment) and the receptor phase chamber. The diffusion through the membrane was determined by evaluating the amount of CAPE present in the receiving solution, the flux and the permeation coefficient (at the steady state) in the different formulations at set intervals. Qualitative and quantitative determinations were done by HPLC analysis. From the results, CAPE allowed a high permeability coefficient in comparison to the coefficient of other molecules, as expected from its physical-chemical structure. Moreover, the developed gel improved the CAPE flux approximately 35 times more with respect to an ethanol solution formulated at the same gel concentration. The developed gel was also tested in order to evaluate the mucoadhesive behaviour and comfort in vivo on 10 volunteers in a period of 8 h. The in vivo evaluation of mucoadhesive gel revealed adequate comfort and non-irritancy during the period of study and it was well accepted by the volunteers.  相似文献   
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