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51.
A 6-year-old intact female Labrador Retriever had diabetes mellitus, which had been difficult to control with insulin. The dog also had a solid ductal mammary carcinoma with very rapid growth, which was temporally related to onset of hypoglycemia. Eight months after initial diagnosis of diabetes, the dog had a hypoglycemic crisis. Insulin administration was stopped and serum glucose concentration returned to normal. Three months after discontinuing insulin, another hypoglycemic crisis occurred. During subsequent months, serum glucose concentrations remained at life-threatening levels (1.64-2.12 mmol/L, reference interval 4.44-6.66 mmol/L) simultaneously with an increase in the size of the mammary tumor, which reached a diameter of about 16 cm. At the time of surgery for removal of the tumor serum glucose concentration was 2.20 mmol/L and was then monitored every 3 hours after excision of the tumor. The glucose concentration continued to rise and reached 9.99 mmol/L 12 hours after the removal of the mammary tumor. Immunohistochemical staining demonstrated expression of insulin growth factor-2 by tumor cells, which apparently had caused the hypoglycemia during tumor growth even in a diabetic dog. Hyperglycemia associated with diabetes was pronounced after excision of the tumor and had been masked by the paraneoplastic effect of the tumor.  相似文献   
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Rhizopycnis vagum is a recently described coelomycete known to belong to the complex of root rot pathogens contributing to vine decline of cucurbits in several parts of the world. However, the fungus has also been reported to infect tomato, and as an endophytic associate of mycorrhizal roots of wild, asymptomatic Pinus halepensis and Rosmarinus officinalis plants in Italy. To accelerate epidemiological and ecological investigations on this fungus, a PCR primer pair was developed. Primers Rv1-F and Rv1-R were designed, based on alignment of internal transcribed spacer (ITS) sequences (ITS1-5.8S-ITS2), which amplified a 396-bp fragment from all R. vagum isolates tested, including isolates pathogenic to melons and endophytic isolates from mycorrhizae. Specificity of the primer pair was verified both in silico (BLAST searches using each primer string as a query) and in PCR assays, where the primers failed to amplify DNA from any isolate of fungi taxonomically related to R. vagum (e.g. Massarina walkeri and Stagonospora spp.) and other vine decline and common soilborne pathogens (e.g. Monasporascus cannonballus, Acremonium cucurbitacearum, Fusarium spp. and Rhizoctonia solani). Under optimum conditions, detectable amplification of the specific sequence required 0.05 pg of target DNA. Amplification of the expected 369-bp fragment was also obtained from DNA root extracts of nearly asymptomatic Cucumis melo plants inoculated with R. vagum under greenhouse conditions.  相似文献   
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To compare the phenolic responses under oxidative stressors, plants of two Italian cultivars of durum wheat (Claudio and Mongibello) were (a) exposed to ozone (O3) (80 ppb, 5 hr/day for 70 consecutive days), with the aim to investigate the changes of phenolic compound contents in their leaves, or (b) flooded (seven consecutive days). Plants showed O3-induced visible injury, but their photosynthetic performance was not affected by the pollutant. Specifically, Claudio showed a higher O3 tolerance than Mongibello. The major value of the present study is undoubtedly the pioneering investigation of phenolic metabolism of durum wheat under O3. We identified 12 foliar phenolic compounds in all leaf samples (i.e. controls, exposed to O3 and flooded): ten phenolic acids, a flavanol (catechin hydrate) and a phenolic aldehyde (syringaldehyde). Overall, O3 exposure resulted in accumulations of phenolic compounds, especially in Claudio. These responses can be likely considered a fine-regulated repair process that equipped Claudio stressed plants with an antioxidant system capable of scavenging oxidative stress. Different phenolic variations were found in flooded plants, suggesting that phenolic response to environmental constraints is stress specific. Our study confirms that investigations and characterization of specific phenolic profiles of crop cultivars under oxidative stress may be helpful in breeding programmes.  相似文献   
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Two sandstone-derived soils under pure stands of silver fir (Abies alba Mill.) and European beech (Fagus sylvatica L.) were studied to determine if the fine earth (<2 mm material) and two size-classes of porous rock fragments (>2 mm material) supported different microbial communities. Samples from three soil horizons (A, Bw, and BC) were analysed under both optical and scanning electron microscopes. Small stones (2-10 mm in average diameter) appeared more altered than larger ones (40-60 mm) and the effects of weathering became more obvious with shallower depth. In both soils, numerous hyphae and other living forms were observed on the surface of the stones from the A and Bw horizons; this contrasted with the stones from the BC horizon, which showed little or no colonisation. The microbial community of each fraction was characterised using Biolog-Community Level Physiological Profiles (CLPP) and phospholipid fatty acid analyses (PLFA) for samples in the A and B horizons. Significant potential microbial activity (C source utilisation) was associated with rock fragments, from the A horizon and, to a lesser extent, the B, although this was lower than for the equivalent fine earth fraction. The microbial colonisation of the stones appeared inversely related with their size and sampling depth. The PLFA analysis showed not only quantitative differences in the microbial biomass between horizons and size-fractions but also highlighted that the communities differed between soils, horizons (for the sole beech soil) and fractions. These findings demonstrate that by considering rock fragments as a microbiologically inert fraction and discarding them before analysis, as usually is done, can lead to an incomplete picture of both the total amount and, perhaps more importantly, the structure of soil microbial community.  相似文献   
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Probiotics are microorganisms that are added to food to exert beneficial effects on the host. Aim of the present study was the in vitro and in vivo evaluation of the effect of Lactobacillus animalis LA4 (isolated from the faeces of a healthy adult dog) on composition and metabolism of dog intestinal microflora. When added to dog faecal cultures, LA4 reduced enterococci and increased lactobacilli counts throughout the study, whereas C. perfringens counts were significantly reduced at 24 h. After 8 h of incubation, LA4 reduced ammonia and increased lactic acid concentrations. For the in vivo study, nine adult dogs received the freeze-dried preparation of L. animalis LA4 for 10 days. On day 11, faecal lactobacilli were higher than at trial start (6.99 log CFU/g versus 3.35 log CFU/g of faeces) and faecal enterococci showed a trend towards a numerical reduction (P = 0.08). L. animalis LA4 was recovered in all faecal samples collected on day 11 and in four samples at day 15. The present results show that LA4 was able to survive gastrointestinal passage and transitorily colonize the dog intestine where, based on the in vitro results, it could positively influence composition and metabolism of the intestinal microflora. These results suggest that L. animalis LA4 can be considered as a potential probiotic for dogs.  相似文献   
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Orange juice is a source of antioxidants that might afford in vivo protection from oxidative stress. To test this hypothesis, we carried out a human intervention study with blood orange juice containing high amounts of vitamin C, anthocyanins, and carotenoids. Sixteen healthy female volunteers were enrolled in a crossover study and were given 600 mL/day of blood orange juice or a diet without juice for 21 days. Before and after each intervention period, plasma vitamin C, cyanidin-3-glucoside, and carotenoids were quantified. Furthermore, plasma antioxidant capacity, malondialdehyde concentration in plasma, 11-dehydrotromboxane B(2) urinary excretion, and lymphocyte DNA damage were evaluated as biomarkers of oxidative stress. Blood orange juice consumption determined a significant increase in plasma vitamin C, cyanidin-3-glucoside, beta-cryptoxanthin, and zeaxanthin. Also, lymphocyte DNA resistance to oxidative stress was improved whereas no effect was observed on the other markers that we analyzed. In turn, these results suggest that blood orange juice is a bioavailable source of antioxidants, which might moderately improve the antioxidant defense system; however, the long-term effects of its consumption are to be further investigated.  相似文献   
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The aim of this retrospective, cross‐sectional, study was to evaluate clinical findings and outcomes for different ultrasonographic patterns of hepatic emphysema in dogs and cats. Dogs and cats with an ultrasonographic diagnosis of hepatic emphysema and a known outcome, from January 2010 to January 2018, were enrolled. The following data were recorded from medical and ultrasonographic records: ultrasonographic patterns of hepatic emphysema (parenchymal, portal venous, biliary), clinical signs, laboratory findings, and outcomes (favorable, poor). A total of 33 dogs and four cats met the inclusion criteria. Among these, 23 cases were classified as hepatic portal venous gas, 10 as parenchymal emphysema, and four as biliary emphysema. Clinical diagnosis categories were as follows: infection/sepsis (9), gastro‐intestinal disease (9), iatrogenic (9), trauma (5), and liver neoplasia (5). An increase in serum liver enzymes was significantly associated with parenchymal emphysema (P = .03). Other clinical and laboratory findings were not associated with the type of hepatic emphysema. Hepatic portal venous gas was mostly transient in patients with ultrasonographic follow‐up. The overall mortality was 40.5%. A significant difference was found between mortality by portal venous gas (21.7%) and mortality by parenchymal emphysema (90%) (P = .003). In conclusion, the ultrasonographic differentiation of hepatic emphysema between hepatic portal venous gas and parenchymal emphysema may be important for the prognosis of hepatic emphysema. The presence of parenchymal emphysema may be a poor prognostic indicator, while hepatic portal venous gas may be more benign. However, ultrasound findings should be carefully evaluated in the context of clinical findings.  相似文献   
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Integrative taxonomy, a multi‐disciplinary approach adding modern techniques to traditional morphology‐based methods (e.g. molecular and morphological criteria), can play an important role in bioinvasion research to identify introduced taxa, discover pathways of introduction and inform authorities to control and prevent future introductions. The present study is the first on introduced populations of Callosciurus, Asiatic tree squirrels, known as potentially invasive species in Europe (Italy, Belgium and France). We combined molecular (mitochondrial DNA markers: CoxI, D‐loop) and morphometric analysis on skulls, comparing them to the widest morphological and molecular datasets ever assembled for Callosciurus. Squirrels collected in Italy and Belgium share the same haplotypes and skull characteristics, but are conspicuously different from the French population in Antibes. Genetic data revealed close similarity between French squirrels and Pallas's squirrels, Callosciurus erythraeus, from Taiwan, China. Italian and Belgian squirrels formed an independent taxonomic lineage in genetic analyses, whose taxonomic rank needs further investigation. The morphological and morphometric characteristics of these 2 populations are, however, similar to known specimens assigned to Callosciurus erythraeus. These results may indicate a common origin for the populations found in Belgium and Italy. In contrast, French specimens suggest an independent introduction event of squirrels originating from Asia.  相似文献   
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