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61.
Monoclonal Gammopathy in a Dog With Visceral Leishmaniasis   总被引:1,自引:0,他引:1  
One dog with visceral leishmaniasis associated with monoclonal gammopathy is described. Most dogs with visceral leishmaniasis present with hyperproteinemia due to a polyclonal gammopathy, but the possibility of monoclonal gammopathy must be considered. Because dogs accompany their owners when they travel, the diagnosis of leishmaniasis should be considered if an animal with monoclonal gammopathy has visited an area where the disease is endemic. The observation of Leishmania in the macrophages of a bone marrow, lymph node smear, or skin biopsy specimen is diagnostic.  相似文献   
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Thymolipomas are rare benign thymic neoplasms recognised in humans, composed of mature adipose tissue and thymic tissue. An 8-year-old male domestic shorthair cat presented with anorexia, lethargy and vomiting secondary to the development of a thoracic effusion and an anterior mediastinal tumoral mass with fatty appearance. Histologically, the mass consisted of adipose tissue containing numerous cords and nests of cortical and medullary thymic tissue. No signs of thymic epithelial or lymphoid neoplastic proliferation were detected. The findings in this case are remarkably similar to the macroscopic and histological features of thymolipoma in humans.  相似文献   
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Colocasia esculenta (L.) Shott, commonly called taro, is an ancient species selected for its edible tuber. Its huge "elephant ear" like leaves are also consumed in sauces and stews or as soups. Forty-one phenolic metabolites (11 hydroxycinnamic acid derivatives and 30 glycosylated flavonoids) were identified by high-performance liquid chromatography-diode array detection-electrospray ionization/mass spectrometry (HPLC-DAD-ESI/MS(n)) in the leaves of two C. esculenta varieties cultivated in Azores Islands. To our knowledge, 34 of the 41 phenolic compounds are being reported for the first time in this species. Phenolics quantification was achieved by an HPLC-DAD accurate and sensitive validated method. Although the qualitative profile of the two varieties is quite similar, quantitative differences were observed between them. "Giant white" and "red" varieties (local denomination) contain, respectively, ca. 14 and 21% of phenolic acids, 37 and 28% of flavones mono-C-glycosides, 42 and 43% of flavones di-C-glycosides, 3 and 4% of flavones mono-C-(O-glycosyl)glycosides, and both of them ca. 2% of flavones di-C-(O-glycosyl)glycosides and 2% of flavones-O-glycosides. Luteolin-6-C-hexoside was the compound present in higher amounts in both varieties. The established phenolic profile is an added value for the authenticity and quality control of C. esculenta and may be useful in the discrimination of its varieties.  相似文献   
66.
Eucalyptus globulus, a non-native species, is currently the most abundant forest species in Portugal. This economically important forest tree is exploited mainly for the production of pulp for the paper industry. The community of Botryosphaeriaceae species occurring on diseased and healthy E. globulus trees was studied on plantations throughout the country. Nine species from three different genera were identified, namely Botryosphaeria (B. dothidea), Diplodia (D. corticola and D. seriata) and Neofusicoccum (N. australe, N. algeriense, N. eucalyptorum, N. kwambonambiense, N. parvum and Neofusicoccum sp.). Of these, N. algeriense, D. corticola and D. seriata are reported for the first time on E. globulus, while N. algeriense, N. eucalyptorum and N. kwambonambiense correspond to first reports in Portugal. The genus Neofusicoccum was clearly dominant with N. australe and N. eucalyptorum being the most abundant species on both diseased and healthy trees. In artificial inoculation trials representative isolates from all nine species were shown to be pathogenic to E. globulus but there were marked differences in aggressiveness between them. Thus, D. corticola and N. kwambonambiense were the most aggressive while B. dothidea and D. seriata were the least aggressive of the species studied.  相似文献   
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The development of the basidiomycete Moniliophthora perniciosa in resistant and susceptible Theobroma cacao genotypes was analysed. The infection process leading to broom formation in shoot apexes was characterized by studying the kinetics of basidiospore germination, mode of penetration and colonization of the pathogen. Both resistant and susceptible cacao genotypes were inoculated with M. perniciosa and kept in the greenhouse for 90 days, explants were collected, treated for histological studies and meristematic tissues were observed by electron and light microscopy. Variation in the kinetics of germination between the cacao genotypes was detected 4 h after inoculation. The fungal penetration occurred through the star‐shaped trichome base, natural openings on the cuticular surface and stomata. Host responses between genotypes were found to be different. Compared with non‐infected plants, the swelling of all the stem tissues was evident at 60 days after inoculation. In the susceptible genotype, typical symptoms developed and fungal colonization was more intense than in resistant genotypes, which showed little or no fungal colonization. The investigations reported herein provide an important step in understanding the pattern of pre‐ and post‐penetration events of M. perniciosa in cacao genotypes with different levels of resistance to this disease.  相似文献   
69.
Spatial and temporal changes in community structure of soil organisms may result from a myriad of processes operating at a hierarchy of spatial scales, from small-scale habitat conditions to species movements among patches and large-sale landscape features. To disentangle the relative importance of spatial and environmental factors at different scales (plot, patch and landscape), we analyzed changes in Collembola community structure along a gradient of forest fragmentation, testing predictions of the Hierarchical Patch Dynamics Paradigm (HPDP) in different European biogeographic regions (Boreal, Continental, Atlantic, Mediterranean, Alpine). Using variance partitioning methods, based on partial CCAs, we observed that the independent effect of environmental processes was significantly explaining Collembola community variance in all regions, while the relative effect of spatial variables was not significant, due to the observed high levels of landscape heterogeneity along the gradient. Environmental factors at the patch and plot scales were generally significant and explained the larger part of community changes. Landscape variables were not significant across all study sites. Yet, at the landscape level, an increase in forest habitat and proximity of forest patches were showed to have an indirect influence on local community changes, by influencing microhabitat heterogeneity at lower spatial scales in all studied regions. In line with HPDP, large-scale landscape features influenced spatio-temporal changes in soil fauna communities by constraining small-scale environmental processes. In turn, these provided mechanistic understanding for diversity patterns operating at the patch scale, via shifts in community weighted mean of Collembola life-forms occurring in local communities along the fragmentation gradient.  相似文献   
70.
The technical efficiency of randomly sampled pangasius farms in the Mekong Delta of Vietnam was estimated using data envelopment analysis, and factors affecting technical and scale efficiency were examined with bootstrap truncated regression. The mean technical efficiency score assuming variable returns to scale was 0.84. The technical efficiency of downstream farmers was higher due to lower energy costs and stocking once a year. Most of the up‐ and midstream farms needed to pump water and stocked at least three times in 2 yr. Regression analysis showed a positive effect on technical efficiency of the farmers' education level and having experienced climate change impact through flooding or salinity intrusion in the past. Farms affected by salinity intrusion had a lower scale efficiency as they reduce stocking frequency and rate. In general, reducing fish mortality and the cost of inputs, increasing scale of operation, and being trained, using appropriate methods, in management strategies may improve technical efficiency.  相似文献   
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