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61.
An adult, male, captive lined seahorse (Hippocampus erectus) was presented with weight loss, anorexia, and brood pouch distention. Initial treatments included manual expression of the brood pouch followed by saline flushes and enrofloxacin infusions. Radiographs and physical examination identified a nodular swelling in the brood pouch wall. The mass was excised, but the seahorse died. Necropsy and histopathology revealed a malignant mesenchymal tumor with a collagenous stroma, and a brood pouch fibrosarcoma was diagnosed.  相似文献   
62.
Background: As veterinary medicine has become more sophisticated, with greater numbers of veterinary patients receiving intensive care, more patients with an acute respiratory distress (ARDS)‐like syndrome have been recognized. Methods: A consensus definition meeting was held for the purpose of developing veterinary‐specific definitions for acute lung injury (ALI) and ARDS. Results/conclusions: Three clinically based definitions for acute lung injury and acute respiratory distress‐like syndromes occurring in veterinary patients were described. Neonatal equine respiratory distress syndrome (NERDS) was defined separately due to the specific requirement for primary developmental surfactant dysfunction and lack of an inflammatory component. Five diagnostic criteria categories were established for Veterinary ALI/ARDS (Vet ALI/ARDS) with 4 required and a fifth highly recommended criteria. A strong consensus was reached that onset of respiratory distress must have been acute and that known risk factors must be present. Additional criteria included evidence of pulmonary capillary leak with no evidence of increased pulmonary capillary pressure, evidence of inefficient gas exchange and, finally, evidence of inflammation. Some features of ALI/ARDS in the neonatal horse were recognized as unique, therefore, equine neonatal ALI/ARDS (EqNALI/EqNARDS) was similarly defined but with a graded gas exchange inefficiency table to allow for normal developmental changes in gas exchange. Use of these definitions in planning prospective studies of these problems in veterinary patients should allow for more direct comparisons of studies and clinical trials, with a larger goal of improving outcome in veterinary patients.  相似文献   
63.
Two species of Rhinoestrus (i.e. Rhinoestrus purpureus (Brauer) and Rhinoestrus usbekistanicus Gan) cause nasal myiasis in horses, donkeys and zebras. In the past 15 years myiasis caused by R. purpureus has been reported in Egypt and by R. usbekistanicus in Senegal and Niger, both in horses and in donkeys. With the aim to investigate the presence of this myiasis in autochthonous horses and donkeys from southern Italy and to study the seasonal trend of larval infection, 212 native horses were necropsied in two slaughterhouses in the Apulia region (site A) from January to November 2003, and 120 native horses and two donkeys in one slaughterhouse in Sicily (site B) from January to October 2003. Thirteen of 212 and 5 of 120 horses examined from sites A and B, respectively, were infected by nasal bot fly larvae. Both donkeys examined were positive. Two hundred and thirteen larvae, representing all stages, were collected from the throat region, the turbinates and beyond the lamina cribrosa of the ethmoid bone, in the cerebral cavity. Third larval stages were retrieved from April to September with the highest mean burden in site A in May and in July in site B. The simultaneous presence all three larval stages at site B suggests the existence of two or more overlapping generations. Larvae were identified on the basis of peritreme structures and arrangement of the spines on the dorsal surface of the third segment. Some L3 collected from sites A and B presented morphological characteristics of both R. usbekistanicus and R. purpureus. The presence of mixed features on the L3 of Rhinoestrus collected from the same animals may be explained by the existence of a single species of Rhinoestrus presenting different morphotypes or of two species of Rhinoestrus which are both present in southern Italy since this area is midway between eastern and African countries where these two species have been reported.  相似文献   
64.
Ceccarelli  Salvatore 《Euphytica》1994,77(3):205-219
Summary Breeding has been very successful in generating cultivars that in favorable environments, and together with large use of fertilizer and chemical control of weeds, pest and diseases, have increased agricultural production several fold. Today the environmental impact of high input agriculture in more favorable environments causes growing concern. By contrast, the impact of breeding in marginal environments has been elusive. The paper discusses evidence showing that the use of breeding principles developed for, and successfully applied, in favorable environments may be the main reason for the lack of breeding progress in marginal environments. Very little breeding work has actually been done in marginal environments, although the theory of correlated responses to selection indicates that selection conducted in good environments or in well-managed experiment stations is not expected to be very efficient when genotype by environment interactions of a cross-over type exist. The assumptions that heritability is higher under good conditions and that there is a carry-over effect of high yield potential are not supported by experimental evidence. If the target environment is below the cross-over point, selection has to be conducted for specific adaptation to that environment. The concept of wide adaptation has more a geographical than an environmental meaning, and it reduces genetic diversity and increases genetic vulnerability. Eventually the issue of genetic heterogeneity versus genetic uniformity is discussed in relation to specific adaptation to marginal environments.  相似文献   
65.
Adaptation to low/high input cultivation   总被引:1,自引:0,他引:1  
Summary Many aeas of world, particular those where agriculture is largely practiced by resource-poor farmers with little or no use of external inputs, have not benefitted from the spectacular yield increases achieved by the combination of modern breeding technologies and use of inputs. The paper argues that because breeding is mostly conducted in presence of high inputs, it has systematically missed the opportunity to exploit genetic differences at low levels of inputs. Many studies show that these differences do exist, particularly in the case of fertilizers, and that these differences can only be identified is selection is conducted under the target level of inputs. Although this was predicted by theory more than 40 years ago, and has been supported by a large body of experimental data, very few breeders select in sub-optimal or stress conditions. The most common justification is the high environmental variation, and hence the lower heritability expected in low input conditions. While this is not supported by experimental evidence, the paper shows that in the case of a typical crop grown in low-input and climatically marginal conditions such as barley, genetic gains are possible by using locally adapted germplasm and by selecting in the target environment. Similar conclusions, in relation to the use of a low-input selection environment, have been reached recently in maize. It is concluded that the best avenue to a sustainable increase of agricultural production in low-input agricultural systems is through locally based breeding programs.  相似文献   
66.
67.
The topical anti-inflammatory, free radical scavenging and antifungal activities of essential oils and extracts of Commiphora erythraea (Ehrenb.) Engl. resin were investigated. The hexane extract significantly inhibited oedema when applied topically in Croton oil-induced ear oedema assay in mice. The same extract showed antioxidant activity in DPPH radical scavenging assay. A bioguided separation of the hexane extract led to the isolation of furanosesquiterpenoids 1 and 2 that showed a weak antifungal activity, while compounds 3-5 resulted to be antioxidant (EC50 4.28, 2.56 and 1.08 mg/mL, respectively) and anti-inflammatory (30, 26 and 32% oedema reduction, respectively).  相似文献   
68.

Purpose  

The evaluation of long-term heavy metal concentrations in the Gulf of Palermo (Italy) has been carried out in order to investigate how changes of pollution levels in the last 50 years can be reflected in marine sediments. Measurements of Cr, Cu, Hg, Pb, and Zn concentrations were performed on dated fractions of a sediment core. Time series analysis has allowed to obtain information on the chronology of the heavy metal pollution of the area and to identify seasonal components and trends.  相似文献   
69.
This study was carried out to identify superior barley genotypes for the rainfed areas of western Iran using a participatory varietal selection (PVS) approach. Three field experiments were conducted in two randomly selected farmers’ fields and in one rainfed research station in the 2006–07 cropping season with 69 genotypes (including one local and one improved check). Several univariate and multivariate methods were used to analyze qualitative (farmers’ scores) and quantitative (grain yield) data. Individual farmers’ scores in each village were positively correlated, indicating that the farmers tended to discriminate genotypes in similar fashion, although the genotypes actually selected by farmers were different in the two villages. In recent years, a greater number of farmers in western Iran preferred the improved variety (Sararood-1) over the local barley (Mahali), while in this project the farmers preferred the new genotypes over the two checks. This was also verified by the quantitative data showing that the checks were outyielded by the new genotypes. Farmers were efficient in identifying the best genotypes for their specific environment, as shown by biplot analysis, indicating their competence in selection. The genotypes selected by the breeder and farmers were almost similar but some differences existed. In conclusion, PVS is a powerful way to involve farmers for selecting and testing new cultivars that are adapted to their needs, systems and environments.  相似文献   
70.
After recent isolations of Brucella sp. from pinnipeds and cetaceans, a survey was initiated to investigate the prevalence of Brucella sp. infections and serologic evidence of exposure in marine mammals stranded along the coasts of Connecticut and Rhode Island. One hundred and nineteen serum samples from four species of cetaceans and four species of pinnipeds were collected from 1985 to 2000 and tested for antibodies to Brucella sp. using the brucellosis card test, buffered acidified plate antigen test, and rivanol test. In addition, 20 of these were necropsied between 1998 and 2000, with lymphoid and visceral tissues cultured for Brucella sp. Three of 21 (14%) harbor seals (Phoca vitulina) and four of 53 (8%) harp seals (Phoca groenlandica) were seropositive. Brucella sp. was isolated from two of four (50%) harbor seals and three of nine (33%) harp seals. Of the five animals with positive cultures, two were seropositive and three seronegative. Brucella sp. was most frequently cultured from the lung and axillary, inguinal, and prescapular lymph nodes. Tissues from which Brucella sp. was isolated showed no gross or histopathologic changes. These results indicate that marine mammals stranded along the coast of southern New England can be exposed to and infected with Brucella sp.  相似文献   
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