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21.
Surgical treatment of mitral stenosis (MS) usually consists of open mitral commissurotomy (MC) or percutaneous balloon MC, which require a cardiopulmonary bypass or transseptal approach, respectively. We describe here the first surgical management of congenital MS in a dog using a less invasive procedure, a surgical closed MC under direct echo guidance. A 5-year-old female Cairn terrier was referred for ascites, weakness, and marked exercise intolerance for 2 months, which was refractory to medical treatment. Diagnosis of severe MS associated with atrial fibrillation (AF) was confirmed by echo-Doppler examination and electrocardiography. Poor response to medical treatment suggested a corrective procedure on the valve was indicated. However, due to the cost and high mortality rate associated with cardiopulmonary bypass, a hybrid MC was recommended. A standard left intercostal thoracotomy was performed and three balloon valvuloplasty catheters of differing diameters were sequentially inserted through the left atrium under direct echo guidance. Transesophageal echocardiography revealed a 62% reduction in the pressure half-time compared to the pre-procedure. Thirteen months after surgery the dog is still doing well with resolution of ascites and a marked improvement of most echo-Doppler variables.  相似文献   
22.
A 4.5-yr-old male dromedary camel (Camelus dromedarius) was evaluated for a mass on the right side of the face. A complete blood count and blood chemistry revealed anemia and hypoproteinemia. Radiographs did not reveal bony involvement. The mass was resected and Pythium insidiosum was cultured. The camel was treated with an experimental immunotherapeutic vaccine and with sodium iodide and ceftiofur. The camel began to lose weight postoperatively and died 6 mo later. At necropsy, the camel was found to have gastritis of the third compartment of the stomach with intralesional hyphae of this oomycete pathogen.  相似文献   
23.
    
Diffuse ileal thickening and ileocecocolic lymphadenomegaly were observed during exploratory laparotomy in a 2-year-old male Japanese snow macaque (Macaca fuscata) that had flu-like signs and diarrhea. Cytologic examination of ileal biopsy imprints revealed many mature, mildly karyolytic neutrophils and fewer well-differentiated lymphocytes, eosinophils, macrophages, and plasma cells in a background containing amorphous, necrotic material. Tightly cohesive sheets of moderately pleomorphic epithelial cells also were seen. The cytologic diagnosis was chronic, active, mixed inflammation with atypical epithelial cells and necrosis. Histologically, the mucosal and crypt epithelium was moderately hyperplastic with a loss of goblet cells, increased mitoses, and frequent crypt abscesses. Within the lamina propria and extending into the submucosa was a marked neutrophilic infiltrate, with low numbers of lymphocytes, histiocytes, plasma cells, and eosinophils. The histologic diagnosis was chronic, diffuse, marked suppurative and lymphocytic ileitis. Warthin-Starry silver staining of the ileal biopsy and imprint specimens demonstrated numerous pleomorphic, curved bacilli consistent with Lawsonia intracellularis. Polymerase chain reaction (PCR) and immunohistochemistry confirmed the identity of the infectious agent. L intracellularis infection may be underdiagnosed because silver stain is required to visualize the organism with light microscopy and because the pathognomonic crypt hyperplasia may be complicated by secondary pathologic changes. Application of silver stain to cytologic specimens should be considered when distal intestinal lesions associated with hyperplastic epithelium, with or without inflammation, hemorrhage, or necrosis, are identified in animals with clinical signs of enteritis, especially in frequently affected species or in stressed or young animals.  相似文献   
24.
    
Elevated levels of Al in soil solution may be toxic to plants. The activity of monomeric inorganic Al species is the best measure of the phytotoxic fraction. Decreasing soil pH increases soil solution Al exponentially as the pH falls below 4.5. In the presence of organic matter and organic acids the availability of A1 is reduced, due to complexation. The Al concentration is also dependent on dominant clay mineral and clay content. Symptoms of Al toxicity usually first appear in the roots becoming structurally and functionally damaged and inefficient in absorbing water and nutrients. This might be due to disturbance of mitosis and changed permeability of the root membranes. Aluminium also affects DNA replication, protein synthesis, and activity of some enzymes. Symptoms on shoots usually develop at a later stage of Al poisoning. There is an antagonism between the macronutrients P, Ca, Mg, and K on the one hand, and Al on the other. Aluminium may induce deficiency of mineral nutrients and high nutrient concentrations reduce al toxicity. There is considerable variation in Al tolerance between species and between varieties of the same species. Several mechanisms for Al tolerance are suggested. Tolerant plants may possess an active exclusion mechanism or may be able to inactivate Al within their tissues. pH increases induced by the plant in the rhizosphere, exudation of chelating agents, a low C.E.C. in the roots and an ability to withstand or compensate Al induced nutrient deficiency are other possible tolerance mechanisms.  相似文献   
25.
    
Harpacticoid copepods are being considered as alternative candidates for live feed in aquaculture, but their benthic affinity may pose problems for pelagic fish larvae. We compared the swimming behaviour and feeding incidence of herring larvae (Clupea harengus) in the presence of harpacticoid copepods (Tachidius discipes) and rotifers (Brachionus plicatilis). Additionally, we provided T. discipes via a floating sieve to improve the prey availability. The comparison was performed at 5 and 10 days post hatch (dph) via 2D‐video observations. Quantitative analyses of larval trajectories allowed the estimation of feeding behaviour through a series of indicators: swimming speed, straightness of trajectories, turning angles and swimming activities (break, sink, slow, normal, fast). The outcomes highlighted that the prey type had no significant effect on swimming speed or straightness of the swimming path. However, at 10 dph directly copepod‐fed larvae spent less time in slow but more time in the normal swimming‐state than rotifer‐fed larvae and larvae fed with Tachidius via sieve. This suggests higher energy expenditure of directly copepod‐fed larvae. Moreover, the feeding incidence was higher in larvae fed with Tachidius via sieve than directly Tachidius‐fed larvae. Thus, providing harpacticoid copepods via a floating sieve can improve the rearing of marine fish larvae.  相似文献   
26.
Bluetongue (BT) can cause severe livestock losses and large direct and indirect costs for farmers. To propose targeted control strategies as alternative to massive vaccination, there is a need to better understand how BT virus spread in space and time according to local characteristics of host and vector populations. Our objective was to assess, using a modelling approach, how spatiotemporal heterogeneities in abundance and distribution of hosts and vectors impact the occurrence and amplitude of local and regional BT epidemics. We built a reaction–diffusion model accounting for the seasonality in vector abundance and the active dispersal of vectors. Because of the scale chosen, and movement restrictions imposed during epidemics, host movements and wind-induced passive vector movements were neglected. Four levels of complexity were addressed using a theoretical approach, from a homogeneous to a heterogeneous environment in abundance and distribution of hosts and vectors. These scenarios were illustrated using data on abundance and distribution of hosts and vectors in a real geographical area. We have shown that local epidemics can occur earlier and be larger in scale far from the primary case rather than close to it. Moreover, spatial heterogeneities in hosts and vectors delay the epidemic peak and decrease the infection prevalence. The results obtained on a real area confirmed those obtained on a theoretical domain. Although developed to represent BTV spatiotemporal spread, our model can be used to study other vector-borne diseases of animals with a local to regional spread by vector diffusion.  相似文献   
27.
28.
    
  1. Anthropogenic changes in the marine environment and global climate change have led to population declines in several seabird species worldwide. Rockhopper penguins (Eudyptes chrysocome and Eudyptes moseleyi) have experienced a dramatic population decline, potentially linked to increasing sea surface temperatures (SST). Among Southern Ocean diving seabirds, rockhopper penguins typically occupy a low trophic level, and might therefore be expected to mirror climate‐driven bottom‐up changes to the food web sensitively and on a short time scale.
  2. Using passive integrated transponders, survival rates of adults in a colony of southern rockhopper penguins (E. chrysocome) on the Falkland Islands were monitored over five consecutive years. Mean annual survival rates were in the range 84 to 96%.
  3. These values are high compared with other crested penguin species and reflect the generally good conditions during the study period, when low SST prevailed. However, survival rates were lower in 2010, corresponding to very cold conditions. Curve fits showed a best‐fit quadratic relationship between average SST anomaly and survival rates for the present data, as well as for a data set including two additional years from a different study at Staten Island.
  4. Results of this study suggest that rockhopper penguins survive best at SSTs that are lower than the average of the last four decades. In accordance with previously observed rockhopper penguin population declines, the present data suggest that rockhopper penguins are highly sensitive to changes in SST and their effects on the food web, a worrying perspective in times of global climate change. It seems likely that these changes could, in the long term, also affect population trends of other seabird species with similar ecological preferences.
  5. The most promising conservation approach should aim at enhancing ecosystem resilience, mainly by reducing industrial fishing and oil exploitation. This would allow the currently over‐exploited fish and squid stocks to recover, offering larger food resources to seabirds and other vertebrate species.
Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
29.
The performances of the GC-MS determination of suspected allergens in fragrance concentrates have been investigated. The limit of quantification was experimentally determined (10 mg/L), and the variability was investigated for three different data treatment strategies: (1) two columns and three quantification ions; (2) two columns and one quantification ion; and (3) one column and three quantification ions. The first strategy best minimizes the risk of determination bias due to coelutions. This risk was evaluated by calculating the probability of coeluting a suspected allergen with perfume constituents exhibiting ions in common. For hydroxycitronellal, when using a two-column strategy, this may statistically occur more than once every 36 analyses for one ion or once every 144 analyses for three ions in common.  相似文献   
30.
    
Whole wheat pasta offers improved nutritional value compared with regular pasta but lacks appeal to many consumers owing to its negative organoleptic properties, such as texture and taste. Various approaches have been studied to improve these properties in whole wheat products. Optimizing bran particle size showed its potential in noodles, but studies of its effects in pasta are scarce. Therefore, we produced spaghetti enriched with bran fractions similar in chemical composition but with varying median particle sizes of 90, 160, 370, and 440 µm. The effect of bran particles and their median size on dried and cooked pasta was studied by light microscopy and three‐dimensional magnetic resonance imaging. In general, bran particle size did not influence the macrostructure in cooked spaghetti. However, larger bran particles created a more heterogeneous microstructure in contrast to smaller particles and affected starch granule swelling. Sensory analysis indicated a preference for pasta containing smaller particles. Our results give new insight into the microstructural features responsible for the negative consumer appeal, and they could be used to guide future efforts in designing improved pasta formulations.  相似文献   
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