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181.
During 1972, 333 fluff samples were tested from 13 Queensland hatcheries and assessed according to the English standards for total count, coliforms and fungi. They were also assessed as being "standard" or "substandard", using a combination of the criteria of the English system. All hatcheries had at least 2 substandard samples and all the samples from 2 hatcheries were substandard.  相似文献   
182.
Introduction:  We evaluated the totally implantable subcutaneous vascular access port (VAP) in 16 cancer patients undergoing intermittent chemotherapy for more than 30 months.
Methods:  Ports were surgically placed (The CompanionPort, Norfolk Vet Products, Skokie, Illinois 60076) in the jugular vein of 12 dogs and 4 cats between 1/2002 and 7/2004. Body weight determined polyurethane catheter size (4, 5, 7 fr.). The polysulfone port, surrounded by titanium, was anchored to subcutaneous tissue in the dorsolateral neck and confirmed with C‐arm fluoroscopy. All blood samples were obtained via VAP. Nine anticancer agents, other medications, crystalloids/colloids, and whole blood were administered. Ports were flushed every 4–5 weeks with heparinized saline solution (100 IU/ml). Removed catheters were submitted for bacteriology.
Results:  Seven of 16 animals are still alive. VAP were used for 1.5 to more than 30 months with 4–60 injections/port. Catheter tips were visualized from the left atrium distally into the caudal vena cava. Adverse events included post‐operative subcutaneous bruising and/or hematoma (4/16), difficult aspiration (4/16), catheter malposition (1/16), positional flushing (1/16), and occlusion requiring replacement (1/16). No thrombus formation or extravasation was evident. Bacterial colonization without signs of septicemia was observed in 3/4 catheters.
Conclusions:  VAP are an effective way of achieving long‐term venous access in the dog and cat. Complications are typically minor and infrequent.  相似文献   
183.
Maintaining the health of dogs and cats by feeding wholesome nutritional diets is becoming an important component of responsible pet ownership. Pet owners now seek a long and healthy life for their pet and look to nutrition, as well as to veterinary medicine, to provide such support. Quality of life, measured in terms of reduced incidence of diseases and the ability to maintain an active life, would appear to be able to be enhanced by appropriate nutrition and nutraceutical supplementation. As a consequence numerous improvements in companion animal nutrition have resulted in development of a wide array of foods that provide complete and balanced nutrition. As a result emphasis also has to be placed on product safety and quality parameters, in connection with traceability. The origin of products, including product characteristics and properties, processing conditions and further handling throughout the period chain, is becoming ever increasingly an issue for collective chain management.  相似文献   
184.
Five animals in a colony of cynomolgus monkeys (Macaca fascicularis) died or were euthanatized because of alveolar echinococcosis, during a period of 5 years. The remainder of the colony was screened for possible infection with Echinococcus multilocularis, using serology and ultrasonography. A total of 46 animals out of a group of 55 were examined. The presence of anti-Em2 antibodies analyzed with enzyme-linked immunosorbent assay was demonstrated in 3 monkeys. In 2 of these 3 monkeys, multilocular structures compatible with metacestodal cysts in the liver were identified, using ultrasonography. The presence of alveolar echinococcosis was subsequently confirmed at postmortem examination in 1 animal. The other animals are still alive. Two other monkeys were negative in the serological examination but had cystic structures in the liver, which were identified as bile duct cysts at postmortem examination in 1 animal. The other monkey is still alive. These findings suggest that serology for antibodies against the Em2 antigen may represent a useful method in identifying animals that might be infected with E. multilocularis and are therefore at risk of developing fatal alveolar echinococcosis.  相似文献   
185.
Chondrocytes dedifferentiate to a fibroblast‐like phenotype on plastic surfaces. Dedifferentiation is reversible if these cells are then cultured embedded in gels as alginate, agarose or collagen. Chondrocytes cultured in suspension on a non‐adherent surface are also known to form aggregates of differentiated cells. The knowledge of chondrocyte behavior in culture is relevant for tissue engineering purposes. In this report we describe a simple method to culture differentiated or redifferentiated rabbit auricular chondrocytes on plastic surfaces with a stable phenotype. When chondrocyte aggregates formed in suspension are next seeded on plastic surfaces, most of them attach to the plastic as round or polygonal cells, and this morphological differentiation, confirmed by the presence of type II collagen, is stable for long culture periods. We also report that the addition of aggregates to monolayer cultures of dedifferentiated chondrocytes results in their redifferentiation, as is shown by their morphological changes and the synthesis of type II collagen. Therefore, this simple method can be useful for the study of chondrocyte behavior on plastic surfaces and for redifferentiating previously proliferated chondrocytes in tissue engineering techniques. Furthermore, these results demonstrate that, in addition to culture conditions such as cell isolation method or cell‐density, chondrocyte behavior on plastic depends on the presence or absence of aggregates resulting from the dissociation process.  相似文献   
186.
The endocannabinoid anandamide may regulate intestinal motility through activation of CB1 receptors. Anandamide is then inactivated by fatty acid amide hydrolase (FAAH), a membrane bound enzyme. Under pathological conditions, inactivation of such enzymatic activity may lead to inhibition of the intestinal motility. Here, preliminary reports on the distribution of Fatty Acid Amide Hydrolase (FAAH) immunoreactivity in the mouse gastrointestinal neurons, and the pharmacological effects of N‐arachidonoylserotonin (AA‐5HT), a selective inhibitor of FAAH, are reported. FAAH was revealed by an indirect immunofluorescence. Laminar preparations containing the myenteric or the submucous plexus adhered, were peeled off after the whole gut wall had been stretched out and fixed in 4% paraformaldehyde. They were subsequently incubated with a polyclonal anti‐serum directed against a region near the N‐terminus of the human FAAH and revealed by a FITC‐conjugated goat anti‐rabbit secondary anti‐serum. FAAH‐immunoreactive neurons were observed within the myenteric ganglia throughout the GIT. The positive nerve cells varied in size and density of immunoreactivity. Stomach and large intestine showed the highest neuronal density. AA‐5HT significantly reduced both gastric emptying and gastrointestinal tract transit. Such inhibitory effect was reduced by the C1 receptor antagonist SR141716A. Both morphological and pharmacological results suggest that FAAH may play a critical role in controlling gut anandamide levels.  相似文献   
187.
An individual-based, spatially explicit population model was used to predict the consequences of future land-use alternatives for populations of four amphibian species in two central Iowa (midwest USA) agricultural watersheds. The model included both breeding and upland habitat and incorporated effects of climatic variation and demographic stochasticity. Data requirements of the model include life history characteristics, dispersal behavior, habitat affinities, as well as land use and landcover in geographic information systems databases. Future scenarios were ranked according to change in breeder abundance, saturation, and distribution, compared to baseline conditions. Sensitivity of simulation results to changes in model parameters was also examined. Simulated results suggest that while all four species modeled are likely to persist under present and future scenario conditions, two may be more at risk from future landscape change. Although the study species are all widespread generalists regarded as having a low conservation priority, they depend on wetlands and ponds, increasingly endangered habitats in agricultural landscapes. Broader conservation strategies in the region would ensure that these currently common organisms do not become the endangered species of the future.This revised version was published online in May 2005 with corrections to the Cover Date.  相似文献   
188.
189.
We describe the classification of landscapes characterised bymineral soil using a model that calculates soil moisture availability on amonthly basis. Scotland is used as a case study area. The model uses potentialsoil moisture deficit, estimated using broad scale (40 × 40 km)climate patterns, in conjunction with meteorological station measurements toobtain finer scale values of climatic soil moisture deficit. Point estimates ofsoil available water are obtained for soil characteristics using appropriatepedotransfer functions, and geostatistical techniques are used to upscale theresults and interpolate to a 1-km grid. Known heterogeneityin soil physical characteristics is used to provide local corrections to thepotential soil moisture deficit, estimated using the climatic variables above.Temporal profiles of monthly water content are modelled for each1-km location and classified into six classes usingunsupervised cluster analysis. The spatial distribution of these classesreflects regional variations in the availability of moisture and energy, onwhich finer-grained topographic patterns are superimposed. In the case study,the broad scale spatial heterogeneity of heathlands and grasslands on mineralsoils in Scotland is shown to be strongly related to the soil moistureclassification. The results can be used in studies investigating the patternsofdistribution of communities at the landscape and regional scale.This revised version was published online in May 2005 with corrections to the Cover Date.  相似文献   
190.
Investigations of European floodplain rivers demonstrate how landscape ecology can provide an effective framework to integrate pattern and process in river corridors, to examine environmental dynamics and interactive pathways between landscape elements, and to develop viable strategies for river conservation. The highly complex and dynamic nature of intact river corridors is particularly amenable to a landscape ecology perspective. Analysis of spatial patterns has provided considerable insight into environmental heterogeneity across river corridors and is an essential prelude to examining dynamic interactions. For example, data from aerial photographs, digitized maps and year-round field measurements in a glacial flood plain, enabled us to distinguish six channel types, based on the correspondence between connectivity and physicochemical attributes. Spatial data were also used to analyze longitudinal changes in landscape elements along the course of a morphologically-intact riverine corridor, providing insight into the structural complexity that must have characterized many Alpine rivers in the pristine state. Landscape indices were employed to investigate seasonal dynamics in a glacial flood plain of the Swiss Alps which exhibits a predictable expansion/contraction cycle, with corresponding shifts in flow paths (surface and subsurface) and water sources (snowmelt, englacial, subglacial, alluvial aquifer, hillslope aquifer). Surface connectivity exhibited an unexpected biphasic relationship with total channel length, whereas riverscape diversity progressively increased along the entire range of channel length. Reconstituting the functional integrity that characterizes intact river corridors should perhaps be the major goal of river conservation initiatives. Although understanding functional processes at the landscape scale is essential in this regard, few data are available. In the Alluvial Zone National Park on the Austrian Danube, three phases of hydrological connectivity were identified (disconnection, seepage connection and surface connection) that corresponded to the predominance of three functional processes (biotic interactions, primary production and particulate transport) within the river corridor.  相似文献   
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