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OBJECTIVE: To evaluate the cardiovascular effects of the alpha2-adrenergic receptor agonist medetomidine hydrochloride in clinically normal cats. ANIMALS: 7 clinically normal cats. PROCEDURE: Cats were anesthetized with isoflurane, and thermodilution catheters were placed for measurement of central venous, pulmonary, and pulmonary capillary wedge pressures and for determination of cardiac output. The dorsal pedal artery was catheterized for measurement of arterial blood pressures and blood gas tensions. Baseline variables were recorded, and medetomidine (20 microg/kg of body weight, IM) was administered. Hemodynamic measurements were repeated 15 and 30 minutes after medetomidine administration. RESULTS: Heart rate, cardiac index, stroke index, rate-pressure product, and right and left ventricular stroke work index significantly decreased from baseline after medetomidine administration, whereas systemic vascular resistance and central venous pressure increased. However, systolic, mean, and diastolic arterial pressures as well as arterial pH, and oxygen and carbon dioxide tensions were not significantly different from baseline values. CONCLUSIONS AND CLINICAL RELEVANCE: When administered alone to clinically normal cats, medetomidine (20 microg/kg, IM) induced a significant decrease in cardiac output, stroke volume, and heart rate. Arterial blood pressures did not increase, which may reflect a predominant central alpha2-adrenergic effect over peripheral vascular effects.  相似文献   
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Reports of bovine viral diarrhea virus (BVDV) infections in alpacas have been increasing in recent years but much is still unknown about the mechanisms of disease in this species. This report characterizes the transmission of BVDV from persistently infected (PI) alpacas to BVDV naïve alpacas, documents shedding patterns, and characterizes the disease effects in both PI and transiently infected alpacas. Two PI alpacas shed BVDV Type 1b virus in most body fluids, and commonly available diagnostic tests verified their status. Bovine viral diarrhea virus Type 1b transient infections produced only mild signs of disease in BVDV naïve alpacas. Viremia was detected in whole blood, but viral shedding during the acute phase was not detected and antibody appeared to be protective upon re-exposure to the virus.  相似文献   
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In spring 2009 several cases of infestation with Ornithonyssus bacoti (?tropical rat mite?) in pet rodents have been diagnosed at the Institute of Parasitology, University of Zurich. Although adequate animal hosts were present, owners also became victims of mite infestation. The owners presented cutaneous lesions such as pruritic red papules partly with a central vesicle, predominantly disposed in groups. Particularly children with close body contact to their pet rodents were strongly affected. Because the definite diagnosis was usually yielded at a late time-point, the medical treatment remained unsatisfactory in some cases. The mite-infestation of the pets was mostly detected after the owners also became affected. The owners noticed merely non-specific signs such as increased restlessness, itching and shaggy coat on their animals. Efficient healing was achieved only if the parasites were completely eliminated, i.e. also the pets were treated, the cages cleaned and the apartments professionally disinfested. A definite diagnosis of ?Infestation with Ornithonyssus bacoti? is only possible by means of morphological identification on an isolated mite, which is most likely to be found in the environment of the animals. Pet owners should be informed about the zoonotic potential of O. bacoti.  相似文献   
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Rain-cracking of post-veraison grape berries (Vitis vinifera L.) reduces yield and quality of must and wine. Under vineyard conditions, cracking is often associated with bunch rots. The objective of the present study was to identify the role of Botrytis cinerea Pers.: Fr. as the dominant bunch rot fungus in cracking of Riesling berries. For these experiments grape berries with characteristic symptoms of Botrytis infections were selected in the vineyard. Berries infected by Botrytis always cracked in those regions of the berry where symptoms of the infections (brownish purple colour of the fruit skin) were present. In 55 % of these berries, cracks were orientated perpendicularly to the pedicel/stylar scar axis. Microscopic cracks referred to as microcracks were often present in the stylar scar region and occasionally in the vicinity of lenticels. These cracks allowed penetration of the fluorescent tracer acridine orange. The area infiltrated by the dye was positively related to crack length (r2?=#x003D;?0.43*). Water uptake of detached berries increased with time. Rates of uptake were highly variable and higher for infected berries as compared to berries without infections. Rates of water uptake into infected berries were positively related to cumulative crack length (number of cracks multiplied with average crack length) per berry (r2?=#x003D;?0.45*). Exposing the outer surface of the strained grape berry exocarp to water increased the frequency of microcracks. The increase was larger in infected berries than in those without symptoms. Our data demonstrate that Botrytis infections increase the cracking susceptibility of Riesling grape berries by weakening the grape berry exocarp, increasing crack length per berry which in turn resulted in increased water uptake.  相似文献   
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