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OBJECTIVE: To examine changes between 1996 and 2004 in regard to numbers of animals handled, medical care provided, expenses, numbers of employees, and agency policies for animal care and control agencies in Ohio. DESIGN: Cross-sectional survey. SAMPLE POPULATION: 223 animal care and control agencies. PROCEDURES: A questionnaire was mailed to animal care and control agencies in Ohio to collect information for 2004; results were compared with published results of a similar survey. RESULTS: 165 of the 223 (74%) agencies responded. Estimated total number of animals handled in 2004 was 315,519, which represented a decrease of 7% compared with 1996. However, although number of dogs taken in decreased 17%, number of cats taken in increased 20%. Between 1996 and 2004, the euthanasia rate decreased from 65.3% to 56.8%, and the adoption rate increased from 24.5% to 33.6%. Number of dogs euthanatized decreased 39%, but number of cats euthanatized increased 14%. The proportion of agencies with a spay-neuter policy increased from 56% to 71%, and the proportion that maintained an association with a veterinarian increased from 39% to 80%. For dogs handled by county dog warden agencies, the odds of euthanasia were higher if the agency did not have a spay-neuter policy (odds ratio, 1.36). CONCLUSIONS: Results suggest that the status of dogs handled by animal care and control agencies in Ohio improved between 1996 and 2004, but that the status of cats deteriorated.  相似文献   
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To establish a well-tolerated technique for recording electrocardiograms (ECGs) and a reference range for the normal pet rabbit ECG, 46 healthy pet rabbits were studied. The following reference ranges were calculated. Heart rate was 198 to 330 bpm. P waves had a duration of 0.01 to 0.05 seconds and an amplitude of 0.04 to 0.12 mV. The P-R interval was 0.04 to 0.08 seconds and the duration of the QRS complex was 0.02 to 0.06 seconds. The amplitude of the R wave was 0.03 to 0.39 mV. The Q-T interval was 0.08 to 0.16 seconds. The amplitude of the T wave was 0.05 to 0.17 mV. Mean electrical axis was found to be -43° to +80°. Evidence of variation due to breed or bodyweight was not found to be significant, except for a quadratic relationship between R wave amplitude and bodyweight. The ECG recording technique used in this study for pet rabbits was well tolerated and shown to be both reliable and repeatable.  相似文献   
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Abstract. A national agri-environmental database and nitrate modelling system has been developed to support the UK government's nitrate policy development. The framework, 'MAGPIE', consists of a database and models linked within a Geographical Information System and provides a user interface which allows detailed spatial and statistical investigation of the current state (data and model output) and the impact of changes in conditions or agricultural practice. Data on crops and livestock numbers taken from the annual agricultural census were modified in relation to land cover data derived from remote sensing, and other sources. These data and data on climate, soils and altitude were interpolated to a 1 km grid. The models of nitrate loss were adapted to work with this data set while retaining as far as possible the salient features of the more detailed models and data from which they were derived. The resulting Policy Decision Support System was found to give estimates of mean annual flow and nitrate load for agricultural catchments which matched measured data closely. The system has contributed to work on a number of policy issues both within the UK and in the UK's contribution to international policy development on pollution derived from agriculture.  相似文献   
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The radiographic changes caused by collapse of lung lobes in pulmonary disease, pneumothorax, and pleural effusion depend on the lobar recoiling force and local pleural pressure. Differences in the tendency of normal lung lobes or regions to collapse depend on the relative surface-to-volume ratio, determined by shape and size of the region or lobe. This ratio affects the physiologic parameters of pulmonary interdependence, compliance, and collateral air flow. Pulmonary surfactant increases compliance, particularly at low volumes, maintains alveolar stability, and assists in maintaining capillary patency and preventing pulmonary edema. Its loss due to lung injury increases collapsing forces. In the presence of pneumothorax or pleural effusion, diseases that cause lobar collapse produce localized air or fluid entrapment that is a diagnostic sign of the presence of the underlying pulmonary disease.  相似文献   
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Blood clots perform an essential mechanical task, yet the mechanical behavior of fibrin fibers, which form the structural framework of a clot, is largely unknown. By using combined atomic force-fluorescence microscopy, we determined the elastic limit and extensibility of individual fibers. Fibrin fibers can be strained 180% (2.8-fold extension) without sustaining permanent lengthening, and they can be strained up to 525% (average 330%) before rupturing. This is the largest extensibility observed for protein fibers. The data imply that fibrin monomers must be able to undergo sizeable, reversible structural changes and that deformations in clots can be accommodated by individual fiber stretching.  相似文献   
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OBJECTIVE: To investigate effects of IV administered carprofen on indices of renal function and results of serum biochemical and hematologic analyses in dogs anesthetized with acepromazine-thiopentone-isoflurane that had low blood pressure during anesthesia. ANIMALS: 6 healthy Beagles. PROCEDURE: A randomized crossover study was conducted, using the following treatments: saline (0.9% NaCl solution)-saline, saline-carprofen, and carprofen-saline. Saline (0.08 ml/kg) and carprofen (4 mg/kg) were administered IV. The first treatment was administered 30 minutes before induction of anesthesia and immediately before administration of acepromazine (0.1 mg/kg, IM). Anesthesia was induced with thiopentone (25 mg/ml, IV) and maintained with inspired isoflurane (2% in oxygen). The second treatment was administered 30 minutes after onset of inhalation anesthesia. Blood gases, circulation, and ventilation were monitored. Renal function was assessed by glomerular filtration rate (GFR), using scintigraphy, serum biochemical analyses, and urinalysis. Hematologic analysis was performed. Statistical analysis was conducted, using ANOVA or Friedman ANOVA. RESULTS: Values did not differ significantly among the 3 treatments. For all treatments, sedation and anesthesia caused changes in results of serum biochemical and hematologic analyses, a decrease in mean arterial blood pressure to 65 mm Hg, an increase of 115 pmol/L in angiotensin II concentration, and an increase of 100 seconds in time required to reach maximum activity counts during scintigraphy. CONCLUSIONS AND CLINICAL RELEVANCE: Carprofen administered IV before or during anesthesia did not cause detectable significant adverse effects on renal function or results of serum biochemical and hematologic analyses in healthy Beagles with low blood pressure during anesthesia.  相似文献   
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