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71.
OBJECTIVE: To identify dietary factors in commercially available canned foods associated with the development of calcium oxalate (CaOx) uroliths in dogs. ANIMALS: 117 dogs with CaOx uroliths and 174 dogs without urinary tract disease. PROCEDURE: Case dogs were those that developed CaOx uroliths submitted to the Minnesota Urolith Center for quantitative analysis between 1990 and 1992 while fed a commercially available canned diet. Control dogs were those without urinary tract disease evaluated at the same veterinary hospital just prior to or immediately after each case dog. A content-validated multiple-choice questionnaire was mailed to each owner of case and control dogs with the permission of the primary care veterinarian. Univariate and multivariate logistic regressions for each dietary component were performed to test the hypothesis that a given factor was associated with CaOx urolith formation. RESULTS: Canned foods with the highest amount of protein, fat, calcium, phosphorus, magnesium, sodium, potassium, chloride, or moisture were associated with a decreased risk of CaOx urolith formation, compared with diets with the lowest amounts. In contrast, canned diets with the highest amount of carbohydrate were associated with an increased risk of CaOx urolith formation. CONCLUSIONS AND CLINICAL RELEVANCE: Feeding canned diets formulated to contain high amounts of protein, fat, calcium, phosphorus, magnesium, sodium, potassium, chloride, and moisture and a low amount of carbohydrate may minimize the risk of CaOx urolith formation in dogs.  相似文献   
72.
A method for the separation of pure and viable lymphocytes and granulocytes from the same blood sample in horses was reported. By centrifuging equine heparinized blood at 100 xg for 10 min at room temperature (r.t.), the resulting supernatant plasma was an almost pure (97.71 +/- 0.30%; n = 15) suspension of highly viable (98.72 +/- 0.28%) lymphocytes. When sodium citrate was used as an anticoagulant, lymphocyte suspensions collected in the same manner showed lower purity (87.89 +/- 1.59%; n = 9) and higher yields (56.56 +/- 3.89%, n = 9 versus 36.11 +/- 2.23%, n = 15). Where needed, a further centrifugation at 250 xg for 3 min (r.t.) of heparinized lymphocyte preparations removed an average of 87.39% (n = 15) contaminating platelets. A suspension of 85.96 +/- 2.20% pure granulocytes (93.23 +/- 1.74% neutrophils; n = 14) with minimal contamination by erythrocytes and high viability (93.11 +/- 1.26%) was obtained by performing a flash red blood cell lysis on the white-greyish layer resulting from the centrifugation of the heparinized blood samples. Among the several methods available, the procedure described herein is easy, rapid, cheap and reproducible.  相似文献   
73.
The pathogenesis of chicken infectious anaemia virus (CAV) infection was studied in 6-week-old and one-day-old SPF chickens inoculated intramuscularly with graded doses of Cux-1 strain (10(6)-10(2) TCID50/chicken). Viraemia, virus shedding, development of virus neutralizing (VN) antibodies and CAV distribution in the thymus were studied by virus isolation, polymerase chain reaction (PCR), immunocytochemistry (IP) and in situ hybridization until postinfection day (PID) 28. In 6-week-old chickens infected with high doses of CAV, viraemia and VN antibodies could be detected 4 PID and onward without virus shedding or contact transmission to sentinel birds. However, virus shedding and contact transmission were demonstrated in one-day-old infected chickens. In the 6-week-old groups infected with lower doses, VN antibodies developed by PID 14, transient viraemia and virus shedding were detected. The thymus cortex of all 1-day-old inoculated chickens stained with VP3-specific mAb. Cells with positive in situ hybridization signal were fewer and scattered throughout the thymus tissue of the one-day-old inoculated chickens as compared to IP-positive cells. These results suggest that early immune response induced by high doses of CAV in 6-week-old chickens curtails viral replication and prevents virus shedding.  相似文献   
74.
The radiographic appearance of the cribriform plate was investigated in 16 canine cadaver heads. The cribriform plate appeared as a "V"-shaped multilinear bone-opaque stripe in the caudal nasal region in projections perpendicular to the hard palate in 6 dogs with a skull index between 50.00 and 54.00. In 9 dogs with a skull index between 55.40 and 74.40, the cribriform plate had a more "C"-shaped and sharp appearance. In vertically oblique projections with an obliquity greater than 20 degrees, the cribriform plate lost its sharp outline and finally (40 degrees) disappeared. In lateral projections the cribriform plate appeared as a "C"-shaped interrupted bone-opaque stripe in all 16 dogs. In more brachycephalic dogs frontal bone structures superimposed on the cribriform plate on ventrodorsal and dorsoventral views and accentuated the radiographic appearance of the plate. Vertically oblique views separated both structures to produce two lines.  相似文献   
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77.
Objective: To describe a case of confirmed baclofen intoxication in a dog that was successfully treated with hemodialysis and hemoperfusion (HD/HP) and to report the serum baclofen kinetics. Case summary: A 2.5‐year‐old, 23 kg, spayed female Brittany Spaniel‐mix was treated after ingesting 21‐52 mg/kg of baclofen. The dog was comatose and was receiving manual ventilation at the time of presentation. Extracorporeal HD/HP was started 10 hours after admission. Within 3 hours of starting HD/HP the dog began initiating breaths and was extubated 18 hours after admission. Serial serum samples that were obtained during the first 24 hours of hospitalization were later analyzed for baclofen concentrations. The dog had elevated creatine phosphokinase and liver enzymes that correlated with an agitated recovery period. The dog had thrombocytopenia that resolved by 10 days after presentation. New or unique information provided: HD/HP shortened the baclofen serum elimination half‐life from 5 to 1.5 hours in the initial 2 hours of treatment. The intrinsic elimination rate constant (Kintr) for this dog was 0.138/hour and the total elimination rate constant (Ktot) during the first 2 hours of HD/HP treatment was 0.458/hour. In this dog, HD/HP was an effective method for rapidly decreasing serum baclofen concentration after an acute overdose.  相似文献   
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79.
ObjectivesThis study measured plasma atrial natriuretic peptide (ANP) concentration in horses with heart valve regurgitations (HVR) with and without atrial and ventricular dilatation.BackgroundIn humans and small animals, plasma ANP concentration is increased in heart disease and correlates with the severity of clinical signs and heart enlargement.Animals, materials and methodsTen healthy horses (control) and 36 horses with HVR were evaluated by auscultation, electrocardiography, echocardiography, and determination of plasma ANP.ResultsControl horses demonstrated mean plasma ANP concentration of 21 ± 5.4 pg/mL. Of the 36 horses with HVR, 17 horses possessed normal echocardiographic heart size (group 1), 10 horses had a left atrial dilatation (group 2) and 9 horses had both left atrial and ventricular dilatation (group 3). Mean plasma ANP concentration of groups 1, 2 and 3 was 20.1 ± 5.6 pg/mL, 22.9 ± 11.0 pg/mL and 27.6 ± 17.4 pg/mL, respectively. The plasma ANP concentrations of HVR and control horses were not significantly different. The highest ANP concentrations were observed in horses with atrial and ventricular dilatation. No correlation between left atrial or ventricular size, weight, or sex and the plasma ANP concentration was found.ConclusionsNo significant differences in plasma ANP concentration was observed between groups. Further study, especially in horses with clinical signs of heart failure is needed.  相似文献   
80.
一、诱导母猪发情与发情检测 发情是后备母猪受胎能力和筛选的标记,是经产母猪受胎能力的标记,以及输精时间的标记。[第一段]  相似文献   
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