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41.
To investigate effects of thermally-induced testicular degeneration on hormonal and seminal parameters in stallions, the scrotum was insulated for 36 hours in two mature (5-year-old mixed breed and 11-year-old Throughbred) stallions. Semen was collected daily for 10 days (DSO) prior to, and at intervals after, scrotal insulation. When DSO determinations were not being made, semen was collected 3 times weekly. Jugular blood samples were collected at 15-minute intervals for 6 hours from each stallion prior to, and at intervals after, scrotal insulation. A mouse interstitial cell testosterone assay was modified to quantify biologic activity of equine luteinizing hormone (BLH) in plasma samples. Immunoactive luteinizing hormone (ILH) and testosterone (T) concentrations were determined in plasma samples by routine RIA procedures. Percentages of progressively motile and morphologically normal spermatozoa began to decrease by 1 to 2 weeks postinsulation, reached nadir values at 3 to 3-1/2 weeks postinsulation, and returned to preinsulation values by 7 weeks postinsulation. Total number of spermatozoa and total number of progressively motile, morphologically normal spermatozoa in ejaculates at DSO returned to normal by 8 weeks postinsulation in stallion 2 and 12 weeks postinsulation in stallion 1. Concentrations of BLH and ILH increased, and while T concentrations decreased, immediately postinsulation. The increase in ILH concentrations was greater than the increase in BLH concentrations, resulting in a decrease in the BLH:ILH (B:I) ratio. Following the peak in LH secretion immediately postinsulation, LH concentrations gradually decreased while T concentrations increased. The B:I ratio was elevated from 1 to 13 weeks postinsulation compared to immediately postinsulation. In addition to changes in spermatozoal quality in ejaculates, stallion response to scrotal insulation included increased secretion of luteinizing hormone and impaired Leydig cell function (as determined by reduced testosterone concentration in circulating plasma). The proportion of biologically active LH secreted in response to thermal testicular injury increased during the recovery phase.  相似文献   
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43.
A duplex ultrasound system incorporating a pulsed wave Doppler ultrasound probe with conventional B-mode real-time imaging was used to evaluate portal vein blood flow in eight normal dogs. Adequate visualization of the cranial abdominal vessels was obtained from the right lateral 11th or 12th intercostal space. Doppler spectral analysis showed non-pulsatile flow with a wide range of linear flow velocities across the vessel lumen typical of laminar blood flow. Results for portal vein blood flows were 49.8 ± 13.5 ml/min/kg body weight (mean ± SD) with a range of 37.8 - 76.8 ml/min/kg body weight. These values overestimate portal blood flow by approximately 2 times when compared with published studies using invasive techniques. This overestimation is primarily due to the use of the maximal flow velocity in the blood flow calculations.  相似文献   
44.
We evaluated three reflectance meters (Accu-Chek II, Glucometer II, and Glucoscan 2000) and two reagent strips (Chemstrip bG and Glucostix) for accuracy and precision in determining blood glucose concentrations in the dog. To evaluate accuracy, we compared results of blood glucose determinations performed on 95 samples using the various strips and meters vs. the glucose concentrations obtained using the glucose-oxidase method on a Beckman Glucose Analyzer. Accuracy was evaluated statistically using least squares regression analysis. To evaluate precision, samples in various ranges of blood glucose concentration were tested repeatedly (20 times within a 1-hour period) on the same reflectance meter. Coefficient of variation (CV) was determined to evaluate reproducibility of results. Overall, there were significant correlations (P less than 0.001) between the laboratory glucose values and the blood glucose concentrations obtained with Chemstrip bG (r = 0.976), Glucostix (r = 0.904), Accu-Chek II (r = 0.986), Glucometer II (r = 0.911) and Glucoscan 2000 (r = 0.944). In the precision study, all three meters had excellent CVs in the normal range (3.6% to 4.9%). However, Accu-Chek II was found to be more precise in the hypoglycemic and hyperglycemic ranges (3.6% and 2.6%, respectively) than either Glucometer II (8.8% and 5.4%) or Glucoscan 2000 (7.8% and 8.2%). The results of this study indicate that all of the meters and reagent strips tested are highly accurate in determining blood glucose concentrations in the dog. However, both in terms of accuracy and reproducibility of results, Accu-Chek II and Chemstrip bG, gave the highest correlation coefficients and, as such, are probably of the greatest clinical value.  相似文献   
45.
Pulmonary function testing is a relatively new area in clinical veterinary medicine, with few individuals currently obtaining TBFVL and pulmonary mechanics on a clinical cases of respiratory disease in dogs and cats. ABG analysis is a technique available to all veterinarians through commercial laboratories or local hospitals. Information obtained from these tests will allow for a better understanding of the pathophysiology of naturally occurring diseases as well as assisting in the determination of the efficacy of various therapeutic agents (such as bronchodilators), which to date has been lacking in veterinary medicine.  相似文献   
46.
Treatment of small animal respiratory diseases tends to target bronchodilators. Although this is not inappropriate, recent advances in the understanding of respiratory diseases have underscored the importance of inflammatory mediators in the pathophysiology of respiratory diseases. Drug therapy of the respiratory tract in small animals is most successful when it is based on a knowledge of normal physiology and disease pathophysiology of respiratory tract diseases.  相似文献   
47.
Cisplatin Therapy in 41 Dogs With Malignant Tumors   总被引:3,自引:0,他引:3  
Forty-one dogs with a variety of histopathologically diagnosed, measurable tumors were treated with cisplatin (cis-diamminedichloroplatinum, Platinol, Bristol Laboratories, Syracuse, NY 13221-4755) as a single agent at a dosage of 60 mg/m2 given intravenously at 3-week intervals. In an attempt to avoid renal toxicity of cisplatin, saline diuresis was induced and maintained for 4 hours before and 2 hours following cisplatin administration. The dogs received one to ten doses of cisplatin. To determine response to therapy and to monitor toxicity of the drug, the dogs were evaluated with physical examinations including tumor measurements, radiography, complete blood counts, platelet counts, urinalyses, serum urea nitrogen concentrations, and serum creatinine concentrations. An overall response rate of 19% was observed. Complete remission occurred in one of 11 dogs with squamous cell carcinomas and one of one dog with a mediastinal undifferentiated carcinoma. Partial remissions were documented in one of 11 dogs with squamous cell carcinomas, two of three dogs with metastatic osteosarcomas, one of three dogs with nasal adenocarcinomas, and one of one dog with a thyroid adenocarcinoma. Toxic side effects were primarily gastrointestinal in nature, with vomiting occurring 1-6 hours after cisplatin administration in 27 of 41 dogs. Severe anorexia occurred in three dogs, and hemorrhagic diarrhea was observed in one dog. One dog developed grand mal seizures and died 3 hours following therapy. Granulocytopenia was documented in six dogs, and thrombocytopenia was observed in four dogs. One dog showed an increase in serum urea nitrogen and creatinine concentrations, but this patient had known pre-existing renal disease.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
48.
The endobronchial anatomy of 10 inflated, air-dried, canine lungs and 8 healthy anesthetized, sternally recumbent, mixed-breed dogs was evaluated, using a flexible fiberoptic bronchoscope. On the basis of the order of branching of lobar and segmental bronchi observed in these lungs, a nomenclature system was devised to systematically identify individual lobar, segmental, and subsegmental bronchi during bronchoscopy in the dog.  相似文献   
49.
The objectives of this study were to compare the growth rates of normal thoroughbred foals to previously reported growth rates1 and to compare growth rates of normal foals with foals diagnosed with cervical vertebral malformation (CVM). Fifty-six foals from two foals crops were used, and eight of these foals were diagnosed with CVM. Growth rate analysis of the CVM foals had to be restricted to the period prior to diagnosis because once these foals were diagnosed, they were treated differently from the normal foals. Body measurements taken at 7 day intervals were body weight, wither height, hip height, and heart girth. For statistical analysis, data were broken down into 30 day intervals. Results showed that the growth rates for normal thoroughbred foals have not changed in the past fifteen years. The CVM foals tended to be heavier and taller during some time intervals than the normal foals, but there were no significant differences between the two groups in any of the skeletal growth measurements. Body weight gain was faster in CVM foals from 31–60 d (p<.01), 121–150 d (p<.01), and 211–240 d (P –.05).  相似文献   
50.
Soft tissue- and bone-phase scintigrams were acquired from 4 normal horses before and over a 14-day period after metacarpophalangeal, antebrachiocarpal, tarsocrural and tarsometatarsal joint blocks. Images were evaluated subjectively and quantitatively for increased activity in these regions. The antebrachiocarpal block resulted in obvious focal accumulation of activity on soft tissue-phase scintigrams. This increased activity was greatest 2 to 4 days postanesthesia and persisted up to 14 days postanesthesia. On quantitative analysis of soft tissue-phase images, similar trends were noted after the metacarpophalangeal and tarsocrural blocks, but these increases were relatively mild and were not evident on subjective evaluation of the images. Abnormal soft tissue-phase activity was not associated with the tarsometatarsal block. On bone-phase scintigrams, increased activity was not present following any of these joint blocks.  相似文献   
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