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排序方式: 共有1045条查询结果,搜索用时 15 毫秒
1.
M O Furr M V Crisman J Robertson O Barta W S Swecker 《Journal of the American Veterinary Medical Association》1992,201(2):307-309
Immune system dysfunction and immunoglobulin deficiency was diagnosed in a 2-year-old horse with disseminated lymphosarcoma. Prolonged (35 days) parenteral nutrition was delivered to support the horse during a period in which immune function studies could be performed. Correction of nutritional compromise by use of parenteral nutrition did not correct the immunoglobulin deficiency, and results of lymphocyte phenotype testing did not indicate abnormal proportions of leukocytes. Lymphoblast transformation studies were suggestive of a circulating immunosuppressive factor in the horse's serum. Normal cell function was detected when the cells were stimulated in precolostral equine serum. 相似文献
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1. White blood cell responses of broilers, turkeys and ducks were examined at regular intervals after being subjected to various degrees of food restriction. 2. Restricted-fed broilers showed increases in heterophil and basophil numbers, together with a corresponding decrease in lymphocytes. The heterophil/lymphocyte ratio was raised. There were no differences between broiler strains. 3. After only one week of feeding restricted diets, heterophils were significantly raised in selected and unselected 2-week-old ducks. At 21 weeks of age, those ducks receiving 50% of food required to achieve their ad libitum-fed body weight had raised heterophils. 4. Ducks receiving food to achieve 25% of ad libitum-fed birds produced a marked basophilia, but no heterophilia. 5. After two weeks of food restriction, turkeys responded with significant heterophil/lymphocyte ratios following two degrees of restricted feeding. 6. It was concluded that in some poultry, a heterophilia may be the response to mild to moderate stress but a basophilia may result after severely stressing birds. 相似文献
3.
Christopher L. Mariani DVM Simon R. Platt BVMS MRCVS Susan M. Newell DVM MS Scott P. Terrell DVM Cheryl L. Chrisman DVM MS EDS Roger M. Clemmons DVM PhD 《Veterinary radiology & ultrasound》2001,42(6):524-531
A 3-year-old neutered female mixed breed dog was examined because of severe, generalized seizure activity, tetraparesis, and encephalopathic signs. Cerebrospinal fluid (CSF) evaluation was unremarkable except for a mild increase in protein. Serum and CSF titers for infectious diseases were negative. Magnetic resonance (MR) imaging examination of the brain was performed and lesions were found within the cerebral gray matter of the temporal and parietal lobes. The lesions had increased signal intensity on T1, T2, and proton density-weighted images. There was mild inhomogeneous enhancement following intravenous contrast medium administration. Neurologic status improved and the seizures were well controlled, but the dog never regained normal mentation and euthanasia was performed 10 weeks after initial evaluation. At necropsy, severe cerebral cortical necrosis was found in the regions corresponding to the lesions seen on MR imaging examination. Large numbers of fat-containing macrophages (gitter cells) were found within these areas, and are thought to be responsible for the characteristic hyperintensity seen on the MR images. 相似文献
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LARRY G. CARPENTER DVM DONALD L. PIERMATTEI DVM PhD Dipiomate ACVS MOWAFAK D. SALMAN BVMS PhD Dipiomate ACVPM E. CHRISTOPHER ORTON DVM PhD Dipiomate ACVS A. WENDELL NELSON DVM PhD Dipiomate ACVS DANIEL D. SMEAK DVM Dipiomate ACVS PAUL B. JENNINGS Jr. VMD MS Dipiomate ACVS ROBERT A. TAYLOR DVM MS Dipiomate ACVS 《Veterinary surgery : VS》1991,20(6):373-378
Cadavers were compared with live anesthetized dogs for their effectiveness as models for surgical training of veterinary medical students. One group of students was trained using cadavers, and a peer group was trained using live anesthetized dogs. Both groups then performed an intestinal anastomosis using a live subject. The time to completion of the procedure was recorded. The anastomoses and celiotomy closures were evaluated. Each anastomosis was isolated and pressure tested. Reviewers blindly scored each surgical team's performance based on actual inspection of the surgical site and on viewing videotapes of the procedure. The participants' attitudes toward the use of live animals in teaching and research were documented before and after training. No statistically significant differences could be detected between the two groups. The results suggest that some substitution of cadavers for live dogs in surgical training might be feasible. 相似文献
6.
This article reviews recent diagnostic procedures that have arisen over the last 10 years. Videoendoscopy of horses on a high-speed treadmill allows observation of some of the changes that take place in a horse's airway during exercise. Measurements of upper airway airflows and transupper airway pressure, the use of an esophageal balloon and a Ventigraph to measure changes in pleural pressure, and pulmonary function testing are new techniques that aid the researcher in understanding the mechanics and pathologic characteristics of airway diseases and help the practitioner in assessing the severity of a problem, measuring response to therapy, and accurately determining a prognosis. 相似文献
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S A Robertson 《Veterinary Clinics of North America: Small Animal Practice》1989,19(2):289-306
The body regulates pH closely to maintain homeostasis. The pH of blood can be represented by the Henderson-Hasselbalch equation: pH = pK + log [HCO3-]/PCO2 Thus, pH is a function of the ratio between bicarbonate ion concentration [HCO3-] and carbon dioxide tension (PCO2). There are four simple acid base disorders: (1) Metabolic acidosis, (2) respiratory acidosis, (3) metabolic alkalosis, and (4) respiratory alkalosis. Metabolic acidosis is the most common disorder encountered in clinical practice. The respiratory contribution to a change in pH can be determined by measuring PCO2 and the metabolic component by measuring the base excess. Unless it is desirable to know the oxygenation status of a patient, venous blood samples will usually be sufficient. Metabolic acidosis can result from an increase of acid in the body or by excess loss of bicarbonate. Measurement of the "anion-gap" [(Na+ + K+) - (Cl- + HCO3-)], may help to diagnose the cause of the metabolic acidosis. Treatment of all acid-base disorders must be aimed at diagnosis and correction of the underlying disease process. Specific treatment may be required when changes in pH are severe (pH less than 7.2 or pH greater than 7.6). Treatment of severe metabolic acidosis requires the use of sodium bicarbonate, but blood pH and gases should be monitored closely to avoid an "overshoot" alkalosis. Changes in pH may be accompanied by alterations in plasma potassium concentrations, and it is recommended that plasma potassium be monitored closely during treatment of acid-base disturbances. 相似文献