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71.
C M Richards H A Aucken E M Tucker D Hannant J A Mumford J R Powell 《Veterinary immunology and immunopathology》1992,33(1-2):129-143
Studies were carried out to determine the optimum conditions for the production of equine monoclonal antibodies (MAbs). Lymphocytes from ponies immunised with influenza A equine 2 virus, isolate A/Equine/Newmarket/79 (H3N8) were fused with mouse myeloma (NSO) cells and with horse-mouse heterohybridomas made aminopterin-sensitive by selective growth in 8-azaguanine. Although all fusions initially resulted in heterohybridoma colonies that secreted equine immunoglobulin, many of these were unable to maintain secretion for longer than a few weeks. Increasing the time between immunisation and the booster injection of Newmarket/79 virus, the inclusion of Freund's incomplete adjuvant and the use of an aminopterin-sensitive primary heterohybridoma as the fusion partner, improved the production of HIg-secreting heterohybridomas. After two clonings eight cell lines were established which maintained anti-Newmarket/79 antibody secretion for over a year. FACS analysis of the cell lines provided a useful means of predicting breakdown of MAb secretion by the cell lines, thus enabling re-cloning to be carried out in time. 相似文献
72.
S A Morrison J Randolph C D Lothrop 《Journal of the American Veterinary Medical Association》1989,194(1):91-94
In this report, we described the clinical, radiographic, and echocardiographic findings in a cat with hypersomatotropism and insulin-resistant diabetes mellitus. Growth hormone determinations were made because of persistent hyperglycemia despite insulin requirements exceeding 2.2 U/kg of body weight, and the acromegalic features of the cat. Also, the results of a therapeutic trial in which a long-acting analogue of somatostatin was used are discussed. 相似文献
73.
F. W. K. Smith Jr DVM L. C. Buoen BA A. F. Weber DVM PhD S. D. Johnston DVM PhD J. F. Randolph DVM D. J. Waters DVM 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1989,3(2):90-95
A 6-month-old stunted female Doberman Pinscher was found to have a 77,X0 chromosomal complement. The ovaries were small, consisting primarily of interstitial-type cells and solid epithelial cords. The dam, sire, and a male littermate had normal karyotypes. 相似文献
74.
Twenty-two nonlactating Hereford cows exhibiting normal estrous cycles were fed either maintenance (M) or restricted (R) diets until most of the R cows became anestrus; R cows then were fed 160% of the M diet until estrous cycles resumed. Concentrations of progesterone, glucose, insulin and nonesterified fatty acids (NEFA) were determined in weekly blood samples. Blood also was collected frequently, before and after i.v. infusion of 300 ml of a 40% glucose solution, to evaluate responses in blood concentrations of glucose and insulin when cows were exhibiting normal estrous cycles, when R cows were initiating anestrus, during anestrus, and at the reinitiation of estrous cycles. Losses in BW and body condition score in R cows were associated with reduced (P less than .01) concentrations of glucose and insulin and greater (P less than .01) concentrations of NEFA in blood plasma compared with those of M cows. During normal estrous cycles, disappearance of infused glucose from plasma and concentrations of insulin in serum were similar for R and M cows. Glucose disappearance from plasma was retarded and serum concentrations of insulin remained increased for a longer time after glucose infusion in R at the start of anestrus compared with M cows (P less than .01). Similarly, during anestrus, the rate of glucose disappearance was slower for R cows (P less than .01). During refeeding of R cows, disappearance of infused glucose was similar for R and M cows. In conclusion, reduced concentrations of glucose and insulin and increased concentrations of NEFA in blood were associated with nutritional anestrus and the glucoregulatory effects of insulin were compromised during nutritional anestrus. 相似文献
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Evaluation of prognostic factors, survival rates, and treatment protocols for immune-mediated hemolytic anemia in dogs: 151 cases (1993-2002) 总被引:4,自引:0,他引:4
Weinkle TK Center SA Randolph JF Warner KL Barr SC Erb HN 《Journal of the American Veterinary Medical Association》2005,226(11):1869-1880
OBJECTIVE: To evaluate prognostic factors, survival, and treatment protocols for immune-mediated hemolytic anemia (IMHA) in dogs. DESIGN: Retrospective study. ANIMALS: 151 dogs with IMHA not associated with underlying infectious or neoplastic disease. PROCEDURE: lnformation recorded from review of medical records included signalment at the time of initial evaluation; vaccination history; 30-, 60-, and 365-day follow-up outcomes; laboratory data; results of imaging studies; and necropsy findings. Dogs were grouped according to the presence of spherocytes, autoagglutination, a regenerative erythrocyte response, and treatments received (azathioprine, azathioprine plus ultralow-dose aspirin, azathioprine plus mixed-molecular-weight heparin [mHEP], or azathioprine plus ultralow-dose aspirin plus mHEP) for comparisons. All dogs received glucocorticoids. RESULTS: Cocker Spaniels, Miniature Schnauzers, neutered dogs, and female dogs were overrepresented. Alterations in certain clinicopathologic variables were associated with increased mortality rate. Rates of survival following treatment with azathioprine, azathioprine plus ultralow-dose aspirin, azathioprine plus mHEP, and azathioprine plus ultralow-dose aspirin plus mHEP were 74%, 88%, 23%, and 70%, respectively, at hospital discharge; 57%, 82%, 17%, and 67%, respectively, at 30 days; and 45%, 69%, 17%, and 64%, respectively, at 1 year. In comparison, mean survival rates at discharge and at 30 days and 1 year after evaluation collated from 7 published reviews of canine IMHA were 57%, 58%, and 34%, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Treatment with a combination of glucocorticoids, azathioprine, and ultralow-dose aspirin significantly improved short- and long-term survival in dogs with IMHA. 相似文献
80.
The air temperatures inside uninsulated and insulated huts were recorded on an outdoor pig unit in the south of England between September 1997 and September 1998, and the herd's production parameters were also recorded. During the summer the temperatures inside some of the uninsulated huts exceeded 45 degrees C, but the temperatures inside the insulated huts were lower and fluctuated less. Despite the high temperatures, the weaning weight of piglets reared in the uninsulated huts were often higher than those of the piglets reared in the insulated huts, possibly as a result of the higher mortality of small piglets in the uninsulated huts, especially during the winter. The weaning weights of the piglets were higher during the summer. 相似文献