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991.
992.
Ectopic teeth occur because of failure of the first branchial cleft to close during development and are found mostly in young horses. Such dentigerous cysts are often located at the base of the ear, forming a notable swelling with a fistula, as it was the case with the two year old Iceland mare ?Runa?. In order to confirm the diagnosis, x-ray images were taken, which is also necessary to locate the ectopic tooth correctly. While operating, the whole cystic membrane should be removed and it is important to prevent adjacent nerves and blood vessels from damage. Prognosis for complete healing after removing an ectopic tooth is excellent.  相似文献   
993.
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995.
Understanding the inherent radiosensitivity and repair capacity of canine transitional cell carcinoma (TCC) can aid in optimizing radiation protocols to treat this disease. The objective of this study was to evaluate the parameters surviving fraction at 2 Gy (SF(2) ), α/β ratio and capacity for sublethal damage repair (SLDR) in response to radiation. Dose-response and split-dose studies were performed using the clonogenic assay. The mean SF(2) for three established TCC cell lines was high at 0.61. All the three cell lines exhibited a low to moderate α/β ratio, with the mean being 3.27. Two cell lines exhibited statistically increased survival at 4 and 24 h in the dose-response assay. Overall, our results indicate that the cell lines are moderately radioresistant, have a high repair capacity and behave similarly to a late-responding normal tissue. These findings indicate that the radiation protocols utilizing higher doses with less fractionation may be more effective for treating TCC.  相似文献   
996.
Long-term studies of megestrol acetate and chlormadinone acetate in 100 female dogs are in progress. Doses of zero, one, 10 and 25 times the expected human dose of megestrol acetate and 25 times the expected human dose of chlormadinone acetate (on a milligram per kilogram body weight basis) are being given daily. During the first 4 years, eight dogs from each of the five groups were killed. The principal gross findings included enlarged uteri with mucoid material in the lumina, mammary development in dogs given middle and high doses of megestrol acetate and chlormadinone acetate, and thickened gallbladder walls in dogs given high doses of each. Histologic evaluation showed inhibition of ovulation for progestogen-treated dogs and suppression of ovarian follicular development with the high doses. Cystic endometrial hyperplasia was slight in the low-dose dogs and moderate to severe in most of the high-dose dogs; a few also had ulcerative endometritis and pyometra. The mammary glands of dogs given the middle and high doses produced lobules, acini, and secretion exceeding natural metestrus. Slight to marked cystic mucinous hyperplasia occurred in the gallbladders of most dogs given the high doses. Tow high-dose megestrol dogs had clinical signs and microscopic pancreatic, renal, and ocular changes indicative of diabetes mellitus.  相似文献   
997.
A method is described for production of an equine anti-bovine leukocyte serum (EABLS). Leukocytes were harvested from the milk of cow's udders which had been irritated with endotoxin. The washed leukocytes as antigens were administered to 2 horses in a series of subcutaneous and intravenous injections. There was a variably progressive increase in total serum proteins and a decrease in albumin/blobulin ratios, but the most pronounced change was an increase in beta2-globulins. Accompanying these changes was an increase in the number of precipitin lines as shown by Ouchterlony analysis. Four old cows and 2 calves were intravenously given a 50- and 20-ml dose, respectively, of the EABLS. Two of the cows and 1 of the calves were given the EABLS which had been heated to 56 C for 30 minutes. Both calves and the 2 cows given heated EABLS and 1 cow given unheated EABLS developed marked neutropenia within the 1st hour. The 4th cow given unheated EABLS developed only slight neutropenia. It was concluded that there may be variation in the individual animal's susceptibility to the neutropenia-inducing activity of EABLS.  相似文献   
998.
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1000.
A Working Party of the European Association for Animal Production surveyed the breed comparison and crossbreeding trials which were being carried out in Europe. The survey summarizes the experimental work in the different countries and gives details on 86 separate projects concerned with breed and strain evaluation in pure and crossbreeding situations. The paper gives a general summary of the survey and recommendations on the methodology for future experiments. More detailed abstracts of the individual trials included in the survey are obtainable on request.  相似文献   
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