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31.
A tumor of the third eyelid gland was diagnosed in a 13 year old female Chihuahua. Histopathology of the excised tissue revealed an apocrine adnexoma with squamous metaplasia. The literature regarding prolapse and tumors of the third eyelid gland was reviewed. No case with similar morphology to this tumor was described to our knowledge.  相似文献   
32.
The objective was to evaluate the nutritive value of short-cutting cycle, high temperature-dried (SCCHTD) alfalfa compared to timothy hay. This was achieved by carrying out 4 x 4 Latin Square digestibility trial using 4 Thoroughbred (one three-quarter Thoroughbred) horses (mean liveweight, 531 kg). The four dietary treatments were 0AA (timothy hay only), 33AA (0.33 alfalfa: 0.67 timothy hay), 67AA (0.67 alfalfa: 0.33 timothy hay) and 100AA (alfalfa only). Digestibility data were obtained by using acid-insoluble ash to estimate apparent digestibility coefficients of nutrients. Rate of passage of the feedstuff was determined using chromium-mordanted hay. Plasma triglyceride and cholesterol concentrations were estimated. The digestibilities of organic matter (0.63), energy (0.57) and crude protein (0.74) of the alfalfa were significantly (P less than 0.001) higher than those for the hay (0.45, 0.43 and 0.36 respectively). The fibre components of alfalfa and hay were digested to the same extent but the ether extract of alfalfa was less well digested. Alfalfa saponins had no consistently significant effects on plasma cholesterol and triglyceride values but may contribute to the negative digestibility of alfalfa ether extract. We conclude that SCCHTD alfalfa is of much higher nutritive value than timothy hay when fed to Thoroughbred horses.  相似文献   
33.
Antibody responses to a commercial avian encephalomyelitis virus (AEV) vaccine administered by different routes were measured by an enzyme-linked immunosorbent assay (ELISA). Responses to single doses of vaccine administered by the ocular route to 10% of a flock were comparable with those obtained when all birds received a single dose in the drinking water. However, ocular vaccination of 5% of the flock resulted in significantly lower responses than those obtained when 10% were vaccinated. Maternal antibody was shown by the ELISA to persist in chickens from vaccinated flocks for up to 21 days after hatching. Day-old chickens with serum absorbances of < 0.3 at 492 nm, as determined by the ELISA, were shown to be susceptible to intracerebral challenge with the neurotropic Van Roekel strain of AEV.  相似文献   
34.
Suckling rats were inoculated with a group B rotavirus to determine the progression of the morphologic changes induced in the intestine by this virus. Several changes were observed by light microscopy 1 day after viral inoculation: shortening of small intestinal villi, villous epithelial necrosis, and villous epithelial syncytia. The lesions were most often present in the distal small intestine, although other small intestinal segments were affected to a lesser degree. By day 3 post-inoculation, epithelial necrosis, and syncytia were no longer present; however, the villous epithelium was disorganized and irregularly vacuolated, and intestinal crypt epithelium was hyperplastic. Alterations in villous height to crypt depth ratios were present in portions of the small intestine for the remainder of the 12-day study period. Epithelial syncytia appeared to form by the breakdown of the lateral interdigitating membranes of the absorptive villous epithelium. Viral particles, abundant in the syncytia, appeared to form from amorphous or reticular arrays of viral precursor material. Group B rotaviral antigens, as detected by indirect immunofluorescence, were present in large amounts in the small intestinal villous epithelium only on the first day after viral inoculation. These studies show that two important diagnostic features of group B rotaviral infections of rats, epithelial syncytia and viral antigen as determined by immunofluorescence, are present only on the first day of disease. These findings should be taken into consideration when attempting to diagnose disease induced by this agent.  相似文献   
35.
Ovine-derived fibroblasts were used to validate an insulin-like growth factor I (IGF-I) membrane-receptor binding assay system. Competitive binding using fibroblasts revealed that half-maximal inhibition of 125I-IGF-I binding by IGF-I was 2.3 nM. SDS-polyacrylamide gel electrophoresis analysis of specific protein-associated 125I-IGF-I was consistent with the migration of 125I-IGF-I-labeled Type I IGF receptor alpha-subunits at Mr 133,000 daltons. Further, the efficiency of two cell solubilization methods was examined and time-dependent binding equilibrium was determined for the membrane assay system. Satellite cell-derived myotubes were subsequently isolated from primary satellite cell cultures established from the semimembranosus muscles of high and low efficiency-of-gain (EOG) Targhee rams, and IGF-I receptor dynamics were measured. A membrane competitive binding study revealed that half-maximal inhibition of 125I-IGF-I binding was achieved by 1-ng IGF-I for low, and 10-ng IGF-I for high, EOG myotube membrane preparations. Kd values were similar between the high EOG (4.78 nM) and low EOG (2.95 nM) groups; however, receptor concentrations (Bmax) appeared to differ between groups. High EOG membrane receptor Bmax was 3.88 pmole/micrograms protein (19.87 pmole/micrograms DNA), whereas low EOG membrane receptor Bmax was 1.22 pmole/micrograms protein (9.28 pmole/micrograms DNA). These preliminary findings support the hypothesis that genetic selection for EOG results in altered satellite cell responsiveness to IGF-I.  相似文献   
36.
By using flow cytometry, a retrospective analysis of the DNA content of 40 primary canine mast cell tumors and seven lymph nodes that contained metastatic mast cell tumor from 44 dogs of various breed, sex, and age was performed on formalin-fixed, paraffin-embedded samples of the tumors and nodes. These samples were chosen according to the following criteria: samples contained sufficient well-preserved tumor tissue in the paraffin block for processing, sufficient patient history data were available, clean and homogeneous cell suspensions were obtained after processing, and interpretable DNA histograms were produced on analysis. The ploidy data obtained were compared with the histopathologic grade, the anatomical site of occurrence, the clinical stage of the tumors, and the survival of the dogs. Over 70% (29/40) of the mast cell tumors were diploid. Three metastatic mast cell tumors in lymph nodes had the same ploidy status as their corresponding primary tumors. In five dogs, mast cell tumors from multiple sites in each dog displayed similar ploidy status. Of 26 dogs evaluated for survival times, 69% (18/26) had diploid tumors and 31% (8/26) had aneuploid tumors. When numbers of diploid versus aneuploid tumors were compared, no significant difference was found between any two grades, clinical stages, or anatomic sites. A significant difference (P = 0.02) was found, however, between aneuploid and diploid tumors when comparing Stage I and non-Stage I disease. The Kaplan-Meier survival plot indicated a tendency towards an increased survival within the first year in dogs with diploid versus aneuploid tumors (P = 0.06).  相似文献   
37.
Affinity chromatography on heparin sepharose was used to identify 2 lipolytic enzymes in heparinized plasma from horses. One enzyme was typical of hepatic triglyceride lipase (HTGL), because it was resistant to inactivation by high concentrations of NaCl, and it did not require the addition of serum for activity. The other enzyme was identified as lipoprotein lipase (LPL), because of its inactivation at NaCl concentrations in excess of 0.2M, and its dependency on addition of serum as a source of apolipoprotein C-II activator. The enzymes were purified by 347-(HTGL) and 442- (LPL) fold, with yields of 54 and 58%, respectively. The partially purified enzymes were used to design incubation conditions that gave optimal activities for each enzyme in vitro. A selective assay was then developed for direct measurement of LPL and HTGL activities in heparinized plasma from horses. Analysis of HTGL took advantage of the almost complete inactivation of LPL when serum cofactor was excluded from the assay at the NaCl concentration that gave optimal HTGL activity. Prior incubation of heparinized plasma with sodium dodecyl sulfate to inhibit HTGL was necessary for measurement of LPL, because HTGL retained 67% of its activity at the NaCl concentration required for optimal LPL activity. Activity of each enzyme was measured in heparinized plasma from 12 Shetland ponies. The mean activity +/- SD for LPL was 3.22 +/- 1.04 mumol of fatty acids/ml of heparinized plasma/h (mumol of FA/ml/h. The mean activity for HTGL was 4.9 +/- 1.56 mumol of FA/ml/h. The performance of the assay was assessed by replicate analysis of pools of each enzyme with high and low activities.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
38.
Chickens were given various fowlpox vaccines on food pellets--a commercial vaccine (strain M), and the same strain after a single passage on chorio-allantoic membrane or in chicken embryo fibroblasts. All three oral vaccines induced antibodies at levels similar to those induced by commercial strain M administered to the wingweb. The oral vaccine derived from chorio-allantoic membrane gave protection similar to that obtained with vaccine administered by the wingweb, but this required a thousandfold more virus.  相似文献   
39.
40.
In this clinical study, a diaphragmatic peritoneo-pericardial hernia in an eight month-old Persian cat is reported. The diagnostic procedure is described, and the clinical symptoms and diagnostic possibilities are discussed.  相似文献   
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