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221.
Corneal diseases are common in domestic rabbits. It is important to carefully evaluate the cornea and the entire eye when rabbit present with clinical signs such as squinting, tearing, or conjunctival hyperemia. Complete ophthalmic examination and general physical examination should be performed on all rabbits with corneal disease. Important diagnostic testing include culture and sensitivity, cytology, and fluorescein staining. Breed predispositions do not occur for most corneal problems, although some diseases are selected genetically in research rabbits. Corneal disease can be a primary condition or can occur secondary to other ocular or systemic disease.  相似文献   
222.
William R.  Widmer  DVM  MS  William E.  Blevins  DVM  MS  Samuel  Jakovljevic  DVM  MS  Robert F.  Teclaw  DVM  PhD  Connie M.  Han  RVT  Cheryl D.  Hurd  RVT 《Veterinary radiology & ultrasound》1992,33(6):327-333
In a blind clinical trial, adverse effects after iohexol and iopamidol myelography were evaluated in 151 dogs. Eighty-one dogs were given iohexol (240 mgI/ml) and 70 dogs were given iopamidol (200 mgI/ml) by pre-determined assignment. Each dog was evaluated postmyelographically for seizures, hyperthermia, prolonged recovery from anesthesia and intensification of pre-existing neural signs. Myelographic quality was evaluated with a subjective scoring method. In comparing iohexol and iopamidol groups, there was not a statistically significant difference in the incidence of adverse effects or in myelographic quality. Iopamidol and iohexol appeared to be equally efficacious for routine canine myelography.  相似文献   
223.
The objectives of this study were to examine effects of a beta-adrenergic agonist (cimaterol) on growth and muscle development in rabbits and to examine cimaterol's effects on myofibrillar protein degradation (MPD) and on activities of several proteolytic enzymes including the calcium-dependent proteinases (CDP). Twelve New Zealand White rabbits were assigned to either control diets or to diets containing cimaterol for 35 d, after which they were killed and effects on performance and tissue weight gains were determined. Urine was collected from d 21 through 28 from each rabbit for assessment of N tau-methylhistidine (NMH) excretion. Cimaterol increased rates of gain, efficiency of gain and skeletal muscle weights. Enhancement in muscle weight was associated with an increase in total DNA and with a reduction in NMH. Cimaterol did not affect activities of cathepsin B, cathepsin D or neutral serine proteinase, but it reduced activities of the millimolar and micromolar forms of the CDP by 58 and 57%, respectively, and it reduced activity of the inhibitor of the CDP (calpastatin) by 52%. Cimaterol-dependent myofibrillar protein accretion was likely mediated, at least in part, by a reduction in MPD. The change in MPD was associated with a reduction in muscle CDP activities. Cimaterol-dependent muscle hypertrophy therefore may involve changes in calcium-dependent proteolysis of myofibrillar proteins. The significance of the effects of cimaterol on calpastatin activity is not known.  相似文献   
224.
A 14-year-old domestic shorthaired cat was presented because of swelling of the digits and lameness. A solitary lung mass was observed on thoracic radiographs. Clinical and pathological evaluation confirmed a primary pulmonary squamous cell carcinoma metastatic to a single digit on each foot. Other metastatic lesions were present in the left popliteal lymph node and in the left iliac vein.  相似文献   
225.
This study comprised 48,931 litters in 89 sow herds. During the study (1976-82) weaning age decreased from approx. 42 days to approx. 30 days. The mean incidence of post-weaning diarrhoea was 6.0% of litters weaned, with little variation by year but with considerable variation among herds. Within the individual herd increased incidence occurred over limited periods, probably associated with specific infections. Litters with diarrhoea during the suckling period had increased risk of post-weaning diarrhoea. The incidence of post-weaning diarrhoea increased with litter size at weaning. Thus, a litter of 11-12 piglets at weaning had 1.2 times higher risk than litters with 8-10 piglets. In contrast to pre-weaning diarrhoea, there was no association between parity of the sow and diarrhoea in the litter after weaning. Litters weaned below 2 weeks of age had a 2-fold risk of developing diarrhoea after weaning and a 2.4-fold higher mortality rate than did litters weaned at 6-7 weeks. Similarly, litters weaned at an individual piglet weight below 3 kg bodyweight had a 3-fold higher risk of developing diarrhoea after weaning and a 5-fold higher mortality rate than did pigs from litters weaned at a bodyweight of 7-8 kg. The incidence of post-weaning diarrhoea decreased with increasing herd size. Piglets from litters with post-weaning diarrhoea had reduced weight gains after weaning and were 2.3 days older at 25 kg bodyweight than piglets from non-diarrhoeic litters. Likewise, diarrhoea after weaning was associated with an increased incidence of diseases of the skin and respiratory tract. Thus the risk of contracting respiratory disease was 4 times greater in diarrhoeic litters.  相似文献   
226.
Toxicity of Haemophilus pleuropneumoniae to porcine lung macrophages   总被引:10,自引:0,他引:10  
Viable Haemophilus pleuropneumoniae bacteria were toxic for porcine alveolar macrophages in vitro. This cytotoxic effect proved to be dose-related. A cell-free extract of H. pleuropneumoniae, heat-killed bacteria, and a Pasteurella multocida field strain were nontoxic. When macrophages were cultured with H. pleuropneumoniae bacteria in a ratio of 100 macrophages to six bacteria, ultrastructural signs of cellular degeneration were observed within 1 h. This degeneration was observed in macrophages with or without phagosomes containing H. pleuropneumoniae. A cytotoxic substance was filtered from a H. pleuropneumoniae culture in Eagle's minimal essential medium supplemented with Earle's salts (EMEM) and 10% foetal calf serum that was incubated for 10 h at 37 degrees C. This substance was destroyed by heating at 65 degrees C for 30 min. Macrophages were less susceptible to the toxic effect of H. pleuropneumoniae when serum of convalescent pigs was added.  相似文献   
227.
This article presents important clinical pharmacologic aspects of drug therapy during pregnancy. It reviews the potential adverse effects on the mother and conceptus caused by drugs and includes specific recommendations for therapy. Extensive tables are included that list drugs that are safe and those that are contraindicated during pregnancy.  相似文献   
228.
229.
Blood samples from 331 greyhounds in the Hunter Valley and nearby coastal areas of New South Wales were examined for microfilariae using a filtration technique. Species were identified by histochemical staining; 10.9% of the greyhounds were infected with Dirofilaria immitis and 3.6% with Dipetalonema reconditum. The prevalence of infection of both species was significantly greater in summer than in winter (p = less than 0.05). Infection with D. immitis was correlated with differences in age, sex, bodyweight and coat colour, and a reported lack of stamina and the presence of a cough. No significant association was found. Diethylcarbamazine citrate was used for prophylaxis in 8.8% of all the greyhounds examined.  相似文献   
230.
Three commonly used keratin monoclonal antibodies (MAB)--AE1:AE3, CAM 5.2, and MAK-6--were compared with routinely used cytokeratin antibody. The expression of these antibodies was analyzed in several tissues obtained from clinically normal dogs and in a variety of neoplasms from dogs. Using appropriate enzymatic digestion, paraffin-embedded tissues processed in routine manner retained their typical keratin expression. Differentiated and poorly differentiated epithelial neoplasms, lymphomas, and melanomas were studied by use of the avidin-biotin-peroxidase technique. All 4 of the aforementioned antibodies had similar staining profiles. Of 3 anaplastic carcinomas, 2 had positive reaction to all 4 antibodies. All lymphomas, plasma cell tumors, and amelanotic melanomas had negative reaction to MAK-6, CAM 5.2, AE1:AE3, and cytokeratin MAB. Three basal cell epitheliomas had positive reaction to all 4 antibodies, whereas 1 basal cell tumor with a solid pattern had negative staining reaction. Two carcinoids had negative reaction to all markers and 1 of 2 malignant chemodectomas and 1 transitional cell carcinoma had staining reaction to only AE1:AE3 MAB. Comparing the 4 antibodies, use of AE1:AE3 MAB produced the strongest staining intensity followed by cytokeratin, MAK-6, and CAM 5.2 MAB. All 4 antibodies had low background staining. In conclusion, AE1:AE3 and MAK-6 MAB are as useful as cytokeratin MAB for identification of poorly differentiated epithelial neoplasms in dogs and cats.  相似文献   
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