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991.
Molecular investigation of 16 strains, conventionally identified to be Malassezia pachydermatis, isolated from dogs in Japan was carried out by random amplification of polymorphic DNA (RAPD) and chitin synthase 2 (CHS2) gene sequence analyses. The RAPD band patterns of 13 clinical isolates were identical to that of standard strain of M. pachydermatis (CBS-1879). The other three clinical isolates were different from the standard strain of M. pachydermatis in RAPD patterns, and two of the three isolates were identical. About 620 bp genomic DNA fragments of the CHS2 gene were amplified from the same 16 clinical isolates of M. pachydermatis by polymerase chain reaction (PCR) and sequenced. The phylogenetic analysis of the nucleotide sequences of CHS2 gene fragments of the 16 clinical isolates revealed that the 13 strains were genetically very close to the standard strain of M. pachydermatis and the other two isolates were genetically close to the standard strain of M. furfur rather than M. pachydermatis. The remaining one isolate was phylogenetically distinct from all the seven Malassezia species reported so far. 相似文献
992.
993.
C. D. McMahon L. T. Chapin K. J. Lookingland R. P. Radcliff H. A. Tucker 《Domestic animal endocrinology》1999,17(4):181-447
Secretion of growth hormone (GH) is reduced for several hours after feeding when access to feed is restricted to a 2-hr period each day. We hypothesized that increased secretion of insulin after feeding inhibits release of GH from the anterior pituitary gland. Our objectives were to determine whether: 1) alloxan prevents concentrations of insulin from increasing after feeding steers; 2) concentrations of GH remain high after feeding alloxan-treated steers; and 3) GH-releasing hormone (GHRH) stimulates greater release of GH in alloxan-treated, than in control, steers after feeding. Steers were injected iv with either saline (control) or with alloxan (110 mg/kg) (n = 4 per group). Concentrations of insulin were not different (P = 0.61) between control and alloxan-treated steers before feeding (87.5 +/- 33.6 pmol/l). However, alloxan prevented insulin from increasing (P < 0.001) after feeding (131.8 pmol/1) compared with control steers (442.0 pmol/l) (pooled SEM = 47.5). Overall, GH was higher (P < 0.05) in alloxan-treated (6.4 ng/ml) than in control steers (3.7 ng/ml) (pooled SEM = 0.7), but GH decreased (P < 0.001) after feeding in both groups. Iv injection of GHRH stimulated release of GH 1 hr before, but not when injected 1 hr after feeding (P < 0.001). In addition, net areas under the GH curve were not significantly different between control and alloxan-treated groups. We conclude that increased concentrations of insulin after feeding do not mediate feeding-induced suppression of GH secretion in steers. 相似文献
994.
The use of chance-corrected agreement to diagnose canine compulsive disorder: an approach to behavioral diagnosis in the absence of a 'gold standard'. 下载免费PDF全文
This study assessed the diagnostic accuracy of formal diagnostic criteria for canine compulsive disorder (canine CD). Canine CD is a syndrome of abnormal behaviors that are believed to result from conflict or frustration. Differential diagnoses include normal conflict behavior and learned behavior. In studies of canine CD, confidence in the diagnosis comes with knowing the accuracy of the diagnostic method. This accuracy may be quantified as the chance-corrected agreement between the diagnostic method and a 'gold standard' diagnostic test. The present study examined the agreement between diagnoses of canine CD made by an expert (the 'gold standard') and by using formal diagnostic criteria. The owners of 84 dogs suspected of having CD received 2 telephone interviews. The first utilized a detailed, pre-tested questionnaire; a dog was then diagnosed with CD if the behavioral history met 7 diagnostic criteria. The second interview was given by a behavioral expert whose diagnosis was based on personal experience. The interviewers were blind to each other's diagnoses. The chance-corrected agreement between diagnoses was minimal (kappa = 0.02) and disagreement was associated with 3 of the formal criteria: a history of conflict or frustration, an increase in the number of contexts that elicit the behavior, and an increase in the daily frequency of the behavior. Reasons for the disagreement include the order of the interviews, response biases, the setting of the interviews, and, possibly, the diversity of the behaviors associated with canine CD. To the authors' knowledge, this type of study is the first in clinical ethology to address validation of the diagnostic method. The results indicate 3 developmental aspects of canine CD that should be examined in future work. 相似文献
995.
996.
997.
J A Robinson C M Marr V B Reef R W Sweeney 《Journal of the American Veterinary Medical Association》1992,201(10):1593-1598
A Standardbred filly was admitted for evaluation of pleuritis and pneumonia. Heart rate was 80 to 120 beats/min, and the pulse was barely palpable. Thoracic and abdominal ultrasonography and echocardiography revealed substantial pericardial effusion with cardiac tamponade, fibrinous pericarditis, pleural effusion, and ascites. Initial electrocardiography revealed normal sinus rhythm with decreased amplitude of the QRS complexes consistent with pericardial effusion. Following thoracentesis, echocardiogram-guided pericardiocentesis was performed. Bacterial culture yielded no growth from any of the fluids, and bacteria were not seen on cytologic examination. Initial treatment included broad-spectrum antibiotic treatments, IV fluid therapy, and anti-inflammatory agent administration. On the basis of negative culture results, an immune-mediated cause was considered, and dexamethasone was instituted in a decreasing dosage regimen. Pericardial effusion, ventral edema, and ascites began to resolve within 3 days after beginning dexamethasone treatment. Thirty days following discharge, the filly was reexamined, and at that time, the prognosis for athletic performance was considered good so the horse was returned to race training. The final diagnosis in this case was idiopathic, effusive, nonconstrictive pericarditis with tamponade. Early identification, clinical understanding, and application of knowledge of the pathophysiologic mechanisms of pericarditis in horses, combined with use of diagnostic aids such as ultrasonography and aggressive therapy consisting of effusion drainage, pericardial lavage, antibiotics that penetrate the pericardium, and corticosteroids when indicated are critical for a successful outcome in horses with pericarditis. 相似文献
998.
Synchronization of estrus in dairy goats given norgestomet and estradiol valerate at various stages of the estrous cycle. 总被引:1,自引:0,他引:1
K N Bretzlaff L C Nuti R G Elmore S A Meyers J N Rugila S P Brinsko T L Blanchard P G Weston 《American journal of veterinary research》1992,53(6):930-934
Dairy goats were given subcutaneous implants with 3 mg of norgestomet (NOR) and IM injections of 0.625 mg of estradiol valerate and 0.375 mg of norgestomet on day 0 of the estrous cycle (estrus; NOR 0, n = 18), on postestrus day 4 (NOR 4, n = 18), or on postestrus day 11 (NOR 11, n = 15). Ear implants were removed after 9 days. Mean (+/- SE) hours from removal of ear implants to onset of estrus and proportion of goats responding were 36 +/- 3.8 and 83%, 33 +/- 4.0 and 61%, and 36 +/- 2.7 and 93% for groups NOR 0, NOR 4, and NOR 11, respectively. There were no significant differences between treatment groups in time to onset of estrus. The percentage of goats in group NOR 11 that had signs of estrus was significantly greater than the percentage of goats in group NOR 4. Of the goats in groups NOR 0, NOR 4, and NOR 11 that had signs of estrus, 53, 55, and 86%, respectively, had onset of behavioral estrus between 24 and 48 hours after implant removal. All goats that had signs of estrus had onset of behavioral estrus between 12 and 72 hours after implant removal. Mean (+/- SE) hours from removal of ear implants to time of peak concentrations of luteinizing hormone (LH) were 49 +/- 4.1, 49 +/- 3.8, and 49 +/- 4.0 for groups NOR 0, NOR 4, NOR 11, respectively (not different). The percentage of goats in group NOR 11 that had LH peaks was significantly greater than the percentage of goats in group NOR 4.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
999.
1000.
Estrogen and progesterone receptor status of mammary carcinomas and correlation with clinical outcome in dogs. 总被引:3,自引:0,他引:3
E A Sartin S Barnes R P Kwapien L G Wolfe 《American journal of veterinary research》1992,53(11):2196-2200
Estrogen and progesterone receptors (ER, PR) were measured in cytosol fractions from 18 primary canine mammary carcinomas by use of biochemical assays. One or both receptors were detected (> 10 fmol/mg of cytosol protein) in 11 tumors: 5 ER and PR; 2 ER only; 4 PR only. Mean cytoplasmic receptor concentrations (fmol/mg of cytosol protein) were 22.8 +/- 2.9 (SEM) for ER and 51.0 +/- 10.3 for PR in tumors containing ER and PR, 28.8 +/- 12.1 for ER in tumors containing only ER and 13.2 +/- 1.5 for PR in tumors containing only PR. Estrogen or progesterone receptors or both were identified in 6 of 9 tubular adenocarcinomas, 4 of 5 papillary adenocarcinomas, and 1 of 1 squamous cell carcinoma. These receptors were not identified in solid carcinomas (n = 2) or a single spindle cell carcinoma. Although the number of cases was limited, survival times of dogs tended to be longest in those with tumors containing ER alone or in combination with PR, intermediate in those with tumors containing only PR, and shortest in those with tumors without ER or PR. A correlation was not apparent between receptor status and age, presence of ovaries, tumor size, or histologic classification of the tumor. In the analysis of this series, the extent of surgery (mastectomy of the involved gland vs unilateral or bilateral mastectomy) did not appear to influence the outcome of the disease, and metastasis to regional lymph nodes did not appear to be a reliable prognostic indicator. 相似文献