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11.
OBJECTIVE: To compare gravimetric and colorimetric methods of quantifying surgical blood loss, and to determine if there is a correlation between preoperative hemostatic tests (buccal mucosa bleeding time [BMBT] and intraoperative blood loss). STUDY DESIGN: Prospective clinical study. ANIMALS: Dogs (n=15) admitted for cutaneous tumor excision, orthopedic procedure, or exploratory laparotomy. METHODS: Intraoperative blood loss was quantified by measuring irrigation fluid and weighing surgical sponges used for blood and fluid collection during surgery. Results of gravimetric measurements were then correlated to blood loss quantified using spectrophotometric analysis of hemoglobin (Hb) content. Hemostatic variables including BMBT were measured before surgery and compared with the calculated amount of blood loss. RESULTS: Blood loss quantified by gravimetric measurement showed a significant correlation with colorimetric determination of Hb content in surgical sponges and collected irrigation fluid (r=0.93, P<.0001). BMBT correlated weakly but significantly with intraoperative blood loss (r=0.56, P<.05). CONCLUSIONS: Quantifying intraoperative blood loss using spectrophotometric Hb analysis accurately assessed the amount of blood loss; however, it is a time-consuming procedure, primarily applicable as a research tool. Gravimetric evaluation of intraoperative blood loss was found to be an accurate method, which can be recommended for use in a clinical setting. CLINICAL RELEVANCE: Estimation of blood loss using a gravimetric method is accurate and applicable in the clinical setting and provides surgeons with a simple and objective tool to evaluate intraoperative blood loss.  相似文献   
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Detection of Cryptosporidium oocysts from goat kid faeces: comparison of a latex agglutination test with three other conventional techniques. A quantitative latex agglutination test (QLAT) with monoclonal antibodies for the detection of Cryptosporidium oocysts in faeces was compared with 3 other conventional techniques: Heine staining on faecal smears (HS) giving semi-quantitative results (scores from 1 to 5), sucrose flotation on diluted faeces (SF) with results expressed in oocysts/g of faeces (opg), direct ELISA (DE) giving qualitative results. Goat kid unconcentrated faecal samples (234) from 8 farms were processed according to the 4 techniques. Data were analyzed with Win Episcope 1.0 and Testview 1.1 softwares. The oocyst outputs ranged from 100 000 (detection limit for SF) to 200 millions opg (mean: 15.2 millions opg). A very good agreement was recorded between QLAT and HS, SF, DE: Kappa values ranged between 0.82 and 0.90. When considering the samples exhibiting oocysts (or not) as positive (or negative) using both HS and SF (n = 219), the sensitivity and specificity of QLAT were respectively 95.1 and 96.0%. The lack of sensitivity was observed in faeces harboring a few oocysts (< or = 200 000 opg, scores < or = 2) whereas the lack of specificity was only observed in 3 samples originating from the same farm. A significant correlation was calculated between the percentage of agglutination in QLAT and the number of oocysts in SF or scores in HS (Spearman correlation ranging from 0.45 to 0.48, p < 0.001). QLAT is a rapid, simple and reliable tool for routine detection of Cryptosporidium oocysts in faeces.  相似文献   
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To study the relation between serum complement levels and the chicken MHC (B) complex, complement haemolytic activity was measured in sera from hens from seven pure-bred B-typed White and one Brown Leghorn lines, and three ISA-Warren lines that had been divergently selected for antibody responses to sheep red blood cells (SRBC). Significant differences occurred in the serum haemolytic complement activities, both belonging to the classic (CPW) and the alternative (APW) pathways, among the 11 different haplotyped chicken lines. Hens with high CPW and high APW titres predominantly displayed the B2 or B21 haplotypes. Chickens with low CPW and APW were found in B14 and B15 haplotypes. Haplotype B14 appears to be different in complement levels when present into the pure-bred lines or into the ISA-Warren line selected for low antibody responses to SRBC. Otherwise, the presence of B21 in ISA-Warren line selected for high antibody responses to SRBC does not differ with the B21 in the inbred lines (except in the NL-line for CPW values). In general the haplotypes B2 and B21 are found in chicken lines with enhanced disease resistance, and the B15 haplotype has been connected with enhanced disease susceptibility. Our results suggest that levels of haemolytic complement activity, either from the classical or from the alternative pathways, may underlie part of the immunocompetence ascribed to the MHC (B) complex in chickens.  相似文献   
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OBJECTIVE: To describe a technique for thoracolumbar lateral corpectomy and to evaluate its use for treatment of chronic thoracolumbar disk disease in dogs. STUDY DESIGN: Retrospective study. ANIMALS: Fifteen dogs with signs of chronic thoracolumbar disk herniation. METHODS: After a dorsal or lateral approach to the spine, a lateral slot was created in 2 adjacent vertebral bodies on either side of the herniated disk and extruded/protruded material was removed. Data collected included history, duration of clinical signs, presurgical assessment of neurologic status, postsurgical neurologic status, complications, and outcome. RESULTS: Ambulatory capacity was maintained or regained, and neurologic status improved by 1 grade (3 dogs), 2 grades (8), 3 grades (2), or 4 grades (2). Eleven dogs were considered free of disease. A seroma in 1 dog was the sole complication observed. CONCLUSIONS: Lateral corpectomy permits relatively easy removal of protruded-extruded disk material from within the vertebral canal in chronic disk disease without further iatrogenic injury to the spinal cord. CLINICAL RELEVANCE: Lateral corpectomy is an alternative to dorsal decompression for treatment of ventral and lateroventral thoracolumbar chronic disk disease in dogs.  相似文献   
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For clinical isolates of bovine Mannheimia haemolytica and Pasteurella multocida, this study reports minimum inhibitory concentration (MIC) differences for tetracycline, oxytetracycline and doxycycline between cation‐adjusted Mueller‐Hinton broth (CAMHB), foetal bovine serum (FBS) and Roswell Park Memorial Institute (RPMI) medium. MICs were determined according to CLSI standards and additionally using five overlapping sets of twofold dilutions. Matrix effect: (a) free drug MICs and minimum bactericidal concentrations (MBC) for all drugs were significantly higher in FBS than in CAMHB for both pathogens (p < 0.001); (b) MICs and MBCs were higher for CAMHB and FBS compared to RPMI for P. multocida only. Net growth rate for P. multocida in CAMHB was significantly slower than in FBS and higher than in RPMI, correlating to MIC and MBC ranking. Drug effect: doxycycline MICs and MBCs were significantly lower (p < 0.001) in both CAMHB and FBS than tetracycline and oxytetracycline for both pathogens. Only for M. haemolytica were oxytetracycline MIC and MBC significantly lower than tetracycline, precluding the use of tetracycline to predict oxytetracycline susceptibility in this species. Determining potencies of tetracyclines in a physiological medium, such as FBS, is proposed, when the objective is correlation with pharmacokinetic data for dosage determination.  相似文献   
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Adrenalectomies for canine adrenal tumours are associated with peri-operative morbidity and mortality. Objectives of this study included assessing the prognostic value of tumour- or surgery-related variables in predicting peri-operative mortality and overall survival in dogs undergoing adrenalectomies for primary adrenal tumours as well as pre-treatment with phenoxybenzamine on survival to discharge with pheochromocytomas specifically. A multi-institutional retrospective cohort study was performed across nine institutions. Electronic medical record searches identified 302 dogs which met the inclusion criteria. Data collected included dog-related, tumour-related, treatment-related, surgery-related, and outcome variables. Univariate and multivariable logistic regression and cox proportional hazards models were used to identify variables associated with death prior to discharge and tumour-related survival. Overall, 87% of dogs survived to discharge with a tumour-related survival time of 3.96 years. Post-operative complications were reported in 25%. Increased surgical time (p = 0.002) and pre-surgical medical treatment other than phenoxybenzamine (p = 0.024) were significantly associated with increased peri-operative mortality while ureteronephrectomy (p = 0.021), post-operative pancreatitis (p = 0.025), and post-operative aspiration pneumonia (p < 0.001) were significantly associated with decreased overall survival. Phenoxybenzamine pretreatment had no effect on peri-operative mortality. Thirty-seven of 45 (82%) dogs with pheochromocytomas not pretreated survived to discharge, and 50 of 59 (85%) dogs with pheochromocytomas pretreated with phenoxybenzamine survived to discharge (p = 0.730). This study provides information on risk factors for death prior to discharge and tumour-related survival that may help guide clinical management and owner expectations. In addition, the study findings challenge the previously reported benefit of phenoxybenzamine for pretreatment of dogs undergoing adrenalectomies for pheochromocytomas.  相似文献   
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OBJECTIVE: To macroscopically, histomorphologically, and morphometrically compare uterine tissues obtained from nulliparous and multiparous dogs. ANIMALS: 12 dogs constituting 2 homogenous groups (7 nulliparous Beagles and 5 multiparous Beagles, each of which had at least 7 pregnancies). PROCEDURE: Serum concentrations of progesterone and estradiol-17beta were determined. Samples of uterine tissues were fixed, embedded in paraffin, and cut into serial cross sections. Morphometric analysis was performed on systematically selected trichrome-stained sections. RESULTS: Mean absolute volume of the uterine wall did not differ between groups. Volume of blood vessels was significantly higher and relative mean value for myometrial connective tissue was significantly lower in the multiparous dogs. Arteries in the myometrium of multiparous dogs had pronounced thickening of the intima (ie, pregnancy sclerosis) and a concomitant thinning of the smooth muscle layer (tunica media). Furthermore, the elastica interna of these arteries appeared to be disintegrating and was highly and irregularly folded. Adventitia of the myometrial veins in multiparous dogs contained numerous layers of elastic fibers; however, only a few layers were observed in the adventitia of corresponding veins in nulliparous dogs. CONCLUSIONS AND CLINICAL RELEVANCE: In this study, we documented that in contrast to other species, the uterus of nonpregnant dogs does not increase in size and volume even after at least 7 pregnancies. Furthermore, sclerotic alterations of uterine arteries are proof of at least 1 pregnancy. Results of this study may be useful in the evaluation of uterine diseases.  相似文献   
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