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Objectives – To develop a standardized technique for thrombelastography (TEG) analysis in healthy adult horses, with and without the ex vivo addition of tissue factor (TF) as an activator. To determine reference intervals for TEG parameters in the horse, and to determine if traditional coagulation tests correlate with TEG. Design – Prospective, observational. Setting – Veterinary teaching hospital. Animals – Twenty‐six healthy adult horses. Interventions – None. Measurements and Main Results – Thrombelastography with (TF‐TEG) and without (TEG) the addition of TF performed by 4 operators. Coagulation profiles (prothrombin time, activated partial thromboplastin time, platelet count, fibrinogen, antithrombin, and fibrinogen degradation products) were assessed in a subset of horses. Mean values (SD) for TEG parameters in healthy horses were: reaction time (R)=17.0 minutes (3.0 min), K time (K)=5.8 minutes (2.3 min), clotting rate (Ang)=42° (14°), maximum clot strength (maximum amplitude [MA])=60.3 mm (5.7 mm), CL30=97.0% (2.0%), LY30=0.8% (0.6%), CL60=92% (5.9%), LY60=3.2% (2.5%). Mean values (SD) for TF‐TEG parameters were: R‐TF=6.6 minutes (1.4 min), K‐TF=3.1 minutes (1.0 min), Ang‐TF=50.9° (9°), MA‐TF=62.3 mm (5.1 mm), CL30‐TF=97.8% (1.6%), LY30‐TF=0.6% (0.5%), CL60‐TF=90.8% (4.2%), and LY60‐TF=3.6% (1.9%). The addition of TF decreased R and K and increased Ang. TF‐TEG had a narrower SD for R, K, Ang, CL60 and LY60 compared with TEG. Interoperator differences were reduced by the addition of TF. Regression analysis indicated a positive relationship between MA and fibrinogen concentrations (P=0.02) and R‐TF time and prothrombin time (P=0.03). Conclusion – TF‐TEG using the described protocol may minimize variability in data obtained across institutions or users. However, due to the variability associated with different operators, it is recommended that each laboratory set up individual reference intervals with the personnel who will perform the assay, and that the assay protocols and data obtained are compared on a regular basis.  相似文献   
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Upper gastrointestinal examinations were performed in 11 unsedated ferrets and 4 ferrets sedated with ketamine and diazepam. Each animal received a 8-13 mL/kg body weight dosage of barium liquid (30% weight:volume). Radiographs were made immediately and at 5, 10, 20, 40, 60, 90, 120 and 150 min (mins) after the barium was administered. Gastric emptying began immediately. Mean total gastric emptying was longer in sedated ferrets (130 +/- 40 min versus 75 +/- 54 min); however, this difference was not statistically significant (p = 0.18). Small intestinal transit time was less than 2 h in all ferrets. The barium-filled small bowel was best visualized on the 20- and 40-min radiographs and did not exceed 5-7 mm in width. Flocculation of barium in the small intestine and adherence of barium to the stomach mucosa was seen in almost all animals. The longitudinal colonic mucosal folds in the colon were well visualized in the normal upper gastrointestinal study and aided in distinguishing small intestine from large intestine. The use of ketamine and diazepam sedation did not significantly affect the parameters evaluated in the upper gastrointestinal study series.  相似文献   
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Silent oestrus is an unsurmountable problem in the management of buffalo reproduction. In addressing this issue, we have earlier reported variation in the levels of urinary luteinizing hormone (LH) through the different phases of oestrous cycle with an extended window during the mid-oestrous phase. Based on this report, the present study is designed to assess the salivary LH levels in buffalo during the different phases of oestrous cycle. Bovine LH ELISA kit was used to determine the level of salivary LH. We observed a notable variation in salivary LH levels during the different phases of oestrous cycle. The maximum LH level, 39.07 mIU/ml, observed during oestrus, which was significantly (p < .05) higher than other consecutive phases. Altogether, the results showed a significant (p < .05) fold variation during oestrus compared with other phases. Therefore, the study convincingly shows that salivary LH has the potential of application in development of a modality for non-invasive oestrous detection in buffalo.  相似文献   
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A phosphorus-31 nuclear magnetic resonance imaging technique has been used to obtain information on phosphorus metabolites from different spatial regions of tissues in vivo. The technique for selection of planes through the tissue is based on phase-encoding of spin echoes and was used to obtain one-dimensional discrimination of phosphorus-31 spectra from different parts of the tissue simultaneously. Specimens were resolved into 16 distinct slices and a signal-to-noise ratio of about 20 to 1 was obtained in 1/2 hour. Results are presented for phantoms, rat legs, and gerbil heads.  相似文献   
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