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This paper provides a bird’s-eye perspective of the general principles of stem-cell therapy and tissue engineering; it relates comparative knowledge in this area to the current and future status of equine regenerative medicine.  相似文献   
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A 12-year-old, female mangrove snake (Boiga dendrophila melanota) was presented with a 1-month history of anorexia, lethargy, and progressive distention of the caudal coelomic cavity. Based on ultrasonographic and cytological examination, an ovarian neoplasia was considered to be the presumptive antemortem diagnosis. Histological examination confirmed the diagnosis of a granulosa cell tumor (GCT) with metastatic tumors in the coelomic fat bodies. Four months following oophorectomy and surgical removal of the distant metastasis, the snake was euthanized because of sudden onset of lethargy, cardiomegaly, and dyspnea. Postmortem examination revealed the presence of metastatic tumors in the lung, liver, and kidneys. Primary ovarian neoplasms are relatively rare in reptiles. Although GCTs have been documented in snakes, definitive diagnosis is typically determined through postmortem histopathological examination. The present case describes a suitable antemortem diagnostic approach of a malignant GCT in a mangrove snake with distant metastases.  相似文献   
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The positive contrast gastrointestinal study is a common non‐invasive diagnostic technique that does not require anesthesia and enables good visualization of the digestive tract. Radiographic anatomy and reference intervals for gastrointestinal contrast transit time in inland bearded dragons (Pogona vitticeps) were established using seven animals administered 15 ml/kg of a 35% w/v suspension of barium by esophageal gavage. Dorso‐ventral and lateral radiographic views were performed at 0, 15, 30 min, 1, 2, 4, 6, 8, 12 h, and then every 12 h up to 96 h after barium administration. Gastric emptying was complete at a median time of 10 h (range 4–24 h). Median jejunum and small intestinal emptying times were 1 h (range 30 min–2 h) and 29 h (range 24–48 h), respectively. Median transit time for cecum was 10 h (range 8–12 h). Median time for contrast to reach the colon was 31 h (range 12–72 h) after administration. Results were compared to those obtained in other reptilian species. This technique appeared safe in fasted bearded dragons and would be clinically applicable in other lizard species.  相似文献   
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Acid mine drainage from Contrary Creek flows into an entire arm of Lake Anna. Much of the acid inflow is neutralized by bacterial sulfate reduction in the lake sediments. We developed a simple model to track the seasonal fate and mass transport of sulfate and alkalinity along the acidified arm. The loss of sulfate from the water column was characterized by a first-order decay reaction. A gain in alkalinity due to sulfate removal was also incorporated in the model. In addition, CO2 acidity and pH in the water column were calculated. The model was calibrated with data collected in 1983 and 1984. Model sensitivity runs were conducted to demonstrate the importance of sulfate reduction in the system.  相似文献   
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Quantitative determinations of the four black currant anthocyanins, cyanidin 3-O-beta-glucoside, cyanidin 3-O-beta-rutinoside, delphinidin 3-O-beta-glucoside, and delphinidin 3-O-beta-rutinoside, were achieved in black currant juices by a rapid and sensitive high-performance liquid chromatographic (HPLC) method. The method was validated, and quantification of anthocyanins in 13 commercially available black currant beverages was demonstrated. To optimize the handling of anthocyanin-containing samples, the pH-dependent stability of the anthocyanins was investigated. Four anthocyanins were incubated for 24 h in aqueous solutions at 13 different pH levels between 0.6 and 5.2, after which the samples were analyzed by HPLC. More than 90% of each anthocyanin remained intact up to pH 3.3. At pH 3.8 a local minimum in stability was detected, and at pH >4.5 the stability rapidly decreased. The antioxidant capacity of all 13 black currant juices was investigated by TEAC and FRAP, and the antioxidant potential of both the anthocyanin and the vitamin C contents in the juices was evaluated. This indicated that <70% of the antioxidant capacity of the juices could be attributed to the anthocyanin content or to vitamin C, signifying that other very potent antioxidants are present in commercial black currant juices.  相似文献   
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Tests have been developed to enable growers to choose pesticides that spare the natural enemies of pests. The test for Aleochara bilineata is carried out in glass cells, and for Phytoseiulus persimilis on detached bean leaves; both expose the laboratory-reared arthropods to a fresh, uniform pesticide residue under standardised conditions. The duration of the tests is 1 and 2 weeks, respectively. In both tests reproduction during the experimental period is measured, and the reduction caused by the pesticide is calculated by comparison with a water-treated control.  相似文献   
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