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1.
An orbital sialocele developed in a dog following enucleation for protracted glaucoma. This eye had historically been treated for keratoconjunctivitis sicca by parotid duct transposition approximately 5 years previously, and the duct was ligated distally at the time of enucleation. One month following enucleation, the dog presented with a fluctuant conical-shaped swelling ventrolateral to the orbital socket. Surgical exploration revealed a dilated, fibrotic distal portion of the previously transposed parotid duct, and saliva, within the enucleated orbit. The distal portion of the duct and saliva-containing tissues from within the orbit were excised. The remaining proximal normal portion of the parotid duct was re-routed into the oral cavity. Clinicopathologic and histologic examination of the excised orbital contents and dilated portion of duct revealed a sterile sample of saliva and moderate chronic periductal fibrosis. At a 6-month re-evaluation there was no evidence of recurrence of the sialocele, and the parotid duct was functional.  相似文献   
2.
冬季采暖保育猪舍送排风管道组合换气系统设计与评价   总被引:3,自引:2,他引:1  
为实现保育猪舍内局部环境通风调控,该研究设计一种垂直送排风管道组合换气系统。采用CFD(Computational Fluid Dynamics)技术对垂直管道通风模式下舍内的空气流场进行模拟,并以相对湿度和CO_2浓度作为输入变量建立通风模糊控制系统。模拟结果显示保育猪所在水泥地板区域风速保持在0.1~0.2 m/s。参照模拟结果,以猪栏为通风单元对保育猪舍通风系统进行改造,舍内气流不均匀性系数在0.1以下,表明采用该换气系统的保育猪舍通风均匀性较好;猪舍温度在21~25℃,相对湿度小于70%,NH_3浓度小于5mg/m~3,CO_2浓度小于1200mg/m~3,舍内各项环境参数适宜保育猪健康生长。系统运行功耗为270~1 150 W。现场测试与分析结果表明,该垂直送排风管道组合换气系统,可以精确控制猪舍环境,兼顾冬季猪舍通风与保温问题。  相似文献   
3.
为了解航速对船用喷水推进器内部流动特性的影响,以轴流式喷水推进器为研究对象,基于ANSYS-CFX软件,采用N-S基本方程和标准k-ε湍流模型,对以额定转速5500 r/min以及不同航速条件下的喷水推进器进行全流域定常数值模拟,得到了不同航速下喷水推进器叶轮叶片在不同切面上的压力载荷情况,各个过流部件上的湍动能变化规...  相似文献   
4.
喷雾降温风机风筒优化设计与试验   总被引:1,自引:0,他引:1  
为缓解高温热害对茶果树的影响,基于圆弧板型叶片模型设计了一种喷雾降温风机,并对风筒结构进行建模和动力学仿真。以出风口直径、进风段长度和出风段长度为试验因素,以风机出口总压和风速为试验指标,采用Design-Expert 8.0.6软件优化风筒结构参数。优化结果表明,各因素对出口总压和风速的影响由大到小依次为出风口直径、出风段长度、进风段长度。最优参数组合为出风口直径1 070 mm、进风段长度350 mm和出风段长度270 mm。选取WJ-7010、WJ-8010型喷嘴,利用优化后的风筒结构进行了风速试验和喷雾降温性能试验。风速试验表明,当风筒出风口直径和总长度分别为1 070、840 mm时,出风口风量为701.30 m~3/min,最大风速为16.00 m/s,有效送风距离约为55.00 m。喷雾降温性能试验结果表明,当使用WJ-8010型喷嘴时,与对照组相比,平均温度降低0.68~11.11℃,最大温差范围为1.80~13.90℃。在38℃高温环境下,喷雾降温风机在20 m范围内的降温幅度接近5℃,降温效果良好。  相似文献   
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6.
A 3-year-old Rhodesian Ridgeback was examined because of recurrent pancreatitis of 2 months duration. The dog had signs of abdominal pain and jaundice. Blood biochemical findings were consistent with extrahepatic bile duct obstruction, but on abdominal ultrasonography no cause of obstruction was identified. At surgery a pancreatic pseudocyst was found in the body of the pancreas. Cystoduodenostomy, cystic omentalisation and biliary diversion resulted in excellent long-term recovery.  相似文献   
7.
The purpose of this study is to report our initial experience with the use of spring coils to close the patent ductus arteriosus in the dog. There are few large-patient series reported in the veterinary literature. Coil closure was attempted in 15 dogs (median weight, 6.5 kg; range, 1.2 to 38.7 kg) presenting with a patent ductus arteriosus between May 1997 and May 1999. Arterial catheterization followed by angiography was used to decide if coil placement was adequate. A 5- or 8-mm embolization coil, depending on the angiographic diameter of the ductus, was delivered, with 1 loop in the pulmonary arterial side and the remainder of the coil in the aortic side of the duct. Additional coils were used if a residual shunt was present, and closure was confirmed by aortography. Patients were discharged the day after the procedure. Successful coil closure, without residual shunt on angiography, was achieved in 11 of 13 dogs in which coils were released. In 6 dogs, a coil embolized to the pulmonary artery. Four of these dogs had successful closure with multiple coils, and 2 others had surgery. None of these dogs experienced adverse effects. In 2 dogs with conical patent ductus arteriosus >5 mm in minimal diameter, coil closure was not done. We conclude that the patent ductus arteriosus size and anatomical shape are crucial in deciding whether coil closure is the method of choice. In selected cases, coil closure represents an elegant alternative to surgical ligation. Although pulmonary embolism occurred commonly, it did not cause any obvious clinical problem.  相似文献   
8.
ObjectiveTo describe the characteristics and outcomes of transcatheter patent ductus arteriosus (PDA) occlusion after incomplete or aborted surgical ligation in dogs and cats.AnimalsTwelve client-owned animals (11 dogs and one cat).Materials and methodsThis retrospective study describes data from animals with aborted or incomplete surgical PDA ligation that subsequently underwent transcatheter closure using endovascular methods. Patient demographics, reason for incomplete or aborted surgery, complications, and method of transcatheter occlusion were recorded. Data are presented as mean ± standard deviation or median (interquartile range), where appropriate.ResultsFor all cases, median age at surgery was 12.2 months (4.9–15.1 months) and at catheterization was 15.4 months (8.9–21.9 months), with 79 days (29–209 days) between surgical and interventional procedures. Median weight at catheterization was 4.5 kg (2.5–12.6 kg). Reasons for failed surgical ligation included hemorrhage during ductal dissection in seven dogs, residual flow in four dogs, and inability to identify the ductus in one cat. Transcatheter closure was successfully performed using a canine duct occluder in eight dogs, transarterial coil embolization in two dogs, and transvenous coil embolization in one dog and one cat. Metallic hemoclips partially obscured angiographic findings in three cases with prior surgical hemorrhage but did not prevent transcatheter closure. In all cases, ductal flow was successfully attenuated, with no or trace residual shunting on angiography and complete occlusion the following day on echocardiography.ConclusionsWhen surgery is unsuccessful, either owing to hemorrhage or residual flow, transcatheter closure of PDA is feasible, even in small patients.  相似文献   
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10.
利用氨基酸自动分析仪和蛋白质电泳技术,对呼和浩特地区胆石症患者胆汁做了主要氨基酸的测定及蛋白质电泳分析。报道了胆石症患者胆囊胆汁中16种氨基酸的含量;蛋白质总量中以脂肪族氨基酸含量最大;酸性氨基酸大于碱性氨基酸,两者间的差异显著。胆石症患者胆囊胆汁和肝胆汁经蛋白电泳分析结果与慢性胆囊炎患者血清蛋白电泳的变化规律相同。即慢性胆囊炎患者血清的电泳分析中白蛋白含量减少;α_2、α_2、β、γ球蛋白含量增加。此测定结果对胆石症的研究及防治提供了新的线索。  相似文献   
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