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91.
Canine reticulocyte hemoglobin content (RET‐He) in different types of iron‐deficient erythropoiesis 下载免费PDF全文
92.
ALLISON L. ZWINGENBERGER MATHIEU SPRIET GERALDINE B. HUNT 《Veterinary radiology & ultrasound》2011,52(4):444-447
Severe portal vascular anomalies have been reported previously accompanying azygos continuation of the caudal vena cava, polysplenia, and situs anomalies in dogs and people. Three dogs with portal vascular anomalies were identified by means of CT angiography as having portal vein aplasia with portal insertion into the caudal vena cava, azygos continuation of the caudal vena cava, and interruption of the pre‐hepatic caudal vena cava. This information confirms that complex embryological defects may occur in patients presenting for congenital portosystemic shunt, and that CT angiography is a non‐invasive method of completely evaluating these potentially non‐surgical portal vascular anomalies. 相似文献
93.
针对强风时自动集沙仪测量精度和集沙效率受扰动问题,提出了分流对冲与多级扩容组合降速法,设计了分流对冲与多级扩容组合式自动集沙仪,阐述了风沙分离器和数据无线采集系统的设计原理,并对风沙分离器降速及分离性能、集沙仪抗强风干扰性能和集沙效率等进行了试验分析。结果表明,分流对冲与多级扩容组合式自动集沙仪具备了抗强风干扰性能,可实时、连续和远距离无线采集数据,自由旋转的起动风速为4.23 m/s,等动力性为92.94%,平均集沙效率为90.42%,当风速低于18 m/s时,粒径55.36μm以上的土样只要进入集沙仪,就可被完全收集;数据无线采集系统的供电续航能力达31 h以上,无障碍时信号传输距离为208.51 m,可较好地满足土壤风蚀量的自动观测需求。 相似文献
94.
《Veterinary anaesthesia and analgesia》2022,49(1):85-94
ObjectiveTo compare the efficacy of single-breath continuous positive airway pressure manoeuvre (CPAP-M) with inhaled salbutamol, and a combination of both.Study designRandomized, clinical study.AnimalsA total of 62 client-owned horses (American Society of Anesthesiologists status III–V) anaesthetized for laparotomy.MethodsHorses were premedicated with intravenous (IV) xylazine (0.4–0.6 mg kg–1), anaesthesia was induced with midazolam (0.06 mg kg–1 IV) and ketamine (2.2 mg kg–1 IV) and maintained with isoflurane in oxygen using volume-controlled ventilation without positive end-expiratory pressure. If PaO2 was < 100 mmHg (13.3 kPa), either a CPAP-M (50 cmH2O for 45 seconds) or salbutamol (0.002 mg kg–1) was administered. The intervention was considered successful if PaO2 reached 100 mmHg (13.3 kPa). If PaO2 remained < 100 mmHg (13.3 kPa), treatments were switched. PaO2/FiO2 ratio and estimated shunt fraction (F-shunt) were derived from data obtained from arterial blood gas measurements. Dynamic compliance (Cdyn) was calculated from variables recorded at the moment of arterial blood analysis. Fisher’s exact tests compared success rates between treatments, and linear models were performed to test whether the treatment modified the values of the measurements; p < 0.05.ResultsSalbutamol was the first intervention in 28 horses and was effective in 22 horses. CPAP-M was the first intervention in 34 horses and was effective in 26 horses. CPAP-M after salbutamol was performed in six horses, with four responders, and salbutamol after CPAP-M was administered to eight horses, with one responder. Salbutamol, but not CPAP-M, significantly decreased F-shunt. Both salbutamol and CPAP-M significantly increased Cdyn.Conclusions and clinical relevanceSalbutamol and CPAP-M were comparably effective in improving oxygenation and Cdyn in anaesthetized horses with PaO2 < 100 mmHg (13.3 kPa). Whether combining both treatments might be beneficial needs to be confirmed on a larger number of horses. 相似文献
95.
96.
Although nowadays there are many electric power measuring methods in china,some of them still have many power theft preventing bugs.To measure big and middle consumers' electric power consumption ,it is hard to prevent consumers from stealing power energy by the means of current which is difficult to be checked up by relevant products and preventing stealing power energy technology, because of using CTs to converting current.The authors especially use the example of the three phase three element active electric power meter, analyses other power theft methods and summarizes the new preventing stealing power energy technology. In accordance with the characteristic of the power measuring and on the basis of the analyzing the right method of resolving the problem,the three phase four wire system power theft preventing device can detect all sorts of stealing ,especially to the stealing by the means of current in time and accutately.This device has acquired good effect in the application of power system. 相似文献
97.
Cellophane banding for the gradual attenuation of single extrahepatic portosystemic shunts in eleven dogs 总被引:1,自引:0,他引:1
Objective To evaluate the efficacy and short term effects of a cellophane banding technique for progressive attenuation of canine single extrahepatic portosystemic shunts.
Design A prospective trial of 11 dogs with single congenital extrahepatic shunts.
Procedure Rectal ammonia tolerance testing and routine biochemical tests were performed preoperatively on all dogs. In seven dogs, preoperative abdominal Doppler ultrasonography was also performed. Exploratory laparotomy revealed a single extrahepatic portocaval shunt in each animal, which was attenuated using a cellophane band with an internal diameter of 2 to 3 mm. The abdomen was closed routinely. Follow-up biochemical analysis and abdominal Doppler ultrasonography or splenoportography were performed postoperatively.
Results The shunt was not amenable to total ligation in 11 dogs, based upon reported criteria. All dogs recovered uneventfully from surgery without evidence of portal hypertension, and showed clinical improvement thereafter. Shunt occlusion was deemed to have occurred in 10 dogs based on resolution of biochemical and/or sonographic abnormalities. One dog continued to have sonographic evidence of portosystemic shunting when evaluated 3 weeks after surgery, despite normal ammonia tolerance, but was lost to subsequent follow-up. Two dogs, in which 3 mm cellophane bands were placed, experienced delayed shunt occlusion.
Conclusion Cellophane banding is simple to perform, and causes progressive attenuation of single extrahepatic shunts in dogs. Further work is needed to determine the maximum diameter of a cellophane band which will produce total attenuation, and the long-term safety and reliability of the treatment. 相似文献
Design A prospective trial of 11 dogs with single congenital extrahepatic shunts.
Procedure Rectal ammonia tolerance testing and routine biochemical tests were performed preoperatively on all dogs. In seven dogs, preoperative abdominal Doppler ultrasonography was also performed. Exploratory laparotomy revealed a single extrahepatic portocaval shunt in each animal, which was attenuated using a cellophane band with an internal diameter of 2 to 3 mm. The abdomen was closed routinely. Follow-up biochemical analysis and abdominal Doppler ultrasonography or splenoportography were performed postoperatively.
Results The shunt was not amenable to total ligation in 11 dogs, based upon reported criteria. All dogs recovered uneventfully from surgery without evidence of portal hypertension, and showed clinical improvement thereafter. Shunt occlusion was deemed to have occurred in 10 dogs based on resolution of biochemical and/or sonographic abnormalities. One dog continued to have sonographic evidence of portosystemic shunting when evaluated 3 weeks after surgery, despite normal ammonia tolerance, but was lost to subsequent follow-up. Two dogs, in which 3 mm cellophane bands were placed, experienced delayed shunt occlusion.
Conclusion Cellophane banding is simple to perform, and causes progressive attenuation of single extrahepatic shunts in dogs. Further work is needed to determine the maximum diameter of a cellophane band which will produce total attenuation, and the long-term safety and reliability of the treatment. 相似文献
98.
99.
Federica Morandi Robert C. Cole Karen M. Tobias Clifford R. Berry James Avenell Gregory B. Daniel 《Veterinary radiology & ultrasound》2005,46(2):153-161
Ultrasound-guided percutaneous trans-splenic portal scintigraphy (TSPS) using 99mTcO4(-) has been used to image the portal venous system in normal dogs. Compared with per-rectal portal scintigraphy, it provides higher count density, consistent nuclear venograms of the splenic and portal vein, and significantly decreased radiation exposures. This paper describes the use of TSPS for the diagnosis of portosystemic shunts in 28 dogs. TSPS was performed injecting 70 +/- 28 MBq of 99mTcO4(-) (mean +/- SD) into the splenic parenchyma with ultrasound guidance. A dynamic acquisition at a frame rate of four frames/s for 5 min was initiated after placement of the needle and approximately 2s prior to injection. All dogs had diagnoses confirmed via exploratory laparotomy or ultrasonographic identification of the shunting vessel(s). Three studies (10.7%) were nondiagnostic because of intraperitoneal rather than intrasplenic injection of the radionuclide. Three pathways were recognized on the scintigraphic images: (1) portoazygos shunts--the 99mTcO4(-) bolus traveled dorsally, running parallel to the spine and entering the heart craniodorsally; (2) single portocaval or splenocaval shunts--the 99mTcO4(-) bolus ran from the area of the portal vein/splenic vein junction in a linear fashion toward the caudal vena cava entering the heart caudally; (3) internal thoracic shunt-the 99mTcO4 bolus traveled ventrally along the thorax and abdomen entering the cranial aspect of the heart. Single and multiple shunts were easily distinguished. There were no distinguishing features between single intra and extrahepatic portocaval shunts. 相似文献
100.
Rochelle M. Salwei DVM Robert T. O''Brien DVM MS Jodi S. Matheson DVM 《Veterinary radiology & ultrasound》2003,44(3):301-305
Contrast harmonic ultrasound was used to determine macrovascular and perfusion patterns in three dogs with congenital extrahepatic solitary portosystemic shunts (PSS). With coded harmonic angiographic ultrasound, the size and tortuosity of the hepatic arteries were subjectively increased. Single pulse intermittent low-amplitude harmonic perfusion imaging provided contrast enhancement time-intensity curves from regions of interest in the liver. Mean (+/- standard deviation) peak perfusion times of dogs with PSS were significantly shorter (p = 0.01; 7.0 +/- 2.0 s) than reported in normal dogs (22.8 +/- 6.8 s). The contrast inflow slope for the dogs with PSS (14.6 +/- 3.7 pixel intensity units [PIU] was significantly (p = 0.05) larger than reported for normal dogs (3.6 +/- 1.4 PIU/s). These results indicate that combined coded harmonic angiographic and contrast harmonic perfusion sonography can be used to detect increased hepatic arterial blood flow as an indicator of PSS in dogs. 相似文献