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41.
Prevalence and Prognostic Importance of Pulmonary Hypertension in Dogs with Myxomatous Mitral Valve Disease
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M. Borgarelli J. Abbott L. Braz‐Ruivo D. Chiavegato S. Crosara K. Lamb I. Ljungvall M. Poggi R.A. Santilli J. Haggstrom 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2015,29(2):569-574
Background
Pulmonary hypertension (PH) is common in dogs with myxomatous mitral valve disease (MMVD) but its effect on clinical outcome has not been investigated.Hypothesis/objectives
The presence of PH worsens the outcome in dogs with MMVD. To compare survival times of dogs with MMVD and PH to those without PH.Animals
Two hundred and twelve client‐owned dogs.Methods
Case review study. Medical records of dogs diagnosed with ACVIM stage B2 and C MMVD between January 2010 and December 2011 were retrospectively reviewed. Long‐term outcome was determined by telephone interview or from the medical record. End of the observation period was March 2013. PH was identified if tricuspid regurgitation peak velocity was >3 m/s.Results
Two hundred and twelve were identified. Eighty‐three dogs (39%) had PH. PH was more commonly identified in stage C compared to B2 (P < .0001). One hundred and five (49.5%) dogs died during the observation period. Median survival time for the entire study population was 567 days (95% CI 512–743). Stage C (P = .003), the presence of PH (P = .009), left atrial to aortic root ratio (LA/Ao) >1.7 (P = .0002), normalized left‐ventricular end‐diastolic diameter (LVEDn) >1.73 (P = .048), and tricuspid regurgitation pressure gradient (TRPG) >55 mmHg (P = .009) were associated with worse outcomes in the univariate analyses. The presence of TRPG >55 mmHg (HR 1.8 95% CI 1–2.9; P = .05) and LA/Ao > 1.7 (HR 2 95% CI 1.2–3.4; P = .01) remained significant predictors of worse outcome in the multivariate analysis.Conclusions and Clinical Importance
In dogs with MMVD, moderate to severe PH worsens outcome. 相似文献42.
43.
本文利用常规高空资料、地面实况资料和雷达资料,从天气形势、物理量场和雷达回波变化特征等方面对2020年5月23日发生在龙口市的一次冰雹天气过程进行了分析。结果表明:此次降雹过程主要是在冷涡横槽和地面气旋的共同影响下发生的;充足的水汽条件,上干冷下暖湿的不稳定层结条件以及低层辐合、高层辐散动力条件是强对流天气产生的基础。可充分利用冰雹天气在雷达反射率和VIL图上的明显特征来做临近的预报预警服务。 相似文献
44.
45.
Two non-invasive blood pressure (NIBP) devices (oscillometry and Doppler) were compared to invasive blood pressure using a Bland–Altman analysis, in anesthetized and conscious dogs. When considering the systolic arterial pressure only during general anesthesia, both NIBP devices slightly underestimated the systolic arterial blood pressure however the precision and the limits of agreement for the Doppler were of a greater magnitude. This indicates a worse clinical performance by the Doppler. The performance of both NIBP devices deteriorated as measured in conscious animals. In general, for the oscillometric device, determination of invasive diastolic and mean arterial pressures was better than the invasive systolic arterial pressure. Overall, the oscillometric device satisfied more of the criteria set by the American College of Veterinary Internal Medicine consensus statement. Based upon these results, the oscillometric device is more reliable than the Doppler in the determination of blood pressure in healthy medium to large breed dogs. 相似文献
46.
Jason E. Anton Kristine L. Vernon Dale E. Kelley John R. Gibbons Glen Birrenkott Chris J. Mortensen 《Journal of Equine Veterinary Science》2014
Our previous research has demonstrated moderate exercise can be detrimental to early pregnancy in the mare, but little work has examined exercise after pregnancy has been detected. We exercised mares (n = 8) 6 days a week for 45 min from Day 16 until Day 80 of gestation. Color Doppler ultrasonography was used to evaluate embryonic vesicle size, fetal length, and uterine blood flow. Blood was sampled every other day to analyze cortisol and progesterone concentrations. Results indicated that exercising pregnant mares (n = 4) led to greater (P < .01) cortisol concentrations 30 min after the exercise period. No overall treatment effect could be detected in progesterone concentrations; however, following Day 60 of gestation, progesterone concentrations were lower (P < .05) in exercised mares. Additionally, progesterone concentrations peaked earlier in exercised mares at Day 52 of gestation compared to peak levels at Day 68 of gestation for control mares. No significant effects were detected in embryonic vesicle size. Fetal length tended (P = .06) to be longer in the conceptus of exercised mares. Uterine blood flow did not differ between groups but increased as pregnancy progressed (P < .001) in both groups. All mares in this study went on to deliver healthy foals and suffered no difficulties during parturition. These results indicated that moderate exercise was not detrimental to mare pregnancy. 相似文献
47.
Cardiac effects of the β2-adrenergic agent clenbuterol have been the focus of many studies, but effects on myocardial velocities and myocardial deformation parameters have not yet been evaluated in horses affected with recurrent airway obstruction (RAO) using tissue Doppler imaging (TDI) and two-dimensional speckle tracking (2DST). In our study, 7 horses affected by RAO were treated over 14 days with clenbuterol, 0.8 μg/kg every 12 hours. Standard echocardiographic, TDI (pulsed wave and color TDI), and 2DST examinations were performed before and after the treatment period. Myocardial function was recorded in the right parasternal short-axis view. Percent of fractional shortening and two-dimensional echocardiography (2DE) measurements did not show any significant changes after 2 weeks of treatment. Early diastolic velocity, E, increased significantly after clenbuterol in the left ventricular free wall (LVFW; P = .001). The E/late diastolic velocity (A) quotient (P = .003) and the isovolumetric contractility (P = .035) also increased significantly after treatment. Time parameters, particularly the time interval between the Q-wave in the echocardiograph and atrial release, the time of diastole and Tei index (parameter of global ventricular function), decreased significantly after clenbuterol administration in the LVFW (P = .014/P = .028/P = .015, respectively). The 2DE speckle tracking revealed a significant increase of the early diastolic systolic strain rate (P = .01) in the LVFW after therapy. In conclusion, 2 weeks of treatment with clenbuterol at a dosage of 0.8 μg/kg every 12 hours led to improved cardiac function in severely RAO-affected horses. This could be a sign of myocardial restoration (re-remodeling) after therapy. 相似文献
48.
为探讨星载激光雷达数据ICESat-2(Ice,Cloud,and land Elevation Satellite-2)在山地森林地上生物量(Aboveground Biomass,AGB)的估测可行性和方法。以ATLAS(Advanced Terrain Laser Altimeter System)光子点云数据为主要信息源,以滇西北典型山地香格里拉为研究区,结合地面54块实测生物量遥感样地,在前期进行点云数据去噪、分类预处理基础上,对研究区74 873个林地光斑进行冠层参数及地形因子的提取(共计53个变量),采用非参数模型随机森林回归和超参数优化后的随机森林进行建模,以均方根误差(Root Mean Square Error,RMSE)、决定系数(R2)、总体估测精度(P1)作为模型的评价指标,建立研究区AGB模型。研究结果表明:1)分析以ICESat-2/ATLAS提取的冠层参数、地形因子与生物量的相关性可知,冠层光子总数与生物量具有极显著相关性(P<0.01),基于陆地卫星的乔木冠层百分比、冠层光子比率、坡度、光子总数、表观反射率与生物量具有显著相关性(0.01
相似文献
49.
Jordan Q. Jaeger DVM MS John S. Mattoon DVM Shane W. Bateman DVM DVSc Federica Morandi DVM MS 《Veterinary radiology & ultrasound》2003,44(1):72-79
The imaging findings in two miniature schnauzers with acute necrotizing pancreatitis are described. Both dogs were treated previously for diabetes mellitus and hyperlipidemia. Vomiting, anorexia, and lethargy were observed in both dogs at presentation. Laboratory evaluations supportive of pancreatitis included left shift, abnormally high serum amylase and lipase activities, hypocalcemia, and abnormally high serum activities of liver enzymes. Sonographically, both dogs had diffusely enlarged hypoechoic pancreatic tissue with anechoic foci compatible with necrosis, abscessation, phlegmon, and pseudocysts formation. Contrast-enhanced computed tomography (CT) findings in both dogs were compatible with pancreatic necrosis. Dog 1 was managed medically for 11 days. Follow-up CT scan in this dog disclosed decreased pancreatic size and increased contrast enhancement compatible with partial resolution of pancreatitis. 相似文献
50.
Sabine Riesen DR MED VET Valerie Schmid DR MED VET Lorrie Gaschen DVM DR MED VET Andre Busato DR MED VET MSC Johann Lang PD DR MED VET 《Veterinary radiology & ultrasound》2002,43(6):554-560
The purpose of this study was to measure splanchnic blood flow during digestion in unsedated dogs by using duplex Doppler sonography. The study population consisted of 12 healthy dogs. Blood flow in the cranial mesenteric artery, the celiac artery, and the aorta was measured before a test meal and at 20, 60, and 90 minutes after eating. The following measurements were made or calculated: vessel diameter, peak systolic velocity, end diastolic velocity, mean velocity, resistive index, pulsatility index, and flow volume. There was a significant postprandial decrease in the resistive and pulsatility indices in both the cranial mesenteric (preprandial RI = 0.867, postprandial RI = 0.796, preprandial PI = 3.033, postprandial PI = 2.173) and the celiac (preprandial RI = 0.854, postprandial RI = 0.769, preprandial PI = 2.639, postprandial PI = 1.930) arteries. In both vessels the end diastolic velocity, the mean velocity, and the flow volume increased significantly postprandially. These changes occurred significantly earlier in the celiac artery than in the cranial mesenteric artery. The findings most likely correspond to postprandial splanchnic vasodilation. Doppler ultrasound provide a good methode of detecting changes in postprandial splanchnic blood flow in the dog. 相似文献