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31.
Background: Angiotensin converting enzyme inhibitors (ACEIs) are recommended in people to treat asymptomatic (occult) dilated cardiomyopathy (DCM). Efficacy of therapy in occult DCM in dogs is unknown.
Hypothesis: ACEIs, specifically benazepril hydrochloride (BH), will delay the onset of overt DCM in Doberman Pinschers.
Animals: Ninety-one Doberman Pinschers were studied, 57 dogs received BH, and 34 dogs no ACEI.
Methods: Retrospective study of the medical records of all Doberman Pinschers with occult DCM that received BH or no ACEI between April 1989 and February 2003. Two criteria of left ventricular enlargement were used for enrollment: one independent of body weight (BW) (C1) and the other indexed to BW (C2). Cox proportional hazards analyses were used to identify variables associated with the onset of overt DCM.
Results: On univariate analysis the median time to onset of overt DCM was significantly longer for the benazepril group (for C1: 425 days for BH, 95% confidence interval [CI] 264–625 days; 339 days for no ACEI, CI 172–453 days, P = .02; for C2: 454 days for BH, CI 264–628 days; 356 days for no ACEI, CI 181–547 days, P = .02). The hazard ratio (HR) (benazepril/no ACEI) was 0.57, CI 0.35–0.94, P = .03 for C1; HR = 0.56, CI 0.34–0.93, P = .02 for C2. On multivariate analysis, BH significantly delayed onset of overt DCM (HR [benazepril/no ACEI] = 0.45, CI 0.26–0.78, P < .01, for C1; HR = 0.36, CI 0.21–0.63, P < .01, for C2).
Conclusions: BH in particular and ACEIs in general might delay the progression of occult DCM. Prospective studies are warranted to test this theory.  相似文献   
32.
在辽西半干旱地区,以苗圃地播种获得的刺槐1年生幼苗为对象,研究了刺槐实生苗不同留苗密度对苗木质量的影响。结果表明:留苗密度在12万~20万株·hm-2范围内,产出的Ⅰ级苗木的数量最多,达到6万~9万株·hm-2,且Ⅰ和Ⅱ级苗占总留苗株数的百分率达90%以上;留苗密度12株·hm-2,Ⅰ和Ⅱ级苗占总留苗株数的百分率能够达90%以上,但产出的Ⅰ级苗木的数量减少;留苗密度20株·hm-2,Ⅰ和Ⅱ级苗占总留苗株数的百分率低于90%,且产出的Ⅰ级苗木的数量减少。  相似文献   
33.
农村留守老人存在的问题及对策   总被引:3,自引:0,他引:3  
农村留守老人存在诸多的生活问题,笔者分析了存在的问题,并提出了对策方法。  相似文献   
34.
Dynamic left ventricular outflow tract obstruction (DLVOTO) is a common condition in cats and humans. In this case report, a dog is described with DLVOTO secondary to severe intra-abdominal hemorrhage caused by a hemangiosarcoma. The dog was a 9-year-old, 35.7-kg, spayed female German Shepard dog that presented with a history of tachypnea and collapse. A Levine II/VI systolic murmur was present at the heart base. Abdominal ultrasonography revealed a splenic mass and a large amount of ascites. Echocardiography showed a reduced left ventricular diameter and an increased aortic velocity caused by systolic anterior motion (SAM) of the mitral valve apparatus. The heart murmur and the SAM were resolved after treatment including a splenectomy and a blood transfusion.  相似文献   
35.
我校化学实验室首次开放,76名志愿者报名参加了这次探索性实验。以敌百虫为例阐述了有机磷农药检测原理、操作步骤,记录了实验数据并对它们进行了处理,总结出有机磷农药使用的最高限量和使用标准。  相似文献   
36.
 对活塞销冲孔连皮在通用钻床上夹紧钻孔时的夹紧力、切削力进行初步分析计算,提出活塞销因钻削轴向力和扭矩的作用而产生滑移的原因,为合理设计专机选择可靠夹紧装置提供依据。  相似文献   
37.
The objective of this study was to document changes in echocardiographic variables of left ventricular size and function noninvasively during acute normovolemic anemia. This model was developed as a pilot study with the purpose of providing baseline information to investigate the pathophysiology, and more specifically the effect on the heart, of canine babesiosis-induced anemia. The study group comprised of 11 mature healthy Beagle dogs that weighed between 9 and 15 kg. Severe normovolemic anemia was induced over a 3-4-day period by serial bleeding while maintaining normovolemia by autotransfusing plasma and infusing crystalloids. The dogs were then allowed to recover. Preanemic (mean Hct 46.7%, standard deviation [SD] 2.4%) echocardiographic variables of left ventricular performance (Fractional shortening, ejection fraction, end-systolic and end-diastolic ventricular volumes, cardiac index, and heart rate) were compared with those in the severely (mean Hct 15.3%, SD 1.1%), moderately (Hct mean 24.7%, SD 1.5%), and mildly (mean Hct 33.5%, SD 2.5%) anemic states, and between the anemic states. With the exception of end diastolic volume, there was a statistically significant (P < 0.05) increase in all variables in the severely anemic state vs. the preanemic and the mild and moderate anemic states. In concordance with previous invasive models, a hyperdynamic state of the left ventricle develops in response to experimentally induced acute canine normovolemic anemia in the conscious dog. Echocardiography has promise as a noninvasive technique of evaluating the cardiac changes in dogs having canine babesiosis.  相似文献   
38.
This paper describes the electrocardiographic, echocardiographic (two-dimensional, M-mode, contrast and Doppler) and non-selective angiocardiographic features in a 3 year old female Beagle with dilated coronary sinus due to persistent left cranial vena cava. Negative P waves in leads III and aVR and a positive P wave in lead aVL were seen. Echocardiographically, a hipoechoic circular structure was seen between the left atrium and the pericardium in the area where the coronary sinus is located. A velocity pattern with two peaks was obtained, one systolic with velocity = 0.44 ± 0.05 m/sec and the other diastolic with velocity = 0.27 ± 0.01 m/sec. By M-mode echocardiography, at level of the aorta and the left atrium, a linear structure was identified between the left atrium and the pericardium; this structure was characterized by phasic movements of the anterior wall during the cardiac cycle. Following a left cephalic vein injection of saline, bubbles were seen within the coronary sinus; when saline was injected into the right cephalic vein, bubbles were also seen within the coronary sinus and right atrium and ventricle. Non-selective angiocardiography confirmed a dilated coronary sinus with persistent left cranial vena cava. The right cranial vena cava was absent. The dog was clinically normal and the unusual vessel was an incidental finding.  相似文献   
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