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31.
Rapid vasicular resistance adjustments in the brain and in the circle of Willis have been continuously measured and enhanced by signal averaging methods. Naftidrofuryl, a drug chemically similar to local anesthetics and to beta adrenergic blocking agents, increases local CBF by reducing resistance in brain and in extracerebral supply arteries. It has also been reported to affect brain metabolism. Other similar drugs merit study for potential effects on CBF and brain metabolism which may be useful in treatment.  相似文献   
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Seven calves seven to 30 days of age were given Mycoplasma bovis antigen by different routes. Immunization was in two phases. The first consisted of single or multiple SC, IV or oral doses of antigen for two to four weeks. The second phase consisted of multiple SC or ID injections given from the eighth to the 19th week. The experiment was terminated at 26 weeks. Antibody titers were followed by indirect hemagglutination, growth inhibition and tetrazolium reduction inhibition. Total serum protein, protein fractions and IgG and IgM concentrations were determined in serums of one calf and the distribution of indirect hemagglutination antibodies in IgG and IgM classes were determined in serums of two of the calves. Indirect hemagglutination titers of 1280 and peak titers of >20,480 occurred after the first and second phases respectively. There was no relationship between total serum IgG or IgM concentrations and indirect hemagglutination titers. In one calf given M. bovis antigen in one dose SC and five weekly doses IV in phase I, indirect hemagglutination antibodies appeared in IgM within one week and IgG by four weeks, IgG antibody activity rose steadily until the 17th week but declined at the 26th week, whereas IgM activity after the initial rise dropped at the 13th week but rose even higher as a result of second phase ID injections. Another calf given six weekly IV doses of M. bovis antigen in phase I developed indirect hemagglutination antibodies in IgM peaking at four weeks then declining but with no IgG response. Activity in both IgM and IgG occurred after the second phase. Growth inhibition antibodies were found only on two occasions in one calf serum and tetrazolium reduction inhibition activity when tested never gave titres exceeding 1:32.  相似文献   
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Progressive systemic sclerosis may be associated with focal myocardial fibrosis. Electrocardiographic abnormalities including conduction block are common in progressive systemic sclerosis but whether they are due to direct destruction of the specialized conduction tissue of the heart is uncertain. The conduction systems of 35 patients with progressive systemic sclerosis were studied. Of these 35 patients, 17 (50 per cent) had myocardial fibrosis of the type seen in progressive systemic sclerosis. In 10 of the 17, it was severe. Sinus node fibrosis was present in 13 patients and was nearly as frequent in those with as in those without the progressive systemic sclerosis myocardial lesion. Overlying pericarditis may have contributed to the fibrotic changes within the sinoatrial nodes in seven of the 13 patients. The atrioventricular node and main His bundles were normal. However, fibrotic changes were found in the proximal bundle systems in six patients. In three of the six, severe myocardial progressive systemic sclerosis was present, two had focal fibrous atrophy of the left bundle, and one had complete interruption of the right bundle. In only the latter patient was this reflected in the electrocardiogram which showed a right bundle branch block. Three patients without progressive systemic sclerosis myocardial lesions also had fibrous atrophy of a portion of the proximal left bundle branch, and in one the electrocardiogram showed an isolated left anterior hemiblock. Thus, morphologic abnormalities within the conduction system in our patients are difficult to attribute to progressive systemic sclerosis per se. Furthermore, although conduction abnormalities were more frequent in patients with myocardial disease, specific conduction system disease was not the cause in most patients. As has been noted in ischemic heart disease, the conduction system appears to be relatively spared from the myocardial changes of progressive systemic sclerosis, and the high incidence of conduction disturbances in this condition may be a consequence, rather, of damage to working myocardium.  相似文献   
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一种自适应的加权均值滤波器   总被引:1,自引:0,他引:1  
提出了一种基于灰度值相似度和空间临近度的自适应加权均值滤波器.滤波器充分利用处理的像素点的局部信息,以区分图像局部的变化是由于噪声引起的还是因图像特征的变化(如边缘等)所引起.经仿真试验表明,文中方法在噪声的去除和边缘保存上,与其他几种图像去噪的方法相比,更为简单有效,且易于硬件实现.  相似文献   
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