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991.
基于统计参数图的脑功能磁共振成像数据处理方法 总被引:1,自引:0,他引:1
介绍了基于统计参数图的脑功能磁共振成像数据处理方法。脑功能磁共振成像由于其高的时间、空间分辨率、无创性等特点而得到广泛的应用。使用统计参数图进行脑功能成像的数据处理过程主要分为:原始数据的读取、图像预处理、统计分析和统计推论。图像预处理包括运动伪影的消除、图像标准化、图像空间平滑;统计分析包括广义线性模型的建立;统计推论包括T检验等。重点介绍了各个过程所使用的传统的处理方法和最新的处理方法。 相似文献
992.
S. A. Pavlishchuk 《Bulletin of experimental biology and medicine》1979,88(6):1413-1416
The adhesive-aggregative activity of the platelets and the rate of blood clotting were compared in 125 healthy subjects during an emergency adaptation reaction (emotional stress, ACTH loading) and in 157 patients with heart and circulatory diseases during the period of crisis, and also during acute drug therapy. Changes in the platelets and plasma-coagulative components of hemostasis were found to be opposite in direction, and on this basis new ideas were put forward to explain the hemostatic function of the platelets.Department of Internal Medicine, Kuban Red Army Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR N. A. Fedorov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 88, No. 12, pp. 669–672, December, 1979. 相似文献
993.
R. H. Ming D. Atluru C. W. Spellman T. Imir J. S. Goodwin R. G. Strickland 《Journal of clinical immunology》1987,7(1):59-63
The interleukin-2 pathway is essential for the normal immune response to antigen stimulation; we have examined the possibility that this may underlie abnormal peripheral blood lymphocyte immunoregulatory function that has been observed in patients with inflammatory bowel disease. We studied 11 patients with Crohn's disease and 5 with ulcerative colitis, all with quiescent disease activity. Peripheral blood mononuclear cells were isolated from these patients and from healthy age- and sex-matched controls. Interleukin-2 production after mitogen and phorbol-myristate acetate stimulation was similar in both groups: 381±71 (mean ± SE) U/ml by control cells and 451±70 by patient cells. Interleukin-2 receptor generation was also measured pre- and poststimulation by labeling with anti-Tac antibody. This was 10.45±1 and 69.95±3.85% for control cells and 11.41±1.38 and 60.9±4.25% for patients cells. Finally, we examined the response of these cells to interleukin-2 stimulation by generating cells with direct cytotoxicity to51Cr-labeled Daudi-cell targets. Control cells caused 59.5±46%51Cr release, whereas patient cells caused 50.8±5.18% release. None of the above results achieved statistical significance. We conclude that the peripheral blood interleukin-2 pathway is normal in inactive inflammatory bowel disease. 相似文献
994.
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997.
Summary Lymphocyte capping with concanavalin A was studied in 11 patients with hereditary cerebral haemorrhage with amyloidosis (Dutch type) and 10 controls. No difference in capping was found between patients and controls. Abnormal lymphocyte concanavalin A capping has been reported in patients with the Icelandic type of cerebral amyloidosis and in patients with Alzheimer's disease, a disease in which cerebral amyloid angiopathy can also be found. The results suggest a difference in pathogenesis between the Dutch type of cerebral amyloidosis and the other amyloid diseases.Members of the Amyloid Research Group, Leiden 相似文献
998.
M. Morinaga K. Hara M. Kageura Y. Hieda M. Takamoto S. Kashimura 《International journal of legal medicine》1990,103(8):567-572
Summary A screening method for detecting volatile hydrocarbons in blood has been developed using gas chromatography/mass spectrometry with a wide-bore capillary column and a headspace method. Toluene-d8 and indan were used as the internal standards for quantitative analysis. Hydrocarbons with retention indices from 600 to 1200 were simultaneously and quantitatively detected in relatively low concentrations (0.01 g/m1) in reconstructed ion chromatography. This method could prove useful in forensic cases in which urgent examination of complex hydrocarbon mixtures, e.g. petroleum components, is required.
Offprint requests to: K. Hara 相似文献
999.
M. Heilig L. Vècséi C. Wahlestedt Ch. Ailing E. Widerlöv 《Journal of neural transmission (Vienna, Austria : 1996)》1990,79(3):193-208
Summary The effects of centrally administered NPY on the brain monoamine systems were investigated in the rat. Neuropeptide Y (0.2–5.0 nmol), its C-terminal 13–36 amino acid (a.a.) fragment, NPY13–36 (0.4–10.0 nmol), or saline were injected into the right lateral cerebral ventricle of unrestrained rats. After l h the animals were decapitated, and the brains were taken out. Two cortical regions (frontal and parietal), the striatum, the hypothalamus, and the brain stem were dissected out. The tissue contents of noradrenaline (NA), dopamine (DA) and serotonin (5-HT), as well as of their major metabolites, 3-methoxy-4-hydroxy-phenylethylené glycol (MHPG), 3,4-dihydroxyphenylacetic acid (DOPAC) and 5-hydroxy-indole acetic acid (5-HIAA) were measured. The most consistent finding was a dose-related increase of both DA and DOPAC levels after treatment with NPY. This effect was reproduced by NPY13–36 in cortical tissue, whereas, in the sub-cortical regions, NPY13–36 only reproduced the effects of NPY on the DOPAC levels. Less consistent effects were found on the NA systems, in which NA levels showed a tendency to increase following low, and decrease after high doses of NPY. These effects were largely reproduced by NPY13–36. In addition, NPY increased tissue levels of MHPG in frontal cortical tissue in a dose-related manner. The brain 5-HT systems were not affected. 相似文献
1000.
M. Hohenegger M. Vermes W. Mauritz G. Redl P. Sporn P. Eiselsberg 《European archives of psychiatry and clinical neuroscience》1990,239(4):267-269
Summary Hydromineral metabolism and serum arginine-vasopressin (AVP) levels were investigated in 11 patients who sustained brain death. They showed various degrees of polyuria with low osmolality and low fractional sodium excretion. Urine osmolality was always below that of serum, and AVP levels were between 1.3 and 50.0 pg/ml vs 0.7–8.0 pg/ml in ten normal subjects. Thus central diabetes insipidus was excluded. A renal mechanism inducing water diuresis has to be assumed. The type of renal lesion, however, remains unclear.This work was supported by the Fonds zur Förderung der wissenschaftlichen Forschung, project no. 3100, Vienna 相似文献