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991.
振动减肥中腹壁脂肪的超声检测与力学特征 总被引:2,自引:0,他引:2
本文是在研究振动对生物体内物质的耗散作用的基础上,试图利用振动对动物腹壁脂肪进行减脂的探索。通过实验,证实了利用趋声作为手段,可以对动物体内的腹壁脂肪作无创伤活体测量,其误差仅在10%左右。使用振动对脂肪块得出了疲劳曲线和振动在生物体内传播的衰减曲线。对新鲜离体脂肪块所作振动模拟实验,证明在所使用的频率和振幅的振动作用下,能够迅速使脂肪的厚度消减,根据初步观察,在振动过程中有甘油从脂肪块中溢出,其消减体积的百分之八十为甘油成份,可以认为振动能促使脂肪细胞膜破裂或促使脂肪细胞内的脂滴水解,因此振动有可能成为减肥治疗方案中的一个重要措施。 相似文献
992.
Ho Chang Kuo Chih Lu Wang Chi Di Liang Hong Ren Yu Hsin Hsu Chen Lin Wang Kuender D Yang 《Journal of microbiology, immunology, and infection》2007,40(5):395-400
BACKGROUND AND PURPOSE: This study was conducted to investigate whether changes in the complete blood count (CBC)/differential count (DC) and C-reactive protein (CRP) were correlated to Kawasaki disease (KD) with coronary artery lesions (CALs). METHODS: A retrospective analysis was performed of all children with KD at Chang Gung Memorial Hospital at Kaohsiung from 2001 to 2006. KD patients were divided into those with and without CALs for testing of correlations with changes in CBC/DC and CRP levels. RESULTS: A total of 147 patients were enrolled for this analysis. Serial CBC/DC and CRP measurements and echocardiographic data for determination of CAL formation were obtained before and after intravenous immunoglobulin (IVIG) treatment. There were 44 (29%) KD patients having CAL formation (>3 mm in diameter of internal lumen). There was no significant difference in terms of age distribution and major diagnostic criteria between KD patients with and without CALs. Male KD patients, however, had a significantly higher rate of CAL formation (p=0.009). In multivariate logistical regression analysis, persistent monocytosis after IVIG treatment was the only factor significantly correlated to CAL formation (p=0.003). CONCLUSIONS: Of the febrile routine measurements of CBC/DC and CRP in KD, persistent monocytosis after IVIG treatment was correlated to CAL formation. Further studies to clarify the mechanism of monocytosis may help prevent the CALs of KD. 相似文献
993.
复杂手术常需多科医生协商制定综合性治疗方案,网络协同三维可视化软件可使方案制定直观而精确。我们采用VTK工具包对DICOM格式CT图像数据进行三维重建并作网格简化,将结果所得多边形网格模型无缝集成到用HOOPS/3DAF所开发的图形系统进行显示,并用HOOPS/Stream工具包转成适合网络传输的HSF无损压缩流文件,再用HOOPS/NET工具包实现基于Client/Server架构的协同三维交互可视化系统。所得三维重建结果清晰,协同三维可视化操作实时度高。本研究实现了一个协同手术仿真开发平台,该架构易于进一步添加模拟手术操作与修复体设计功能。 相似文献
994.
A. L. Dranov A. S. Dudnichenko I. A. Mezin R. F. Menzeleev Yu. M. Krasnopol'skii V. I. Shvets 《Bulletin of experimental biology and medicine》1996,121(1):77-80
Study of the toxicity and pharmacokinetics of free and liposomal forms of cytostatics revealed an appreciable decrease of
the toxicity of high drug doses and prolongation of drug action in liposomes. The distribution of drugs in organs and tissues
is shown.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N
o
1, pp. 85–88, January, 1996 相似文献
995.
N. N. Dygalo G. T. Shishkina N. Yu. Surnina A. A. Yushkova 《Bulletin of experimental biology and medicine》1995,119(3):320-322
Tissue specificity of the effect of glucocorticoids on the density of β-adrenoreceptors is shown. The hormone increases the
number of receptors in the lungs, but has no effect on their density in the cerebral cortex either in the norm or after down-regulation.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N
o
3, pp. 328–330, March, 1995
Presented by V. A. Trufakin, Member of the Russian Academy of Medical Sciences 相似文献
996.
In a previous study we demonstrated thirteen amino acids to be essential and two to be partially essential for lymphocyte proliferation. Arginine is one of the essential amino acids, and the highly purified arginase strongly inhibited lymphocyte proliferation. The modulation of lymphocyte growth by various amino acid-degrading enzymes was studied. Peripheral lymphocytes were cultured in RPMI 1640 with or without amino acid-degrading enzyme for 72 h. A total of 17 commercial L-amino acid-degrading enzymes were studied. At 10 micrograms/ml, both lysine decarboxylase and asparaginase completely inhibited lymphocyte proliferation, arginase resulted in 78% inhibition and tyrosinase 57% inhibition. Other enzymes inhibited less than 20% lymphocyte proliferation; they included alanine dehydrogenase, arginine decarboxylase, aspartase, glutamic decarboxylase, glutamic dehydrogenase, glutaminase, histidase, histidine decarboxylase, leucine dehydrogenase, phenylalanine decarboxylase, phenylalanine hydroxylase, tryptophanase, and tyrosine decarboxylase. All four enzymes that strongly inhibited lymphocyte proliferation degraded amino acids that are essential for lymphocyte growth. 相似文献
997.
The application of x-ray flat panel imagers (FPIs) in cone beam volume CT (CBVCT) has attracted increasing attention. However, due to a deficient semiconductor array manufacturing process, defective cells unavoidably exist in x-ray FPIs. These defective cells cause their corresponding image pixels in a projection image to behave abnormally in signal gray level, and result in severe streak and ring artifacts in a CBVCT image reconstructed from the projection images. Since a three-dimensional (3-D) back-projection is involved in CBVCT, the formation of the streak and ring artifacts is different from that in the two-dimensional (2-D) fan beam CT. In this paper, a geometric analysis of the abnormality propagation in the 3D back-projection is presented, and the morphology of the streak and ring artifacts caused by the abnormality propagation is investigated through both computer simulation and phantom studies. In order to calibrate those artifacts, a 2D wavelet-analysis-based statistical approach to correct the abnormal pixels is proposed. The approach consists of three steps: (1) the location-invariant defective cells in an x-ray FPI are recognized by applying 2-D wavelet analysis on flat-field images, and a comprehensive defective cell template is acquired; (2) based upon the template, the abnormal signal gray level of the projection image pixels corresponding to the location-invariant defective cells is replaced with the interpolation of that of their normal neighbor pixels; (3) that corresponding to the isolated location-variant defective cells are corrected using a narrow-windowed median filter. The CBVCT images of a CT low-contrast phantom are employed to evaluate this proposed approach, showing that the streak and ring artifacts can be reliably eliminated. The novelty and merit of the approach are the incorporation of the wavelet analysis whose intrinsic multi-resolution analysis and localizability make the recognition algorithm robust under variable x-ray exposure levels between 30% and 70% of the dynamic range of an x-ray FPI. 相似文献
998.
A Bertelli A Conte G Ronca D Segnini G Yu 《International journal of tissue reactions》1991,13(1):41-43
Endothelial cells may be damaged by oxygen reactive species produced by granulocytes, by transition metal ions or by xanthine oxidase, an enzyme present in great quantity in these cells. Since it has been observed that propionyl carnitine protects the heart from peroxidation, we have investigated the effect of this compound on the formation of thiobarbituric acid reactive oxidation products (TBAR) in endothelial membranes. The peroxidation systems used were a mixture of Fe3+ and Fe2+, hydrogen peroxide and Fe2+, or xanthine oxidase-- xanthine. Propionyl carnitine at millimolar concentrations decreases TBAR formation. The protection is concentration-dependent and is almost absent in the presence of propionate and carnitine. From these results it appears that propionyl carnitine may protect not only myocardium but also vessels from peroxidative damage that occurs during ischaemia and reperfusion. 相似文献
999.
Young rats with lesions to either the globus pallidus, substantia nigra, median raphe, or pontine reticular formation have previously been reported to be deficient in learning a wide variety of laboratory tasks. In the current study, weanling rats subjected to one of these lesions were rested for three weeks, then examined for acquisition and extinction of a water-motivated straight alley task, and finally tested on luminous flux discriminations of increasing difficulty. All brain-damaged groups were slower than the controls in extinguishing the alley task and only the median raphe group failed to show an impairment on the discrimination problems. These results and others suggest that the foregoing lesions produce deficits in inhibitory and attentional processes. The possibility is discussed that young rats bearing these lesions might serve as a model for the investigation of the neurobiological and cognitive disturbances underlying certain classes of mental retardation in children. 相似文献
1000.
Chae BW Chung JP Park YN Yoon DS Yu JS Lee SJ Lee KS Chung JB Lee SI Moon YM Kang JK 《Yonsei medical journal》1999,40(1):84-89
Villous adenomas are benign epithelial lesions with malignant potential which can occur at any site in the gastrointestinal tract. They are usually encountered in the rectum and colon, less frequently in the small bowel and very rarely in the biliary trees. Nine cases of bile duct villous adenomas have been reported in the literature. However, 4 cases of bile duct villous adenomas have been reported in the Korean literature. Recently, we experienced a case of villous adenoma in the common hepatic duct in a 77-year-old man presenting with obstructive jaundice in which preoperative histologic diagnosis of villous adenoma played a critical role in managing this patient. Herein, we present a case report of bile duct villous adenoma and a review of the reported cases in Korea to help define and manage this rare disease entity in the bile ducts. In addition, confusing nomenclature of bile duct adenomas is discussed. 相似文献