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81.
目的:通过对上矢状窦(SSS)旁大脑桥静脉的显微解剖、影像学观察及其对照研究,为各种纵裂间手术入路中桥静脉的保护提供基础。方法:分别对30例(60侧)上矢状窦和颈内静脉内灌注蓝色乳胶的成人头颅湿标本、40侧DSA静脉相和16侧CTV进行显微解剖和影像学观察。结果:上矢状窦前部和后部分别有一缺乏桥静脉注入段,显微解剖、DSA和CTV观察上矢状窦旁桥静脉的数量分别为11.2支、8.9支和7.0支,DSA和CTV观察发现桥静脉注入上矢状窦处常显示不清。结论:熟悉和比较上矢状窦旁桥静脉的解剖学和影像学特征有利于各种纵裂间手术入路和手术过程中桥静脉的保护。 相似文献
82.
因为数字化学习环境是未来图书馆事业的发展趋势,文章从图书馆数字化学习环境的内涵开始,分析了医院图书馆数字化学习环境建设的必要性及其现实的可行性,提出了图书馆软件环境和硬件环境的建设及两者的有机结合是医院图书馆数字化学习环境建设的重要保障。 相似文献
83.
A case of infantile digital fibromatosis was studied by light and electron microscopic histochemistry. Using two different acidic solutions of phosphotungstic acid at varying pHs, the round inclusions characteristic of this tumor were shown to have a high protein content with little or no carbohydrate. The histochemical reactivity of the inclusions was similar to that of the cytoplasmic microfibrils in the tumors cells and consistent with the idea that both the inclusions and the microfibrils represent actin. There is, however, no definite proof that the tumor cells are myofibroblasts. At the present time, this tumor should be viewed as a peculiar expression of deranged assembly or metabolism of filamentous proteins or both. 相似文献
84.
A. N. Chalazonitis MD Ph.D D. Koumarianos RT J. Tzovara MD P. Chronopoulos MD 《Journal of digital imaging》2003,16(2):216-229
Over the past decade, the technology that permits images to be digitized and the reduction in the cost of digital equipment allows quick digital transfer of any conventional radiological film. Images then can be transferred to a personal computer, and several software programs are available that can manipulate their digital appearance. In this article, the fundamentals of digital imaging are discussed, as well as the wide variety of optional adjustments that the Adobe Photoshop 6.0 (Adobe Systems, San Jose, CA) program can offer to present radiological images with satisfactory digital imaging quality. 相似文献
85.
Mouse monoclonal antibodies to the human C3b receptor 总被引:7,自引:0,他引:7
J Cook E Fischer C Boucheix M Mirsrahi M H Jouvin L Weiss R M Jack M D Kazatchkine 《Molecular immunology》1985,22(5):531-539
Mouse monoclonal antibodies were raised against the human C3b receptor (CR1) molecule that had been purified from solubilized erythrocytes membranes. Four hybridomas were selected, cloned and expanded because their supernatants reacted strongly with insolubilized CR1 by ELISA and intensely stained B-dependent areas of the spleen and glomerular podocytes by indirect immunofluorescence. The four monoclonal antibodies, named J3D3, J8B10, J3B11 and J7C2, were IgG1 immunoglobulins. J3D3 immunoprecipitated two protein bands of apparent mol. wts 200,000 and 220,000 from 125I-surface-labeled human erythrocytes, which correspond to the two major allotypic forms of CR1. By indirect immunofluorescence, monoclonal antibodies stained polymorphonuclear leucocytes (PMN), most peripheral blood B-cells and a small subset of peripheral blood T-cells. J3D3 bound to CR1 on erythrocytes, PMN and lymphocytes with an affinity of 1-3 X 10(9) M-1 and recognized 170-1330 antigenic CR1 sites with an average of 740 sites/erythrocyte in 100 healthy individuals, approx. 50,000 sites/PMN and 15,000 sites/lymphocyte. There was a bimodal distribution of CR1 numbers on erythrocyte in the normal population. The four monoclonal antibodies similarly inhibited CR1-mediated decay of preformed cell-bound alternative- and classical-pathway C3 convertase sites. Two antibodies, J3D3 and J3B11, inhibited C3b-dependent rosette formation with lymphocytes, although much less efficiently than F(ab')2 polyclonal anti-CR1 antibody. Differences that were observed in the relative capacity of the antibodies to inhibit some of the functions of CR1 and in their ability to compete for binding of 125I-J3D3 to CR1 on erythrocytes, suggested that they are directed against different epitopes on CR1. Monoclonal antibodies provide useful means to assess and analyze the biological and immunoregulatory functions of the C3b receptor. 相似文献
86.
WOLFRAM GRIMM JÜRGEN HOFFMANN ULRICH KÖHLER JÖRG HEITMANN JÖRG H. PETER PETER VON WICHERT BERNHARD MAISCH 《Journal of sleep research》1995,4(S1):160-165
SUMMARY Twelve patients (aged 48 ± 12 y) with ventricular asystole of >3s due to complete atrioventricular (AV) block ( n = 8), sinoatrial (SA) block or sinus node arrest ( n = 3) or both ( n = 1) associated with obstructive sleep apnoea underwent invasive electrophysiological evaluation of sinus node function and AV conduction properties before and after administration of atropine (0.02 mg kg-1 ). Ventricular asystole lasted for 5.9 ± 2.8 s (range 3.1–13 s). Sinus node function was assessed by measurement of sinus node recovery time, sinoatrial conduction time, and the response of sinus rate to atropine. Parameters of AV-conduction assessment included AH- and HV-intervals, AV- and VA-Wenckebach periods, and effective refractory period of the AV node before and after atropine. Sinus node function was normal in 11 of the 12 study patients and moderately abnormal in 1 patient. AV-nodal function was normal in 8 patients and moderately abnormal in 4 patients. A slightly prolonged HV-interval (59–63 ms) was present in 6 patients. Intra- or infra His block was not observed in any patient. In conclusion, normal or only moderately abnormal electrophysiological findings in patients with sleep apnoea-associated ventricular asystole suggest that a neurally mediated cardioinhibitory reflex may cause ventricular asystole in these patients. This sleep apnoea-triggered 'vasovagal' reflex may unmask pre-existing mild to moderate structural abnormalities of the AV conduction system. 相似文献
87.
目的:建立旋髂深动脉及穿支的数字化可视模型,为临床上旋髂深动脉穿支骨皮瓣的设计与安全截取提供形态学基础。方法:2具新鲜男尸,分别采用羧甲基纤维素/氧化铅水凝胶及明胶/氧化铅行一次性全身动脉造影,并进行连续螺旋CT扫描,运用Mimics软件,在计算机上对腰区相关重要结构进行计算机三维重建和立体显示。结果:该数字化可视模型能够清晰显示髋骨、髂外动脉、旋髂深动脉及其供血皮瓣的形态、位置及毗邻关系,并可任意方向的旋转观察。结论:重建的三维模型可以提供正常腰区皮瓣的三维动态解剖,为临床术前皮瓣设计提供了直观的数字化解剖依据。 相似文献
88.
序列解剖层片的全局和局部色彩校正 总被引:1,自引:0,他引:1
本研究提出了一种全局和局部相结合的序列解剖层片的色彩校正算法。利用数字人层片(中国女婴一号)上提供的彩色灰度卡对相邻层片间各颜色通道的色彩差异进行全局校正,以消除解剖数据集沿垂直方向的光照变化;再利用线性校正模型和差值图像各通道(R、G、B)的灰度局部直方图,对解剖数据集进行局部色彩差异校正。重建结果表明,经过全局和局部色彩校正后,重建视图中的明暗条纹基本消失,说明层片间颜色的不连续现象得到了校正。 相似文献
89.
This work describes our experience in reviewing the performance criteria for display systems and how we have implemented a
practical approach to the assessment of the workstation environment in a large tertiary care hospital. The acceptance criteria
contained in the draft report of Topic Group 18 of the American Association of Physicists in Medicine (AAPM) were used as
a basis for assessment of primary and secondary displays. A telescopic photometer was used to measure the maximum luminance
and the contrast ratio of the image for the displays used in our radiology department and in the operating and emergency rooms
using the standard Society of Motion Picture and Television Engineers (SMPTE) pattern, in ambient light and with light decreased
as much as possible. About half of the displays met the AAPM criteria for minimum luminance and contrast ratio in low light.
None of the systems met the contrast ratio criteria in ambient light. The challenges in improving the performance and calibrating
displays are discussed. 相似文献
90.
c AMP反应成分结合蛋白 (c AMP response elem ent-binding protein,CREB)是一种转录因子 ,它在磷酸化之后可调节靶基因的转录。 CREB在 13 3位置的丝氨酸的磷酸化 ,与脊髓中伤害性传入的处理有关 ,本文作者等用特殊抗体对此进行了免疫细胞化学研究。在正常大鼠 ,虽然几乎所有脊髓神经元的核中都可见 CREB的轻度着色 ,但磷酸化的 CREB仅见于双侧腰段脊髓的 ~ 层 (75± 15 vs60± 18)和 层 (9± 3 )。用福尔马林注射引起一侧后脚掌出现炎症时 ,可在双侧腰段脊髓看到磷酸化CREB细胞核的快速 (小于 5 min)和节段性的显著增多 ;它们主要分布在双侧背角表层 ~ 层 (2 5 4± 2 0 vs 2 62± 2 3 )、 层(115± 13 )和双侧 ~ 层 (3 46± 2 0 vs3 2 8± 2 6) ;而在对照和炎症组大鼠的胸段脊髓中均未见磷酸化 CREB的增加。在注射CFA诱发一侧炎症或切断一侧坐骨神经的实验组大鼠 ,也可看到至少延续到第三天的强而双侧性的 CREB的磷酸化。这种由一侧后肢伤害性传入引致腰段脊髓中镜像式双侧 CREB磷酸化的出现 ,与一般看到的损伤传入只在同侧脊髓背角引起某些神经化学改变的结果不同 ,可能是人神经损伤后或在实验动物中出现对侧镜像式疼痛过敏现象的基础 相似文献