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991.
Anti-phospholipid antibodies (aPL) are concerned with many central nervous system diseases in systemic lupus erythematosus (SLE). However, no report has described the relationship between aseptic meningitis and aPL in SLE. We report a case of SLE with aPL, presenting cerebral infarction and aseptic meningitis. A 14 year old female with SLE with aPL experienced cerebral infarction and recurrent aseptic meningitis. Combination therapy with steroids and aspirin improved the condition and prevented relapses. The aPL are associated with cerebral infarction, even in young patients with SLE. In addition, aPL may induce aseptic meningitis in SLE. 相似文献
992.
An arterial graft holder was designed to facilitate coronary artery bypass grafting using arterial conduits. It is possible to open the heel of the arterial conduit and stitch the most difficult angle of the anastomosis under optimal visualization. This internal thoracic artery holder is atraumatic and protects the arterial conduit wall from crush injuries caused by vascular forceps. Anastomosis without the endothelial injury may provide long-term patency of the coronary artery bypass graft. 相似文献
993.
994.
J Hatazawa E Shimosegawa T Satoh H Toyoshima T Okudera 《Canadian Metallurgical Quarterly》1997,28(10):1944-1947
BACKGROUND AND PURPOSE: We examined whether hemodynamic and metabolic abnormalities in the cerebral white matter, basal ganglia, and thalamus are associated with asymptomatic white matter lesions (WML) depicted on MR images. METHODS: A positron emission tomographic study with H2(15)O, C15O, and 15O2 was performed in eight normal control subjects without any WML (mean +/- 1 SD age, 68.5 +/- 10.2 years) and in 15 asymptomatic subjects with WML (71.3 +/- 8.5 years) to measure regional cerebral blood flow (CBF), cerebral blood volume, oxygen extraction fraction (OEF), and oxygen metabolic rate. RESULTS: In the cerebral white matter in the asymptomatic subjects with WML, significantly lower CBF (20.3 +/- 3.9 mL/100 mL per minute; P < .05) and significantly higher OEF (0.43 +/- 0.08; P < .05) were found compared with those for control subjects (23.5 +/- 2.6 mL/100 mL per minute and 0.37 +/- 0.06, respectively). The severity of WML was not related to the magnitude of hypoperfusion. In the basal ganglia, significantly lower CBF (44.9 +/- 6.9 mL/100 mL per minute; P < .01) and significantly higher OEF (0.54 +/- 0.08; P < .01) were found in the WML group than in control subjects (70.1 +/- 12.0 mL/100 mL/min and 0.39 +/- 0.03, respectively). In the thalamus, there was no significant difference in CBF and OEF between the control and WML groups. CONCLUSIONS: Hypoperfusion of the cerebral white matter and basal ganglia in asymptomatic WML subjects may be induced by the arteriosclerosis of long penetrating medullary arteries and lenticulostriate arteries but may not be directly related to the production of WML. The role of hypoperfusion in the production of WML and acceleration of its development remains to be elucidated. 相似文献
995.
Autonomic nervous system activity in essential hypertension: a comparison between dippers and non-dippers 总被引:1,自引:0,他引:1
This study examines whether race is a significant determinant of the diagnoses of acute myocardial infarction or angina pectoris in patients with symptoms suggestive of acute cardiac ischemia. The study population was comprised of 3401 (34%) African-American and 6600 (66%) white patients who presented to emergency departments with symptoms suggestive of acute cardiac ischemia. The main outcome measure was a diagnosis of acute myocardial infarction or angina pectoris. African Americans were younger, predominantly female, and more often had hypertension, diabetes mellitus, or smoked. The diagnosis of acute myocardial infarction was confirmed in 6% of African-American and 12% of white men, and in 4% of African-American and 8% of white women. After adjusting for age, gender, medical history, signs and symptoms, and hospital, African Americans were half as likely to develop acute myocardial infarction and were 60% as likely to have acute cardiac ischemia. Despite having less acute cardiac ischemia, African Americans in this study had high risk levels for coronary artery disease. 相似文献
996.
997.
Using circular dichroism, the helix contents of sodium poly(L -glutamate) (PLGNa) and poly(L -lysine) hydrobromide (PLLHBr) in their weak and strong polyelectrolyte complexes have been estimated in aqueous alcohol solutions. Helix (de)stabilization observed in the systems is compared with earlier results on the PLGNa/PLLHBr polyion complex. 相似文献
998.
考虑到亮度变化和颜色纯度的图像分割法 总被引:4,自引:0,他引:4
提出了一种新的考虑到亮度变化和颜色纯度的图像分割方法.使用HIS颜色空间来取得象素的颜色信息.当饱和度和亮度值较低时,色彩值会非常敏感,用颜色纯度作色彩值的加权值.不但考虑了像素的属性,还考虑了像素群的属性.图像先被分成块,块的平均值和方差值作为像素群的属性.用基于块的领域扩张来进行图像分割.用向量距离和相对位置信息把小的对象合并到大的对象中.实验结果证明,该方法适用于多种图像. 相似文献
999.
Daisuke Yamane Takaaki Matsushima Toshifumi Konishi Hiroshi Toshiyoshi Kazuya Masu Katsuyuki Machida 《Microsystem Technologies》2016,22(3):459-464
This paper reports a novel dual-axis microelectromechanical systems (MEMS) capacitive inertial sensor that utilizes multi-layered electroplated gold. All the MEMS structures are made by gold electroplating that is used as a post complementary metal-oxide semiconductor (CMOS) process. Due to the high density of gold, the Brownian noise on the proof mass becomes lower than those made of other materials such as silicon in the same size. The single gold proof mass works as a dual-axis sensing electrode by utilizing both out-of-plane (Z axis) and in-plane (X axis) motions; the proof mass has been designed to be 660 μm × 660 μm in area with the thickness of 12 μm, and the actual Brownian noise in the proof mass has been measured to be 1.2 \({\upmu}{\text{G/}}\sqrt {\text{Hz}}\) (in Z axis) and 0.29 \({\upmu}{\text{G/}}\sqrt {\text{Hz}}\) (in X axis) at room temperature, where 1 G = 9.8 m/s2. The miniaturized dual-axis MEMS accelerometer can be implemented in integrated CMOS-MEMS accelerometers to detect a broad range of acceleration with sub-1G resolution on a single sensor chip. 相似文献
1000.