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991.
Occlusion of large atrial septal defects with a centering buttoned device: early clinical experience
EB Sideris M Leung JH Yoon CR Chen R Lochan AM Worms C Rey B Meier 《Canadian Metallurgical Quarterly》1996,131(2):356-359
A feasibility clinical study was conducted for the transcatheter occlusion of large ostium secundum atrial septal defects with the centering buttoned device. The centering buttoned device is a modification of the regular buttoned device in which a centering counter-occluder is sutured at the central 40% portion of the occluder. During centering it is stretched, forming a parachute-shaped structure and pulling the occluder over the center of the defect. During buttoning, the counter-occluder forms a double figure eight, opposing the right atrial side of the atrial septum. Occlusion was performed in 12 patients aged 6 to 56 years. All had been rejected for transcatheter occlusion by the regular buttoned device, because of either their defect size or the lack of adequate septal rim. The defect size varied between 23 and 31 mm, and the device size varied between 45 and 60 mm. Nine had immediate effective occlusions of their defects and three residual shunts. One patient with unbuttoning had hemolysis at 2 weeks and underwent surgery. Early results of the transcatheter occlusion of large atrial septal defects are promising, and larger clinical trials are justified. 相似文献
992.
We studied 722 reexcision scars of benign and malignant lesions (except melanocytic lesions) excised over a 24-month period. The formalin-fixed, paraffin-embedded tissue sections were examined histologically and immunohistochemically. The histological features of melanocytic hyperplasia were present in 59 cases (8%), 56 from the sun-exposed skin of the face and neck and three from the trunk [p < 0.00001]. The most common sites were the nose and lower eyelids, but the forehead was also frequently involved. Of the 59 patients, 41 were women (p < 0.0001). Basal cell carcinoma was the most frequent original lesion in both sexes (80%). No melanocytic hyperplasia was found in 663 cases (298 on the trunk and extremities and 365 on the head and neck). We have seen this reaction pattern following reexcision of melanocytic lesions as well. Thus, interpreting reexcision margins when lentigo maligna or similar lesions are reexcised may be fraught with difficulty. It is important for pathologists and dermatopathologists to recognize this phenomenon because histologically the presence of increased numbers of large melanocytes could be misinterpreted as melanoma in situ. 相似文献
993.
OBJECTIVE: To examine the relative contribution of polymorphonuclear neutrophil (PMN) vs endothelial cell (EC) activation on the adherence and subsequent killing of ECs by PMNs. DESIGN: In vitro comparative studies of PMN-EC adherence and cytotoxicity. SETTING: Research laboratory and the surgical intensive care unit of a tertiary-level university hospital. PATIENTS: Patients with systemic inflammatory response syndrome admitted to the surgical intensive care unit and hospitalized preoperative noninfected surgical patients. INTERVENTION: None. METHODS: Polymorphonuclear neutrophils were isolated from 21 healthy volunteers, 22 preoperative patients, and 30 patients from the surgical intensive care unit with systemic inflammatory response syndrome. The PMNs were activated with lipopolysaccharide, 100 ng/mL (Escherichia coli 0111:b4), for 40 minutes at 37 degrees C before the adherence and cytotoxicity assays. Human umbilical vein endothelial monolayers were stimulated with tumor necrosis factor alpha, 25 ng/mL, and interleukin 1 beta, 15 U/mL, for 3 hours. The PMNs or EC cells were labeled with sodium chromate Cr 51 and used in a standard adherence or killing assay as required. RESULTS: Control and preoperative patient PMN treatment with lipopolysaccharide produced a modest increase in adherence. The PMNs from patients with systemic inflammatory response syndrome showed moderately increased human umbilical vein endothelial cell adherence, and this could not be augmented further with lipopolysaccharide stimulation. There was a marked increase in PMN adherence to EC after EC activation in all study groups (P < .001). Similar to the adherence data, human umbilical vein endothelial cell cytotoxicity was significantly increased in all groups after human umbilical vein endothelial cell activation (P < .01) but not after PMN stimulation with lipopolysaccharide. CONCLUSION: These data suggest that stimulation of ECs is far more important in producing increased adherence and cytotoxicity of EC than PMN stimulation with lipopolysaccharide in all study groups. Therapeutic efforts in patients with systemic inflammatory response syndrome should be focused on the EC. 相似文献
994.
The lateral shift of focus diffracted and reflected beam and resolving power, insertion loss of a five channel grating spectrometer for 25 to 100 GHz are experimentally investigated. And some analysis for these results are also given. 相似文献
995.
张志秀 《山东轻工业学院学报》1996,10(3):14-16
本文分析了一类系统的输出完全能控的充分条件,为多输入多输出系统的输出完全能控性判别,提供了一较迅速的方法 相似文献
996.
双相不锈钢焊接技术状况 总被引:8,自引:0,他引:8
双相不锈钢具有优异的综合性能,应用范围广,其焊接技术独具特点,受到特别关注。本文论述了双相不锈钢焊接的基本原则,焊丝、保护气体及焊接参数的选择等。 相似文献
997.
998.
BOOTSTRAP CONTROL CHARTS 总被引:1,自引:0,他引:1
999.
Weitang Li Zhenghui Li Shifu Zhu Shujun Yin Beijun Zhao Guanxiong Chen 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1996,370(2-3):435-437
Instead of the temperature oscillation method (TOM), a modified vapor growth method was applied in this paper to grow large HgI2 crystals with fewer lattice defects by providing a relatively stable temperature field during growth. And a new processing technique of HgI2 crystals was developed for detector fabrication by merging solution string-sawing and hand-cleaving. The lattice deformations caused during cleaving were reduced greatly by eliminating passivated layers on the sawed crystal platelets before cleaving. 相似文献
1000.
步进式加热炉炉温优化设定模型及软件开发 总被引:1,自引:0,他引:1
针对线材厂步进式加热炉实际工况,提出了基于经验规则的炉温优化设定模型和在线自学习获取知识的思想,并以炉温优化设定模型为核心,开发出加热炉计算机控制系统的优化运行软件。 相似文献