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目的:探讨靶重建放大扫描技术对肺孤立性结节病变的诊断价值。方法:对63例患者先行常规CT平扫,选定结节处为兴趣区,行薄层靶重建放大扫描,层厚、层距为2mm,FOV为160。结果:42例恶性病变中有37例表现为深分叶,占88.1%;21例良性病变中有15例表现为浅分叶,占71.4%。恶性结节中15例内部出现条状低密度支气管征;7例出现血管集中征;8例出现空泡征;病变内部出现液化坏死13例,其中恶性病变ll例。22例出现钙化,包括12例良性病变和10例恶性病变。2例错构瘤内均见小面积脂肪性低密度影。结论:靶重建放大扫描比普通CT扫描可提供更多的信息,对良恶性病变的鉴别诊断有一定价值。恶性病变大多数为深分叶,良性病变大多数为浅分叶或无分叶。  相似文献   
4.
脑干、三叉神经及大脑动脉环的可视化研究   总被引:2,自引:0,他引:2  
目的 建立人体脑干、三叉神经及大脑动脉环的可视化数字模型。方法 采用首例中国数字化可视人体数据集,在SGI工作站上对脑干及其周围毗邻结构进行计算机三维重建并立体显示。结果 获得人体脑干、三叉神经及大脑动脉环等器官组织的三维重建结构,可对其进行任意径线和角度的适时三维测量。结论 首例中国数字化可视人体数据集能够提供完整而精确的解剖断面数据,脑干及其毗邻的三叉神经、大脑动脉环的可视化模型准确反映出该区域复杂的解剖学结构特点及其相邻器官间的空间毗邻关系,可为该区域的疾病的影像诊断和外科治疗提供形态学依据。  相似文献   
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An image processing system for application to studies of the temporal and spatial parameters of movement during swallowing and speech is described. Image sequences from videotape are digitized for computerized manipulation and analysis in an attempt to improve on conventional visual inspection. The system is “interactive” or “event-driven”: after executing a function, the computer waits for guidance from the user who controls the program through keyboard and mouse input, selecting options from menus and responding to prompts. The analyst alters image clarity by the application of filters and heightens contrast through video enhancement. A technique called “remapping” reduces head motion and provides uniform spatial scaling. Animated sequences of images are used, as opposed to frame-by-frame analysis, to preserve temporal context and increase efficiency of measurement. Low cost off-the-shelf personal computer hardware is used along with original software tailored to the application.  相似文献   
6.
This report describes a technique in which deep-seated CNS neoplasms, the volume and shape of which had been determined and stereotactically localized by computer reconstruction of CT data, were vaporized with a carbon dioxide laser attached to a stereotactic frame. The clinical results with 6 patients treated by this technique are presented.  相似文献   
7.
目的:评价无痛麻醉技术的临床麻醉效果,寻求一种更有利于手术进行的局麻技术。方法:选择120例就诊于齿槽外科门诊需要拔牙的患者,将其随机分为对照组和实验组,每组60例。对照组施常规局麻,实施组施无痛麻醉技术,观察每组麻醉结束、术中及术后的血压、心率变化。结果:对照组与实验组对比,术中、术后观测指标的变化无显著性差异,麻醉结束后的观测指标15以下者无显著性差异,15岁以上者有显著性差异。结论:无痛麻醉技术与常规的局麻技术一样可以达到麻醉的目的,无痛麻醉可减少麻醉注射中因疼痛所引起的血压、心率的变化。  相似文献   
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We have developed a computerized neuromuscular monitoring system (NMMS) using commercially available subsystems, i.e., computer equipment, clinical nerve stimulator, force transducer, and strip-chart recorder. This NMMS was developed for acquisition and analysis of data for research and teaching purposes. Computer analysis of the muscle response to stimulation allows graphic and numeric presentation of the twitch response and calculated ratios. Since the system can store and recall data, research data can be accessed for analysis and graphic presentation. An IBM PC/AT computer is used as the central controller and data processor. The computer controls timing of the nerve stimulator output, initiates data acquisition, and adjusts the paper speed of the strip chart recorder. The data processing functions include establishing control response values (when no neuromuscular blockade is present), displaying force versus time and calculated data graphically and numerically, and storing these data for further analysis. The general purpose nature of the computer and strip chart recording equipment allow modification of the system primarily by changes in software. For example, new patterns of nerve stimulation, such as the posttetanic count, can be programmed into the computer system along with appropriate data display and analysis routines. The NMMS has functioned well in the operating room environment. We have had no episodes of electrocautery interference with the computer functions. The automated features have enhanced the utility of the NMMS. The prime advantages of this system are (1) the ability to customize its features by altering its controlling programs, (2) the ready availability of the hardware and software, (3) the general purpose nature of the system, so that it is not limited to this one application, and (4) the adaptable nature of the system.  相似文献   
9.
To reduce the effect of electrode position variations on the diagnostic interpretation of an ECG, ECG and VCG interpretations were combined. The reduction was assessed by generating ECGs with displaced electrodes for a group of subjects using Body Surface Potential Maps (BSPMs). VCGs were reconstructed from the ECGs. The group consisted of normals, cases with myocardial infarction (MI), and with left ventricular hypertrophy (LVH). The effects of four types of electrode position changes were assessed for the diagnostic categories MI and LVH. The combined interpretation proved to be less sensitive to large changes than either the ECG or the VCG interpretation alone. The number of small changes increased for the combined interpretation. The combined interpretation showed higher agreement with a human expert than the ECG interpretation alone.  相似文献   
10.
Over a 12 year period, 25 psoas abscesses occurring in 17 patients were managed at Royal Perth Hospital (900 bed hospital). Symptoms were present, on average, for 5 weeks prior to diagnosis, which was typically confirmed by computerized tomography. Fifty-nine per cent of cases were primary and percutaneous drainage effected a cure in 80% of all cases. Percutaneous drainage resulted in a non-significant trend towards shorter inpatient stay.  相似文献   
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