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51.
人眼调制传递函数自动测试装置   总被引:1,自引:0,他引:1  
本文介绍一个用单片机控制的人眼视网膜-大脑系统调制传递函数测量装置,与传统方法不同,该装置调制对比度是利用电光晶体控制激光束强度的来达到的。该装置不但可以测量空间调制传递的函数,还可测量时-空调制传递函数,并以数据和曲线的形式打印输出。  相似文献   
52.
用参与建立数学模型的521例资料和307例没参与建立数学模型的病例资料验证电子计算机监护慢性肝病的程序。以病理学检查、或以3个月至3年的临床观察结果作为诊断的金标准。254例临床诊断作为对照。验证结果表明(1)计算机监护优于临床诊断,(2)本程序敏感度高。  相似文献   
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54.
目的:探讨颅脑外伤严重程度及CT征象与预后的关系,并探讨CT复查的最佳时间及临床意义。方法:回顾性分析80例颅脑外伤的严重程度与初次CT征象的关系,统计分析复查CT发现新病变的数目、程度及时间。结果:颅脑外伤的严重程度与初次CT征象符合率为92.5%(74/80)。外伤后即刻昏迷、CT显示重度复合伤、脑干损伤或弥漫性脑白质损伤的病死率达70.0%(21/30)。1~3d复查CT发现迟发性病变80个,4—7d21个,7d后8个。结论:临床病情与CT征象变化对判断预后有重要意义,颅脑外伤后3、7d是复查CT的最佳时机,出现病情变化应随时复查。  相似文献   
55.
盛敏  张燕  于双妮  金征宇 《中国骨伤》2008,21(5):374-375
浆细胞肉芽肿临床较少见,常发生于肺、眼眶及消化道等部位,发生于骨则罕见。大部分骨的浆细胞肉芽肿发生于颞骨,发生于胸骨者尚少见报道。现将我院胸骨浆细胞肉芽肿1例报告如下。  相似文献   
56.
BACKGROUND: Digital computer analysis of dermatoscopical images has been reported to facilitate the differential diagnosis of pigmented skin lesions in recent years. OBJECTIVE: The aim of our study was to perform digital computer analysis of a set of different melanocytic lesions and compare the objective results. METHODS: The set of 260 melanocytic lesions (150 excised difficult cases (46 melanomas, 47 atypical nevi, 57 common nevi and 110 unexcised common nevi) was automatically analysed by the digital dermatoscopical system microDERM. We searched for differences in asymmetry, size, compactness and colour distribution. Perimeter/area ratio was calculated. RESULTS: The perimeter/area ratio was detected as the most important criterion for differentiation between malignant and benign melanocytic lesions (sensitivity 91.3% and specificity 90.7% for malignant melanomas vs. all benign nevi; sensitivity 91.3% and specificity 80.8% for melanomas vs. clinically atypical nevi). Differences in size of the lesion, shape and asymmetry of colour were found and statistically verified. Using step-wise logistic regression the formula for calculation of probability of malignant nature of every analysed lesion was constructed. CONCLUSION: The perimeter/area ratio is a simple parameter for the differential diagnosis of melanocytic skin lesions.  相似文献   
57.
Summary Based on the gate-related receptor hypothesis, an analysis of kinetics of AN-132, a new antiarrhythmic agent, blockade of cardiac sodium channels and the gate-related receptor which is bound by the drug was performed by computer simulation. Model-predicted apparent rates of onset of AN-132 (30 μmol/L) blocking were 0.051, 0.038, and 0.034 AF−1 at stimulation frequencies of 1.0, 2.0 and 3.0 Hz, respectively. The time constant of recovery from block by AN-132 at resting potential -90 mV was 39.5 s. These findings are in agreement with those experimental data documented. The analysis of gate-related receptor shows that AN-132 binds the inactivation gate-related receptor, and the binding and unbinding are modulated by the inactivation process.  相似文献   
58.
Clinical characteristics of rapidly progressive leuko-araiosis   总被引:1,自引:0,他引:1  
Introduction – 38 patients found to have either pure leuko-araiosis (LA) or LA combined with infarction(s) on computer tomography (CT) in 1989 were re-examined in 1992 in order to evaluate the progression of LA. The follow-up period averaged 3.2 years. Material and methods - The clinical and radiological data on patients in 1989 were collected from hospital records and re-evaluated. The patients were re-examined clinically (including 24 hour ambulatory blood pressure measurement), and neuroradiologically (CT) in 1992 for this study. Results – 11 (29%) patients were found to have significant (rapid) progression of the extent of LA on CT during the follow-up. At baseline, there was no significant difference in the mean number of brain infarctions between the groups with progressing (prLA) and non-progressing LA (nprLA) or between the number of cortical and central infarctions within these groups. At follow-up, the total number of infarctions had increased significantly in both groups, but it was mostly because of the increase in cortical infarctions in the prLA group (p = 0.043) and, conversely, the central ones in the nprLA group (p = 0.011). prLA was found to be related to heart failure (82% vs 37%, p = 0.029) and atrial fibrillation (55% vs 19%, p = 0.047), whereas nprLA was strongly associated with a sudden onset of symptoms (78% vs prLA 18%, p = 0.001) like a-true brain infarction. Other clinical factors, including mean blood pressure and heart rate, did not clearly differentiate between the groups. Conclusion - The results suggest that there are different subgroups of patients with LA associated with various vascular factors. The occurrence of LA is not related to the distribution of infarctions. The progression of LA is not related to the number of brain infarctions or to the simultaneous increase of infarctions on CT.  相似文献   
59.
Background : In order to find the most useful computerized auditing system for the needs of the QE II Hospital surgical department three surgical auditing software programs were assessed. Methods : The Otago University Surgical Auditing Program, the Australian Surgical Auditing Program, and RACS-Audit were trialled for a period of 1 month each. The software programs were evaluated to find the time requirements for data entry, the level of surgical knowledge needed for effective audit information entry, and the perceived usefulness of the generated reports. Results : It was found that the Otago University program best suited the needs of the department. This system was designed for use in a hospital environment with multiple users. The method of data collection was simple and rapid. Entry of data into the program was logical, well structured and able to be performed by both junior medical staff and clerical staff. Reports generated by this system included information in an appropriate format for the departments' morbidity and mortality meetings. Conclusion : Personal computers are an ideal tool for the undertaking of surgical audit. Software programs are designed for different uses and should be critically assessed to ensure that the method of data entry, the time involved, and the reports generated enable an efficient and effective audit to be carried out.  相似文献   
60.
颅颌面形态有限元分析系统的初步建立   总被引:4,自引:0,他引:4  
田杰  杭洽时 《医学争鸣》1997,18(4):327-329
初步建立一个用于颅颌面形态变化研究的有限元分析系统。方法:程序用BorlandC语言编写,对临床常用的X线头颅定位片进行分析,将呆分析的头颅定位片描在硫酸纸上,用图形数值化仪把节点输入计算机。根据有限元分析法的原理,将头颅定位片上的颅颌面结构份割许多三角形单元,用应变张量来描述颅颌面形态变化。  相似文献   
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