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61.
T Fikrle K Pizinger 《Journal of the European Academy of Dermatology and Venereology》2007,21(1):48-55
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
62.
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
63.
Clinical characteristics of rapidly progressive leuko-araiosis 总被引:1,自引:0,他引:1
S. Tarvonen-Schröder I. Räihä T. Kurki T. Rajala L. Sourander 《Acta neurologica Scandinavica》1995,91(5):399-404
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
64.
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
65.
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
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
66.
本文比较了11例眼球异物CT与X线影像,并经手术摘出异物证实,CT眼球异物检出及定位准确性均优于X线,尤其对球壁异物的定位,而且能显示断层眼球壁轮廓,具有直观效果,CT异物影像比异物明显扩大,应警惕CT伪影可能使球壁异物定位发生误差,CT目前尚不能完全取代眼球异物常规X线检查。 相似文献
67.
A.J. Greenshaw 《Brain research bulletin》1986,16(5):759-761
A BASIC computer program is described which is useful for calculating filling concentrations for ALZET osmotic mini-pumps employed in studies of chronic drug and hormone administration. After the user has entered the required daily dose, the pump parameters and the animals' weights, the program gives the following information: The total quantity of the drug or hormone required for the experiment; the minimum volume and concentration of solution, allowing a 10% margin for error, to serve as a standard that, when diluted, will fill all pumps in the experiment; individual volumes of this solution that, when diluted to a constant volume will yield the required concentrations to fill each of the respective pumps. Use of this program will ensure reliably accurate and very rapid preparations of solutions for mini-pump use. 相似文献
68.
我院现有后勤职工72名,占全院总人数的7%,其中党员12名。党员占后勤职工16%。笔者自担任后勤分管领导以来,一直重视狠抓后勤党员队伍建设,充分发挥其先锋模范作用,增强带头示范效应。提升后勤队伍凝聚力,使得后勤队伍的工作积极性得到较大提高,后勤部门的服务效率、保障功能和职工满意度都取得新的突破。[第一段] 相似文献
69.
河南省传染性非典型肺炎患者胸部X线表现 总被引:1,自引:1,他引:0
目的 :探讨传染性非典型肺炎的X线表现及变化规律。方法 :对河南省临床诊断的 1 5例患者发病后不同时间的系列胸片和CT进行回顾性分析。结果 :1 5例胸部X线病灶初始形态为斑片状 1 1例 (73.3% ) ,大片状 4例 (2 6 .7% ) ;双侧 9例 (6 0 .0 % ) ,单侧 6例 (4 0 .0 % ) ,均为中、下肺野 (1 0 0 % )。动态观察发现病变进展快 ,病变发展到高峰期时间为 4~ 1 4d , x±s(7.7± 3.2 )d ,双侧 1 3例 (86 .7% ) ,单侧 2例 (1 3.3% ) ,两肺叶及两肺叶以上病变者 1 4例 (93.3% )。病变开始吸收时间为 6~ 2 1d , x±s(1 1 .3± 4 .1 )d ;完全或基本吸收时间 8~ 2 6d , x±s(1 6 .4± 5 .0 )d。1 5例经治疗均痊愈出院。住院时间 1 8~ 4 2d , x±s(31 .9± 7.9)d。 结论 :传染性非典型肺炎的胸部X线特点为急性双侧或单侧多叶炎性浸润阴影 ,以中、下野常见 ,进展迅速 ,及时复查胸部X线对临床诊断及判断病情具有重要价值。 相似文献
70.
Suzanne D. LeBlang M.D. Diego B. Nuñez M.D. Luis A. Rivas M.D. Steven Falcone M.D. Susan E. Pogson R.T. 《Emergency radiology》1997,4(4):200-206
The purpose of this study was to evaluate the ability of helical computed tomographic angiography (HCTA) to detect vascular injury in penetrating neck trauma. Thirty-five patients (30 gunshot wounds and 5 stab wounds) were studied prospectively with HCTA. Scans were performed with a 5-mm slice thickness at a 1:1 pitch after injection of 90 ml of nonionic contrast medium (30-second delay) at 3 ml/sec. Results were compared with those for angiography (29), surgery (3), ultrasound (2), and local inspection (1). HCTA correctly revealed 19 normal and 10 abnormal studies. In 8 cases, HCTA revealed irregular vessel margins (3), contrast extravasation (2), lack of vascular enhancement (1), and caliber changes (2). In 2 patients, HCTA revealed indirect signs of injury only. In 6 cases, HCTA findings did not correlate with angiography. HCTA detects both direct and indirect signs of vascular injury. Although indirect findings are more sensitive, the direct evaluation of vessels increases the specificity and has a high negative predictive value. 相似文献