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31.
目的探讨螺旋CT三维重建及切割软件在诊断颌面部骨折中的应用价值。方法29例颌面部骨折病例,先经螺旋CT扫描,后在工作站上进行三维重建和切割,显示骨折,分析总结二、三维及切割软件在显示骨折方面的效果。结果三维影像在显示浅部颌面部骨折位置,范围,骨碎片移位方面优于二维影像,但在显示深部结构方面不及二维影像;结合使用切割软件可扩大三维重建的应用范围,可同样清楚显示深部的三维结构。结论三维影像可清楚显示颌面部的空间解剖关系,切割软件能扩大三维软件的应用范围,可显示清楚深部结构的三维关系,有重要的临床应用价值。  相似文献   
32.
UV法及Weibull模型评价复方法莫替丁分散片的溶出特性   总被引:1,自引:0,他引:1  
目的 :评价复方法莫替丁分散片在不同测定方法下的溶出特性。方法 :采用转篮法及桨法测定复方法莫替丁分散片的体外溶出度 ,溶液吸收度以紫外分光光度法测定 ;实验数据采用Excel软件 ,以Weibull分布模型求算溶出参数并拟合回归直线 ,用t检验进行统计学分析。结果 :采用转篮法及桨法测定本复方法莫替丁分散片的溶出度 ,其td 值分别为 1 30 6 3及 0 7931min ;直线斜率间存在统计学差异 (P <0 0 1)。结论 :本品溶出过程受测定方法影响较大 ,提示本品的体内溶出过程与胃肠运动密切相关。  相似文献   
33.
多媒体网络教学系统在计算机实验教学中的应用   总被引:5,自引:0,他引:5  
分析了传统计算机实验教学模式下存在的各种弊端,提出在计算机实验教学中应用新的多媒体网络教学模式的必要性,并结合实验教学实践对多媒体网络教学系统的功能和特点进行了详细介绍。  相似文献   
34.
研制质量管理网络版软件,按质量管理规范的要求,运行于药品检验机构质量保证体系,使军队药检机构实行药品检验标准化、规范化、科学化管理.  相似文献   
35.
本文阐述了通过硬件还原技术解决PACS报告工作站存在问题的方法。硬件还原技术的引入实现了报告工作站稳定、高效的运行,降低了软件维护时间与成本,提升了放射科医生的工作效率。  相似文献   
36.
Abstract

The paper provides an introduction to the regulatory landscape affecting a particular category of medical technology, namely standalone software—sometimes referred to as ‘software as a medical device’. To aid the reader’s comprehension of an often complex area, six case studies are outlined and discussed before the paper continues to provide detail of how software with a medical purpose in its own right can potentially be classified as a medical device. The reader is provided an appreciation of how to go about classifying such software and references to support the developer new to the field in locating detailed regulatory support documents and contact points for advice.  相似文献   
37.
38.
??Abstract??Objective To make doctor perform operation accurately on patients with dentomaxillofacial deformity by preoperative simulation based on digital data which was collected by digital software. Methods Fifteen patients had previously undergone 3-dimensional computed tomography and the data from CT scan were input into digital software. We used the software to simulate operations preoperatively including fixing point??osteotomies and movements of jaw bones. The collected information from software was applied to actual operations. Results All the operations had been completed successfully without serious complication. The patients were satisfied with the effect of operation 6 months after operation??with a satisfaction rate of 93.3%. Conclusion The digital simulation technique is a precise method which provides practical and effective basis for establishing the preoperative planning of individual optimal surgical procedure for patients with dentomaxillofacial deformities in orthognathic surgery.  相似文献   
39.
HIV-1 M originated from SIVcpz endemic in chimpanzees from southeast Cameroon or neighboring areas, and it started to spread in the early 20th century. Here we examine the factors that may have contributed to simian-to-human transmission, local transmission between humans, and export to a city. The region had intense ape hunting, social disruption, commercial sex work, STDs, and traffic to/from Kinshasa in the period 1899–1923. Injection treatments increased sharply around 1930; however, their frequency among local patients was far lower than among modern groups experiencing parenteral HIV-1 outbreaks. Recent molecular datings of HIV-1 M fit better the period of maximal resource exploitation and trade links than the period of high injection intensity. We conclude that although local parenteral outbreaks might have occurred, these are unlikely to have caused massive transmission. World War I led to additional, and hitherto unrecognized, risks of HIV-1 emergence. We propose an Enhanced Heterosexual Transmission Hypothesis for the origin of HIV-1 M, featuring at the time and place of its origin a coincidence of favorable co-factors (ape hunting, social disruption, STDs, and mobility) for both cross-species transmission and heterosexual spread. Our hypothesis does not exclude a role for parenteral transmission in the initial viral adaptation.  相似文献   
40.
A method was proposed for determination mass absorption coefficient of gamma rays for compounds, alloys and mixtures. It is based on simulating interaction processes of gamma rays with target elements having atomic numbers from Z=1 to Z=92 using the MCSHAPE software. Intensities of Compton scattered gamma rays at saturation thicknesses and at a scattering angle of 90° were calculated for incident gamma rays of different energies. The obtained results showed that the intensity of Compton scattered gamma rays at saturations and mass absorption coefficients can be described by mathematical formulas. These were used to determine mass absorption coefficients for compound, alloys and mixtures with the knowledge of their Compton scattered intensities. The method was tested by calculating mass absorption coefficients for some compounds, alloys and mixtures. There is a good agreement between obtained results and calculated ones using WinXom software. The advantages and limitations of the method were discussed.  相似文献   
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