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81.
A review of 174 consecutive patients admitted with a diagnosis of perforated peptic ulcer to eight Hunter Region hospitals during 1979–86 is presented. Among the female admissions, the proportion of patients > 70 years of age was twice that in males. One-third of all perforations were in females who accounted for two-thirds of all perforated gastric ulcers. Multivariate analysis revealed that perforations located in the stomach and older age were both significant independent variables adversely affecting outcome following surgery. In contrast, shock at presentation and delay in operating were not statistically significant independent risk factors.  相似文献   
82.
Summary: Summary. A study was conducted to determine whether the attitudes of medical students to death and caring changed during the 3 months following exposure to cadaver dissection. All first-year students were invited to complete a questionnaire immediately before their initial cadaver dissection experience, after 6 weeks, and after a further 3 months. The questionnaire reflected attitudes to death, violent death, death of someone known to the respondent and caring when someone known to the respondent is seriously injured. Ethnicity and previous exposure to dying has no effect on responses, but overall men students' reactions were significantly less than for women ( P < 0.001). The responses given on the final part of the questionnaire after 3 months were significantly lower than those to most questions in the first part of the questionnaire. The exceptions were those questions where the subject in the given scenario was known to the respondent, where reactions were rated significantly greater ( P < 0.001) in the follow-up questionnaire and can be explained on the basis that they were a personal referent.
Students rapidly develop a coping mechanism which enables them to view cadaver dissection as an occupation quite divorced from living human beings. During these early months of training solicitude decreases for those who die who are unknown to them, but concern for personal referents increases. Educators should be aware of the dramatic change of attitudes among students and the process of professionalization which might influence their caring of future patients.  相似文献   
83.
84.
目的 研究集成电路芯片制造中作业人员的操作特点、接触职业病危害种类以及事故类型。方法 对集成电路芯片制造的生产流程、职业病危害及接触状况的资料进行收集整理。结果 根据生产流程中使用的设备及芯片制造所用原辅材料,论述了生产过程中各设备和操作工序涉及的各类高度、中度毒性化学物质、工艺特殊气体以及电离辐射和非电离辐射等职业病危害因素、作业人员操作特点和易发事故种类。结论 集成电路芯片制造中职业病危害问题值得关注。  相似文献   
85.
目的 探讨 3种类风湿因子 (RF)诊断类风湿关节炎 (RA)、反映病情活动度和疗效的临床意义。方法对关节痛 /关节炎 (A组 )、确诊的RA (B组 )、其它免疫结缔组织病 (C组 )患者和正常人 (D组 )共 6 18例用酶联免疫法进行 3种RF的动态检测并随访观察。结果  4组人群中 3种RF的阳性率和浓度以B组最高 [IgM RF为 92 4 % ,(182 5± 5 1 4 )IU/ml;IgG RF为 6 7 8% ,(2 2 9 7± 75 6 )IU/ml;IgA RF为 78 8% ,(2 35 8± 80 7)IU/ml],组间比较依次为B组 >A组 >C和D组 (均为P <0 0 5 )。B组中高活动期RA患者的 3种RF浓度明显高于其它 3组 (P <0 0 5 ) ,IgM RF和IgA RF在稳定期和低活动期较高活动期均明显降低 (均为P <0 0 5 ) ,而IgG RF变化无显著性。随访 3~ 18个月 ,A组中最后确诊为RA的比率以 3种RF同时阳性者最高 (10 0 0 % ) ,2种RF同时阳性者次之(90 9%~ 93 3% ) ,以单一RF作比较则IgG RF >IgA RF >IgM RF阳性者。结论 早期诊断RA以IgM RF的敏感性最高 ,以IgG RF的特异性最高 ,任何 2种以上RF阳性可提高RA诊断的可靠性 ,RF浓度可作为判断RA活动度及药物治疗效果的指标之一。  相似文献   
86.
The interactive use of magnetic resonance imaging (MRI) techniques is increasing in operating theaters. A study was performed on 17 male company volunteers to assess the neurobehavioral effects of exposure to magnetic fields from a 1.5 Tesla MRI system. The subjects' neurobehavioral performances on a neurobehavioral test battery were compared in four 1-hr sessions with and without exposure to magnetic fields, and with and without additional movements. Adverse effects were found for hand coordination (-4%, P < 0.05; Pursuit Aiming II) and near visual contrast sensitivity (-16% and -15%, P < 0.10; Vistech 6000). The results from the remaining tests were inconclusive due to a strong learning effect. No additional effect from gradient fields was detected. The results indicate that working near a 1.5 Tesla MRI system may lead to neurobehavioral effects. Further research is recommended, especially in members of operating teams using interactive MRI systems.  相似文献   
87.
目的探讨项目记忆和源记忆的神经基础及其是否存在性别差异。方法健康男女各8名,实验材料为504个高频双汉字词,项目记忆和源记忆实验任务,Block设计,GE1.5T采集功能磁共振成像(mRI)数据,用SPM99分析,得到男女脑功能激活图(P〈0.002,体素块〉20)。结果在P〈0.002,体素块〉20时,女性项目记忆激活双前额叶背外侧BA6(激活数目左右侧分别为62和11个),源记忆较多激活左前额叶背外侧BA6/46(激活数目为59个);男性项目记忆激活右前额叶背外侧BA6/46(激活数目为64个),源记忆激活双前额叶背外侧BA6(左右侧分别为9和40个)。结论项目记忆更多激活右侧前额叶背外侧,而源记忆更多激活左侧前额叶背外侧。女性较多地引起左前额叶背外侧激活;而男性较多地引起右前额叶背外侧激活。  相似文献   
88.
38 cases of sarcoma of head and neck region were analysed in a retrospective way in relation to age, anatomic location, histological, clinical profile, and surgical approaches. Compared to other types of head and neck neoplasms, such as squamous cell carcinoma, soft tissue sarcomas have low rates of regional metastases. However the biological behaviour of soft tissue sarcoma is more aggressive specially in paediatric age group. In the present series, CT scan was considered as the primary modality of investigation. Surgery generally has been recommended as the primary method of treatment for achieving local control, except in those high-grade tumours arising in sites not amenable to resection. 3-year and 5-year survival rates in this present series 50% and 31.6% respectively.  相似文献   
89.
一种新的正交参数选优法及其在非线性回归分析中的应用   总被引:2,自引:0,他引:2  
非线性回归分析是工程中经常采用的一种用来估计数学模型参数的方法,该方法能否顺利运用与参数初始值的选择有极大关系。本研究提出一种新的正交参数选优法——阻尼正交表法,它不仅可以保证非线性回归分析算法的顺利收敛,而且能够显著提高后者的收敛速度,进而极大改善非线性回归分析算法的应用性能。本研究的数值试验及心肌造影超声心动图定量分析应用实例表明,作为对传统正交参数选优法的一种改进,阻尼正交表法在科学与工程计算或信号与信息处理领域有着很好的应用前景。  相似文献   
90.
Cutaneous allergy to mustard in a salad maker   总被引:1,自引:0,他引:1  
A case of allergic contact dermatitis to mustard (Brassica nigra) in a salad maker is reported. The sources of skin contact included a commercial salad cream, a vinegrette, and various members of the mustard family, Cruciferae. The Cruciferae family includes many salad vegetables and condiments which contain allergenic isothiocyanates. The extent of skin contact among salad makers and other food handlers may be significant, and sensitization to isothiocyanates from this large family of vegetables may be an important cause of food contact allergy in these individuals.  相似文献   
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