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31.
口服法小肠气钡双对比造影对小肠疾病的影像诊断   总被引:1,自引:0,他引:1  
目的:探讨口服法小肠双对比造影检查及病变表现特点。方法:辅以高、低张药物,口服80%(w/v)硫酸钡200ml加经肛门逆行注入空气2000ml进行小肠双对比造影检查,显示双对比小肠影像。结果:147次小肠造影检查中118例成功地用该方法进行小肠双对比造影检查,成功率80.27%,年龄14岁至69岁,平均34.3岁。118例中阳性32例,阳性显现率27.12%,病理证实的25例,占阳性病例的78.13%。不能应用高、低张药物和逆行注气失败的共29例,占19.73%。小肠肿瘤、Crohn's病、Meckel's憩室和回肠末段淋巴滤泡增生症小肠疾病的双对比影像具有特征性表现。结论:(1)此法小肠双对比造影检查简便易行,适合各类有电视X线机的放射科开展。(2)小肠病变在双对比影像上表现特征明显,易于诊断。(3)不能应用高、低张药物和肛门括约肌松弛的患者用此法检查将受到限制。  相似文献   
32.
It is well established that visual display unit (VDU) operators complain of visual fatigue and visual stress during after-work hours. The present study was divided into two parts. In the first part, standard eye examinations were performed on a group of VDU workers (n = 32) and a control group (n = 15); those subjects who were found to have correct vision (n = 16 and 13, respectively) participated in the second part. The eye examinations revealed that on the average, the VDU workers suffered more than twice as many visual impairments as the controls. In those with correct vision, the near point of accommodation was measured at the beginning of the workday at the start of the week, and at the end of the workday, four days later. In the VDU group, the decrease in accommodation was uniformally distributed between zero and 1.0 diopter, whereas among the non-VDU workers, 77% of the decrease was between zero and 0.25 diopter. The dynamic range of accommodation in the VDU workers on the second examination was smaller than on the first. We conclude that some of the visual stress and visual fatigue that developed at work hindered visual activities after work.  相似文献   
33.
医科院校师生对考试现状看法的调查与分析   总被引:2,自引:0,他引:2  
医科院校的考试主要是学科考试。调查显示,教师和学生对目前的学科考试模式评价均不高,存在的最主要弊端是考试方法单一,考试管理不够科学、严谨,考风不好;认为作弊的主要原因在于学生自己学习不努力、社会风气影响以及学校对教师和学生要求不够严格。因此,要搞好考试改革,提高考试质量,必须着重从改革考试方法、加强考试管理的改革与研究、整顿考风、制定科学的成绩评定方法、加强能力考核、实施教考分离等方面进行探索与实践。  相似文献   
34.
根据汉语文字的特点,书写行为的相关因素及我国文化背景的具体情况,设计了一套用于评定汉语失写症患者书写能力的方法,包括自动书写、抄写、听写、看图书写、主动书写及书写相关能力检查6个部分。通过临床应用,初步显示了该检查法在失写症评估中的可靠性和实用性。  相似文献   
35.
ABSTRACT: Background: The percentage of United States’ births delivered by cesarean section has increased rapidly in recent years, even for women considered to be at low risk for a cesarean section. The purpose of this paper is to examine infant and neonatal mortality risks associated with primary cesarean section compared with vaginal delivery for singleton full‐term (37–41 weeks’ gestation) women with no indicated medical risks or complications. Methods: National linked birth and infant death data for the 1998–2001 birth cohorts (5,762,037 live births and 11,897 infant deaths) were analyzed to assess the risk of infant and neonatal mortality for women with no indicated risk by method of delivery and cause of death. Multivariable logistic regression was used to model neonatal survival probabilities as a function of delivery method, and sociodemographic and medical risk factors. Results: Neonatal mortality rates were higher among infants delivered by cesarean section (1.77 per 1,000 live births) than for those delivered vaginally (0.62). The magnitude of this difference was reduced only moderately on statistical adjustment for demographic and medical factors, and when deaths due to congenital malformations and events with Apgar scores less than 4 were excluded. The cesarean/vaginal mortality differential was widespread, and not confined to a few causes of death. Conclusions: Understanding the causes of these differentials is important, given the rapid growth in the number of primary cesareans without a reported medical indication. (BIRTH 33:3 September 2006)  相似文献   
36.
目的 探讨临床表现及骨髓象改变在骨髓转移癌患者诊断中的意义。方法 对41例骨髓转移癌患者的临床资料及骨髓象进行分析,观察主要临床改变。结果 所有病例均在髓片可找到多少不等的成团、成簇的转移癌细胞,且形态学可见明显异常改变。结论 对明确诊断为恶性肿瘤的患者常规骨髓穿刺涂片可早期发现骨髓转移,多部位或多次穿刺涂片可提高阳性发现率。  相似文献   
37.
We present the construction of a homogeneous phantom to be used in simulating the scattering and absorption of X-rays by a standard patient chest and skull when irradiated laterally. This phantom consisted of lucite and aluminium plates with their thickness determined by a tomographic exploratory method applied to the anthropomorphic phantom. Using this phantom, an optimized radiographic technique was established for chest and skull of standard sized patient in lateral view. Images generated with this optimized technique demonstrated improved image quality and reduced radiation doses.  相似文献   
38.
目的通过对无绳胶囊内镜检查情况分析,评价胶囊内镜检查在临床上应用的效果。方法对17例疑小肠疾病或不能耐受胃镜检查的病人或体检者行胶囊内镜检查,并对其结果进行分析。结果所有病人检查无不适感,15例完成小肠检查,2例胶囊分别滞留于食管、胃。7例不明原因胃肠道出血中5例完成小肠检查。均发现了小肠病变。结论胶囊内镜检查是一种无痛苦、无创、安全的上消化道检查,是小肠疾病尤其是不明原因胃肠道出血诊断的首选方法。  相似文献   
39.
近年来,依达拉奉脑保护作用的研究取得了很大进展,尤以对缺血性脑卒中和新生儿缺血缺氧性脑病的防治研究最为深入,而联合治疗策略也得到了广泛的重视.本文就近5年这些热点研究的新进展进行综述.  相似文献   
40.
This study aimed to identify risk factors for type 2 diabetes (T2D) in Korea, a rapidly changing country. Data of 5,132 adults aged 20-85 were used from the 2001 Korean Health and Nutrition Examination Survey. Multiple logistic regression was carried out to identify risk factors for T2D. Three models were specified: (i) socioeconomic and demographic factors (model 1: age, gender, education, poverty income ratio, employment), (ii) behavioral risk factors and covariates (model 2: obesity, physical activity, smoking, alcohol drinking, dietary quality, family history of T2D, co-morbidity) and (iii) socioeconomic, demographic, and behavioral factors (model 3). The prevalence of T2D was 7.4%. Less education (OR 1.41, 95% CI 1.08-1.84), age (OR 2.19, 95% CI 1.56-3.08 in 40-59 yrs, OR 4.05, 95% CI 2.76-5.95 in 60 yrs + comparing to 20-39 yrs) and abdominal obesity (OR 2.24, 95% CI 1.79-2.82) were risk factors for T2D even after controlling for other factors simultaneously. There was a significant association of T2D with ever smoking (OR 1.34, 95% CI 1.06-1.67). The relationship of age with T2D was modified by gender in model 1 and the relationship of smoking with T2D was modified by obesity in model 2. Less educated, older, obese or ever smokers were more likely to have T2D. Gender mediated the relationship of age, and obesity mediated the relationship of smoking, with T2D. Intervention programs for T2D in Korea should take the interactions among risk factors into account.  相似文献   
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