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61.
Although tumour vasculature constitutes a biological factor playing a crucial role in the radiation response of tumours, the current procedures of assessment are semiquantitative, typically employing visual examination of stained histological material. Such techniques are also time consuming, and inefficient of extracting essential information on the vascular network. Image analysis has yet to contribute significantly in this direction, and most studies to date focus on blood vessel segmentation through empirical, user-selected thresholds. The present paper proposes an alternative segmentation approach, based on a probabilistic relaxation algorithm, applied in microscopic images of stained tissues. After image partitioning various information is obtained, such as vascular domains and geometrical characteristics of vessels.  相似文献   
62.
ADHD儿童在钟表绘画测验中的执行功能特征   总被引:2,自引:0,他引:2  
目的研究ADHD儿童在钟表绘画(CDT)测试中体现出的执行功能特征。方法对60例ADHD儿童和60例正常对照儿童进行CDT测试,综合分析两组儿童的大脑额叶执行功能的差异。结果ADHD儿童在CDT测试中的时间总分和构造总分低于对照组(3.23±1.40/4.15±0.78,11.2±1.48/11.90±0.76,t=7.742、5.073,P<0.01)。在给定十字位相标定点(3、6、9、12点)后ADHD儿童的钟面构造得分高于给定标定点之前(11.93±0.95/11.19±1.48,t=5.645,P<0.001),但时间设置评分却没有明显的提高(P>0.05)。结论ADHD儿童CDT测试得分偏低体现了其存在计划性、注意调控功能和工作记忆的缺陷,这些缺陷的核心问题是执行功能的缺陷。  相似文献   
63.
原发性肝癌患者抑郁症状与不成熟防御机制的关系   总被引:7,自引:0,他引:7  
目的:了解原发性肝癌(PLC)患者的抑郁症状和不成熟防御机制(IDM)的水平,探讨PLC患者的抑郁症状与IDM的关系。方法:采用流调用抑郁自评量表(CES-D)和防御式方式问卷(DSQ)对PLC患者和健康组各100例进行调查。结果:1)PLC患者中49%可能或肯定有抑郁症状,其中23%肯定有抑郁症状,其发生率高于健康组;2)PLC组的CES-D总分高于健康组;3)PLC组比健康组采用较多分裂和潜意显现机制,采用较少抱怨机制;4)肯定有抑郁症状者比无抑郁症状者采用较多IDM;5)两组CES-D总分与IDM均分呈显著正相关,Pearson r为0.473-0.776,其中PLC组为0.473。结论:抑郁症状是PLC患者常见的负性情绪,医护人员应引起重视,并指导患者采用成熟的防御机制代替不成熟防御机制,预防并减轻患者的抑郁症状,以提高患者的生活质量。  相似文献   
64.
A case of aortic intimal sarcoma with multiple tumor emboli and distal metastasis is reported. All metastasis (adrenal, spleen) were via the arteries. This case also had independent lung cancer. Macroscopically, the aortic tumor did not form a bulged mass, but had linear ulceration with abundant mural thrombi. Poorly cohesive large atypical cells were seen in the intima of the abdominal aorta without invasion into the media. Tumor cells were disseminated into the mural thrombi on the aorta and embolized its branches. In the metastatic tumor or tumor emboli of the distal artery, there were not only large atypical cells, but also the foci of spindle-shaped cells or epithelioid differentiation. Tumor cells in the aorta were immunohistochemically positive for only vimentin. Muscle-specific actin was positive focally for spindle-shaped cells of tumor emboli and metastatic tumors. Furthermore, cytokeratin-positive cells were scatteredly seen. All tumor cells were negative for factor VIII and did not have a histologic or phenotypic analogy with lung cancer. The primary intimal sarcoma in the present case was of undifferentiated non-endothelial intimal stromal cell origin, and may have had multipotential for differentiation. Investigation of the metastatic site was useful for recognizing the features of this tumor.  相似文献   
65.
为探讨“军字1号”工程使用前后的病案首页质量变化,本文通过作者所在医院近八年病案首页的质量调查统计,对“军字1号”工程使用前后的病案首页质量作了详细的对照分析比较,为进一步加强“军字1号”工程中的病案首页质量管理提供经验。  相似文献   
66.
We report on an 8-year-old Japanese boy with Setleis syndrome. The patient had a very characteristic “coarse” facial appearance, bitemporal “forceps marks,” skin aplasia, sparse hair, and skin hypo- and hy-perpigmentation. He also had previously undescribed manifestations, including an aberrant hair pattern of the forehead, linear skin lesions on the forehead, short palpebral fissures, a small skin tag on the right cheek, cone-shaped teeth, and pectus carinatum. Dermatoglyphic studies documented aberrant distal palmar creases (simian crease variant), 8 arches, and reduced total finger ridge count. When serial photographs were reviewed, his facial characteristics became more obvious with increasing age. © 1995 Wiley-Liss, Inc.  相似文献   
67.
An adaptive algorithm is described that groups motor unit action potentials (MUAPs), detected in a composite EMG signal during signal decomposition, and creates partial motor unit action potential trains (MUAPTs). Data-driven MUAP shape and motor unit firing-pattern based criteria are used to form the clusters. An algorithm for estimating MUAPT temporal parameter, which provides accurate estimates even for partially defined trains, is used to obtain firing-pattern information. No a priori knowledge is required regarding the number of clusters or the distribution of their template shapes. The clustering algorithm when applied to real concentric-needle detected MUAP data provides accurate and useful clustering results. Compared to a classical leader-based algorithm, it provides more robust performance, is better able to estimate the true number of motor units represented in a set of detected MUAPs, and obtains more complete and accurate MUAPTs.  相似文献   
68.
目的探讨2668例急诊病房住院患者的临床病例特点,为急诊医护工作提供参考依据。方法选取2015年1月至2018年6月于宣武医院急诊科病房住院的2668例患者,回顾性地采集研究数据,包括性别、年龄、共病受累系统、住院费用、住院时间、住院前及出院前自理生活能力评分。结果1)男性患者入院平均年龄小于女性[(67.2±17.1)岁vs(70.7±17.2)岁](P<0.01)。2)2408例(90.25%)入院患者罹患3种以上共病,共病受累系统主要为呼吸、循环、内分泌。3)患者入院前生活能力评分显著低于出院前生活能力评分(69.42±25.09 vs 78.12±26.13)(P<0.001)。4)Barthel评分与住院时间、住院费用、白蛋白减低、贫血呈负相关。结论急诊病房病种复杂,涉及多学科多专业,病情危重多变,应在临床诊治和护理过程中给予综合、全面的评估,提高患者的治愈率。  相似文献   
69.
In 1998, an epidemic of hand-foot-and-mouth disease and herpangina caused by enterovirus 71 occurred in Taiwan, leaving many fatalities and severely handicapped survivors in its wake. The reasons this rather common pathogen would cause such a large-scale epidemic remain unknown. A seroepidemiological survey to elucidate the epidemiological characteristics of this outbreak, including its incidence and case-fatality rates was undertaken. Microneutralization tests for antibodies against enterovirus 71 were used to screen four collections of serum samples: 1) 202 specimens taken from individuals > or = 4 years old in 1994; 2) 245 specimens collected from individuals of all ages in 1997; 3) 1,258 specimens collected from individuals of all ages in 1999; and 4) sera samples from a birth cohort of 81 children who had yearly blood samples taken from 1988-98. After the maternal antibody had declined, the seropositive rates began to increase with age. Approximately half of all children aged 6 years or older were enterovirus 71 seropositive. Significantly higher seropositive rates were noted in 1999 than in 1997, in children aged 0.5-3 years. The incidence of enterovirus 71 infection during the epidemic was estimated to be 13-22%, with the higher rates in younger children. The case-fatality rate was highest (96.96 per 100,000) in infants aged 6-11 months, and declined in older children. The results showed that enterovirus 71 is endemic in Taiwan. The apparent lack of large-scale enterovirus 71 activity in the 3 years before 1998 might have been the prelude to the epidemic's appearance in 1998, and might suggest that enterovirus 71 infection will reappear every few years. The lack of a protective antibody in younger children may account for the high incidence and case-fatality rate in this age group.  相似文献   
70.
The present paper describes a girl with a small de novo deletion of chromosome 9(p12p13). This deletion has not been published previously. The deleted fragment is clearly outside the region involved in the so-called deletion 9p syndrome. The patient had mild dysmorphic features and feeding problems during the first weeks of life, but is now developing well. Because of the lack of severe clinical features in this patient, we speculate that the deletion may be prevalent in other patients who have no clinical indication for chromosome investigation.  相似文献   
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