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Background Perceived age is important to women and is a primary driver for topical product use and facial cosmetic surgery. Changes in facial features and biophysical skin parameters with chronological age and their associations with perceived age have not been described in Asian populations. Objective To investigate the relationship between biophysical properties of the skin, visual features of skin ageing and perceived facial age in Chinese women. Methods Facial photographs were collected of 250 Chinese women, aged 25–70 years in Shanghai, China. The perceived facial age was determined and related to the chronological age for each participant and to a range of visual assessments of skin appearance and objective biophysical measurements of the skin. The profile of changes in these parameters with age was investigated together with the differences in those parameters for women judged to look younger than their chronological age and those judged to look older than their chronological age. Results Large discrepancies in perceived age (up to 29 years) were found in women of the same chronological age. Each objective skin measure and visual assessment parameter had a stronger correlation with perceived age than with chronological age. The strongest relationships to perceived age were for wrinkles and hyperpigmentation. Skin colour, hydration and trans‐epidermal water loss (TEWL) had weaker associations with perceived age. Women judged to look older than their chronological age had significantly higher scores than those judged to look younger for coarse wrinkles and hyperpigmentation across all age groups. The appearance differences between these groups were evident in composite facial images of the same average chronological age. Conclusions We have identified the skin attributes which differ with perceived age in Chinese women. Perceived age is a better measure of the biological age of facial skin than is chronological age in this population.  相似文献   
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International Journal of Paediatric Dentistry 2010; 20: 426–434 Background. The prevalence of molar incisor hypomineralization (MIH) varies considerably around the world; however, few studies have examined MIH in South American countries. Objective. To evaluate the prevalence, severity, and clinical consequences of MIH in Brazilian children residing in rural and urban areas of the municipality of Botelhos, Minas Gerais, Brazil. Methods. Children aged 6 to 12 years (n = 918) with all four‐first permanent molars erupted had these teeth evaluated according to the European Academy of Paediatric Dentistry (EAPD) criteria. The examinations were conducted by two previously trained examiners, and the dental impact caused by MIH was evaluated with the Decayed, Missing and Filled Teeth (DMFT) index (WHO). Results. Molar incisor hypomineralization was present in 19.8% of the 918 children, with a higher prevalence in rural areas. The majority of the defects presented were demarcated opacities without post‐eruptive structural loss, which has been considered as mild defects. Children with MIH had higher DMFT values. Conclusion. Despite the high prevalence of MIH, the severity of the defects was mild. The results indicate a positive association between MIH and the presence of dental caries.  相似文献   
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目的:观察槲皮素(quercetin)体外对肝癌SMMC-7721细胞的生长抑制和诱导凋亡作用,并探讨线粒体在诱导凋亡机制中的作用。方法:以10、30、60和100μmol/L槲皮素作用于体外培养的SMMC-7721细胞,MTT法检测细胞生长抑制率;Annexi-V/PI双染流式细胞仪检测细胞凋亡情况;吖啶橙(acridine or-ange,AO)染色法观察细胞凋亡时形态变化;JC-1染色法检测细胞线粒体膜电位(mitochondrial membrane potential)变化。结果:槲皮素体外能抑制肝癌SMMC-7721细胞的生长(P<0.01),诱导细胞发生凋亡,并呈现量效和时效关系。10、30、60和100μmol/L槲皮素作用72h引起的细胞抑制率(F=343.71,P<0.01)和凋亡率(F=234.17,P<0.01)明显高于对照组。槲皮素作用48h后,AO染色图片可见细胞膜呈泡状膨出和凋亡小体等。凋亡过程中线粒体膜电位下降。结论:槲皮素体外能抑制肝癌SMMC-7721细胞生长,诱导细胞凋亡发生,线粒体膜电位下降在细胞凋亡过程中可能起到重要作用。  相似文献   
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Peripheral nerve disorders may be classified into compressive or entrapment neuropathies and non‐compressive neuropathies. Muscle denervation recognized on MRI may be a useful sign in the diagnosis of peripheral nerve disorders. Acute or subacute denervation results in prolonged T2 relaxation time, producing increased signal in skeletal muscle on short tau inversion‐recovery and fat‐suppressed T2‐weighted images. Chronic denervation produces fatty atrophy of skeletal muscles, resulting in increased muscle signal on T1‐weighted images. This review will outline and illustrate the various ways that muscle denervation as seen on MRI may assist in the diagnosis and localization of peripheral nerve disorders.  相似文献   
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以肺癌病理案例和语义网络技术为基础,结合了统一医学语言系统(UMLS),研究探讨了语义网络技术在电子病历中的实际应用,并最终实现了加入时序性特征的病理案例语义网络的表示。  相似文献   
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目的 探讨肾小球足细胞相关蛋白nephrin和podocin在V型狼疮性肾炎(V-LN)发病中的作用.方法 检测V-LN组11例和特发性膜性肾病(IMN)组8例患者的尿常规、24-h尿蛋白定量、尿补体C3及纤维蛋白原降解产物(FDP)、血脂、血清补体及肝肾功能,并行肾组织活检间接免疫荧光染色,激光共聚焦显微镜观察nephrin、podocin表达的变化.结果 24-h尿蛋白定量、血清白蛋白、肌酐、尿补体C3两组间无统计学差异;V-LN组血脂、血清补体C3、C4及尿FDP均低于IMN组;nephrin、podocin表达两组均减弱,但IMN组更明显.结论 Nephrin、podocin表达减弱可能参与V-LN蛋白尿的发生,但V-LN表达减弱不及IMN明显,推测V-LN蛋白尿的发生可能还有其他机制参与.  相似文献   
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目的探讨儿童颅内肿瘤的临床特点。方法对云南省肿瘤医院及第三军医大学新桥医院2001~2006年间的248例经组织病理学诊断的儿童颅内肿瘤进行回顾性分析。结果幕上肿瘤156例,幕下肿瘤92例。常见的四类肿瘤为:星形细胞瘤(82/248,33.1%)、颅咽管瘤(58/248,23.5%)、髓母细胞瘤(44/248,17.1%)、室管膜瘤(25/248,10.1%),误诊31例,占12.4%。结论儿童颅内肿瘤部位上以幕上为主,病理以星形细胞瘤最常见,误诊率较高。  相似文献   
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