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21.
Body art has become common and mainstream. Tattoos and body piercings represent highly individual expressions of identity and personal values. Health care services are enhanced when clinicians understand the anatomy and physiology, common discomforts, and real but rare serious risks of body modification and are prepared to provide compassionate support for individuals’ choices. Special consideration must be given to the needs of childbearing women. By opening channels of communication, clinicians can engage with clients in shared decision making to help those who possess or desire body art take steps to reduce the risk of adverse effects and obtain prompt and effective medical care when problems arise. Through respectful discussion of existing body art, the therapeutic relationship is strengthened, and greater insight into an individual’s health needs may be achieved.  相似文献   
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An important part of fundamental research in catalysis is based on theoretical and modeling foundations which are closely connected with studies of single-crystalline catalyst surfaces. These so-called model catalysts are often prepared in the form of epitaxial thin films, and characterized using advanced material characterization techniques. This concept provides the fundamental understanding and the knowledge base needed to tailor the design of new heterogeneous catalysts with improved catalytic properties. The present contribution is devoted to development of a model catalyst system of CeO2 (ceria) on the Cu(111) substrate. We propose ways to experimentally characterize and control important parameters of the model catalyst—the coverage of the ceria layer, the influence of the Cu substrate, and the density of surface defects on ceria, particularly the density of step edges and the density and the ordering of the oxygen vacancies. The large spectrum of controlled parameters makes ceria on Cu(111) an interesting alternative to a more common model system ceria on Ru(0001) that has served numerous catalysis studies, mainly as a support for metal clusters.  相似文献   
24.
BACKGROUND/PURPOSE: Sensitive skin is a condition associated with reduced tolerance to environmental factors and/or the application of topical products, such as cosmetics. Its pathophysiology has not been fully elucidated and few data are available on its prevalence. The aim of this study was to investigate possible correlation between objective sensitivity and skin surface microrelief. METHODS: During an epidemiological survey conducted for a campaign promoted by International Society of Plastic Dermatology in Italy, 243 adult healthy subjects of both sexes with no evident dermatological disorder but positive to the lactic acid stinging test, were submitted to cyanoacrylate stratum corneum stripping from the volar forearm for the determination of the irregularity of the skin surface microrelief (irregularity skin index (ISI)). RESULTS: A significant correlation was found between intensity of symptoms in stingers and ISI (r(s)=-0.47; P<0.001). CONCLUSION: Sensitive skin is common in the healthy population. ISI can contribute towards the identification of subjects with sensitive skin and the development of more specific skin treatments for this prevalent condition.  相似文献   
25.
Background: Accurate measurement of the QT interval is important for diagnosing long QT syndrome (LQTS), and in research on determinants of ventricular repolarization time. We tested automatic analysis of QT intervals from multiple ECG leads on chest. Methods: Eleven healthy volunteers and 10 genotyped LQTS patients were tested at rest and during exercise with a bicycle ergometer twice 1–31 months apart. Electrocardiograms were recorded with the body surface potential mapping system, and 12 precordial channels were selected for analysis. Averaged QT peak and QT end intervals were determined with an automated algorithm, and the difference QT end minus QT peak (Tp‐e) was calculated. Repeatability was assessed by coefficient of variation (CV) between measurements. Results: Within one test at rest the QT end intervals were highly repeatable with CV 0.6%. In repeated tests CV was 4.4% for QT end interval and 3.5% when the QT interval was corrected for heart rate. In exercise test at specified heart rates, mean CV was 3.0% for QT end and 2.9% for QT peak interval. The CV of Tp‐e interval was 10.2% at rest, and 9.3% in exercise test. Reproducibility was comparable between healthy subjects and LQTS patients. Conclusions: The BSPM system with automated analysis produced accurate and highly repeatable QT interval measurements. Reproducibility was adequate also over prolonged time periods both at rest and in exercise stress test. The method can be applied in studying duration of ventricular repolarization time in different physiologic and pharmacologic interventions.  相似文献   
26.
Gonadotropins have been implicated in the development of epithelial ovarian cancers. These tumors are derived from ovarian surface epithelium (OSE). The purpose of this study was to determine the effects of these hormones on DNA synthesis and spontaneous cell death in primary cultures of OSE and three immortalized OSE cultures. Primary cultures of OSE cells were generated from the ovaries of women with benign disease. The effects of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) on DNA synthesis and cell death were determined using [(3)H]thymidine incorporation and JAM assays. Significant inductions of DNA synthesis were demonstrated with LH in 4/12 (33%) primary cultures of OSE and 2/3 OSE cell lines and with FSH in 4/11 (36%) primary cultures of OSE and 2/3 OSE cell lines. A significant protection from cell death was also observed in the presence of FSH in 2/4 primary cultures of OSE and 1/3 OSE cell lines and in the presence of LH in 1/4 primary cultures of OSE and 2/3 OSE cell lines. The results indicate that while gonadotropins have the potential to induce cell proliferation and protect from cell death in OSE cells in vitro, their effects are variable in OSE cells from different women.  相似文献   
27.
家兔静注人血清白蛋白修饰的尿激酶(MUK)和天然尿激酶(NUK)40000IU后,MUK 的体内过程符合零级速率过程,NUK 则符合一级速率过程,血纤溶活性 MUK 持续100min,而 NUK 仅20~25min。在“功能性”去除肝肾的家兔,NUK 血浓度半衰期延长3~4倍,而 MUK 血浓度下降与正常家兔相似。MUK 及 NUK 在去除纤溶抑制物的优球蛋白成份中纤溶活性相似,但在血浆中 NUK 仅存24~35%的纤溶活性,MUK 则保留了64~85%的纤溶活性。提示肝肾的摄取、代谢和消除能力降低及对血浆纤溶抑制物抵抗力增强,是 MUK 血纤溶活性长时间维持高水平的主要原因。  相似文献   
28.
本文对81例乙型肝炎病人的肝活检组织进行了电镜观察,发现HBsAg的阳性率达93.8%。电镜下,HBsAg细丝不仅有一般的管状细丝型,还有分枝管型和管泡型,而且CAH病人肝组织不易找到HBsAg丝(易见者仅9%),CPH,CLH则多数(79.5%)为易见及可见,二者有高度显著性差异(P<0.01)。  相似文献   
29.
许多昆虫与寄生在昆虫体表或肠道细胞中的微生物建立了共生关系。臭虫、蚜虫、猎蝽等昆虫可以依靠非最佳食物为生,这一是由于其特殊的生存环境,还由于其体内的共生微生物可以帮助合成和补充其食物中所缺乏的必需营养物质。蚊虫也与其肠道中共生细菌有着密切的联系。成蚊喜产卵于富舍细菌的水体中,水体细菌成为蚊虫幼虫的重要食物来源。伊蚊和库蚊幼虫正常生长发育不可缺少细菌,在无菌条件下饲养,蚊虫或其他媒介昆虫不能正常发育至成熟或不能传播人畜疾病。该文对蚊虫与细菌的共生现象以及其在以下几方面的应用进行综述,(1)蚊虫共生细菌的分离与鉴定,(2)共生细菌的形成与传代,(3)共生细菌在昆虫中的分布,并讨论了经过遗传改造的蚊虫共生细菌对蚊虫防治及控制疟疾等由昆虫传播的疾病的应用前景。  相似文献   
30.
目的 探讨磁共振脑表面成像技术在矢状窦旁腩膜瘤手术中的应用价值.方法 分析本院经头颅CT及MRI诊断为矢状窦旁脑膜瘤,利用显微手术技术切除并经病理证实的的22例患者;术前均运用磁共振脑表面成像技术评估与肿瘤关系密切的脑表面回流静脉情况.术中根据成像结果有目的 地保护重要的回流静脉,对比患者手术前后神经功能恢复状况,并进行随访来评价手术效果.结果 22例患者的术前磁共振脑表面成像中脑表面回流静脉与术中所见高度一致.术后患者恢复良好,未出现与静脉损伤相关的并发症.结论 磁共振脑表面成像技术能在术前明确矢状窦旁脑膜瘤与脑表面回流静脉之间关系,可在术前对患者肿瘤表面脑回流静脉做出正确的评估,对脑表面重要回流静脉的保护提供了准确的影像学依据,对患者神经功能的保护及术后恢复起到重要作用.  相似文献   
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