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Photobiomodulation (PBM) therapy is based on the exposure of biological tissues to low‐level laser light (coherent light) or light‐emitting diodes (LEDs; noncoherent light), leading to the modulation of cellular functions, such as proliferation and migration, which result in tissue regeneration. PBM therapy has important clinical applications in regenerative medicine. Vitiligo is an acquired depigmentary disorder resulting from disappearance of functional melanocytes in the involved skin. Vitiligo repigmentation depends on available melanocytes derived from (a) melanocyte stem cells located in the bulge area of hair follicles and (b) the epidermis at the lesional borders, which contains a pool of functional melanocytes. Since follicular melanoblasts (MBs) are derived from the melanocyte stem cells residing at the bulge area of hair follicle, the process of vitiligo repigmentation presents a research model for studying the regenerative effect of PBM therapy. Previous reports have shown favourable response for treatment of vitiligo with a low‐energy helium‐neon (He‐Ne) laser. This review focuses on the molecular events that took place during the repigmentation process of vitiligo triggered by He‐Ne laser (632.8 nm, red light). Monochromatic radiation in the visible and infrared A (IRA) range sustains matrix metalloproteinase (MMP), improves mitochondrial function, and increases adenosine triphosphate (ATP) synthesis and O2 consumption, which lead to cellular regenerative pathways. Cytochrome c oxidase in the mitochondria was reported to be the photoacceptor upon which He‐Ne laser exerts its effects. Mitochondrial retrograde signalling is responsible for the cellular events by red light. This review shows that He‐Ne laser initiated mitochondrial retrograde signalling via a Ca2+‐dependent cascade. The impact on cytochrome c oxidase within the mitochondria, an event that results in activation of CREB (cyclic‐AMP response element binding protein)‐related cascade, is responsible for the He‐Ne laser promoting functional development at different stages of MBs and boosting functional melanocytes. He‐Ne laser irradiation induced (a) melanocyte stem cell differentiation; (b) immature outer root sheath MB migration; (c) differentiated outer root sheath MB melanogenesis and migration; and (d) perilesional melanocyte migration and proliferation. These photobiomodulation effects result in perifollocular and marginal repigmentation in vitiligo.  相似文献   
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BACKGROUNDNasolacrimal duct obstruction leading to epiphora is a common ophthalmologic complaint, and it may derive from amyloidosis in rare cases. There are a few reports about localized amyloidosis, and amyloidosis with involvement and obstruction of the nasolacrimal duct is exceedingly rare. CASE SUMMARYA 54-year-old male presented with a 2-year history of a lump overlying the left lacrimal sac that had grown rapidly for nearly half a year. Physical examination touched a firm lump in the left lacrimal sac. Nasal endoscopy discovered lesions in appearance of sediments with easy bleeding at the entry of the nasolacrimal duct of the left inferior nasal meatus. Computerized tomography scan revealed speckle high density in the left lacrimal sac and the dilated nasolacrimal duct. During an endoscopic exploration and excision, a large number of dacryoliths were exposed. Pathology indicated amorphous pink material and multinucleated giant cell reaction in the fibrous tissue.CONCLUSIONThis case showed amyloidosis in localized form mimicking dacryolith with nasolacrimal duct obstruction. In clinical practice, we should be aware of the possibility of localized amyloidosis in the nasolacrimal excretory system.  相似文献   
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目的 系统评价有关癌症患者心理韧性发展的真实体验,为更好地制定心理韧性干预方案提供理论依据。方法 计算机检索Cochrane Library、Medline、CINAHL、Embase、PubMed、Web of Science、Psyc INFO以及中国生物医学文献数据库、中国知网、维普、万方数据库从建库至2019年6月相关的质性研究。采用澳大利亚乔安娜布里格斯研究所循证卫生保健中心质性研究质量评价标准(2016)对文献进行评价,采用汇集性整合方法进行结果整合。结果 共纳入10篇文献,提炼42个明确的结果,形成8个类别,汇总成3个整合结果。①心理韧性发展是动态循环的过程:危机负性期,调节成长期,积极转化期,循环强化期;②心理韧性的阻碍因素:个体(消极应对,错误认知,症状和体象困扰),环境(传统社会文化,医疗环境,家庭负担);③心理韧性的保护因素:个体(积极心理与应对方式,复原经历,宗教信仰,自我表露,利他主义与行为),环境(家庭因素,医疗照护,人际支持)。结论 心理韧性的发展是动态循环过程,受个体和环境因素影响,医护人员应根据不同阶段的影响因素给予针对性护理措施,促进患者心理韧性的形成和发展,提高患者的生活质量。  相似文献   
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The nuclear content, area and perimeter of the nucleus of lymphocytes in the C.S.F. were determined quantitatively by means of image analysis technique. 26 cases of central nervous system lymphocytic leukemia (CNLL), and 8 suspected cases were studied, other 56 cases who did not have leukemic and neoplastic diseases and had normal C.S.F. lymphocytes were taken as a control. Our data showed that all the mean nuclear content (MNC), mean nuclear area (MNA), mean nuclear perimeter (MNP), and the maximum and minimum nuclear contents of the 2 groups of former patients were obviously higher than those of the contral (P less than 0.01). These results presented suggestion that the image analysis technique can be used for differentiating the leukemic lymphocyte from normal one especially in suspected cases, and thus the diagnosis of CNLL might be improved.  相似文献   
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Immigrants, and especially those recently arrived in host countries, are a high-risk group for tuberculosis. In 2006 in France, nearly half of the new cases of tuberculosis were reported in this group. The incidence rate among people born abroad was about seven times higher than that observed in people born in France (38.9/105 vs 5.2/105). The incidence was also the highest in districts with a high proportion of socioeconomically vulnerable population, such as Paris and greater Paris area. The characteristics of French born and non-French born cases differed. Patients born abroad were less likely to have pulmonary tuberculosis (68.2% vs 78.2; p < 0.001) and were more likely to live in institutions (such as migrant shelters) and to harbor multiresistant tuberculosis strains. A national tuberculosis control program was launched in France in 2007, to decrease the prevalence of tuberculosis in targeted populations.  相似文献   
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(吴永平)(车东媛)(张婉蓉),(李文英)RoleofthePericytesofIntra-acinarPulmonaryArteryintheStructuralRemodelingofPulmonaryVessels¥WUYong-ping;C...  相似文献   
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