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1.
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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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   
5.
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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经输尿管镜钬激光碎石治疗输尿管结石   总被引:6,自引:1,他引:5  
目的探讨经输尿管镜钬激光碎石治疗输尿管结石的临床效果. 方法 90例输尿管结石,经尿道、膀胱置入10°输尿管镜抵达结石处,将光纤头直抵结石,设置工作能量0.8~1.5 J,频率8~10 Hz,采用连续脉冲方式粉碎结石. 结果3例进镜失败(输尿管镜无法到达结石部位)改开放手术,1例输尿管穿孔改开放手术;86例碎石成功,单次钬激光碎石成功率为95.6%(86/90).手术时间30~80 min,平均55 min.术后住院1~5 d,平均2.5 d.86例随访1~3个月,69例病程<6个月、肾积水<4 cm,肾积水完全消失;17例病程>6个月、肾积水>4 cm,术后患肾均有不同程度积水,但较术前明显改善. 结论经输尿管镜钬激光碎石治疗输尿管结石效果理想,创伤小,并发症少,可作为输尿管中、下段结石的首选治疗方法.  相似文献   
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激光上皮下角膜磨镶术后角膜上皮瓣临床观察   总被引:1,自引:0,他引:1  
目的 观察及探讨准分子激光上皮下角膜磨镶术(Laser subepithel ialkeratomileusis,LASEK)后,角膜上皮瓣的成活率及其影响因素。方法 对行LASEK治疗的42例(80眼)于术后1、2、3天,1、2、3、4周在裂隙灯显微镜下进行角膜上皮瓣的观察。结果 34例(68眼),角膜上皮瓣成活,成活占85%(68/80);未成活8例(12眼),未成活占15%(12/80)。结论 LASEK术后角膜上皮瓣成活率的高低,决定着LASEK的临床疗效,影响其成活的因素是多方面的。其中角膜上皮瓣边缘不整齐、破裂、对位不良、操作时间过长可能是其主要原因。  相似文献   
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目的 :探讨膀胱全切术后可控盲结肠膀胱术的选择及应用。方法 :回顾性分析我科 1 9例可控盲结肠膀胱术患者的临床资料。结果 :1 9例患者术后恢复较好 ,储尿囊平均容量 4 80ml,平均压力 (1 .96± 0 .4 9)kPa ,排尿控制较好 ,插管容易 ,无尿失禁及输尿管反流。结论 :可控盲结肠膀胱术具高容量、低内压、控制排尿等特点 ,可极大提高患者的生活质量 ,其中以可控去带盲结肠膀胱术最为简单、有效 ,值得临床应用  相似文献   
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