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Background/purpose: Vitiligo and nevus depigmentosus (ND) present similar hypopigmented macules with significantly different prognoses. Although the distinction between the two diseases is important, differential diagnosis relies on medical history and physical examination, which is far from decisive in some cases. The Mexameter® is an objective skin color-measuring device, and has been reported to provide a reproducible and sensitive means of quantifying small skin color differences. In this study, we investigated the usefulness of a Mexameter® for discriminating these diseases.
Methods: A selection of 202 hypopigmented skin lesions (182 from vitiligo and 20 from ND) were the objects of this study. Using a Mexameter, MIs were obtained from lesions and symmetrically located control skin. RMIs, ratios of the MIs of lesional skins to control skins, were calculated.
Results: The mean MIs and RMIs were significantly different for vitiligo and ND. The mean RMI of ND lesions was 74±13, which was significantly higher than that of vitiligo lesions (50±24). No ND lesion had an RMI of <50%.
Conclusion: This study shows that the Mexameter®, an objective pigment-measuring device, can be used to achieve a more accurate diagnosis of hypopigmentary disorders, and that the relative melanin index (RMI), which represents the relative pigment levels, might be a more effective parameter than the melanin index (MI) itself for comparing pigmentation differences.  相似文献   
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Chondroitin sulfates were isolated from the mud snail. For the quantitative analysis of enzymatic digestion products of isolated chondroitin sulfates, strong anion exchange-high performance liquid chromatography (SAX-HPLC) was performed. By the action of chondroitinase ABC, three unsaturated disaccharides 2-acetamide-2-deoxy-3-O-(β-D-gluco-4-enepyranosyluronic acid)-D-galactose (ΔDi-OS), 2-acetamide-2-deoxy-3-O-(β-D-gluco-4-enepyranosyluronic acid)-6-O-sulfo-D-galactose (ΔDi-6S) and 2-acetamide-2-deoxy-3-O-(β-D-gluco-4-enepyranosyluronic acid)-4-O-sulfo-D-galactose (ΔDi-4S) were produced from the mud snail chondroitin sulfates. The analysis showed that relative proportion of ΔDi-OS/ΔDi-6S/ΔDi-4S was 58.7/3.1/38.2. The immunomodulating activity of chondroitin sulfate was examined by cell proliferation assay and these results suggest that it might be a immunosuppressant.  相似文献   
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目的 分析经尿道前列腺电切术(TURP)与经尿道前列腺汽化电切术(TVP)术中、术后常见并发症的原因、预防及治疗,提高手术安全性和有效性。方法 回顾性分析1999年5月-2006年6月我院TURP和TVP术48例并发症患者的临床资料。结果 平均手术时间75min,平均切除组织41g。术中、术后出血20例,电切综合征(TURS)5例,暂时性尿失禁11例,膀胱颈部挛缩5例,尿道狭窄8例,尿路感染7例,膀胱穿孔1例。结论 TURP和TVP是良性前列腺增生症安全有效的外科治疗方法,术前详细采集病史,术中正确操作。术后对病人正确指导及处理可有效减少手术并发症。  相似文献   
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The operating department nurse is subject to many stressors and while there is an optimum level of stress where nurses function at their best, too much may be detrimental both to nurses--and their patients. Jean Sang looks at the subject of stress and discusses the findings of her research.  相似文献   
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We report an uncommon case of solitary, small hepatic angiosarcoma that was initially considered as a hemangioma. We present the imaging findings, with an emphasis on the initial and follow-up CT and MR findings, as well as report on the more suggestive findings of angiosarcoma than those of a hemangioma.  相似文献   
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Sixty six patients with dyspeptic symptoms underwent upper gastrointestinal endoscopy and biopsies for Helicobacter pylori culture. The number of H. pylori isolated increased with age reaching a peak at 51 to 60 years of age. Antral gastritis closely followed by duodenitis accounted for the highest number of H. pylori isolated, (87.5% and 85.7% respectively). In patients with duodenal ulceration only, 57% had H. pylori isolated from their antral biopsies, a result that was just slightly higher than that where no endoscopic diagnosis was made (50%).  相似文献   
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