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M Ardigo I Malizewsky ML Dell'Anna E Berardesca M Picardo 《Journal of the European Academy of Dermatology and Venereology》2007,21(10):1344-1350
BACKGROUND: Vitiligo is the most common pigmentary disorder with a global incidence from 0.1% to 2% in different geographical areas. Histopathology and histochemistry have shown the reduction of melanocytes in achromic patches, but microscopic changes of lesional and non-lesional skin are still not completely understood. Reflectance confocal microscopy (RCM), based on the different light reflectance index of cutaneous structures, allowed in vivo, en face microscopic evaluation of superficial skin layers with a resolution similar to skin histology. AIM: The purpose of this study was to evaluate RCM features of lesional and non-lesional skin of vitiligo patients. Moreover, re-pigmented areas were taken into consideration in order to evaluate melanocyte response to ultraviolet B (UVB) radiation. SUBJECTS AND METHODS: Sixteen patients of different phototypes affected by active non-segmental vitiligo and 10 controls were enrolled in the study. In vivo skin imaging was done using a commercially available RCM (Lucid, Vivascope 1500. Re-pigmented areas from 6 to 16 patients (after UVB narrow-band therapy) were also examined. RESULTS: Vitiligo lesions showed the disappearance of the bright rings normally seen at the dermo-epidermal junction. Moreover, non-lesional skin of vitiligo patients showed unexpected changes as the presence of half-rings or scalloped border-like features of the bright papillary rings. In re-pigmented areas after UVB narrow band therapy, the presence of activated, dendritic melanocytes was seen. CONCLUSIONS: Considering our results, and following further studies, RCM clinical applications could be used in the therapeutic monitoring and evaluation of the evolution of vitiligo. 相似文献
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Newell W JohnsonEditor 《Oral diseases》2005,11(1):2-2
The following declaration was agreed by all participants at the conclusion of the 5th World Workshop on Oral Health and Disease in AIDS. It is reproduced here to draw attention to the world's oral health scientists, and others, of the burden that oral disease causes to those who are HIV positive, and to the important role of the dental and allied oral health professions in caring for these individuals and in the research which will underpin improved understanding and care. 相似文献
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Single-antibiotic use for penetrating abdominal trauma 总被引:1,自引:0,他引:1
R M Nelson P R Benitez M A Newell R F Wilson 《Archives of surgery (Chicago, Ill. : 1960)》1986,121(2):153-156
A prospective randomized study compared the use of moxalactam disodium vs clindamycin phosphate and tobramycin sulfate for treatment of 190 patients with penetrating abdominal trauma. Twenty-seven patients were disqualified because of early death or failure to follow the protocol. The patients in each group were comparable regarding the cause and severity of injury. No significant difference was seen in the incidence of intra-abdominal infection between the moxalactam-treated group (13%) and the clindamycin- and tobramycin-treated group (9%). The intra-abdominal infection rate in patients with colon injuries (21%) was significantly increased when compared with the patients without colon injuries (6%), but the antibiotic regimen did not significantly change the infection rate. No evidence of bleeding problems from moxalactam were noted. Changes in prothrombin and partial thromboplastin times appeared to be related to shock rather than the use of moxalactam. The most severe coagulopathies occurred prior to moxalactam therapy and were seen only in those patients who had shock requiring 10 or more units of blood. Moxalactam is as effective as combination (clindamycin and tobramycin) antimicrobial therapy in patients with penetrating abdominal trauma. 相似文献
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The development of a comprehensive, institution-based patient risk evaluation program: II. Validity and reliability of questionnaire data 总被引:1,自引:0,他引:1
The accuracy of historical information derived from self-administered questionnaires must be confirmed. We report the results of studies conducted to assess the reliability and validity of data collected from a comprehensive cancer risk factor questionnaire developed at The University of Texas M.D. Anderson Cancer Center. A comparison of the basic demographic data of a randomly selected sample of 80 respondents and 70 nonrespondents revealed no fundamental ethnic or socioeconomic differences. We verified self-reported past illnesses, surgical procedures, and cancers by reviewing 72 patient charts, using stringent diagnostic criteria for verification. We noted substantial agreement between self-reported and documented illnesses and operations. With the exception of nine patients who misclassified metastatic disease, the verification of primary cancers was excellent. We determined reliability by interviewing 50 of these patients by telephone. Questions with a dichotomous outcome (e.g., smoking status) were reliably answered; however, those requiring quantification (e.g., amount of alcohol consumed) were less accurately reported on interview. While we recognize the limitations of self-administered questionnaires, we believe this program will develop into a comprehensive, standardized, easily accessible patient risk factor data base. 相似文献
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Critically ill patients often demonstrate that whole body oxygen consumption (VO2) is dependent on oxygen delivery (DO2). In this retrospective study, the relationship of VO2 to DO2 in patients with isolated head injury (HI, n = 18) was compared to that in patients with multiple trauma (MT, n = 60) without serious head injury. Mean pulmonary capillary wedge pressure, central venous pressure, arterial PCO2, cardiac index, and oxygen delivery were significantly lower in HI, but oxygen consumption was not different in the groups. In both groups, changes in DO2 (delta DO2) within each patient were significantly correlated with changes in VO2 (delta VO2) in that same patient. This relationship was not different between the HI patients, (delta VO2 = (0.20 +/- 0.02) delta DO2), and the MT patients (delta VO2 = (0.17 +/- 0.01) delta DO2). When these groups were further divided into those with high hematocrit (greater than 32%) and low hematocrit (less than 32%), HI patients with a low hematocrit demonstrated a steeper regression slope, with 26 +/- 3% of the DO2 change being reflected in the VO2 change. This was significantly greater than the slope in HI patients with high hematocrit (13 +/- 3%) and the MT patients at high (19 +/- 2%) or low (16 +/- 2%) hematocrits. These data show a correlation between changes in oxygen delivery and consumption that is similar in both head-injury patients and multiple trauma patients without serious head injury. This relationship was greatest in head-injured patients at low hematocrit. This relationship of VO2 and DO2 in both groups suggests an influence of neurohumoral factors rather than local tissue phenomena.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Patients with xeroderma pigmentosum (XP) have defective DNA repair and a high predisposition to developing abnormalities and neoplasia in the sun-exposed areas of the skin and mucous membranes. The most common tumors reported in patients with XP are squamous cell carcinomas, basal cell carcinomas, and melanomas. Atypical fibroxanthoma (AFX) is a pleomorphic tumor that arises predominantly in the sun-damaged skin of the head and neck regions of the elderly. We describe a unique case of a 6-year-old African American boy with XP who developed an atypical fibroxanthoma and 2 squamous cell carcinomas in the conjunctiva. The clinical and histopathologic findings of AFX are discussed. 相似文献