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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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Experience with the P.A.S.-PORT, a peripherally implanted central venous access device, is evaluated in a retrospective review of 154 patients from July 1991 to June 1994. Blood could not be aspirated from six patients. Complications included temporary minor thrombophlebitis in seven patients (4.5%), symptomatic axillary or subclavian vein thrombosis in five patients (3.2%), clotted port in two patients (1.2%), port pocket cellulitis in two patients (1.2%), and fungal sepsis in two patients (1.2%). In six patients (3.8%) the P.A.S.-PORT had to be removed because of complications. The P.A.S.-PORT facilitated delivery of chemotherapy, parenteral nutrition, blood products, antibiotics, hydration, and blood sampling. It was demonstrated that the P.A.S.-PORT may be inserted and used with a low incidence of complications in gynecologic cancer patients.  相似文献   
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Problem reporting rates of 180 persons with cancer (PWC) were compared with those of their closest in age same sex cancer-free siblings living outside their households for the same time periods. PWC had significantly higher reporting rates for physical, activities of daily living, nutrition, and emotional problems and a significantly lower rate for family problems. Sibling problem reporting rates, which indicate the likelihood that PWC would have experienced similar problems without a diagnosis of cancer, were highest for physical, emotional, employment, and family problems suggesting that noncancer factors are especially likely to play a role in those types of problems. Regression analyses showed that female and younger PWCs tended to report more problems than their siblings suggesting that they were more affected by cancer and its treatments than were other types of PWC.  相似文献   
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Plasma growth hormone concentrations were measured at hourly intervals between 10 p.m. and 8 a.m. the next morning in 15 drug-free chronic schizophrenic male inpatients and 14 healthy males. Growth hormone secretion was significantly lower in the patients as compared with the controls. Growth hormone release peaked around 1 a.m. in the controls, but a growth hormone peak was absent in the patient group. Increased dopamine activity, increased serotonin activity, or both could explain the absence of a nocturnal growth hormone surge in the schizophrenic patients.  相似文献   
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OBJECTIVES: To investigate variation among neonatal intensive care units (NICUs) in prevalence and management of thrombocytopenia in infants <1500 g. STUDY DESIGN: In total 1283 infants &<1500 g admitted to six NICUs over 21 months were prospectively analyzed. Illness severity was measured by the Score for Neonatal Acute Physiology (SNAP). Platelet counts in the first 12 hours after birth and on day 3 of life were abstracted from the infants' medical records. Thrombocytopenia was determined from the lowest platelet count in each of these time periods. RESULTS: There was variability in rates of thrombocytopenia among NICUs, even after controlling for risk factors (e.g., SNAP, small for gestational (SGA) age and maternal hypertension). One site had a high prevalence of thrombocytopenia, but the lowest percentage of infants with thrombocytopenia who received platelet transfusions. After controlling for SNAP, GA, SGA, Apgar score and incidence of thrombocytopenia, the odds of receiving platelets at this site, relative to the site with the highest transfusion rate, was 0.10 (95% CI 0.02 to 0.43). CONCLUSIONS: This multicenter study finds a 10-fold variation among NICU in the administration of platelets to their thrombocytopenic infants that cannot be explained by presence of thrombocytopenia or illness severity.  相似文献   
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Photosensitivity and photodermatitis in childhood   总被引:1,自引:0,他引:1  
Photosensitivity disorders of children are uncommon, except for banal overexposure reactions to sunlight. Although the long-term sequelae of chronic or intense sun exposure are not often seen in children, physicians should advise patients of the harmful effects and irreversible skin damage that results from unduly prolonged sun exposure. Damage accumulates over the years to cause premature aging, senile elastosis, actinic keratoses, and squamous- and basal-cell carcinomas. Besides the pigmentary changes, wrinkles, and skin cancers--genuine sources of altered appearance and morbidity--we now know that sunburned children develop a higher incidence of melanoma, which is not a rare cause of death in young adults. In Australia, where the incidence of melanoma is highest, a strong correlation exists for melanoma in children who get sunburn before the age of 10. Also, the incidence of melanoma is 50 times as great in bikini wearers who get sunburn as in girls who wear one-piece bathing suits.  相似文献   
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