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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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A survey of primary care residents' attitudes, beliefs, and knowledge and a medical record audit were used to assess barriers to appropriate detection, identification, and management of hypercholesterolemia. Previous studies have focused on either self-reports or audits alone. This study compares survey results to recorded clinical performance. Family practice and internal medicine residents were compared to determine if previous findings were specialty-specific. The results of the survey indicate that, even prior to the publication of the National Cholesterol Education Program, residents demonstrated positive attitudes and appropriate knowledge of risk levels, in contrast with previous reports on practicing physicians. The medical record audit, however, showed that residents were not providing care that approximated their own recommendations for hypercholesterolemia management. Results of the survey and audit demonstrated little or no difference between specialty groups. The results indicated that training in management skills and reducing practice barriers are important to improve resident physicians' management of patients with hypercholesterolemia. The use of a survey and audit provide a useful needs assessment for designing educational programs. 相似文献
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A comparative analysis of radiological and surgical placement of central venous catheters 总被引:3,自引:1,他引:2
Kieran D. McBride Ross Fisher Neil Warnock David A. Winfield Malcolm W. Reed Peter A. Gaines 《Cardiovascular and interventional radiology》1997,20(1):17-22
Purpose To compare the differences in practice and outcome of all radiologically and surgically placed central venous catheters retrospectively
over a 2-year period simultaneously, at a single institution.
Methods A total of 253 Hickman catheters were inserted in 209 patients; 120 were placed radiologically in 102 patients and 133 were
placed surgically in 107 patients. The indication was chemotherapy in 76% of radiological and in 47% of surgical cases; the
remainder were for total parenteral nutrition and venous access.
Results There were 6 (4.5%) primary surgical failures and a further 17 (13%) surgical cases requiring multiple placement attempts.
Pneumothorax occurred once (0.8%) surgically and four times (3.3%) radiologically. There were no radiological primary misplacements
but there were five (3.7%) surgical ones. Catheter or central vein thrombosis occurred in four (3.3%) radiological and five
(3.7%) surgical cases. The rate of infection per 1000 catheter-days was 1.9 in radiologically placed catheters and 4.0 in
surgically placed ones (p<0.001). Average catheter life-span was similar for the two placement methods (100±23 days).
Conclusion Radiological placement is consistently more reliable than surgical placement. There are fewer placement complications and
fewer catheter infections overall. 相似文献
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Two fast magnetic resonance (MR) imaging techniques, advanced Fourier and partial-flip imaging, were used at 0.35 T to examine 21 patients with suspected intracranial lesions; the results were quantitatively compared with a conventional spin-echo study. Both of the fast MR techniques yielded a fourfold reduction in imaging time per section. The advanced Fourier sequence showed contrast that was identical to the conventional spin-echo study with signal-to-noise ratios of 58% and 57% for the first and second echoes, respectively. The partial-flip sequence showed a contrast of 109% and 57% for lesions versus substantia alba, and 107% and 78% for substantia grisea versus substantia alba relative to the first and second echoes of the conventional spin-echo study. The partial-flip sequence was particularly sensitive to magnetic susceptibility; this produced artifacts that may undermine the usefulness of partial flip for routine screening in certain parts of the brain. However, this susceptibility significantly improved the detection of intracranial hemorrhage when compared with the spin-echo sequence, particularly when combined with phase mapping of the partial-flip study. 相似文献