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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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P Férnandez-Calle J A Molina F J Jiménez-Jiménez A Vázquez M Pondal P J García-Ruiz D G Urra J Domingo R Codoceo 《Neurology》1992,42(5):1064-1066
To elucidate the possible role of vitamin E in the pathogenesis of Parkinson's disease (PD), we compared serum levels of alpha-tocopherol (vitamin E), measured by high-performance liquid chromatography, and the vitamin E/cholesterol ratio of 42 Parkinson's disease (PD) patients using their spouses as the control group. The serum levels of vitamin E did not differ significantly between the groups (13.84 +/- 0.56 micrograms/ml for PD and 14.80 +/- 0.57 micrograms/ml for controls), nor did the vitamin E/cholesterol ratio (0.64 +/- 0.03 for both groups). There was no influence of antiparkinsonian therapy on vitamin E or the vitamin E/cholesterol ratio. Serum levels of the vitamin E and vitamin E/cholesterol ratio did not correlate with age, age at onset, scores of the Unified Parkinson's Disease Rating Scale or the Hoehn and Yahr staging in the PD group. These results suggest that serum vitamin E concentrations do not play a role in the pathogenesis of PD. 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
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高效液相色谱法测定右旋儿茶素血浆浓度及药代动力学参数 总被引:1,自引:0,他引:1
本文建立了体液中右旋儿茶素的RP-HPLC测定方法。采用C_(18)键合相硅胶为填料的固相提取柱进行样品预处理,右旋儿茶素的提取回收率为79.8%.应用二极管阵列检测器对色谱峰纯度进行鉴定。该法精密度好,方法回收率近100%,日内、日间的变异系数为2.4~5.6%,血浓69.6~1160 ng/ml范围内呈线性关系,r=0.9993。家兔静注右旋儿茶素18mg/kg,其药代动力学过程符合二室模型,分布相半衰期为0.129 h,消除相半衰期为1.19h。 相似文献
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Gilberto Goissis Sergio Akinobu Yoshioka Domingo Marcolino Braile & Vladimir Donizeti Aparecido Ramirez 《Artificial organs》1998,22(3):210-214
This work describes the results of the controlled crosslinking of collagen matrices by glutaraldehyde based on a double protection strategy, glutaraldehyde acetals and lysine protonation due to the acidic conditions of acetal formation. Materials crosslinked by this approach were characterized by thermal stability comparable to those obtained by conventional procedures with mechanical properties expected for bioprosthesis manufacture and with a higher stability toward collagenase hydrolysis. The integrity of the microfibrillar structure was confirmed by optical and scanning electronic microscopy. The results indicate that the glutaraldehyde acetals procedure may be of potential use for the crosslinking of bovine pericardium used in the manufacture of bioprosthetic devices. Advantages may be related to the production of materials with homogeneous crosslinking distributions, associated with better definition in the nature of the chemical link that they introduce, due to a better distribution of glutaraldehyde within the tissue matrix before the crosslinking reaction is allowed to occur. As a result, materials with improved biological and mechanical properties are expected. 相似文献
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Carcinoma of the hepaticopancreatic ampullar region: role of US 总被引:3,自引:0,他引:3
Hepaticopancreatic ampullar tumors are so called because they are located at the confluence of the bile duct, pancreatic duct, and duodenum. Jaundice is an early sign of the disease and often leads to early diagnosis and favorable prognosis compared with other tumors that occur in this area. Of eight patients who underwent ultrasound (US) in the past 5 years, six (75%) were found to have tumor. The sizes of the tumors ranged from 1.6 to 2 cm. An intraluminal, polypoid mass in the distal part of the common bile duct was seen in four patients. In the other two patients, a sharply delineated mass gave rise to abrupt termination of the distal duct. Improved US resolution, more experience with this modality, and accurate diagnosis of these tumors with US will contribute to improved detection and prompt treatment. 相似文献