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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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BACKGROUND.: Cholesterol atheromatous embolism is a systemic disease resultingfrom cholesterol crystal embolization to many organs, includingthe kidney. Vascular surgery, vascular radiology investigationsand anticoagulation have been identified as inciting factors. METHODS.: Fifteen patients with extensive atherosclerosis, presentingwith simultaneous occurrence of acute renal failure and peripheralischaemic changes were diagnosed as having acute renal failuredue to cholesterol atheromatous embolism. RESULTS.: The patients, 12 men and three women, had an average age of65 years. In one patient, spontaneous occurrence of the diseasewas observed. An inciting factor was identified in 14 patients:aortography in 10, aortic surgery in two, and thrombolysis intwo. Clinical course of acute renal failure was quite variable.Four patients required dialysis; 11 were conservatively managed.All patients had concomitant skin lesions, including digitalmottling, cyanosis and gangrene of the toes, and livedo reticularisof the lower limb and abdomen. Eosinophilia was the most commonlaboratory abnormality. The diagnosis of cholesterol atheromatousembolism was confirmed by tissue examination in eight; in threeit was based on the finding of retinal cholesterol emboli; infourpatients it was made on clinical grounds. Seven patientsdied within 36 months. Death was most commonly from cardiaccauses. CONCLUSIONS.: Since the population at risk for cholesterol embolism is growingand the disease is iatrogenic in origin, we should expect todetect cholesterol embolism with greater frequency as causeof acute renal failure in the future.  相似文献   
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Ruptured petrous carotid aneurysm presenting with otorrhagia and epistaxis.   总被引:2,自引:0,他引:2  
Aneurysm formation and rupture within the petrous internal carotid artery (ICA) is an extremely rare occurrence with approximately 10 such cases in the literature. Etiologies of petrous ICA aneurysms include atherosclerosis, closed head trauma, iatrogenic injury during mastoid surgery, chronic middle ear infections, and congenital causes. Therapeutic options include carotid artery ligation, aneurysm resection with or without reconstruction, and radiographically controlled vessel occlusion. The case of a patient who presented with otorrhagia, epistaxis, and transient focal neurologic signs due to a ruptured petrous ICA aneurysm is presented. The incidence, etiology, and anatomy of these aneurysms is reviewed, and the various tests for determining adequacy of collateral cerebral blood flow are described. Factors that affect the selection of surgical versus radiologic control of these lesions are also discussed.  相似文献   
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A conjugate vaccine against meningococcus A and C was prepared using the non-toxic mutant of diphtheria toxin CRM 197 as a carrier protein. Capsular polysaccharides of Neisseria meningitidis group A and C were hydrolysed and the resulting oligosaccharides were then coupled to CRM 197 in order to obtain conjugates with a carbohydrate content of 25-30%. The final vaccine that contained 11 micrograms of each oligosaccharide and 88 micrograms of CRM 197 was used to immunize mice and rabbits. After the preclinical studies which showed that the vaccine was safe and immunogenic in animal models, a pilot phase 1 clinical trial, blind versus placebo, was performed on adult volunteers. The difference between the incidence of adverse reactions associated with vaccine and placebo administration was not statistically significant. All the volunteers who received the vaccine had a significant increase in antibodies to group A and C meningococcal capsular polysaccharides after the first dose.  相似文献   
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In situ saphenous vein grafts are being used with increasing frequency for bypass procedures involving the femoral and popliteal arteries. Complications of these procedures include anastomotic stenoses and persistent arteriovenous fistulae that may result in failure of the graft. Balloon angioplasty and embolotherapy with detachable balloons were employed successfully in three or four recent cases of patients with complications from in situ grafts. Tailored angiography is essential for evaluating in situ grafts, and interventional techniques are extremely useful for managing complications.  相似文献   
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Winkler  ML; Olsen  WL; Mills  TC; Kaufman  L 《Radiology》1987,165(1):203-207
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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