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101.
Objective: Increased dimension of the aortic root and proximal aorta is considered a significant risk factor for catastrophic events that involve the ascending aorta. The objective of this study was to determine the possible correlation between pre-dissection aortic diameter and the occurrence of Stanford type A aortic dissection. Methods: Samples of dissected ascending aortas were obtained from 220 patients at the time of their operation. Two groups were identified: patients with connective tissue disorders (Group 1, n = 94) and those without (Group 2, n = 126). Measurements of the true (intimal) lumen were conducted and extrapolated as reliable approximation of pre-dissection aortic diameter. The possible association of intimal diameter with anthropometric and demographic data was analyzed. Results: Median aortic diameter was, respectively, 41.8 and 41.3 mm for patients with and without connective tissue disorders (41.4 mm for the entire cohort). Data analysis indicated that 57% of patients had aortic diameter above 40 mm, while patients with frank aneurysm accounted only for 10%; this proportion was higher in Group 1 compared to Group 2 (17.2% vs 4.7%). Poor or no correlation was demonstrated between aortic size and any of the anthropometric or demographic variables essayed. Significant subgroup differences were found among patients with a history of cigarette smoking, hypertension, diabetes, chronic renal insufficiency, and bicuspid aortic valve. Conclusion: Although aortic diameter remains a strong indication for preventive surgery in patients with inherited connective tissue disorders, acute aortic dissection occurs rarely in the setting of true ascending aortic aneurysms, and despite normal or near-normal aortic size in more than one-third of subjects. Dissection superimposing on small aortic diameters can be regarded as an expression of substantial functional tissue susceptibility to aortic catastrophic events.  相似文献   
102.
Congenital 21-alpha hydroxylase deficiency is a syndrome characterized by a cortisol synthesis deficiency and, rarely, by testicular masses. We present a case of bilateral nodular hyperplasia of the testis without adrenal hyperplasia in a patient affected by 21-alpha hydroxylase deficiency. This mass mimicked a testicular tumor and made differential diagnosis with a Leydig cell tumor extremely difficult. Multiple hard nodules (1 cm in diameter) could be palpated in both testes but were more prominent on the right. After an unsuccessful 30-day trial of an adrenocorticotropic hormone suppression regimen with dexamethasone (0.5 mg/qid), a right total orchifunicolectomy was performed. The final histological diagnosis was that of multiple, well-circumscribed nodules consisting of cord-like and microalveolar-like gonadal stroma, typical of an adrenogenital syndrome, and fibrosis. Differential diagnosis between testicular nodules in patients with congenital adrenal hyperplasia and Leydig cell tumors is a major clinical challenge. In cases of cortisol suppression resistant testicular masses, a serum adrenal hormone profile obtained from the gonadal vein and histology of the testicular nodule (with parenchyma sparing surgery) are recommended to obtain a correct diagnosis.  相似文献   
103.
All patients undergoing heart surgery experience a certain amount of nonspecific myocardial injury documented by the release of cardiac biomarkers and associated with poor outcome. We investigated the role of unipolar radiofrequency ablation of atrial fibrillation on the release of cardiac biomarkers in 71 patients undergoing mitral valve surgery and concomitant left atrial ablation case-matched with 71 patients undergoing isolated mitral surgery. The study was powered to detect a 3 ng/mL difference. There was no difference between the 2 groups in terms of cardiac troponin I (10 +/- 5.3 versus 12 + 10.4 ng/mL; P = 0.7) or creatine kinase-MB (50 +/- 21.8 versus 57 +/- 62.0 ng/mL; P = 0.5) release. Postoperative peak cardiac troponin I levels had univariate associations with the duration of cardiopulmonary bypass (P = 0.002) and aortic cross-clamping (P = 0.001) and with the surgical technique (15 +/- 12 ng/mL for mitral valve replacement versus 9 +/- 4.8 for mitral valve repair; P = 0.0007) at univariate analysis. Mitral valve replacement was the only independent predictor of postoperative peak release of cardiac troponin I identified with multivariate analysis (P = 0.005). Radiofrequency ablation of atrial fibrillation does not significantly increase cardiac biomarker release compared with isolated mitral surgery; mitral valve repair is associated with less release of cardiac biomarkers compared with mitral valve replacement.  相似文献   
104.
Eruptive Vellus Hair Cysts: Case Report and Review of the Literature   总被引:1,自引:0,他引:1  
A 6-year-old Caucasian girl had dozens of asymptomatic, flesh-colored, 2- to 5-mm eruptive vellus hair cysts. These papules on the buttocks, thighs, and groin increased in number for three months. Histologic examination revealed poorly defined, keratin-filled cysts in the upper middermis, containing numerous transversely or obliquely cut portions of vellus hair. The histopathologic differential diagnosis with other epithelial cysts containing hair shafts is debated, and new clinical differential diagnoses are proposed. Review of the literature suggests that eruptive vellus hair cyst is not a rare disorder, but its frequency is probably underestimated due to paucity of symptoms. Nevertheless, the clinical relevance of some of the differential diagnoses should convince clinicians to obtain histologic confirmation.  相似文献   
105.
We have studied a group of 104 patients with pompholyx, to investigate the relationship between allergological factors and its etiopathogenesis. The following examinations were performed: blood sampling (routine tests and IgE levels), allergological tests (patch, prick, intradermal, and oral provovation tests with nickel sulphate), skin biopsy to exclude pemphigus vulgaris or bullous pemphigoid. An accurate history of familial and personal allergic diathesis was enquired for and various possible aggravating factors (season, microclimate, perspiration and emotional stress) were considered. The results were age and sex-matched with a healthy control group (208 subjects). We found familial and personal atopic diathesis in 50% of patients versus 11.5% of controls (p less than 0.001); 39 patients (37.49%) also had high levels of IgE. Nickel sulphate was the allergen with the highest positivity on patch testing: 20.19% versus 6.25% of the control group (p less than 0.001). The % of patients allergic to nickel reached 26%, including those (6 patients) reacting to the oral provocation test. Season (43 patients) and hyperhidrosis (38) were the aggravating factors most commonly claimed. We detected no correlation between age, sex, grading of pompholyx and the allergological parameters investigated. Though several different allergological findings have previously been reported in dyshidrosis, their role in its pathogenesis has not yet been fully explained. We think that different haptens or antigens can produce the same clinical and histological picture of pompholyx in predisposed subjects.  相似文献   
106.
107.
This article describes a soft tissue surgical modification--the trap door technique--used to enhance contemporary patient esthetic expectations and preserve periodontal health longitudinally. This surgical modification is greatly indicated for single-stage single and multiple implant surgery to preserve the integrity of the papillae and eliminate buccal soft tissue concavity. This procedure also addresses the issue of interproximal papillary development to obviate the presence of a black triangle. The technique is very effective in cases of minimal interproximal bone loss, it does not require autogenous bone harvesting, and is therefore less invasive and well accepted by the patient.  相似文献   
108.
BACKGROUND: Simulators of malignant melanoma comprise a heterogenous group of melanocytic and nonmelanocytic lesions of the skin. Among frequent clinical mimickers of melanoma are injured melanocytic nevi. Any change in the clinical appearance of a pre-existing nevus should alert the clinician to exclude the possibility of malignant transformation in order to early identify a lesion at a stage when complete cure can still be achieved. OBJECTIVE: The purpose of this study was to present the clinical, dermoscopic and histopathologic findings of a series of acquired melanocytic nevi which abruptly developed a pigmented peripheral halo, presumably following minor trauma. METHODS: A series of 6 cases of acquired melanocytic nevi which suddenly developed a targetoid halo were included in the study. All lesions were evaluated by dermoscopy. Three cases were surgically removed at different stages of evolution and submitted to histopathologic examination. In all cases, follow-up was obtained. RESULTS: All the lesions arose on trauma-prone skin sites of young women. The sudden development of an asymptomatic, targetoid halo on a long-lasting, acquired exophytic nevus was the main presentation. Whereas the central nevus persisted, the ecchymotic halo ultimately disappeared. Histopathologic examination disclosed changes of the traumatized nevus in the central part, whereas the ring showed hemorrhage and hemosiderin deposits. Increased numbers of small vessels with hobnail characteristics were associated features. CONCLUSIONS: Targetoid hemosiderotic nevus is a distinctive clinicopathologic variant of traumatized acquired melanocytic nevus which should be included in the list of clinical simulators of melanoma.  相似文献   
109.
We report a 2-year-old girl with diffuse pustular eruptions occurring in close association with respiratory tract infections. The pustular eruption had different clinical characteristics over time, evolving from circinate to von Zumbush pustular psoriasis, and finally to subcorneal pustular dermatosis. Treatment with acitretin 1 mg/kg/day gave good results. A relapse showing striking clinical characteristics of subcorneal pustular dermatosis was treated with dapsone (1 mg/kg/day) followed by ultraviolet B-narrowband (UV-B-NB) phototherapy. The patient subsequently had several relapses over 1 year, which were well controlled with short cycles of UV-B-NB. This patient's findings demonstrate that pustular eruptions can vary over time, assuming clearly different clinical patterns, and highlight the difficulty of classifying pustular eruptions as separate diseases.  相似文献   
110.
BACKGROUND: To perform lamellar keratolimbal allograft transplantation in a one-step procedure with a single graft, we investigated the feasibility of harvesting eccentric lamellar keratolimbal grafts from conventionally processed corneoscleral buttons using a manually guided microkeratome in conjunction with an artificial anterior chamber system. METHODS: We used the Moria LSK-One microkeratome and the automated lamellar therapeutic keratoplasty (ALTK) system (Antony, France). Ten human donor eyes were used to obtain single-piece lamellar keratolimbal grafts. Specimens were processed for light and electron microscopy. RESULTS: Eccentric keratolimbal grafts could be obtained from all human donor buttons. Grafts include a crescent-shaped limbal and a large corneal portion. No visible damage to the limbal region was discernible. CONCLUSION: Our data show that the LSK-One microkeratome in conjunction with the ALTK system allows harvesting eccentric keratolimbal grafts from donor corneoscleral buttons.  相似文献   
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