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991.
Seidenari Stefania MD Pellacani Giovanni MD Martella Alessandro MD 《Dermatologic surgery》2005,31(2):184-189
BACKGROUND: Because melanoma may sometimes be difficult to differentiate from nevi with clinical atypia, many benign lesions also undergo surgical removal. OBJECTIVE: To assess color type and distribution in dermoscopic melanocytic lesion images and to analyze the influence of color parameters on the diagnostic process and the decision to excise. METHODS: Overall, 603 images, referring to 112 melanomas and 491 nevi, were retrospectively subdivided into four groups: "clearly benign," "follow-up," "dermoscopic atypical nevi," and "dermoscopic melanomas," according to their dermoscopic aspects. The frequency of color type, number, and asymmetry were evaluated on digital images. RESULTS: With respect to lesions not eligible for excision according to dermoscopy (but excised for cosmetic reasons), those excised with a suspicion of malignancy showed a higher number of colors, whose distribution was also more asymmetric. Moreover, the frequency of the presence of black and blue-gray progressively increased from clearly benign lesions to atypical nevi and dermoscopic melanomas. CONCLUSION: In dermoscopic images, color parameters are essential elements for the diagnosis of atypical nevus, which can be differentiated from both a clearly benign lesion and a melanoma. Furthermore, pigmentation asymmetry and the presence of blue-gray represent the main color features, which should lead to the decision to excise. 相似文献
992.
Adrenal incidentaloma: the influence of a decision-making algorithm on the short-term outcome of laparoscopy 总被引:1,自引:0,他引:1
Valeri A Bergamini C Manca G Mannelli M Presenti L Peri A Borrelli A Tonelli P 《Journal of laparoendoscopic & advanced surgical techniques. Part A》2005,15(5):451-459
BACKGROUND: At the present time, the precise indications for laparoscopic surgery of adrenal incidentaloma (AI) have yet to be completely clarified. The most controversial issue is the role of laparoscopy in the treatment of potentially malignant and large adrenal masses. Trying to address these questions, we retrospectively examined a group of patients with AIs. MATERIALS AND METHODS: Forty-two patients with AIs who were laparoscopically treated since 1995 were enrolled in this study. The patients were divided into two groups: the 27 patients of the immediate surgery (IS) group were operated on immediately, whereas the 15 subjects in the delayed surgery (DS) group needed further evaluations and/or a follow-up period before surgery. Surgical timing for both groups was decided according to a widely accepted decision-making algorithm. Many outcome parameters of laparoscopy (operative time, blood loss, conversion rate, time to liquid and solid food nutrition, drainage removal, resumption of normal bowel habits, and average hospital stay) were analyzed in the two groups. The subjects had AIs of various sizes and different histotypes. RESULTS: Patients in the DS group had a higher risk for malignancy. The definitive pathology revealed a malignant biology in 26.6% of DS vs. 0% of IS cases. No difference in the outcome parameters of laparoscopy was observed between the two groups or among pathologically different AIs. A significant correlation was found between the operative time and the size of the AI (r=0.836, P<0.001, linear regression test). CONCLUSION: Our study shows that laparoscopy is feasible and safe for AIs, regardless of the preoperative probability of malignancy. The size of the AI was the only determinant for choosing a laparotomy. Further long-term studies are necessary to confirm the laparoscopic efficacy in terms of oncologic safety. 相似文献
993.
Peruzzi L Lombardo F Amore A Merlini E Restagno G Silvestro L Papalia T Coppo R 《The Journal of urology》2005,174(2):713-717
PURPOSE: Obstructive uropathies, including posterior urethral valves (PUVs) and kidney hypodysplasia, are the most frequent cause of renal failure in children. The role of renin-angiotensin system genes in renal and urinary tract development has been observed in experimental models. The aim of this study was to investigate the distribution of angiotensin converting enzyme (ACE), angiotensinogen (AGT) and angiotensin receptor type 1 (ATR1) genetic polymorphisms in children affected by chronic renal failure due to renal hypodysplasia associated with posterior urethral valves or without urethral abnormalities. MATERIALS AND METHODS: The study included 50 children (21 with hypodysplasia associated with PUVs, 7 with obstructive uropathy and 22 with pure hypodysplasia) and 50 healthy subjects matched for sex and geographic origin. ACE ID, AGT TC and ATR1 AC gene polymorphisms were assayed in all patients with standard polymerase chain reaction techniques. RESULTS: ACE II was expressed more in patients with PUVs compared to those with other dysplasias and controls (43% vs 7% and 10%, respectively, chi-square test p <0.05), while ATR1 AA was significantly less represented in patients with hypodysplasia compared to controls (38% vs 56%, chi-square test p <0.05). ACE DD and AGT genotypes were not distributed differently in patients with PUVs compared to those with other dysplasias and controls. CONCLUSIONS: To our knowledge this is the first report associating severe congenital uropathies and renal hypodysplasia with decreased renin-angiotensin system activity associated with the ACE II genotype and a possible functional imbalance among ATR1 receptors. 相似文献
994.
Cotrufo M Della Corte A De Santo LS Quarto C De Feo M Romano G Amarelli C Scardone M Di Meglio F Guerra G Scarano M Vitale S Castaldo C Montagnani S 《The Journal of thoracic and cardiovascular surgery》2005,130(2):504-511
OBJECTIVE: This study aimed to assess extracellular matrix protein expression patterns at the convexity (right anterolateral wall) and the concavity of the dilated ascending aorta in patients with bicuspid aortic valve disease. METHODS: Aortic wall specimens were retrieved from the convexity and the concavity in 27 bicuspid aortic valve patients (12 with stenosis and 15 with regurgitation) and 6 heart donors (controls). Morphometry, immunohistochemistry, Western blot, and polymerase chain reaction were performed, focusing on matrix proteins involved in vascular remodeling. RESULTS: Type I and III collagens were significantly decreased in bicuspid-associated dilated aortas versus controls (P < .001), particularly at the convexity (P < .05 vs concavity). Expression of messenger RNA for collagens was lower than normal only in the regurgitant subgroup. At immunohistochemistry, proteins whose overproduction has been demonstrated in response to abnormal wall stress, such as tenascin and fibronectin, were more expressed in the convexity than in the concavity, especially in the stenosis subgroup. Tenascin, which is produced by smooth muscle cells in the synthetic phenotype, was nearly undetectable in controls. Fewer smooth muscle cells (stenosis, P = .017; regurgitation, P = .008) and more severe elastic fiber fragmentation (P = .029 and P < .001) were observed in the convexity versus the concavity. CONCLUSIONS: In bicuspid-associated aortic dilations, an asymmetric pattern of matrix protein expression was found that was consistent with the asymmetry in wall-stress distribution reported previously. Differences exist between patients with stenosis and those with regurgitation in terms of protein expression and content in the aortic wall. Further studies could clarify the relations between these findings and the pathogenesis of aortic dilatation in bicuspid aortic valve patients. 相似文献
995.
Menotti A Lanti M Kromhout D Kafatos A Nedeljkovic S Nissinen A 《European journal of epidemiology》2005,20(7):597-604
Aims: The purpose was to study the association of a single serum cholesterol measurement with early and late coronary and other cardiovascular deaths during 35 years of follow-up in samples of men aged 40–59 years in five European countries. Methods and results: A single serum total cholesterol measurement was considered in samples from Finland (N = 1563), the Netherlands (N = 811), Italy (N = 1642), Serbia (N = 1537) and Greece (N = 1158) (total = 6711). Seven partitioned proportional hazards models were solved, one for each of seven independent 5-year blocks, to predict coronary, stroke, cardiovascular disease and all-cause mortality risk. Partitioned hazard scores were cumulated. The resulting curves showed a relatively constant strength in risk for coronary deaths as a function of baseline serum cholesterol levels, although a strong relationship during the first 10-year period was followed by a weaker relationship later on. The pooled estimates for the five countries gave a relative risk for 1 mmol/l of serum cholesterol (95% confidence intervals) of 1.44 (1.23–1.68) for the first period; 1.52 (1.31–1.76) for the second period; and 1.16 (1.02–1.32) for the third period; 1.18 (1.05–1.32) for the forth period; 1.17 (1.05–1.31) for the fifth period; 1.22 (1.10–1.35) for the sixth period; 1.18 (1.05–1.32) for the seventh 5-year period of follow-up. No significant relationship were found between serum cholesterol and stroke and all-cause mortality, while intermediate findings were obtained for cardiovascular diseases. Conclusion: A single serum cholesterol measurement in middle aged-men maintains a strong relationship with the occurrence of coronary heart disease (CHD) deaths during 35 years of follow-up. 相似文献
996.
Iavicoli I Marinaccio A Carelli G 《Journal of occupational and environmental medicine / American College of Occupational and Environmental Medicine》2005,47(5):453-457
OBJECTIVE: We sought to investigate trichloroethylene-induced alterations of the immune system in humans. METHODS: The levels of interleukin-2, interleukin-4, and interferon-gamma in sera obtained from workers exposed to trichloroethylene were determined and compared with those of internal and external control subjects. RESULTS: In workers with a mean urinary trichloroacetic acid concentration of 13.3 +/- 5.9 mg/g creatinine, exposed to a mean environmental trichloroethylene level of 35 +/- 14 mg/m, we observed a significant increase in sera interleukin-2 and interferon-gamma levels and a reduction in interleukin-4 concentrations compared with those of workers from the internal and external control groups. CONCLUSIONS: This study provides the first report on quantitative immune changes induced by occupational exposure to low levels of trichloroethylene and strongly suggests that exposure to this substance alters immunohomeostasis in humans with possible effects on health. 相似文献
997.
Missori P Ramieri A Costanzo G Peschillo S Paolini S Miscusi M D'Andrea G Delfini R 《Journal of neurosurgery. Spine》2005,3(1):57-60
Late-onset vertebral body (VB) fracture after lumbar transpedicular fixation has not been previously described in the literature. The authors present three cases in which VB fracture occurred several months after posterolateral fixation in patients with degenerative disease or traumatic injury. The authors suggest that postoperative osteopenia, modified load-sharing function, and intravertebral clefts were responsible for the fractures. Two women and one man were evaluated at a mean follow-up interval of 3 months. Two patients suffered recurrent lumbar pain. Radiography and magnetic resonance imaging revealed fracture of some of the instrumentation-treated VBs. These two patients underwent surgical superior or inferior extension of instrumentation. The third, an asymptomatic patient, received conservative management. The two patients who underwent reoperation made complete recoveries, and there was no evidence of further bone collapse in any case. The authors speculate that alterations in the VBs may occur following application of spinal instrumentation. In rare cases, the device can fracture and consequently lead to recurrent lumbar back pain. Recovery can be achieved by extending the instrumentation in the appropriate direction. 相似文献
998.
The incidence of renal cell carcinoma is increasing, in part due to the growing use of cross-sectional imaging. Most renal tumors are now incidentally detected as small masses in asymptomatic patients. A minority of small renal masses, presumed to be renal cell carcinoma, grow significantly over time if managed conservatively, but the growth rate of the majority is slow or undetectable. In the absence of other prognostic factors, measurement of tumor growth rate can be helpful for initial conservative management of selected patients with small renal tumors. To date, there have been no reports of progression to metastatic disease occurring during active surveillance, but longer follow-up is needed to confirm this observation. The standard of care for small localized renal neoplasms is partial or radical nephrectomy. At the present time, active surveillance of small renal masses, with delayed therapy for patients whose disease progresses, is an experimental approach that can be considered for the elderly or patients with significant comorbidity. Renal core biopsy and fine-needle aspiration can provide essential information for treatment decision-making and should therefore be considered in the diagnostic work-up of all small renal masses. In future, the identification of prognostic indicators, with the use of new techniques including functional imaging and molecular or genomic characterization of tissue from needle biopsies, are expected to help clinicians differentiate between indolent and potentially aggressive small renal tumors. 相似文献
999.
Portaluri M Casciaro S Bambace S Tramacere F Casciaro E Recchia V Sanzo A Pili G Didonna V Distante A 《Annali dell'Istituto superiore di sanità》2005,41(4):493-499
A checking form was introduced in order to test the completeness of electronic and paper patient's charts in a radiotherapy department which had introduced record-and-verify system (RVS) and to improve tha staff performance. The chosen items for the electronic chart were 9 and 5 for paper chart. 223 patients were reviewed in two phases. The data analysis was based on a scoring method, attributing a positive score (+1) to the operator's good behaviour, a negative score (-1) to the lack of data input and a neutral score (0) to the inapplicable situation. The average global score increased from 0.4 to 0.7: in A (lowest complexity) category from 0.37 to 0.64, in B category from 0.4 to 0.89, in C category from 0.48 to 0.61. 相似文献
1000.
Visconti A Cotichini R Cannoni S Bocca B Forte G Ghazaryan A Santucci S D'Ippolito C Stazi MA Salvetti M Alimonti A Ristori G 《Annali dell'Istituto superiore di sanità》2005,41(2):217-222
Twenty-six chemical elements and oxidative status were determined in serum of 12 patients with first demyelinating episode and brain magnetic resonance imaging compatible with the disease at different time points. Quantifications of Al, Ba, Be, Bi, Ca, Cd, Co, Cr, Cu, Fe, Hg, Li, Mg, Mn, Mo, Ni, Pb, Sb, Si, Sn, Sr, V, Tl, W, Zn and Zr, as well as of serum oxidative status and antioxidant capacity were carried out. The results were compared with values obtained from healthy subjects living in the same geographic area. Concentration variability, expressed as coefficient of variation (CV), was evaluated over a six months longitudinal follow-up. The CV was higher for Li and Pb, while showed minimal variation for Ca, Cu, Mg and Zn--elements strictly body regulated. Significant difference (p < or = 0.05) in mean concentrations of Ba, Ca, Cd, Cr, Li, Mn, Mo, Ni, Sb, Si, Sn and Zr between patients at time 0 and controls was also found. 相似文献