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1.
Background. A combined nevus most commonly consists of a blue nevus in combination with a Clark or Spitz nevus. Dermoscopically, combined nevus can mimic melanoma owing to the presence of dermoscopic features common to both types of lesions. Benign clinical and dermoscopic changes can occur in nevi over time, especially in children and young adults.
Objective. To describe the dermoscopic evolution of a congenital combined nevus showing unusual dermoscopic features.
Methods. Digital dermoscopic analysis was performed at the initial visit and after 8 months. The lesion was surgically excised and histopathologically examined.
Results. An asymptomatic plaque with a central blue area and peripheral brown pigmentation located on the back of a 13-year-old boy was diagnosed dermoscopically as combined nevus. Dermoscopic analysis 8 months later showed color changes from steel blue to gray-blue and black in the central area of the lesion, an increased number of blue-black dots or globules, and peripheral irregular streaks. Histopathology revealed typical features of a congenital combined nevus (blue nevus + compound nevus).
Conclusion. Over time, congenital combined nevus may show clinical and dermoscopic changes in size, color, and structure. Surgical excision is recommended when clinical and dermoscopic features are equivocal and the diagnosis of melanoma cannot be ruled out.
ANGELA FERRARI, MD, GIAN PIERO LOZZI, MD, MARIA CONCETTA FARGNOLI, MD, AND KETTY PERIS, MD, HAVE INDICATED NO SIGNIFICANT INTEREST WITH COMMERCIAL SUPPORTERS.  相似文献   
2.
Emiliano Sordi  MD    Angela Ferrari  MD    Domenico Piccolo  MD    Ketty Peris  MD 《Dermatologic surgery》2002,28(12):1182-1183
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3.
Several studies have been carried out to elucidate the causes of the low oral bioavailability of amoxicillin in rats. The hepatic first-pass effect of the antibiotic was estimated by comparing the area under the plasma drug concentration-versus-time curve from time zero to infinity (AUC0-infinity) obtained after injecting the drug into a mesenteric vein with the AUC0-infinity value obtained after injecting the drug into the jugular vein of conscious rats. No hepatic first-pass effect was detected. The bioavailability of amoxicillin after intraduodenal administration was only 51%, and the fraction of the dose remaining in the intestine at the end of the experiment was 4.5%. This was far less than the fraction that did not reach systemic circulation, which indicates a presystemic loss of drug, probably at the intestine. In vitro studies corroborated the fact that amoxicillin is subjected to presystemic degradation by intestinal juices and intestinal tissues. The greatest loss of drug occurred in the complete intestine (45% of the initial amount), and it was mainly due to the action of intestinal tissues (28% of the initial amount) but was also due to the action of intestinal juices (15% of the initial amount). The absorption of amoxicillin in three parts of the intestine (upper, middle, and lower) was also evaluated. The largest AUC0-infinity value and the highest plasma drug levels were obtained when amoxicillin absorption took place in the middle intestine. The smallest AUC0-infinity value and the lowest plasma drug levels corresponded to absorption from the upper intestine.  相似文献   
4.
Previous studies have shown that embryonic stem cells (ES) may participate in normal embryonic development when they are injected into the blastocyst. In contrast, ES cells develop into tumors if injected in ectopic sites in adult mice. In this study we injected ES-D3 cells, with the LacZ gene incorporated, into 5-day pregnant mouse uteri, into pregnant unilaterally salpingectomized uteri, into pseudo pregnant uteri and into non-pregnant uteri. X-gal staining enabled us to identify injected ES cells on the 7th, 9th, 10th, 12th and 15th days post-injection. In pregnant decidua, the ES cells were located initially in the mesometrial decidua and later distributed in the basal and capsular decidua and in the endodermic layer of the visceral yolk sac. In pregnant, unilaterally salpingectomized mouse uteri, ES cells were mainly located in the uterine lumen and tumors were not observed in either case. In contrast, ES cells injected into pseudopregnant uteri often developed into tumors and those injected into non-pregnant uteri always developed into teratocarcinomas. We conclude that the pregnant-uterine microenvironment may participate in the control of ES cell growth.  相似文献   
5.
The objective of the study was to describe the implementation of measures for preventing tobacco consumption developed in the Catalan Network of Smoke-free Hospitals. Information from 25 hospitals that are actively involved in the Catalan Network of Smoke-free Hospitals (April 2004) was used. The degree of implementation of the Smoke-free Hospitals Project was analysed by means of the Self-Audit Questionnaire of the European Network for Smoke-free Hospitals; each hospital was analysed globally and according to the duration of its Network membership (<1 year: implementation stage; > or =1 year: consolidation stage). In terms of global indicators, there were high levels of commitment (64.8%), communication (74.7%), tobacco control (77.4%) and implementation of smoke-free environments (81.0%). A lower degree of implementation (<50%) was found in education and training, health promotion and healthy workplaces. According to the duration of Network membership, significant differences were observed for communication, environment, healthy workplaces and follow-up. Deficits were observed in areas such as specialist training and cessation support, and further input is required here. By identifying areas needing attention, providing a guide for policy development and by administering it periodically, one can ensure that progress is kept on track.  相似文献   
6.
The melanocortin 1 receptor (MC1R) gene is a major determinant of human pigmentation and specific allelic variants have been associated with red hair and sun sensitive skin types as well as increased skin cancer risk in Caucasian individuals. We screened for allelic variants the entire MC1R coding region of 100 unrelated individuals sampled from an Italian population who has darker pigmentary traits than populations analyzed to date. Twenty MC1R variants were identified, eighteen located at non-synonymous sites and two at synonymous sites. We report four novel MC1R allelic variants: C35Y (g.104G>A), V38M (g.112G>A), L44V (g.130C>G) and I120T (g.359T>C).  相似文献   
7.
The pharmacokinetics and metabolism of 1H-indole-3-acetic acid, 1-(4-chlorobenzoyl)-5-methoxy-2-methyl 2-[4-[3-[[4-(benzoylamino)-5-(dipropylamino)-1, 5-dioxopentyl]oxy]propyl]-1-piperazinyl]ethyl ester (+/-) (proglumetacin, CR 604), 14C-labelled in position C-2 of the indolic moiety, was studied in male and female rats after oral administration. The radioactivity is slowly absorbed from the gastrointestinal tract and reaches the peak in plasma 6 h after administration. Afterwards the radioactivity is eliminated from plasma according to a bi-exponential equation, with an initial elimination rate having a t1/2 of 4.5 h and a terminal elimination rate having a t1/2 of 16 h. The elimination rate is probably dependent on the slow absorption rate (flip-flop system) and on an entero-hepatic recirculation of the radioactivity. The radioactivity is excreted with the feces (60.8%) and with the urines (33.5%). No radioactivity is eliminated with the expired air. About 13% of the fecal radioactivity is represented by proglumetacin. This fraction or radioactivity (ca. 8% of the administered) represents probably the non-absorbed amount of substance. The parent proglumetacin is not found in blood, urine and organs. Conversely several indolic metabolites are found, with a predomination of indometacin. Proglumetacin is therefore a pro-drug of indometacin and of other indolic metabolites, which are responsible for the antiinflammatory activity of proglumetacin. The radioactivity is distributed in all tissues. The maximum radioactivity is found in liver and kidneys, however, always in a smaller concentration than in plasma. No "deep compartment" was found.  相似文献   
8.
Serum tartrate-resistant acid phosphatase (TRAcP) activity is considered to be a biochemical marker of bone resorption. Recently, a lack of specificity of collagen-related markers for assessing bone turnover has been observed in patients with chronic liver disease. Thus, it could be of great interest to determine serum TRAcP activity in such patients. However, nonspecificity of the analytical reaction could occur when hemolyzed, lipemic, or icteric specimens are analyzed. Therefore, we have studied the interference caused by bilirubin in the measurement of serum TRAcP activity using the Hillmann method. The interference was assessed in two pools of serum containing different bilirubin concentrations but with similar total AcP levels. Mixing proportional parts of the two pools, 10 samples were also obtained. Serum activities of total AcP and TRAcP, and the concentration of bilirubin were measured in the 10 samples. Both the actual and the expected values obtained by theoretical calculations were compared. Serum bilirubin values of 2.4 mg/dl showed a negative interference of 15% in the determination of serum TRAcP activity, whereas values of bilirubin higher than 10 mg/dl interfered totally with the measurement of serum TRAcP. Bilirubin did not interfere with the total AcP determination. This study clearly shows the interference of bilirubin in the determination of serum TRAcP. This finding should be considered when bone metabolism disorders are evaluated in jaundiced patients. Received: 6 April 1998 / Accepted: 1 October 1998  相似文献   
9.
Childhood cancer mortality has sharply declined in most economically developed countries over the last years, whereas no substantial changes in the incidence have been observed. In Catalonia (Spain), childhood cancer mortality showed a considerable decline until 1992, but incidence trends have not been analysed in this population. To assess both recent incidence and mortality trends in this population, we analysed childhood (0-14 years) cancer data from the population-based Tarragona Cancer Registry and from the Mortality Registry of Catalonia (Spain) from 1980 to 1998. All cancer mortality decreased by -2.6% annually in boys (95% confidence interval, 95% CI -3.7, -1.6) and -3.7% in girls (95% CI -4.9, -2.5). Mortality due to leukaemia decreased annually -3.0% in boys (95% CI -4.7, -1.4) and -4.4% in girls (95% CI -6.3, -2.4). Mortality for brain tumours showed a reduction of -3.2% in boys (95% CI -5.5, -0.9) and of -4.4% in girls (95% CI -6.3, -2.4). No significant trend in incidence rates, either in boys or in girls, was observed (annual per cent of change for all cancers -0.5%, 95% CI -3.5, 2.7, in boys and 1.7%, 95% CI -1.9, 5.5, in girls). These results suggest an improvement in both childhood cancer diagnosis and treatment, which may explain current higher childhood cancer survival rates.  相似文献   
10.
This report describes a 56-year-old man with severe depression who developed bilateral foot drop, dual incontinence, and swallowing difficulties, which required several physical investigations and consultations before an excellent response to electroconvulsive therapy occurred with reversal of all symptoms.  相似文献   
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