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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   
3.
Over a 6-year period (1982 to 1988), 36 episodes of septic arthritis were diagnosed in 35 heroin addicts from Barcelona, Spain. Thirty (86%) were men and five (14%) were women, with a mean age of 24 years (range, 14 to 39). Twenty-nine episodes (80%) were monoarticular and seven (20%) were oligoarticular. The sacroiliac (16 cases), sternoclavicular (8), hip (5), and shoulder (4) joints were most frequently infected. Staphylococcus aureus and Pseudomonas aeruginosa were the etiological agents in 75% and 11% of episodes, respectively. Response to antibiotic treatment was good in 32 cases (90%), eight patients needed surgical drainage, and none died. We conclude that septic arthritis in heroin addicts localizes predominantly in axial joints. In our geographic area, infection with S aureus is more frequent than with gram-negative rods such as P aeruginosa or Serratia marcescens, which are most frequently found in reports from the United States.  相似文献   
4.
Emiliano Sordi  MD    Angela Ferrari  MD    Domenico Piccolo  MD    Ketty Peris  MD 《Dermatologic surgery》2002,28(12):1182-1183
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5.
Moderate increases in ``classical' biochemical markers of bone turnover have been described only in some patients with Camurati–Engelmann disease. However, the determination of the following ``new' markers has not been previously performed: serum osteocalcin (BGP), bone alkaline phosphatase (BAP), carboxyterminal propeptide of type I procollagen (PICP), aminoterminal propeptide of type I procollagen (PINP), tartrate-resistant acid phosphatase (TRAP), telopeptide carboxyterminal of type I collagen (ICTP), urinary pyridinoline (PYR), crosslinked N-telopeptides of type I collagen (NTX), and Crosslaps (CL). Such a determination may improve the evaluation of the disease activity. To evaluate the usefulness of biochemical markers of bone turnover reflecting Camurati–Engelmann disease activity we measured the levels of all these markers in four affected patients. The results were compared with bone scintigraphic indices of disease activity. Except for PICP and TRAP, bone formation and resorption markers were abnormal in all patients and were related to bone scan indices of disease activity. Among the markers of bone formation PINP, BAP, and BGP showed the highest values, whereas NTX and CL were the most sensitive markers of bone resorption. These results suggest that the determination of NTX or CL, and PINP or either BAP and BGP, associated with bone scan evaluation, provides the best assessment of Camurati–Engelmann disease activity. Received: 14 June 1996 / Accepted: 31 December 1996  相似文献   
6.
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   
7.
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   
8.
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   
9.
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   
10.
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   
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