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1.
BACKGROUND: Development of more than one primary melanoma in a patient is a relatively uncommon but well-recognized phenomenon. Its frequency has ranged from 1.2% to 8.2% in several series. This subgroup of patients with multiple primary lesions has not been characterized sufficiently. We report the experience of the Melanoma Unit of University Hospital Spedali Civili of Brescia, Italy. METHOD: Study subjects were drawn from 1240 patients with histologically confirmed melanoma, including melanoma in situ. From this group, multiple melanomas developed in 47 patients (3.79%). Every one of our patients has been taught to perform self-examination of the skin to detect suspicious pigmented lesions. RESULTS: Of the 47 patients described in this study, 38 had two primary melanomas, 7 had three melanomas and 2 had 5 and 10 melanomas, respectively. Mean age at first diagnosis was 46.2 years. The majority of subsequent melanomas (74.5%) were removed within 5 years of the initial operation. Synchronous lesions were found in 10 patients. In male patients, the lesion appeared most frequently on the trunk; in female patients, melanoma appeared mostly on the lower extremities. The second primary melanomas developed in the same anatomic region from the first in 53.2% of our patients. The proportion of in situ to invasive melanomas was greater for the second melanomas compared with the first melanomas. Regarding invasive melanomas, the mean thickness of the first melanomas was 1.31 mm compared with 0.66 mm for the second ones. Dividing patients into two groups, of more and less than 50, it is highlighted that in older patients synchronous lesions appear more frequently (36.4% vs. 8.0%); the median time interval between sequential melanomas is longer (84 vs. 63.7 months); and the ratio between the primary and secondary melanoma mean thickness is lower (1.21 : 1.08 vs. 1.43 : 0.63 mm). CONCLUSIONS: The study confirms that second primary melanoma is usually thinner than the first lesion, and it is more common in the same region of the body as the initial melanoma. The highest risk for a second melanoma is during the first 5 years, but a much longer time interval of 28 years is possible. Continued medical follow-up with complete skin examinations seems prudent, but it is very important to promote self-skin evaluation in patients to detect not only metastases but also subsequent primary melanomas in their earliest phases.  相似文献   
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The Toronto Sexual Contact Study comprises a cohort of 249 male sexual contacts of men with HIV disease which has been followed every 3 months for almost 5 years. On enrollment 143 were seropositive and 16 seroconverted during the follow-up period. By 31 December 1989, 41 of the 159 seropositive cohort members had developed AIDS. Using Cox relative risk regression models, we investigated the association of a number of laboratory and clinical variables and progression to AIDS. Fixed covariate models examined laboratory variables from the enrollment visit of cohort members, with time calculated from this date. In models assessing time dependent covariates, time was calculated from the estimated date of HIV infection. In the univariate models of either fixed or time dependent covariates, many variables were significantly associated with risk of progression to AIDS (T4 cell count, T4/T8 ratio, blastogenic responses to phytohemagglutinin, concanavalin A, and pokeweed mitogen, serum IgA, appearance of p24 antigen, and the development of oral hairy leukoplakia, thrush, or herpes zoster). Appearance of persistent generalized lymphadenopathy was not associated with increased risk of progression. In the multivariate model which evaluated fixed laboratory covariates, T4/T8 ratio, IgA level, and PHA response at enrollment were significantly associated with elevated risk.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
4.
Respiratory syncytial virus (RSV) bronchiolitis is a very common infection in infants and, after the acute phase, a number of patients develop a reactive airway disease that lasts for years. Although the pathogenesis of the lung damage after RSV bronchiolitis is still largely unknown, previous studies suggest that leukotrienes may play an active part in it. The aim of this study was to measure leukotriene levels in the nasal lavage fluid (NLF) collected in infants during RSV bronchiolitis and 1 month later. Cysteinyl leukotrienes (Cys-LTs) and leukotriene B(4) (LTB(4)) were measured in the NLF of 22 infants with their first episode of RSV bronchiolitis and 16 healthy infants. A second NLF sample was collected to measure leukotriene levels 1 month after the acute disease. NLF Cys-LT levels were significantly higher in infants with RSV bronchiolitis than in healthy controls [950 pg/ml (285.5-2155.9) vs. 110.5 pg/ml (66.5-451.3), p = 0.01], and they remained so a month after the acute infection (p = 0.02). A subanalysis showed no difference in Cys-LTs concentrations, either between bronchiolitis infants with and without a family history of atopy, or between those with and without passive exposure to cigarette smoke. No significant difference was found between the LTB(4) levels measured in the bronchiolitis cases and the control children. Cys-LTs are significantly increased in the NLF of infants with acute RSV bronchiolitis, and remain so at 1-month follow-up, suggesting a possible role of these eicosanoids in the pathogenesis of the disease.  相似文献   
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6.

Introduction

Pre-operative donation of autologous blood is a practice that is now being abandoned. Alternative methods of transfusing autologous blood, other than predeposited blood, do however play a role in limiting the need for transfusion of allogeneic blood. This survey of autologous blood transfusion practices, promoted by the Italian Society of Transfusion Medicine and Immunohaematology more than 2 years after the publication of national recommendations on the subject, was intended to acquire information on the indications for predeposit in Italy and on some organisational aspects of the alternative techniques of autotransfusion.

Materials and methods

A structured questionnaire consisting of 22 questions on the indications and organisational methods of autologous blood transfusion was made available on a web platform from 15 January to 15 March, 2013. The 232 Transfusion Services in Italy were invited by e-mail to complete the online survey.

Results

Of the 232 transfusion structures contacted, 160 (69%) responded to the survey, with the response rate decreasing from the North towards the South and the Islands. The use of predeposit has decreased considerably in Italy and about 50% of the units collected are discarded because of lack of use. Alternative techniques (acute isovolaemic haemodilution and peri-operative blood salvage) are used at different frequencies across the country.

Discussion

The data collected in this survey can be considered representative of national practice; they show that the already very limited indications for predeposit autologous blood transfusion must be adhered to even more scrupulously, also to avoid the notable waste of resources due to unused units.Users of alternative autotransfusion techniques must be involved in order to gain a full picture of the degree of use of such techniques; multidisciplinary agreement on the indications for their use is essential in order for these indications to have an effective role in “patient blood management” programmes.  相似文献   
7.
We investigated the hypothesis that gay and bisexual men experiencing stressful life events are more likely to engage in risky sexual behavior. Data were from a cohort study of 155 HIV-positive and 207 HIV-negative men in Ontario, Canada (1998–2007). We quantified the relation between stressful life events and unprotected anal intercourse with a non-regular partner. In the past 6 months, 19% reported unprotected intercourse (HIV+: 28%; HIV−: 13%) and 58% reported one or more stressful life events (HIV+: 64%; HIV−: 55%). Among HIV-negative men, the odds of unprotected intercourse increased by 1.15 for each additional event (95%CI 1.06, 1.24). Among HIV-positive men, those who reported the event “problems due to alcohol or drugs” were 1.80 (95%CI 1.27, 2.56) times more likely to report unprotected intercourse. Interventions to assist men to cope with stress may help to prevent population spread of HIV and improve overall health.  相似文献   
8.
Prevalence and possible mechanisms of ventricular arrhythmias in athletes   总被引:1,自引:0,他引:1  
To investigate the prevalence and nature of ventricular arrhythmias in athletes, 40 well trained healthy endurance athletes (20 cyclists and 20 runners) and 40 healthy sedentary subjects as controls were studied. Twenty four-hour continuous ECG monitoring showed a higher, even though not significant prevalence of ventricular ectopy in athletes (70% vs 55%). Complex forms of ventricular ectopy were also more prevalent in the athletes than in the controls (25% vs 5%; p less than 0.05). A prolongation of both measured QT interval and QT corrected for heart rate was observed at the ECG. Echocardiograms showed higher dimensional indices in the athletes, while functional indices were similar in athletes and controls. No correlation was found between any ECG or echocardiographic finding and the grade of ventricular arrhythmia. The comparison between the cyclists and the runners did not show any significant difference in the prevalence of ventricular arrhythmias or in the QT interval duration.  相似文献   
9.

Objective

A handheld device using near-infrared technology (Infrascanner) has shown good accuracy for detection of traumatic intracranial haemorrhages in adults. This study aims to determine the feasibility of use of Infrascanner in children with minor head injury (MHI) in the Emergency Department (ED). Secondary aim was to assess its potential usefulness to reduce CT scan rate.

Methods

Prospective pilot study conducted in two paediatric EDs, including children at high or intermediate risk for clinically important traumatic brain injury (ciTBI) according to the adapted PECARN rule in use. Completion of Infrascanner measurements and time to completion were recorded. Decision on CT scan and CT scan reporting were performed independently and blinded to Infrascanner results.

Results

Completion of the Infrascanner measurement was successfully achieved in 103 (94 %) of 110 patients enrolled, after a mean of 4.4?±?2.9 min. A CT scan was performed in 18 (17.5 %) children. Only one had an intracranial haemorrhage that was correctly identified by the Infrascanner. The exploratory analysis showed a specificity of 93 % (95 % CI, 86.5–96.6) and a negative predictive value of 100 % (95 % CI, 81.6–100) for ciTBI. The use of Infrascanner would have led to avoid ten CT scan, reducing the CT scan rate by 58.8 %.

Conclusions

Infrascanner seems an easy-to-use tool for children presenting to the ED following a MHI, given the high completion rate and short time to completion. Our preliminary results suggest that Infrascanner is worthy of further investigation as a potential tool to decrease the CT scan rate in children with MHI.  相似文献   
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