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11.
Benzo[a]pyrene diol epoxide adducts with hemoglobin (Hb) weremeasured to detect human exposure to environmental benzo[a]pyrenefrom traffic exhaust. Benzo[a]pyrene tetrahydrotetrols (BPTs)released from Hb after acid hydrolysis were quantitated by gaschromatography-mass spectrometry after immunoaffinity chromatography.Fifty three newspaper vendors were enrolled. The median adductconcentration was 0.3 fmol BPTs/mg Hb in high density traffic-exposedvendors and  相似文献   
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The prevalence of primary headache (PH) in a multiple sclerosis (MS) sample vs. control healthy subjects was investigated at a neurological clinic in 2004–2005: 122 of 238 (51%) MS patients and 57 of 238 (23%) controls proved to be affected by headache. The groups did not differ for the rates of PH types. Headache types of MS patients were comparable to those of PH patients that were observed at the same institute in a case-control comparison. First symptoms of headache preceded those of MS in two thirds of cases. Headache features did not significantly change after MS onset. Comorbidity of MS and PH could be explained by some common clinical and biological traits.  相似文献   
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The epidemiological burden of diabetes mellitus is changing the classical model of diabetes management, in which a specialist center delivers care based on registration, recall and regular review. Primary care services are progressively assuming a crucial role in screening, prevention and management of the disease. It therefore becomes critical to improve the performance of primary care providers by suitable organizational interventions. The current advances in information technology (IT) and communications technology provide new ways for coping with organizational problems, and provide the opportunity to implement complex, multifaceted interventions in a cost-effective manner. Moreover, IT enables patients to exploit new modalities of access to healthcare services.This review highlights the current situation in the implementation and delivery of IT solutions for diabetes care, and describes the trends towards more advanced and innovative IT-based services.A large number of electronic patient records (EPRs), decision support tools and telemedicine solutions have been proposed and studied but a relatively low number of them have been fully exploited in clinical practice. The main reasons for this limited dissemination are related to the complexity of establishing and evaluating interventions that have a strong impact in the process of care. However, the need for a large scale reorganization of chronic care is now pushing towards the integration of the newest IT tools with new models of diabetes management.  相似文献   
15.
Contact diode laser myringotomy and mitomycin C in children   总被引:1,自引:0,他引:1  
OBJECTIVE: To investigate the use of contact diode laser myringotomy (C-LAM), combined with topical mitomycin C, as an alternative method for prolonged middle ear ventilation in children with otitis media with effusion. STUDY DESIGN AND SETTING: Prospective study at a tertiary care pediatric institution. METHODS: Fifteen children enrolled in the study. Mitomycin C was applied to the intact tympanic membrane in the right ears, whereas saline on the left side was used for controls. C-LAM was then performed in all ears. Outcome measures included healing rate and scarring, ear infection, and long-term audiometric follow-up. RESULTS: There was no significant difference in median healing rate. In each group, the median was between the third and fourth month. Normal hearing thresholds were obtained in all children at 2-year follow-up. CONCLUSION: C-LAM proved to be an effective method for medium-term ventilation, but topical mitomycin C before C-LAM did not prolong patency rate in our patients. No significant complication was encountered at 2-year follow-up.  相似文献   
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The urinary excretion of polyamines was evaluated before, during and after radiotherapy in 16 patients with advanced squamous cell carcinoma of the uterine cervix (stage IIb or IIIb) and in 7 cases with pelvic recurrence after surgery for various types of carcinoma. The concentration of spermidine was significantly higher in the patients with primary tumors than in those with recurrent tumors. After the first radiation fractions putrescine increased in the patients with primary tumors whereas it decreased in patients with recurrent tumors. The values tended to return to baseline levels with time following treatment initiation. Polyamine increased markedly during treatment in patients who remained disease-free for at least 5 years but not in the patients with progressive disease or relapse. The results suggest a different polyamine metabolism and a different response to radiotherapy of recurrent tumors compared to primary tumors. The increase of urinary polyamines, but not the baseline values, seemed to be correlated to the response after radiotherapy.  相似文献   
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The increased use of Ultrasonography (US) has led to increased detection of simple hepatic cysts. For symptomatic cysts treatment is necessary. Until some years ago surgery was the only therapy. We have treated a large number of patients with Percutaneous Alcohol Sclerotherapy (PAS) and evaluated retrospectively the efficacy of this approach.Data on 21 patients with symptomatic simple hepatic cysts were reviewed retrospectively. Cysts had a mean diameter of 9 cm (range: 7–15 cm). PAS was always performed under local anesthesia and US guidance. 25% of the volume was replaced with 95% ethanol and then completely aspirated after 20–30 minutes.No complications or deaths occurred. In all patients symptoms disappeared after treatment. In 15 out of 21 cases there was no evidence of residual cyst on US, computed tomography (CT) or magnetic resonance (MRI). In 6 patients with shorter follow-up, cysts showed a mean reduction in diameter of 50%. The mean follow-up was 18 months (range 6–60 months).We conclude that PAS is easy with low risk for the patients and with good long-term results; it should therefore become the procedure of choice for simple hepatic cysts.  相似文献   
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The existence of a dose-related increase of lung cancer riskin cigarette smokers has been indisputably established. Thisfinding, however, is not confirmed at low doses (< 5 cigarettes/day),there still being a lack of epidemiological data. The use ofmathematical models of carcinogenesis to extrapolate from higherdoses allows estimation of the risk for very light smokers.The present study has been designed to compare a set of mathematicalmodels, i.e. one-hit, two-stage, multi-stage, logit, probit,and Weibull, in extrapolating relative risks at low doses fromthe data of nine large cohort studies on cigarette smokers reportedin the IARC Scientific Monograph on tobacco smoking. All modelsevaluated, apart from the one-hit, achieved a good fit, withthe proportion of explained variance ranging between 61% and67%. The relative risk estimates for passive smokers from themost updated epidemiological studies were taken into accountto evaluate, on the basis of these models, the correspondingexposure in terms of ‘cigarette equivalent’ smoked.These values ranged from 0.21 to 0.43 cigarettes/day for thetwo-stage and multistage model, while probit, logit and Weibullmodels, yielded estimates one or even two orders of magnitudelower. The authors emphasize the substantial agreement betweenthe estimates of ‘cigarette equivalent9 based on the applicationof two-stage and multi-stage models to the epidemiological evidenceon the effect of passive smoking and to the data based on thecomparison of tobacco metabolites in active and passive smokers.  相似文献   
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