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51.
BACKGROUND: Tobacco smoking is one of the main risk factors for oral, pharyngeal and oesophageal cancers in developed countries. Information on the role of the tar yield of cigarettes in upper digestive tract carcinogenesis is sparse and needs to be updated because the tar yield of cigarettes has steadily decreased over the last few decades. PATIENTS AND METHODS: We analysed two case-control studies, from Italy and Switzerland, conducted between 1992 and 1999, involving 749 cases of oral and pharyngeal cancer and 1770 controls, and 395 cases of squamous-cell oesophageal carcinoma and 1066 matched controls. Odds ratios (ORs) were estimated by unconditional multiple logistic regression models, including terms for age, sex, study centre, education and alcohol consumption. RESULTS: Based on the brand of cigarettes smoked for the longest time, the multivariate ORs for current smokers compared with never smokers were 6.1 for <20 mg and 9.8 for >or=20 mg tar for oral and pharyngeal neoplasms, and 4.8 and 5.4 for oesophageal cancer, respectively. For the cigarette brand smoked in the previous six months, the ORs for >or=10 mg compared with <10 mg were 1.9 for cancer of the oral cavity and pharynx and 1.8 for oesophageal cancer, after allowance for number of cigarettes and duration of smoking. CONCLUSIONS: The present study confirms the direct relationship between the tar yield of cigarettes and upper digestive tract neoplasms, and provides innovative information on lower tar cigarettes, which imply reduced risks compared with higher tar ones. However, significant excess risks were observed even in the lower tar category, thus giving unequivocal indications for stopping smoking as a priority for prevention of upper digestive tract neoplasms.  相似文献   
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AIMS: To define outcome measures for auditing the clinical care of children and adolescents with insulin dependent diabetes mellitus (IDDM) and to assess the benefit of appointing a dedicated paediatric trained diabetes specialist nurse (PDSN). METHODS: Retrospective analysis of medical notes and hospital records. Glycaemic control, growth, weight gain, microvascular complications, school absence, and the proportion of children undergoing an annual clinical review and diabetes education session were assessed. The effect of the appointment of a PDSN on the frequency of hospital admission, length of inpatient stay, and outpatient attendance was evaluated. RESULTS: Children with IDDM were of normal height and grew well for three years after diagnosis, but grew suboptimally thereafter. Weight gain was above average every year after diagnosis. Glycaemic control was poor at all ages with only 16% of children having an acceptable glycated haemoglobin. Eighty five per cent of patients underwent a formal annual clinical review, of whom 16% had background retinopathy and 20% microalbuminuria in one or more samples. After appointing the PDSN the median length of hospital stay for newly diagnosed patients decreased from five days to one day, with 10 of 24 children not admitted. None of the latter was admitted during the next year. There was no evidence of the PDSN affecting the frequency of readmission or length of stay of children with established IDDM. Non-attendance at the outpatient clinic was reduced from a median of 19 to 10%. CONCLUSIONS: Outcome measures for evaluating the care of children with IDDM can be defined and evaluated. Specialist nursing support markedly reduces the length of hospital stay of newly diagnosed patients without sacrificing the quality of care.  相似文献   
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This report highlights the association between tuberous sclerosis and Wolff-Parkinson-White syndrome. Ten patients with concurrent diagnoses of Wolff-Parkinson-White syndrome and tuberous sclerosis were identified. Wolff-Parkinson-White syndrome presented early in life, nine cases being diagnosed in the first year. Eight of the 10 cases were male. In eight cases, the syndrome was associated with supraventricular tachycardias, and in nine with cardiac rhabdomyomata. One child died from cardiac failure secondary to obstruction of the left ventricular outflow tract by a rhabdomyoma. Five of nine survivors showed resolution of Wolff-Parkinson-White syndrome on follow up. The accessory pathway was localised in nine patients from surface electrocardiograms: six children had left sided pathways and three had right sided pathways.  相似文献   
54.
In this study we have analyzed the vascular response induced in the two- stage carcinogenesis model in SENCAR mice. The role of angiogenesis has not been explored in this model, which is the paradigm of multistage carcinogenesis and a model for neoplastic lesions derived from exophytic premalignant lesions (e.g. colon carcinoma, bladder papilloma). We investigated if angiogenesis is involved in the formation of papillomas and in the progression from papilloma to carcinoma. To this end we analyzed the vasculature of normal and hyperplastic skin, focal epidermal hyperplasias that are precursors of papillomas, papillomas at different stages and squamous cell carcinomas. We also analyzed the vascularization of papillomas induced in two strains of mice that differ in their susceptibility to malignant progression. We show here that angiogenesis is turned on in the earliest stages of papilloma formation. In late stages, regardless of state of progression, the predominant response is an increase in the size of blood vessels. Thus, in the SENCAR mouse model, representative of exophytic tumors, the angiogenesis switch is a very early event, probably mechanistically related to the development of the primarily exophytic lesions. Therefore, the density of blood vessels cannot be used as a predictor of malignant progression in this model.   相似文献   
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AIM: Morbid obesity has increased its frequency in the last 20 years in association with the increase of a country's richness. Bariatric surgery has developed a role which is becoming more and more important. The aim of this study, after 10 years of experience with the biliopancreatic diversion, is to compare the laparoscopic versus open technique RESULTS: METHODS: From March 1993 to December 2004, 150 patients were operated by biliopancreatic diversion. We divided our experience into 2 groups: laparotomic and laparoscopic techniques. We compared the following variables in the 2 groups: total operating time, intestinal functions, postoperative pain, patient's discharge and recovery time, major postoperative complications, postoperative mortality, late complications, incisional hernia incidence and anastomotic ulceration. RESULTS: We found a significant difference in both the reduction of the postoperative pain and the recanalization time in the laparoscopic group. Equally, we found a reduction in the incidence of abdominal wall complications, especially the reduction of incisional hernia and infections. The mean operative time was longer in the laparoscopic group, in particular due to the hard learning curve. CONCLUSIONS: The laparoscopic biliopancreatic diversion is a feasible and safe operation with good results: less postoperative discomfort, shorter recanalization and ospedalization time, less incidence of abdominal wall morbidity (incisional hernia). However, the procedure may prove difficult and it needs a highly experienced surgeon in laparoscopic technique.  相似文献   
60.
Risk factors for definite hypertension were examined using data from two Italian rural cohorts from the Seven Countries Study, originally composed of 1,712 men ages 40-59 at entry. Two approaches were used: cross-sectional examination of baseline exposure/outcome measurements; and prospective examination of data, correlating baseline measurements with subsequent definite hypertension, diagnosed at the 10-year follow-up exam. Hypertension was defined as diastolic blood pressure greater than or equal to 95 mm Hg or systolic blood pressure greater than or equal to 160 mm Hg. Included in the cross-sectional analysis were 1,437 subjects free from other cardiovascular diseases at baseline. Of these, 590 were included in the prospective analysis. Using a multiple logistic function that did not include baseline (normal) blood pressure, age, pulse rate, and weight were confirmed as risk factors for hypertension both cross-sectionally and prospectively, thus suggesting that bias cannot explain the relationship of hypertension to these factors. Although proteinuria and vital capacity were associated with hypertension in the cross-sectional analysis, no such relationships were detected prospectively, thus implying that these factors are effects, rather than determinants, of definite hypertension. Smoking had a negative prospective (but not cross-sectional) association with hypertension, which can probably be explained by survival bias at 10 years after ascertainment of smoking habits. When mean baseline blood pressure was added to the prospective multiple logistic function, it became the only factor significantly associated with hypertension (P less than 0.001), again confirming the importance of "tracking" in the determination of hypertension.  相似文献   
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