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41.
Several studies in the past have shown appreciably higher lung cancer risk estimates associated with smoking exposure among men than among women, while more recent studies in the USA report just the opposite. To evaluate this topic in a European population we conducted a case-control study of lung cancer in three German and three Italian centres. Personal interviews and standardized questionnaires were used to obtain detailed life-long smoking and occupational histories from 3723 male and 900 female cases and 4075 male and 1094 female controls. Lung cancer risk comparing ever-smokers with never-smokers was higher among men (odds ratios (OR) adjusted for age and centre = 16.1, 95% confidence interval (CI) 12.8-20.3) than among women (OR = 4.2, CI 3.5-5.1). Because the smoking habits of women were different from men, we conducted more detailed analyses using comparable levels of smoking exposure. After restriction to smokers and adjustment for other smoking variables, risk estimates did not differ appreciably between genders. The analysis of duration of smoking (0-19, 20-39, 40+ years) adjusted for cigarette consumption and time since quitting smoking revealed similar risk estimates in men (OR = 1.0, 3.3 [CI 2.6-4.2], 4.1 [CI 3.1-5.6]) and women (OR = 1.0, 2.7 [CI 1.7-4.1], 3.3 [CI 1.9-5.8]). The same was true of the analysis of average or cumulative smoking consumption, and also of analyses stratified by different histological types. We conclude that for comparable exposure to tobacco smoke, the risk of lung cancer is comparable in women and men.  相似文献   
42.
Between 1992 and 1997 we conducted a case-control study of oesophageal cancer in 3 areas of northern Italy. Cases were 304 patients (29 women), ages 39-77 years (median age 60 years), with a first incident squamous-cell carcinoma (SCC) of the oesophagus. Controls were 743 patients (150 women), ages 35-77 years (median age 60 years), admitted for acute illnesses, unrelated to tobacco and alcohol, to major hospitals of the areas under surveillance. We derived estimates of daily dietary intake of 6 macronutrients, cholesterol, and 20 micronutrients or minerals from a validated food-frequency questionnaire, including 78 food groups and recipes and 15 questions on individual eating patterns. After allowance for age, gender, area of residence, education, body mass index, physical activity, smoking habit, alcohol consumption and energy intake, most micronutrients were inversely associated with oesophageal SCC risk. Highly significant associations emerged for monounsaturated fatty acids [odds ratio (OR) in highest vs. lowest intake quintile = 0.5]; carotene (OR = 0.3); lutein + zeaxanthin (OR = 0.4); vitamin C (OR = 0.4); and niacin (OR = 0.5). Only retinol appeared to be positively related to risk (OR = 1.9). The effect of the above nutrients, expressed as ORs, appeared to be similar in non-smokers and smokers, and non/light drinkers and heavy drinkers.  相似文献   
43.
32D cells expressing v-Ha-Ras fail to show a transformed phenotype. Since Ras requires an active IGF-1R for transformation of fibroblasts, we asked whether expression of IRS-1 or Shc (two of the major substrates of the IGF-1R) could co-operate with oncogenic Ras in transforming 32D cells. We find that IRS-1, but not Shc, in combination with v-Ha-Ras generates a fully transformed phenotype in 32D cells. 32D cells expressing both IRS-1 and v-Ha-Ras (32D/IRS1/Ras) survive and proliferate in the absence of IL-3, do not undergo granulocytic differentiation in the presence of G-CSF and form tumors in nu/nu and syngeneic mice. In contrast, 32D cells expressing singly IRS-1 or v-Ha-Ras exhibit only a block in differentiation capacity. Over-expression of Shc proteins, by itself, promotes differentiation of 32D cells. Concomitant expression of IRS-1 and v-Ha-Ras synergistically phosphorylates ERK-1 and ERK-2 whereas a MEK inhibitor rapidly induces death of 32D/IRS1/Ras transformed cells. Furthermore, transformed 32D/IRS1/Ras cells display high levels of PI3-K activation and undergo rapid apoptosis when exposed to PI3-K inhibitors. The data indicate that: (1) a fully transformed phenotype in 32D cells is generated when a block in differentiation (v-Ha-Ras) is coupled with another differentiation block (IRS-1); (2) PI3-K and MAPK activity are required for the survival of transformed cells; (3) the signals generated by IRS-1 and oncogenic Ras converge on ERK and PI3-K resulting in high levels of activation.  相似文献   
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OBJECTIVE: In patients with severe pulmonary hypertension associated with congenital heart disease, we prefer to perform repair of the congenital heart disease and lung transplantation whenever feasible so as to augment the donor pool and avoid the cardiac complications associated with heart transplantation. We report our experience with repair of congenital heart disease and lung transplantation and compare the results with those of patients who underwent heart-lung transplantation during the same period. METHODS: The records of patients who had repair of congenital heart disease and lung transplantation (n = 35) and heart-lung transplantation (n = 16) between 1990 and 2003 were reviewed. RESULTS: The underlying congenital heart disease in the repair of congenital heart disease and lung transplantation group included transposition of great vessels (n = 2), atrioventricular canal defect (n = 2), ventricular septal defect (n = 9), pulmonary venous obstruction (n = 7), scimitar syndrome (n = 2), pulmonary arterial atresia or stenosis (n = 5), and others (n = 8). Thirteen of the patients undergoing repair of congenital heart disease and lung transplantation (37.1%) had the congenital heart disease repaired before lung transplantation; the remaining congenital heart disease repairs were performed concurrently with transplantation. Sixteen patients underwent heart-lung transplantation because of poor left ventricular function or single-ventricle anatomy. Freedoms from bronchiolitis obliterans at 1, 3, and 5 years were 72.9%, 54.7%, and 54.7% for the repair of congenital heart disease and lung transplantation group and 77.8%, 51.9%, and 38.9% for the heart-lung transplantation group, respectively. Survivals at 1, 3, and 5 years were 62.9%, 51.4%, and 51.4% for the repair of congenital heart disease and lung transplantation group and 66.5%, 66.5%, and 60% for the heart-lung transplantation group, respectively. CONCLUSION: Repair of congenital heart disease and lung transplantation is a feasible treatment option. Long-term outcome is determined by associated complications related to lung transplantation. Despite the complexity of combined congenital heart disease repair with lung transplantation and the resulting perioperative morbidity, the patients had similar outcomes to those of patients who underwent heart-lung transplantation.  相似文献   
46.
Aim: To evaluate the effect of different approaches to treatment of smoking as a potential confounder in an occupational study of lung cancer.

Methods: Data were used from a case–control study on 956 men with lung cancer and 1253 population controls recruited in two northern Italian areas during 1990–1992. The risk of lung cancer associated with 11 selected job titles and eight selected industrial activities was estimated using seven different methods to treat smoking history. To evaluate the confounding effect of smoking, odds ratios obtained using the first six models were compared with estimates from the seventh and most complex model, in which cumulative tobacco consumption and time since cessation were considered.

Results: Although crude odds ratios for some of the occupational categories were biased by up to 25%, such bias decreased to less than 10% when a simple model including smoking status (never, ex-, current) was used.

Conclusions: In occupational studies on lung cancer risk, information on smoking status may allow satisfactory control of the potential confounding effect of the habit.

  相似文献   
47.
The aim of this study was to evaluate the parasitemia variation of three Hepatozoon species in Brazilian snakes. This study was conducted between 2001 and 2003 and included Hepatozoon terzii from Boa constrictor amarali, and Hepatozoon migonei and Hepatozoon cyclagrasi from Hydrodynastes gigas. It was observed that the parasitemia tended to decrease in all three Hepatozoon species but the parasites were not eliminated. This data suggest that Hepatozoon infection may be similar to Toxoplasma gondii infection, in that it persists throughout host life.  相似文献   
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49.
The interpretation of the evidence linking exposure to secondhand smoke with lung cancer is constrained by the imprecision of risk estimates. The objective of the study was to obtain precise and valid estimates of the risk of lung cancer in never smokers following exposure to secondhand smoke, including adjustment for potential confounders and exposure misclassification. Pooled analysis of data from 2 previously reported large case-control studies was used. Subjects included 1263 never smoking lung cancer patients and 2740 population and hospital controls recruited during 1985-1994 from 5 metropolitan areas in the United States, 11 areas in Germany, Italy, Sweden, United Kingdom, France, Spain and Portugal. Odds ratios (ORs) of lung cancer were calculated for ever exposure and duration of exposure to secondhand smoke from spouse, workplace and social sources. The OR for ever exposure to spousal smoking was 1.18 (95% CI = 1.01-1.37) and for long-term exposure was 1.23 (95% CI = 1.01-1.51). After exclusion of proxy interviews, the OR for ever exposure from the workplace was 1.16 (95% CI = 0.99-1.36) and for long-term exposure was 1.27 (95% CI = 1.03-1.57). Similar results were obtained for exposure from social settings and for exposure from combined sources. A dose-response relationship was present with increasing duration of exposure to secondhand smoke for all 3 sources, with an OR of 1.32 (95% CI = 1.10-1.79) for the long-term exposure from all sources. There was no evidence of confounding by employment in high-risk occupations, education or low vegetable intake. Sensitivity analysis for the effects of misclassification (both positive and negative) indicated that the observed risks are likely to underestimate the true risk. Clear dose-response relationships consistent with a causal association were observed between exposure to secondhand smoke from spousal, workplace and social sources and the development of lung cancer among never smokers.  相似文献   
50.
Among the cereals, wheat, rye, barley and oats, have been reported to cause protein contact dermatitis. However, in these cases neither the involvement of an immunological mechanism nor the role of specific protein(s) has been demonstrated. We present a case of protein contact dermatitis from corn. The patient presented with a Type I sensitization to corn, as shown by the presence of specific immunoglobulin (Ig)E and positivity to prick tests with both a flour suspension and the salt-soluble protein fraction of this cereal. The same corn preparations induced a strong urticarial reaction on scratch testing. This reaction was followed several days later by the appearance of erythema and then eczema at the site of application. When boiled, these preparations became inactive on both prick and scratch testing. Patch tests were negative in all cases. Immunoblotting performed with the patient's serum showed the presence of a unique IgE-binding protein band with a molecular weight of around 14 kDa, belonging to the salt-soluble corn protein fraction. Our results give the first clear evidence that cornflour can induce protein contact dermatitis. The IgE-binding 14-kDa protein has characteristics identical to those of the trypsin/alpha-amylase inhibitors from cereals.  相似文献   
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