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51.
PURPOSE: To evaluate the risk of second cancers after cervical cancer treated with radiotherapy for Asian populations. METHODS AND MATERIALS: We reviewed 2,167 patients with cervical cancer undergoing radiotherapy between 1961 and 1986. Intracavitary brachytherapy was performed with high-dose rate source (82%) or low-dose rate source (12%). Relative risk (RR), absolute excess risk (AR), and cumulative risk of second cancer were calculated using the Japanese disease expectancy table. For 1,031 patients, the impact of smoking habit on the increasing risk of second cancer was also evaluated. RESULTS: The total number of person-years of follow-up was 25,771, with 60 patients being lost to follow-up. Among the 2,167 patients, 1,063 (49%) survived more than 10 years. Second cancers were observed in 210 patients, representing a significant 1.2-fold risk (95% confidence interval [CI], 1.1-1.4) of developing second cancer compared with the general population, 1.6% excess risk per person per decade of follow-up, and elevating cumulative risk up to 23.8% (95% CI, 20.3-27.3) at 30 years after radiotherapy. The RR of second cancer was 1.6-fold for patients with the smoking habit and 1.4-fold for those without. CONCLUSIONS: Small but significant increased risk of second cancer was observed among Japanese women with cervical cancer mainly treated with high-dose rate brachytherapy. Considering the fact that about half of the patients survived more than 10 years, the benefit of radiotherapy outweighs the risk of developing second cancer.  相似文献   
52.
Background: Tamoxifen (TAM) is a selective estrogen receptor modulator (SERM) that is widely used as adjuvant therapy in breast cancer patients; however, it is also associated with undesirable side effects. The goal of this study was to investigate TAM-related side effects, and determine profiles of side effects by race and by smoking status. Methods: A secondary data analysis was conducted using cross-sectional study data from 138 African American and Caucasian women with breast cancer taking TAM 20 mg daily for at least 30 days prior to enrollment. Participants completed questionnaires that obtained information about demographic characteristics, reproductive history, health and lifestyle characteristics, TAM use and its related side effects. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals. Results: Compared to never smokers, a significantly greater percentage of current smokers reported ever experiencing TAM-related nausea (28.0% versus 5.0%, P = 0.007), depression (40.0% versus 7.1%, P = 0.001) and migraines (19.2% versus 1.7%, P = 0.02). These differences remained statistically significant after controlling for race, age, obesity, tumor stage, and duration of TAM treatment. No significant differences by race were noted in women reporting TAM side effects. Conclusion: The findings from this study suggest that current smokers with breast cancer should be informed of the increased probability of reporting TAM-related side effects such as nausea, depression and migraines, and counseled about smoking cessation which may reduce the incidence of these side effects.  相似文献   
53.
This study examined the ability of a backpropagation neural network (BPNN) classifier to distinguish between current and former smokers in the 2000 National Health Interview Survey (NHIS) sample adult file. The BPNN classifier performance exceeded that of random chance, with asymmetric 95% confidence intervals for Az (area under receiver operating characteristic curve) = (0.7532, 0.7790). Separation of current and former smokers was imperfect, as illustrated by the receiver operating characteristic (ROC) curve. Additionally, performance did not exceed that of a comparison classifier created using logistic regression. Attribute subset selection identified three novel attributes related to smoking cessation status. This study establishes the ability of backpropagation neural networks to classify a complex health behavior, smoking cessation. It also illustrates the hypothesis-generating capacity of data mining methods when applied to large population-based health survey data. Ultimately, BPNN classifiers of smoking cessation status may be useful in decision support systems for smoking cessation interventions.  相似文献   
54.
OBJECTIVE: Bupropion was developed for the treatment of depression, but subsequently was found to be effective for smoking cessation. To date, there are no prospective comparative studies examining its safety in pregnancy. The primary objective was to determine whether bupropion increases the risks for major malformations above baseline. The secondary objective was to examine the rates of live births, stillbirths, spontaneous and therapeutic abortions, mean birth weight, and gestational age at birth. STUDY DESIGN: Women who were pregnant or planning a pregnancy and taking bupropion were enrolled in the study. Follow-up of pregnancy outcome was carried out between 4 months and 1 year after delivery. Three comparisons were carried out: 1) women exposed to bupropion vs a nonteratogen group; 2) those taking for depression vs other antidepressants, vs a nonteratogen group; 3) spontaneous abortions were compared between those taking for depression, vs another antidepressant group vs a nonteratogen group. RESULTS: We completed follow-up on 136 women exposed to bupropion during the first trimester of pregnancy. There were (105) live births, no major malformations, the mean birth weight was (3450g), the mean gestational age at delivery was (40 weeks), the number of spontaneous abortions was 20, there were 10 therapeutic abortions, there was 1 stillbirth, and 1 neonatal death. There were no statistically significant differences between any of the end points we examined between the exposed and comparison groups, with the exception of significantly more spontaneous abortions in the bupropion group (P = .009). CONCLUSION: These results suggest that bupropion does not increase the rates of major malformation above baseline. The higher rates of spontaneous abortions are similar to other studies examining the safety of antidepressants during pregnancy.  相似文献   
55.
Lung cancer generally carries a poor prognosis and the determinants of survival have been of interest. However, survival estimates in Asian populations are scarce. This study describes survival rates and their determinants in Singapore Chinese women, a primarily non-smoking population. Three hundred and twenty-six Chinese women, diagnosed with primary lung carcinoma in three major hospitals in Singapore between April 1996 and December 1998, were followed up till 31 December 2000. The Kaplan–Meier method was used for survival analysis. Two hundred and eighty (85.7%) died from the disease during follow-up. The median survival time was 0.7 years and the three-year survival was 15.8%. These survival rates are similar to those of Western populations, and they provide a basis for examining trends over time. Age at diagnosis was an independent prognostic factor [adjusted hazard ratio (relative risk) 1.4, 95% confidence intervals (CI) 1.1–1.9 for women above 65 years relative to younger women]. Most (70.5%) tumours were stage III/IV at diagnosis. Three-year survival ranged from 72% among patients with stage I tumours to 7% for stage IV tumours. Overall, there was no survival difference among different histological types in all stages combined. When limited to stages I and II cancers, adenocarcinomas were associated with a better outcome relative to other histological subtypes combined (adjusted relative risk 0.4, 95% CI 0.1–1.0). Smoking was an independent risk factor (adjusted relative risk 1.3, 95% CI 1.0–1.8). Nevertheless, non-smokers comprised 57.4% of this series, highlighting the importance of increased awareness among health professionals and the public that lung cancer is not only a disease of smokers. The high proportion of late-stage tumours in this study and the impact of disease stage on outcome underline the importance of early detection in improving survival of lung cancer.  相似文献   
56.
57.
In this paper the association between smoking history, beverage consumption, diet and bladder cancer incidence is systematically reviewed. A rating system has been used to summarise the level of scientific evidence (i.e. convincing, probable, possible, and no evidence) and the level of association (i.e. substantially increased, (RR2.5), moderately increased (1.5RR<2.5), slightly increased (1.2RR<1.5), no association (0.8RR<1.2), slightly decreased (0.7RR<0.8), moderately decreased (0.4RR<0.7), and substantially decreased (RR<0.4)). There is convincing evidence that cigarette smoking status, frequency and duration substantially increase the risk of bladder cancer. However, the evidence is not clear for other forms of smoking. A small increased risk for cigar, pipe, and environmental smoking is only possible. There is possible evidence that total fluid intake is not associated with bladder cancer. Although there is convincing evidence for a positive association between alcohol consumption and bladder cancer risk in men, the risk is small and not clinically relevant. Coffee and tea consumption are probably not associated with bladder cancer. The authors conclude that total fruit consumption is probably associated with a small decrease in risk. There is probably no association between total vegetable intake, vitamin A intake, vitamin C intake and bladder cancer and a possibly moderate inverse association with vitamin E intake. Folate is possibly not associated with bladder cancer. There probably is a moderate inverse association between selenium intake and bladder cancer risk.  相似文献   
58.
We previously showed that maternal exposure to nicotine, alone or in combination with chlorpyrifos, caused an increase in glial fibrillary acidic protein (GFAP) immunostaining in the CA1 subfield of hippocampus and cerebellum in postnatal day (PND) 30 offspring. In the present study, PND 60 offspring were evaluated for histopathological and cholinergic effects following maternal exposure to nicotine and chlorpyrifos, alone and in combination. Timed-pregnant Sprague-Dawley rats (300–350 g) were treated daily with nicotine (1 mg/kg, s.c., in normal saline) or chlorpyrifos (0.1 mg/kg, dermal, in ethanol) or a combination of nicotine and chlorpyrifos from gestational days (GD) 4 to 20. Control animals were treated with saline and ethanol. On PND 60, the offspring were evaluated for cholinergic changes and pathological effects. Plasma butyrylcholinesterase (BChE) activity in the female offspring from chlorpyrifos treated mothers showed a significant increase (~183% of control). Male offspring from mothers treated with either chlorpyrifos or nicotine alone showed a significant increase in the acetylcholinesterase (AChE) activity in the brainstem while female offspring from mothers treated with either nicotine or a combination of nicotine and chlorpyrifos showed a significant increase (~134 and 126% of control, respectively) in AChE activity in the brainstem. No significant changes were observed in the ligand binding densities for 42 and 7 nicotinic acetylcholine receptors in the cortex. Histopathological evaluation using cresyl violet staining showed a significant decrease in surviving Purkinje neurons in the cerebellum of the offspring from nicotine treated mothers. An increase in GFAP immunostaining in cerebellar white matter was observed in the offspring from the mothers treated with nicotine. These results suggest that maternal exposure to real-life levels of nicotine and/or chlorpyrifos causes differential regulation of brainstem AChE activity. Also, nicotine caused a decrease in the surviving neurons and an increased expression of GFAP in cerebellar white matter of the offspring on PND 60. These changes can lead to long-term neurological adverse health effects later in life.  相似文献   
59.
目的了解松江区居民的被动吸烟状况及对吸烟的态度和认识。方法采用分层随机抽样的方法,在医院、商场、车站候车室、政府对外办公大楼等四类公共场所,随机抽取200名松江居民进行问卷调查。结果200名调查对象中不吸烟或已戒烟者共117人,占有58.5%;不吸烟者中被动吸烟率为48.7%,男女间被动吸烟情况没有显著性差异。55.6%的被动吸烟者认为绝大部分吸烟者当面吸烟前从不征求他们意见,只有10.3%的被动吸烟者每次都会表达反对意见。93%的调查对象都能认识到吸烟对吸烟者的危害,但有15%左右的调查对象不清楚吸烟对周围被动吸烟人群的危害。80%左右的调查对象赞成在医院和学校全部禁烟,而有40%左右的调查对象赞成在办公室、餐厅和酒吧实行部分禁烟。结论松江区居民的被动吸烟情况比较严重,居民对被动吸烟的危害认识不足,需要加强被动吸烟的干预工作。  相似文献   
60.
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