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This molecular epidemiologic case-control study of lung cancer incorporated three complementary biomarkers: the glutathione S- transferase M1 (GSTM1) null genotype, a potential marker of susceptibility, and polycyclic aromatic hydrocarbon-DNA adducts (PAH- DNA) and sister chromatid exchanges (SCE), both indicators of environmentally induced genetic damage. Associations between biomarkers and lung cancer were investigated, as were possible gene-environment interactions between the GSTM1 null genotype and tobacco smoke exposure. Subjects included 136 primary non-small cell lung cancer surgical patients and 115 controls at the Columbia Presbyterian Medical Center. Questionnaire and Tumor Registry data, pre-treatment blood samples and biomarker measurements on blood were obtained. Overall, GSTM1 null genotype was significantly associated with lung cancer [odds ratio (OR) = 2.04, 95% confidence interval (CI) = 1.13-3.68]. ORs for GSTM1 and lung cancer were significant in females (2.50, 1.09-5.72) and smokers (2.25, 1.11-4.54) and not significant in males (1.4, 0.58-3.38) and non-smokers (0.88, 0.18-4.33). However, ORs for males versus females and smokers versus non-smokers did not differ significantly. The OR for GSTM1 and lung cancer in female smokers was 3.03 (1.09- 8.40), compared with 1.42 (0.53-4.06) in male smokers. In contrast to PAH-DNA adducts in leukocytes, SCE did not differ between cases and controls. Neither biomarker differed significantly between the two GSTM1 genotypes. The combined effect of elevated PAH-DNA adducts and GSTM1 genotype on case-control status (16.19, 1.2-115) appeared multiplicative. Results suggest that the effect of the GSTM1 null genotype is greatest in female smokers, which is consistent with other evidence that indicates that women are at higher risk of lung cancer than males, given equal smoking. Persons with both the GSTM1 deletion and elevated PAH-DNA adducts may represent a sensitive subpopulation with respect to carcinogens in tobacco smoke and other environmental media.   相似文献   
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OBJECTIVE: To examine the relationship between alcohol intake and survival in elderly people. DESIGN AND SETTING: A prospective study over 116 months of non-institutionalised subjects living in Dubbo, a rural town (population, 34,000) in New South Wales. PARTICIPANTS: 1235 men and 1570 women aged 60 years and over who were first examined in 1988-89. MAIN OUTCOME MEASURES: All-causes mortality; gross cost of alcohol per life-year gained. RESULTS: Death occurred in 450 men and 392 women. Intake of alcohol was generally moderate (i.e., less than 14 drinks/week). Any intake of alcohol was associated with reduced mortality in men up to 75 years and in women over 64 years. In a proportional hazards model, the hazard ratio for mortality in men taking any alcohol was 0.63 (95% CI, 0.47-0.84) and in women was 0.75 (95% CI, 0.60-0.94). Cardiovascular deaths in men were reduced from 20/100 (95% CI, 14-26) to 11/100 (95% CI, 9-13) and in women from 16/100 (95% CI, 13-19) to 8/100 (95% CI, 6-10). The reduction in mortality occurred in men and women taking only 1-7 drinks/week--hazard ratios, 0.68 (95% CI, 0.49-0.94) and 0.78 (95% CI, 0.61-0.99), respectively, with a similar protective effect from intake of beer or other forms of alcohol. After almost 10 years' follow-up, men taking any alcohol lived on average 7.6 months longer, and women on average 2.7 months longer, compared with non-drinkers. The gross cost for alcohol per life-year gained if consuming 1-7 drinks/week was $5700 in men, and $19,000 in women. CONCLUSIONS: Moderate alcohol intake in the elderly appears to be associated with significantly longer survival in men 60-74 years and in all elderly women.  相似文献   
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OBJECTIVES: To explore patient views on participation in treatment, physical care and psychological care decisions and factors that facilitate and hinder patients from making decisions. DESIGN: Qualitative study using semi-structured interviews with patients. SETTING AND PARTICIPANTS: Three NHS Trusts in the north-west of England. Theoretical sampling including 41 patients who had been treated for colorectal cancer. RESULTS: For patients, participation in the decision-making process was about being informed and feeling involved in the consultation process, whether patients actually made decisions or not. The perceived availability of treatment choices (surgery, radiotherapy, chemotherapy) was related to type of treatment. Factors that impacted on whether patients wanted to make decisions included a lack of information, a lack of medical knowledge and trust in medical expertise. Patients perceived that they could have a more participatory role in decisions related to physical and psychological care. CONCLUSION: This study has implications for health professionals aiming to implement policy guidelines that promote patient participation and shared partnerships. Patients in this study wanted to be well informed and involved in the consultation process but did not necessarily want to use the information they received to make decisions. The presentation of choices and preferences for participation may be context specific and it cannot be assumed that patients who do not want to make decisions about one aspect of their care and treatment do not want to make decisions about other aspects of their care and treatment.  相似文献   
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Intraabdominal abscess rate after laparoscopic appendectomy   总被引:2,自引:0,他引:2  
BACKGROUND: Studies suggest increased intraabdominal abscess (IA) rates following laparoscopic appendectomy (LA), especially for perforated appendicitis. Consequently, an open approach has been advocated. The aim of our study is to compare IA rates following LA performed by a laparoscopic surgery and a general surgical service within the same institution. METHODS: Data of LA patients treated at Los Angeles County-University of Southern California (LAC-USC) Medical Center between March 1992 and June 1997 were reviewed. The main outcome measure was postoperative IA. RESULTS: In all, 645 LA were reviewed. A total of 413 LA (285 acute, 61 gangrenous, 67 perforated appendicitis) were performed by three general surgical services (10 attendings). Ten abscesses occurred postoperatively (2.4%), 6 with perforated appendicitis. After the laparoscopic service was introduced, 232 standardized LA (126 acute, 46 gangrenous, 60 perforated) were performed by two attendings. One IA occurred (gangrenous appendicitis). The IA rate for perforated appendicitis was significantly lower on the laparoscopic service (P = 0.025). There was no difference in IA rates for acute and gangrenous appendicitis. There was no mortality in either group. CONCLUSION: IA rate following LA for perforated appendicitis was significantly reduced on the laparoscopic service. Mastery of the learning curve and addition of specific surgical techniques explained this improved result. Therefore, laparoscopic appendectomy for complicated appendicitis may not be contraindicated, even for perforated appendicitis.  相似文献   
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BACKGROUND: Although nitrous oxide (N2O) is used commonly during anesthesia, clinically relevant advantages-disadvantages of using this agent are not well established in the ambulatory setting. This study in women undergoing ambulatory gynecologic surgery compares outcomes in patients administered total intravenous anesthesia with propofol versus the propofol plus N2O. The primary outcome was the time to home readiness. Secondary outcomes included the incidence of postanesthetic adverse events. METHODS: Women presenting for elective ambulatory termination of pregnancy or gynecologic laparoscopy were induced with an intravenous sleep dose of propofol and fentanyl. After induction, subjects were randomly allocated to maintenance anesthesia with propofol alone or propofol plus 65% N2O. Patients were assessed by a blinded observer in the postanesthetic care unit at 20-min intervals to determine home readiness. Postoperative pain and nausea were measured with visual analog scales. Postoperative analgesics and antiemetics were recorded. The incidence of adverse events occurring after hospital discharge was assessed by a telephone interview 24 h postoperatively. RESULTS: A total of 740 patients received propofol alone, and 750 patients received propofol plus N2O. Mean home readiness times were not significantly different between treatment groups. There were no significant differences between groups in pain scores, nausea scores, analgesia administration, or antiemetic administration before discharge. There were no significant differences in the frequency of adverse events for 24 h after discharge from hospital. CONCLUSIONS: Omission of N2O from a propofol-based anesthetic for ambulatory gynecologic surgery does not affect time to home readiness or the incidence of postoperative adverse events up to 24 h after discharge from hospital. (Key words: Awareness; outpatient surgery; total intravenous anesthesia.)  相似文献   
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