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71.
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   
72.
Aims: To assess maternal compliance with nutritional recommendations in an allergy preventive programme, and identify factors influencing compliance behaviour. Methods: Randomised double-blind intervention study on the effect of infant formulas with reduced allergenicity in healthy, term newborns at risk of atopy. Maternal compliance with dietary recommendations concerning milk and solid food feeding was categorised. Results: A total of 2252 newborns were randomised to one of four study formulas. The drop out rate during the first year of life was 13.5% (n = 304). The rates of high, medium, and low compliance to milk feeding during weeks 1–16 were 83.4%, 4.0%, and 7.5%; the corresponding rates to solid food feeding during weeks 1–24 were 60.0%, 12.1%, and 22.9%. In 5.1% of subjects no nutritional information was available. Low compliance was more frequent among non-German parents, parents with a low level of education, young mothers, smoking mothers, and those who weaned their infant before the age of 2 months. Conclusions: Evaluation of allergy preventive programmes should take into account non-compliance for assessing the preventive effectiveness on study outcome.  相似文献   
73.
It was the aim of the study to examine the efficacy of silver coated prostheses in comparison to Rifampin in impregnated prostheses in the prevention of vascular graft infections. MATERIAL AND METHODS: 24 C3H/HcN mice with a bodyweight between 24 and 27 grams were assigned to four different groups. GROUP I: control gel-sealed Dacron graft (Uni-Graft DV) (6), GROUP II: gel-sealed Dacron graft (Uni-Graft DV) contaminated locally with 2 x 10(7) CFU/1.2 ml Staphylococcus aureus ATCC 25923 (6), GROUP III: silver prosthesis (Intergard Silver) contaminated locally with 2 x 10(7) CFU/0.2 ml Staphylococcus aureus ATCC 25923 (6), GROUP IV: Rifampin impregnated prosthesis contaminated locally with 2 x 10(7) CFU/0.2 ml Staphylococcus aureus ATCC 25923 (6). 14 days after primary operation all animals were euthanized and the grafts harvested. Specimens were examined for signs of infections by histology and microbiology. RESULTS: At termination of the trial on day 14 none of the grafts of group I were contaminated. 6 out of 6 grafts in group II, 6 out of 6 grafts in group III and 1 out of 6 grafts in group IV presented with infected grafts. The use of antimicrobial Rifampin could significantly prevent infection after bacterial challenge in group IV. CONCLUSION: The silver protected prosthesis (Intergard Silver) seems to be not effective in protecting vascular infection in vivo. However, the Rifampin group showed excellent results. In conclusion Rifampin bonded gelatin-sealed Dacron grafts are significantly more resistant to bacteremic infection than are silver/collagen-coated Dacron grafts.  相似文献   
74.
Based on a large single-center follow-up database, we evaluated the long-term results after curative resection of pulmonary metastases from renal cancer. During a 20-year period, 105 patients underwent a total of 150 resections with curative intention. Hospital mortality was 0.95%, 5- and 10-year survival rates were 40% and 33%, respectively. Significant prognostic relevance was shown for complete pulmonary resection, lymph node involvement upon primary resection as well as size of the resected lung metastasis. Our findings of low perioperative morbidity and mortality rates lead us to propose that in patients without additional metastases curative resection of pulmonary lesions should be considered. Moreover, recurrent pulmonary metastases should also be considered for surgical treatment since resection for cure significantly improves survival in these patients.  相似文献   
75.
Hormonal factors and risk of lung cancer among women?   总被引:3,自引:0,他引:3  
BACKGROUND: Gender differences in the histological distribution of lung carcinoma and a possibly greater susceptibility of women than men to tobacco carcinogens, suggest a possible influence of sex-specific hormones. This study examines endocrine factors and risk of lung cancer among women by smoking status and histology. METHODS: We used data of a case-control study on lung cancer conducted from 1990 to 1996 in Germany, including 811 histologically confirmed female cases and 912 female population controls. Information on various menstrual and reproductive factors, use of oral contraceptives (OC), hormone replacement therapy (HRT), and smoking was gathered through personal interviews using a structured questionnaire. Odds ratios (OR) and 95% CI adjusted for age, region, smoking, and education were calculated via logistic regression. RESULTS: A reduction in lung cancer risk was observed with the use of OC (OR = 0.69; 95% CI: 0.51-0.92), but no trend in risk with increasing duration of use, age at first use, or calendar year of first use was present. A history of HRT was associated with a reduced risk (OR = 0.83; 95% CI: 0.64-1.09), particularly after long duration (>/=7 years) (OR = 0.59; 95% CI: 0.37-0.93). No clear association was found with regard to age at menarche, length of menstrual cycle, number of live-births, and age at menopause. Overall results did not differ much by histological cell subtype. The reduction in lung cancer risk associated with the use of exogenous hormones was primarily seen among smoking women. CONCLUSIONS: Our data provide evidence for a possible role of hormonal factors in the aetiology of lung cancer in women.  相似文献   
76.
Zusammenfassung Die Anordnung einer strikten Nahrungskarenz nach Mitternacht vor operativen Eingriffen in Narkose ist die geläufige Praxis in chirurgischen Einrichtungen in Deutschland. Das damit verfolgte Ziel ist eine Reduktion des perioperativen Aspirationsrisikos. Seit mehreren Jahren wird die wissenschaftliche Grundlage dieser Verfahrensweise zunehmend kritisch diskutiert. Insbesondere für die präoperative Einnahme von Wasser und klarer Flüssigkeit zeigen experimentelle wie klinische Untersuchungen, dass von einer vollständigen Magenpassage innerhalb von 2 h sicher ausgegangen werden kann und das Risiko nach begrenztem Trinken bis 2 h vor elektiven Operationen in Allgemeinanästhesie nicht erhöht ist. Zudem sind perioperative Aspirationszwischenfälle sehr selten, haben eine gute Prognose und sind eher auf Faktoren wie mangelnde Narkosetiefe oder unzureichende Atemwegsprotektion zurückzuführen als auf den Nüchternheitsstatus des Patienten. Folglich haben zahlreiche nationale anästhesiologische Gesellschaften im Sinne eines verbesserten perioperativen Wohlbefindens der Patienten ihre offiziellen Leitlinien zur präoperativen Nüchternheit geändert und empfehlen unter Berücksichtigung definierter Einschränkungen und Kontraindikationen einen gelockerten Umgang mit der Einnahme flüssiger wie fester Nahrung vor elektiven Eingriffen. Die vorliegende Arbeit gibt eine zusammenfassende Übersicht über die Hintergründe, auf denen diese national erstellten Leitlinien beruhen, mit der Absicht auch für Deutschland eine Empfehlung zur Lockerung der präoperativen Nüchternheit für klare Flüssigkeiten vorzuschlagen.  相似文献   
77.
78.
The gamma knife is a stereotactic radiosurgery device which allows well defined, deep seated brain tumors or arteriovenous malformations with a maximal volume of about 25 ccm and a diameter not greater than 3.5 cm, to be treated in a single session under local anesthesia. The gamma knife offers an alternative treatment method to the classical approach of treating brain metastases by surgical excision and/or whole brain radiotherapy. The advantages of this technique are evident: the method is non-invasive, the treatment is carried out in a single session with a very short hospitalisation of two to three days, it is exempt from physical and psychical stress, the head does not need to be shaved and no hair loss occurs, a good quality of life is obtained for a reasonably prolonged survival time and it offers an economically favourable treatment method. Up to December 1999, over 30,000 patients suffering from brain metastases have been treated worldwide using the gamma knife. In Zürich, from September 1994 to December 2000 140 received this treatment. In the literature selection criteria may differ, and this may have determined some of differences in outcome. However, our results are comparable with those in the majority of publications with an average survival time of 263 days and a maximum survival of 1080 days. Good prognostic factors for survival and local control of brain metastases are a Karnofsky Performance Scale Score approaching 90 to 100, but not lower than 70, tumour volume, controlled primary cancer, and absence or stable extracranial metastases.  相似文献   
79.
PURPOSE: Preoperative chemoradiotherapy for advanced rectal cancer has been an important therapeutic tool to improve the long-term results of curative resection. It is not known whether preoperative chemoradiotherapy for advanced rectal cancer influences the perioperative course of immune parameters. METHODS: Thirty patients with rectal cancer underwent surgery with (study group, n = 15) or without (control group, n = 15) preoperative chemoradiotherapy (2 cycles of 5-fluorouracil, 45 Gy). Blood samples were taken before neoadjuvant therapy, preoperatively, and on Days 1, 2, and 5 after surgery. Cell numbers of lymphocyte subpopulations, granulocytes, monocytes, and natural killer cells were determined by flow cytometry; tumor necrosis factor- and interleukin-6 serum levels were measured with enzyme-linked immunosorbent assay. RESULTS: Significant differences between study and control patients (P < 0.05) were detected regarding circulating interleukin-6 and tumor necrosis factor- levels, with depression of the proinflammatory response to surgery in study patients. Similarly, granulocytosis and monocytosis after surgery were significantly lower in patients after neoadjuvant therapy. Furthermore, cell counts of total T lymphocytes, T helper cells, B lymphocytes, and natural killer cells were significantly reduced after preoperative chemoradiotherapy. This depression of cell-mediated immunity in study patients was even more pronounced after surgery. CONCLUSIONS: Preoperative chemoradiotherapy for advanced rectal cancer results in a significant preoperative and postoperative immune dysfunction as indicated by depression of lymphocyte subpopulations, monocytes, granulocytes, and proinflammatory cytokine release. These findings are of importance because increased perioperative morbidity and mortality rates have been observed after preoperative chemoradiotherapy.  相似文献   
80.
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