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Passive smoking and lung cancer in Swedish women   总被引:3,自引:0,他引:3  
The relation between passive smoking and lung cancer was examined by means of a case-control study in a cohort of 27,409 nonsmoking Swedish women identified from questionnaires mailed in 1961 and 1963. A total of 77 cases of primary carcinoma of the bronchus or lung were found in a follow-up of the cohort through 1980. A new questionnaire in 1984 provided information on smoking by study subjects and their spouses as well as on potential confounding factors. The study revealed a relative risk of 3.3, constituting a statistically significant increase (p less than 0.05) for squamous cell and small cell carcinomas in women married to smokers and a positive dose-response relation. No consistent effect could be seen for other histologic types, indicating that passive smoking is related primarily to those forms of lung cancer which show the highest relative risks in smokers.  相似文献   
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The relationship between the use of cigarettes and other tobacco products and the risk of multiple myeloma was examined in a cohort of nearly 250,000 American veterans followed prospectively for 26 years. Compared with men who had never used tobacco, the risk of death from myeloma was not increased among current (relative risk [RR]=0.9, 95 percent confidence interval [CI]=0.8–1.2) or former (RR=1.0, CI=0.8–1.3) cigarette smokers, nor among users of chewing tobacco or snuff (RR=1.0, CI=0.4–2.3). Risk was only slightly and nonsignificantly increased among pipe or cigar smokers (RR=1.2, CI=0.9–1.5). There was no indication of increasing risk with amount of tobacco used or earlier age at first use. With over 90 percent power to detect a 30 percent increased risk of this tumor occuring among current cigarette smokers, this study provides the strongest evidence to date against an association of cigarette smoking with multiple myeloma.Epidemiology and Biometry Program, Division of Cancer Etiology, National Cancer Institute. Westat, Inc. Rockville, MD. National Cancer Institute, 6130 Executive Blvd, Room 418, Rockville, MD 20892, USA.  相似文献   
4.
A single-purpose analogue-computing device is described for the online assessment of the contractile state of the human myocardium from the left ventricular pressure (Plv) data available during routine cardiac catheterisation. Due attention has been paid to the design of the computer circuits so that they will not process pressure phenomena outside the isovolumic contractile period. Either a \(\left( {\frac{1}{{P_{lv} }}\frac{{dP_{lv} }}{{dt}}} \right)_{max} \) or a plain \(\left( {\frac{{dP_{lv} }}{{dt}}} \right)_{max} \) index is presented on a digitalvoltmeter display, thus obviating the need for any graphical extrapolation or additional computation.  相似文献   
5.
Postnatal mice lacking neurotrophin-3 (NT3) are deficient in Merkel cells of touch domes and whisker follicles. We examined the mechanism of Merkel cell loss by immunocytochemistry and electron microscopy. Merkel cell of whisker follicles of NT3 null newborns exhibited decreased immunoreactivity for cytokeratin 8 and contained apoptotic bodies that were positive for cleaved caspase-3, a marker of active apoptosis. By electron microscopy, the Merkel cells displayed aggregation of chromatin along the nuclear membrane, with the marginated chromatin forming caps at the periphery of the nucleus. Ribosomes aggregated in the cytoplasm, while dense core granules characteristic of Merkel cells were still discernible. Finally, the Merkel cells and their nuclei fragmented into apoptotic bodies. None of the apoptotic Merkel cells were contacted by nerve fibers, and their desmosomal contacts with surrounding keratinocytes disappeared. After postnatal day 6 apoptotic Merkel cells were no longer observed, and the number of surviving Merkel cells was severely reduced. They were flat and contained few osmiophilic granules. We conclude that perinatal apoptosis is responsible for the loss of Merkel cells lacking innervation in NT3 null mice.  相似文献   
6.
S Jablon  Z Hrubec  J D Boice 《JAMA》1991,265(11):1403-1408
Reports from the United Kingdom have described increases in leukemia and lymphoma among young persons living near certain nuclear installations. Because of concerns raised by these reports, a mortality survey was conducted in populations living near nuclear facilities in the United States. All facilities began service before 1982. Over 900,000 cancer deaths occurred from 1950 through 1984 in 107 counties with or near nuclear installations. Each study county was matched for comparison to three "control counties" in the same region. There were 1.8 million cancer deaths in the 292 control counties during the 35 years studied. Deaths due to leukemia or other cancers were not more frequent in the study counties than in the control counties. For childhood leukemia mortality, the relative risk comparing the study counties with their controls before plant start-up was 1.08, while after start-up it was 1.03. For leukemia mortality at all ages, the relative risks were 1.02 before start-up and 0.98 after. For counties in two states, cancer incidence data were also available. For one facility, the standardized registration ratio for childhood leukemia was increased significantly after start-up. However, the increase also antedated the operation of this facility. The study is limited by the correlational approach and the large size of the geographic areas (counties) used. It does not prove the absence of any effect. If, however, any excess cancer risk was present in US counties with nuclear facilities, it was too small to be detected with the methods employed.  相似文献   
7.
Questionnaire data on about 1200 male twin pairs from the Registry at the Karolinska Institute, Stockholm, and on about 4000 male twin pairs from the Registry of the National Research Council, Washington, DC, have been used to study factors affecting angina pectoris. An operational definition of "angina pectoris" was developed from the questionnaire. In the available data, alcohol drinking, lack of exercise, frequent change of employer, low occupational adjustment and smoking are moderately but significantly related to angina among individuals (disregarding twin relationships) in both Sweden and the US. In monozygous US twin pairs discordant for the above variables, significantly different rates of angina appear only with alcohol drinking. In discordant dizygous US twin pairs, significantly different rates of angina appear with alcohol drinking and with low occupational adjustment. Of the independent variables only smoking and drinking are appreciably associated with each other. These findings suggest that alcohol drinking and to a lesser extent occupational adjustment are related to angina directly and not through their association with other factors such as age, genetic background, smoking, physical exercise and early environment.  相似文献   
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This retrospective study assesses and compares perioperative parameters in two groups of patients treated by different operative techniques of laparoscopic surgical staging (LASS) for uterine cancer. Between April 1996 and May 2005, 119 consecutively selected women with cervical cancer (n=30) or clinical stage I endometrial cancer (n=89) underwent laparoscopic assisted vaginal hysterectomy (LAVH), total laparoscopic hysterectomy (TLH) or radical laparoscopic assisted vaginal hysterectomy (RALVH) plus bilateral salpingo-oophorectomy (BSO) and/or lymph node dissection (LND) during a primary surgical procedure using an electrosurgery (ELC, n=37) or ultrasonic (US, n=82) operative technique (harmonic shears, UltraCision). The UltraCision was used as a primary method of dissection and hemostasis from 1999. We were unable to perform prompt and thorough hemostasis in 2 patients from the US group (successful procedure rate 97.5%) because of ineffective post-ultrasonic coagulation of venous paravaginal varices (RALVH procedure) and of vena ovarica varices (LAVH, BSO procedure). The UltraCision was effective in all cases of lymphadenectomy. Successful procedure rate of the ELC operative technique was 100%. There were no statistically significant differences between the groups with regard to operation time, blood loss, hospital stay, and complications. There was a significant difference (P<0.001) in the number of lymph nodes harvested: a mean of 18.1 in the US group and 13.7 in the ELC group. We think that the difference was influenced by an increase in experience with laparoscopic lymph node dissection. The UltraCision operative technique ensures efficient dissection, coagulation, cutting, and grasping for LASS in women with cervical and endometrial cancer.  相似文献   
10.
Objective: Alendronate and calcitonin are antiresorptive drugs that were used for the treatment of postmenopausal osteoporosis and were shown to increase bone mineral density (BMD). However, the effect of both drugs in daily clinical practice may differ from that observed in clinical trials.Method: About 50 postmenopausal osteoporotic women were observed during their first year of treatment. Among them, 32 patients used alendronate and 18 used calcitonin. Lumbar spine and femoral neck BMD were measured by dual energy X-ray absorptiometry (DXA) at baseline and after 1 year of therapy. Biochemical markers (B-ALP – bone-specific alkaline phosphatase, OTC – osteocalcin and DPD/UCr – deoxypyridinoline/creatinine ratio) of bone metabolism were measured at baseline and 6 months later. Patient compliance was assumed by tablet counting and verified at interview. Each patient was further questioned about her attitude towards the treatment, as well as her dairy product intake, physical activity, use of other medications, smoking and social status.Main outcome measure: (1) Annual percent change in BMD in lumbar spine and femoral neck after the one-year treatment with either alendronate or calcitonin. (2) The change in biochemical markers of bone turnover.Results: The lumbar spine BMD significantly increased by 7.0% (P < 0.001), the femoral neck BMD by 4.3% (P < 0.01). OTC, B-ALP and DPD/UCr decreased significantly during the therapy with alendronate. Compliance with therapy was 79% (95% CI 68–90%). In the calcitonin-treated group, the lumbar spine BMD significantly increased by 3.1 % (P < 0.05), while the femoral neck BMD remained unchanged. OTC, B-ALP and DPD/UCr did not change significantly during the treatment with calcitonin. Compliance with calcitonin therapy was 87% (95% CI 63–110%). The annual change of BMD in both treatment groups was independent on all questioned factors.Conclusion: In daily practice, alendronate enhanced significantly BMD both in lumbar spine and femoral neck. Calcitonin showed increase only in the lumbar spine BMD.  相似文献   
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