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Reproductive factors are associated with reduced risk of breast cancer, but less is known about whether there is differential protection against subtypes of breast cancer. Assuming reproductive factors act through hormonal mechanisms they should protect predominantly against cancers expressing oestrogen (ER) and progesterone (PR) receptors. We examined the effect of reproductive factors on subgroups of tumours defined by hormone receptor status as well as histology using data from the NIHCD Women's Contraceptive and Reproductive Experiences (CARE) Study, a multicenter case-control study of breast cancer. We estimated odds ratios (ORs) and 95% confidence intervals (CIs) as measures of relative risk using multivariate unconditional logistic regression methods. Multiparity and early age at first birth were associated with reduced relative risk of ER + PR + tumours (P for trend=0.0001 and 0.01, respectively), but not of ER - PR - tumours (P for trend=0.27 and 0.85), whereas duration of breastfeeding was associated with lower relative risk of both receptor-positive (P for trend=0.0002) and receptor-negative tumours (P=0.0004). Our results were consistent across subgroups of women based on age and ethnicity. We found few significant differences by histologic subtype, although the strongest protective effect of multiparity was seen for mixed ductolobular tumours. Our results indicate that parity and age at first birth are associated with reduced risk of receptor-positive tumours only, while lactation is associated with reduced risk of both receptor-positive and -negative tumours. This suggests that parity and lactation act through different mechanisms. This study also suggests that reproductive factors have similar protective effects on breast tumours of lobular and ductal origin.  相似文献   
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While data are accumulating on the efficacy of prophylactic mastectomy as a means to reduce breast cancer risk in high risk women, the effectiveness of the procedure depends on women's interest in undergoing the procedure. We report on women's responses to this surgical option as a prevention tool. Data derive from a multi-method study of women's interest in and understandings about genetic testing for breast cancer susceptibility. The sample comprises 246 women of varying ethnicities and familial breast cancer risk from Seattle, USA. In this paper, quantitative data are presented on the sociodemographic and risk perception correlates of degree of interest in taking a genetic test for breast cancer if prophylactic mastectomy were the only treatment option. In addition, we report results of a content analysis of women's open-ended responses to the question of whether and why they could imagine undergoing prophylactic mastectomy. Our analysis of these data benefits from a central distinction in medical anthropology between the concepts of illness and disease. We suggest that while prophylactic mastectomy may prevent the "disease" of breast cancer, it may be of little interest to women who see this surgery as itself mimicking the "illness" of breast cancer.  相似文献   
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BACKGROUND: There are known racial disparities in renal graft survival. Data are lacking comparing associations of race/ethnicity and socioeconomic status with graft failure and functional status after transplantation. Our goal was to test if African-American and Hispanic race/ethnicity and poverty are associated with worse outcomes following renal transplantation. METHODS: We performed a retrospective cohort study using a nationwide registry (United Network for Organ Sharing). We studied 4,471 adults who received renal transplants in 1990. Outcomes were graft failure and functional status over 10 years. RESULTS: Cumulative incidence of graft failure was higher among African-Americans and Hispanics than whites (77% vs. 64% vs. 60 %; P<0.001) and among transplant recipients living in the poorest areas (70% vs. 58% in the richest; P<0.001). African-American and Hispanic race/ethnicity were independently predictive of graft failure (RR 1.8, 95% CI 1.6-1.9; RR 1.3, 95% CI 1.2-1.6, respectively) in multivariate analyses but poverty status was not (RR 1.0, 95% CI 0.9-1.1). Days with impaired functional status were higher for African-Americans compared to whites (RR 1.6, 95% CI 1.3-1.9) but not independent of poverty. Poverty was independently associated with impaired functional status (RR 1.3, 95% CI 1.0-1.6). CONCLUSIONS: African-Americans and Hispanics had higher rates of graft failure compared to whites after adjustment for poverty and other covariates whereas poverty, but not race/ethnicity, was related to functional status following renal transplantation. National datasets should include individual-level measures of socioeconomic status in order to improve evaluation of social and environmental causes of disparities in renal transplant outcomes.  相似文献   
78.
Analysis of optokinetic and eye tracking data on normal subjects   总被引:1,自引:0,他引:1  
This study was undertaken to determine the incidence of abnormal eye tracking patterns in normal subjects and to compare the optokinetic (OPK) response of normal subjects using a nystagmographic gonioscope (Nystagmotrac) and Coats's type of OPK drum. Eye movement was recorded by means of an electronystagmographic (ENG) recorder, and the speed of the slow component was computed for the OPK response. The eye tracking test showed a high rate of abnormality among our subjects. Optokinetic testing revealed highly symmetrical responses for all subjects.  相似文献   
79.
Thoracic computed tomographic (CT) scans of 250 patients with newly diagnosed or recurrent lymphoma revealed thoracic wall involvement in 24 patients (11 with Hodgkin disease, 13 with non-Hodgkin lymphoma). Thoracic wall involvement occurred without contiguous mediastinal or parenchymal involvement in 17 patients. Of these, 13 patients had masses beneath the pectoralis muscles or within the breast, and four had masses arising from the ribs. Five additional patients had mediastinal masses with thymic involvement and parasternal extension through the thoracic wall. Pulmonary parenchymal lymphoma with thoracic wall invasion was noted in the remaining two patients. In five of nine patients receiving radiation therapy, treatment plans were modified by CT demonstration of thoracic wall lymphoma.  相似文献   
80.
Pseudotumor cerebri and hypothyroidism   总被引:2,自引:0,他引:2  
A 38-year-old obese woman with concurrent hypothyroidism and pseudotumor cerebri was monitored with serial thyroid function tests and CSF pressure determinations during levothyroxine sodium replacement therapy. Following normalization of the patient's thyroid status, assessed by both clinical and chemical indexes (serum thyroxine level, 1.5 to 11.0 micrograms/dL; serum thyrotropin level, 128 to 1.5 micro units/mL), intracranial hypertension persisted for more than four months. After weight loss, acetazolamide therapy, and intermittent CSF drainage failed to produce remission, glucocorticoid therapy was associated with prompt, sustained resolution of the pseudotumor cerebri. Contrary to previous reports, this patient's clinical course suggests that thyroid hormone deficiency and pseudotumor cerebri are not causally related.  相似文献   
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