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91.
It is of particular concern to evaluate the risk of lung cancer occurrence after breast cancer treatment as women with breast cancer quite often undergo radiation therapy as part of their initial treatment and their life expectancy remains long. From a roster of 7711 women initially treated for breast cancer between 1954 and 1984, a cohort-study was performed among 4171 1-year survivors followed during the period 1975-1995. The relationship between the radiation dose received by the lung and the risk of lung cancer was then evaluated in a nested case-control study of 11 breast-cancer patients who developed lung cancer and 22 controls matched for age at diagnosis of breast cancer, period of initial treatment and length of follow-up. Among the 4171 women, six developed lung cancer during the entire follow-up as compared to 5.4 cases expected (SIR = 1.1, 95% CI: 0.4-2.3). When considering only the women initially treated by radiotherapy with or without adjunction of chemotherapy and excluding the 10 first years of follow-up, the SIR was significantly increased (SIR = 3.2, 95%CI: 1.0-7.4). In the case-control study, nine of the 11 lung cancers occurred in the ipsilateral lung and two in the trachea. The overall odds ratio (OR) of lung cancer associated with initial radiotherapy was 1.4 (95% CI: 0.2-11.1) and an excess in the OR of 7% (90% CI: ? to 41%, p = 0.10) per gray delivered to the site of lung cancer was evidenced. Our results agree with previous studies in favor of an increased risk of lung cancer after radiation therapy for breast cancer.  相似文献   
92.
We evaluated breast cancer mortality through 1997 among 69 525 female radiologic technologists who were certified in the United States from 1926 through 1982 and who responded to our questionnaire. Risk of breast cancer mortality was examined according to work history and practices and was adjusted for known risk factors. Breast cancer mortality risk was highest among women who were first employed as radiologic technologists prior to 1940 (relative risk [RR] = 2.92, 95% confidence interval [CI] = 1.22 to 7.00) compared with risk of those first employed in 1960 or later and declined with more recent calendar year of first employment (P for trend =.002). Breast cancer mortality risk increased with increasing number of years of employment as a technologist prior to 1950 (P for trend =.018). However, risk was not associated with the total number of years a woman worked as a technologist. Technologists who first performed fluoroscopy (RR = 1.69, 95% CI = 1.02 to 3.11) and multifilm procedures (RR = 1.87, 95% CI = 1.04 to 3.34) before 1950 had statistically significantly elevated risks compared with technologists who first performed these procedures in 1960 or later. The high risks of breast cancer mortality for women exposed to occupational radiation prior to 1950 and the subsequent decline in risk are consistent with the dramatic reduction in recommended radiation exposure limits over time.  相似文献   
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Microglial cells, macrophage-lineage cells in the brain, are increased in amyloid-containing plaques in Alzheimer’s disease (AD) and in the lesions of prion diseases. Recent studies suggest that microglia have a central role in turnover of amyloid in these diseases. We report here that synthetic amyloid beta (Aβ) 1-42 and prion protein (PrP) 106-126 peptides promote macrophage survival; they also induce macrophage DNA synthesis, particularly in the presence of sub-optimal concentrations of the growth factor, macrophage-colony stimulating factor (M-CSF or CSF-1). These responses are proposed to provide a means to increase brain microglia/macrophage numbers thereby enhancing subsequent inflammatory/immune responses. These fibrillogenic peptides join the list of aggregates having these effects on macrophages, indicating the generality of this type of response.  相似文献   
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It was shown previously that luteinizing hormone-releasing hormone (LHRH) affects the neurohypophysial oxytocin release in water-deprived rats. However, the detailed mechanisms by which LHRH modifies the oxytocin response to hyperosmotic stimulation have not been explained so far. Using the isolated hypothalamo-neurohypophysial explants obtained from euhydrated rats, the effect of LHRH on the oxytocin secretion was studied under conditions of direct osmotic (i.e., Na(+)- evoked) as well as nonosmotic (i.e., K(+)-evoked) stimulation. Additionally, the oxytocin response to LHRH was investigated using the explants obtained from animals drinking 2% saline for eight days (systemic, i. e., both direct and indirect, osmotic stimulation). LHRH significantly enhanced Na(+)- and K(+)-evoked oxytocin release from explants taken from rats drinking tap water, indicating that LHRH could affect the Na(+)/K(+)-dependent depolarization of perikarya of oxytocin neurones. In contrast, LHRH significantly diminished the K(+)-stimulated hormone release when the neurohypophysial complex was obtained from previously salt-loaded rats, suggesting that peripheral osmotic stimulation somehow modifies the sensitivity of oxytocinergic neurones to LHRH (possible mechanisms are discussed). It is concluded that LHRH may participate in the regulation of oxytocin secretion via both direct and indirect impact on magnocellular oxytocinergic neurones depending on the current functional status of the hypothalamo-neurohypophysial complex.  相似文献   
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Background: Infants who suffer hypoxic‐ischaemic encephalopathy (HIE) at birth are at increased risk of developmental disability. In this at‐risk population, reliable, inexpensive and early identification of those children who are likely to require formal developmental assessment and intervention is needed. Aim: To evaluate the ability of the Ages and Stages Questionnaire (ASQ) to detect developmentally delayed children in an Australian population of infants who suffered HIE at birth. Methods: Fifty‐five children who survived HIE were followed until 12–14 months of age. Test characteristics were calculated to examine the ability of the ASQ to appropriately identify developmentally delayed infants against this study's ‘gold standard’: the Bayley Scales of Infant Development II. Results: Comparing the ASQ with the Bayley Scales of Infant Development II, the questionnaire had the following test characteristics: sensitivity 92%, specificity 95%, positive predictive value 92%, negative predictive value 95% when used to detect severe developmental delay; and sensitivity 67%, specificity 93%, positive predictive value 92%, negative predictive value 68% when used to detect both severe and mild developmental delay. However, the ASQ used at standard cut‐offs failed to detect any of the children with mild delay. Conclusions: The ASQ is extremely effective for the detection of severe developmental delay in children who have suffered HIE at birth. Its capacity to identify those with milder delay is limited. The ability of the test to detect only those with severe developmental delay means that the ASQ is of little value as a screening tool in this population.  相似文献   
99.
Summary The anticancer activity of carminomycin was investigated in a human tumor cloning assay. No efficacy could be identified in the WiDr and the MCF7 cell lines which were highly responsive to doxorubicin. In addition, drug testing experiments were carried out in samples of various malignancies freshly obtained from 86 patients of whom 54 had not received prior anthracyclines. A reduction in the number of tumor colony forming units by 50% or more was seen in 1/26 breast cancers, 1/22 ovarian cancers and 1/7 melanomas. Cross-resistance studies indicated that eight tumors were responsive to doxorubicin only and one to carminomycin only whereas two were sensitive to both and 73 were resistant to both. This in vitro Phase II study corroborates the disappointing clinical results achieved with carminomycin.  相似文献   
100.
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