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991.
J G Brody R Rudel N I Maxwell S R Swedis 《Public health reports (Washington, D.C. : 1974)》1996,111(6):494-507
Geographic patterns and time trends for breast cancer suggest there are preventable causes that may include environmental factors. This article describes the development of new methods used in the Cape Cod Breast Cancer and Environment Study to investigate whether synthetic chemicals in the environment contribute to breast cancer risk. 相似文献
992.
B F Trump T W Jones K A Elliget M W Smith P C Phelps A Maki I K Berezesky 《Renal failure》1990,12(3):183-191
Cellular toxicity and cellular carcinogenesis are closely linked. In the kidney, this relationship has been emphasized by the recent discovery of a number of putatively non-mutagenic chemicals that result in acute and chronic toxicity and ultimately in carcinogenesis, especially in the male rat. Many, but not all such compounds, result in renal PTE phagolysosomal overload. At the same time, known metabolites of other carcinogens, e.g., HCBD and FBPA, result in acute renal injury and/or necrosis, followed by chronic tubular disease, interstitial nephritis, and ultimately carcinogenesis. A series of cell mechanisms have been suggested that lead from acute cell injury to altered control of cell division. These mechanisms appear to involve ion deregulation, (especially [Ca2+]i) resulting from a variety of continued injuries, (e.g., oxidative stress from inflammatory cells) and ultimately leading to altered gene expression. 相似文献
993.
Acetylcholinesterase activity and pseudocholinesterase activity were examined in plasma and in striated muscles (whole heart and diaphragm muscles) of diabetic KK-CAy mice. Both activities of acetylcholinesterase in heart muscle and pseudocholinesterase in plasma were significantly increased in diabetic KK-CAy mice compared to pre-diabetic KK-CAy mice. Both acetylcholinesterase and pseudocholinesterase activities in skeletal muscle were not changed by the diabetic state. The increases in activity of plasma pseudocholinesterase was significantly correlated to the increase in blood glucose level in alloxan-, streptozotocin (STZ)-diabetic ddY mice and diabetic KK-CAy mice. The increase was not correlated to the body weight in non-diabetic female-KK-CAy mice. Furthermore, the activity of heart acetylcholinesterase was significantly correlated with the activity of plasma pseudocholinesterase (r = 0.79, P less than 0.01). The activities of acetylcholinesterases in heart muscles from STZ- and alloxan-diabetic ddY mice also tended to increase. The hypersensitivity of the pulse rate to a low dose (1 mg/kg) of acetylcholine was correlated to the activity of plasma pseudocholinesterase (r = -0.51, P less than 0.05). These results demonstrate that the activities of plasma pseudocholinesterase were increased by the diabetic state being associated with the increasing alteration of cardiac sensitivity to acetylcholine in the whole body. 相似文献
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A common misconception is held among many ethnic minoritiesin San Francisco that AIDS is exclusively a gay whitemale disease. This myth is false, but dangerous. To assistethnic minorities in understanding their risks for AIDS, successfuleducational programs for these populations must recognize thediversity within these communities, including their differingcultures, languages and religious backgrounds. San Franciscohas adopted a model that utilizes well-established and well-respectedcommunity-based organizations to provide the education and riskreduction programs. Utilizing these organizations allows foreducation of diverse populations that is culturally and linguisticallyrelevant, thus allowing San Francisco an opportunity to preventthe national minority AIDS statistics from occurring withinits boundaries. 相似文献
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