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41.
A review of smoking habits of 77 vascular related amputees demonstrated a high incidence of smoking significantly greater for men than in the general population. Male smoking amputees with atherosclerosis related peripheral vascular disease were found to have a high risk of having an above-knee amputation. Those with diabetes mellitus whether male or female, smokers or not, had a significantly greater chance of having a below-knee amputation. Overall, non-smokers were found more likely to have a below-knee amputation than an above-knee (p less than 0.05).  相似文献   
42.
The authors review the natural occurrence of tumour dormancy in man and animal models, which show the importance of cellular defence mechanisms in inducing and maintaining the state of tumour dormancy. Six cases of non-small-cell lung cancer are described. The patients exhibited moderate to very strong delayed hypersensitivity reactions to soluble lung-cancer antigen after specific immunotherapy. Three patients had nonregional metastases at 11, 12 and 14 years. Two had regional recurrence after 9 years, and in one patient a small hilar-node metastasis was found at autopsy after 7.6 years. In each case an immunodepressive event or drug treatment preceded resurgent growth. The effect of renal transplantation in patients with a history of surgery for cancer supports the conclusion that cellular defence mechanisms are crucial for the maintenance of tumour dormancy in man.  相似文献   
43.
We have investigated the structural and histochemical features of the blood-brain barrier (b-bb) in both adults and embryos of chicken (Gallus domesticus, White Leghorn) and quail (Corturnix coturnix japonica). We found that brain endothelial cells of both species are characterized structurally by tight junctions, a low density of pinocytotic vesicles, and a moderately elevated density of mitochondria. Both alkaline phosphatase and butyryl cholinesterase were found in adult quail brain capillaries, but only alkaline phosphatase was found in adult chick brain capillaries. Aromatic amino acid decarboxylase was not found in brain capillaries of either species. In the chick embryo alkaline phsophatase appeared during the time when b-bb matures functionally; i.e., during the third week of development. However, an elevation in mitochondrial density was not apparent until after hatching. In the quail, alkaline phosphatase and butyrl cholinesterase appeared during the last week of embryonic development. By 2 days posthatching the structural characteristics of the brain capillaries were similar to those in the adult.  相似文献   
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Mini-Mental State Examination (MMSE) scores were studied in an ambulatory elderly population to identify correlates with self-reported signs, symptoms, diseases, drugs and laboratory values. A total of 1,264 subjects were studied including 844 women and 420 men. In this study, 5.0% of men and 5.3% of women scored less than 24 on the MMSE. A linear-regression model revealed eleven factors of significance in predicting scores on the MMSE. The most important predictors were age (p less than 0.0001), self-reported memory loss (p less than 0.0001), complaints of swollen feet or ankles (p less than 0.0010), the total number of diseases reported (0.0006) and the serum lactate dehydrogenase concentration (p less than 0.0098). Results suggest that cognitive function in the elderly is not related to the general level of health or consistently affected by specific disease states.  相似文献   
46.
Nitric oxide (NO), originally identified as the mediator of endothelial-dependent relaxation of vascular smooth muscle, is now known to also have cytotoxic effects under certain conditions. Thus, we have investigated the effects of inhibition of NO synthesis on ischemia/reperfusion injury in the rabbit rectus femoris muscle. Three and a half hours of ischemia and 24 hours of reperfusion resulted in a 56% loss of viability. In muscles receiving an infusion of the nitric oxide synthase inhibitor, L-NIO (30 μM), the loss of viability was reduced to 15%. Post-ischemic blood flow was increased in muscles receiving a saline infusion, whereas there was a marked decrease in blood flow for at least the first 60 minutes of reperfusion in muscles treated with L-NIO (30 μM). The increase in myeloperoxidase levels (indicative of neutrophil accumulation) following 24 hours of reperfusion was attenuated with L-NIO infusion by approximately 50% and the reperfusion-induced edema was also attenuated in L-NIO treated muscle. These findings suggest that endogenous NO production during ischemia/reperfusion injury may be deleterious to muscle survival. © 1994 Wiley-Liss, Inc.  相似文献   
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We describe the functioning and well-being of patients with depression, relative to patients with chronic medical conditions or no chronic conditions. Data are from 11,242 outpatients in three health care provision systems in three US sites. Patients with either current depressive disorder or depressive symptoms in the absence of disorder tended to have worse physical, social, and role functioning, worse perceived current health, and greater bodily pain than did patients with no chronic conditions. The poor functioning uniquely associated with depressive symptoms, with or without depressive disorder, was comparable with or worse than that uniquely associated with eight major chronic medical conditions. For example, the unique association of days in bed with depressive symptoms was significantly greater than the comparable association with hypertension, diabetes, and arthritis. Depression and chronic medical conditions had unique and additive effects on patient functioning.  相似文献   
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Native American, Hispanic, and Anglo sixth graders reacting to an example of teenage problem drinking expressed similar beliefs and attitudes in many respects. However, Native American children viewed the problem as less serious, subscribed more to a disease theory of alcoholism, attributed less causal responsibility to the individual, and adopted a less aggressive approach toward treatment than did Hispanic, and especially Anglo, children. Their less conventional value orientations accounted for all these differences except their stronger endorsement of a disease theory of problem drinking.  相似文献   
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