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991.
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Chronic exposure to tobacco smoke is known to impair mitochondrial function. However, the effect of acute tobacco smoke exposure (ATSE) in vivo, as might occur in social settings, on mitochondrial function and calcium handling of cardiac cells has not been examined. It was hypothesized that ATSE might adversely modify mitochondrial function as reflected in mitochondrial energetics, membrane potential, and calcium transport. Mitochondria were isolated from the hearts of adult rats either exposed to 6 h of environmental tobacco smoke ( approximately 60 mg/mm3 tobacco smoke particles) or sham exposure. To model a calcium stress similar to ischemia/reperfusion, mitochondria were exposed to a Ca2+ bolus with measurement of membrane potential, energetics, Ca2+uptake and release, and redox state. ATSE mitochondria were characterized by significantly higher ADP-stimulated ATP production and a more reduced redox state (NADH ratio) under basal conditions without observed changes in resting Psim. Exposure of ATSE mitochondria to Ca2+stress resulted in significantly more rapid depolarization of Psim. The initial rate of Ca2+uptake was not altered in ATSE mitochondria, but CsA-sensitive Ca2+ release was significantly increased. ATSE does not significantly alter resting mitochondrial function. However, ATSE modifies the response of cardiac mitochondria to calcium stress, resulting in a more rapid depolarization and subsequent release of Ca2+ via the mitochondrial permeability transition (MPT).  相似文献   
993.
Anal fistula in infants and children   总被引:1,自引:0,他引:1  
Conclusions Fistula-in-ano is not a rare affliction of infancy or childhood. In infants it is caused by infected anal glands but the mechanism is not the same as is the case in adults. Usually the cause is passage of frequent, soft stools or there are diarrheal episodes which traumatize the walls of the anorectal outlet which differ anatomically from those of adults. Diagnosis can be made easily and the treatment of choice is simple fistulotomy.  相似文献   
994.
A fungus originally described as a new species of Coelomomyces (C. milkoi) from larval Tabanidae in the Ukraine, USSR, is transferred to a new genus, Tabanomyces, and described in detail. The zygospores germinate to form a linear four-celled conidiophore, each cell producing a spherical conidium ejected as in Conidiobolus, thus confirming that the organism belongs in the Entomophthorales. The resemblance between the conidiophore of Tabanomyces milkoi and the basidium of the rusts supports the old concept that the rust fungi may be related to the Entomophthorales.  相似文献   
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1. The daily losses from the skin of Ca and Na have been measured for two healthy men. The losses included Ca and Na in exfoliated skin cells as well as in insensible perspiration. The daily output of Ca in urine was also measured.2. In five measurements, the total daily skin loss of Ca ranged from 8.0 to 21.1 mg with mean values of 16.7 and 10.8 mg for the two subjects. The total daily skin loss of Na under the same conditions ranged from 45 to 146 mg with mean values of 97 and 77 mg respectively.3. The ratio of the daily skin loss to the urinary excretion of Ca was 6.8 and 3.4%.4. There was no correlation between the daily skin loss of Ca and atmospheric humidity.5. In the last experiment, the fraction of the total skin loss of Ca due to fluid secretion was assessed by giving an I.V. dose of (47)Ca to each subject. The values derived for this fraction were 0.37 and 0.38.  相似文献   
998.
A cost increase of more than 900% for medical services to dialysis patients and transplant recipients has been projected during the decade 1974 to 1984. To evaluate the role of renal transplantation in the End-Stage Renal Disease Program, we analyzed direct costs and patient outcomes in 466 consecutive transplants at our center. A successful transplant from either a living related or cadaver donor cost less than +7,000 per year for two years of graft function. The cost of transplants rejected during the second year also proved cost-effective when compared with the yearly costs of maintenance-facility hemodialysis. Patient survival was 100% at two years for recipients of a transplant from a living related donor and 84% at two years for recipients of a transplant from a cadaver. Renal transplantation can reduce the rising costs for end-stage renal disease patient care, without reducing life expectancy.  相似文献   
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