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51.
The value of cancer treatment was assessed using a natural experiment where patients who refused treatment served as no-treatment controls in a situation where withholding treatment to form a control group is unethical. Each cancer patient who refused treatment in Alberta, Canada between 1975 and 1988 was compared with five subjects who accepted treatment, matched on cancer site, age, number of cancers, and time period. Variables associated with treatment-refusal were included in Cox's proportional hazards model of survival, with death from cancer as the endpoint and deaths from other causes as censored observations. Treatment was refused at a rate of 7.5 per 1,000. One-third of patients who refused treatment had lung cancer and most had unstaged disease. Treatment refusal was associated with a difference in median survival of approximately nine months. Site-specific analyses showed a range of effects. Case fatality among the treated patients fell by approximately 10 percent during the 14-year study period. Even in advanced disease, treatment can result in improved survival. However, the results of this study must be interpreted with caution and cannot be generalized to all cancer patients.Dr Huchcroft and Mr Snodgrass are with the Alberta Cancer Board, Calgary, Alberta, Canada. Address correspondence to Dr Shirley Huchcroft, Senior Scientist, Division of Epidemiology and Preventive Oncology, Alberta Cancer Board, Calgary, Alberta, Canada T2N 4N2.  相似文献   
52.
53.
All cardiac surgical patients, emergency and routine, from the South West peninsula of England had to travel long distances until 19 months ago, a stressful if not dangerous situation. This paper describes the planning, commissioning and start-up of a brand new cardiac surgical facility. The lessons learnt may help similar projects as provision of specialist health care decentralizes.  相似文献   
54.
Cordyceps sinensis (CS) is a traditional Chinese medicine with immunomodulatory effect and is effective in improving the survival of lupus mice. In the present study we isolated a pure compound (H1-A) from CS and investigated its effect on inhibiting autoimmune disease progression in MRL Ipr/Ipr mice. Our results demonstrated that MRL Ipr/Ipr mice treated daily with H1-A (40 microg/kg/d orally) for 8 weeks had a progressive reduction in anti-ds-DNA production (optical density value decreased from 0.172 +/- 0.009 to 0.112 +/- 0.015) when compared with the control group (optical density value increased from 0.141 +/- 0.036 to 0.198 +/- 0.047). In clinical presentation, the treated group had a reduction in lymphadenopathy, a delayed progression of proteinuria, and an improvement in kidney function. Histologic analysis of kidney tissue indicated that H 1-A could inhibit the mesangial proliferation that was evident in lupus nephritis. However, there was no significant change in immune complex deposition. The studies reveal that the pure compound (H1-A) may be potentially useful for treating systemic lupus erythematosus in human patients, and they provide some questions for further investigation of the pathogenesis of systemic lupus erythematosus and lupus nephritis.  相似文献   
55.
PURPOSE: The purpose of this study was to investigate the effect of antioxidant on exercise-induced apoptosis in rat thymocytes. METHODS: After exercise at 13.8 m x min(-1) for 60-90 min x d(-1) on a motor-driven drum exerciser for 2 consecutive days, rat thymocyte apoptosis was monitored by the feature of DNA fragmentation. To study the effect of antioxidant, rats were administered with butylated hydroxyanisole (BHA) for 7 d before exercise. RESULTS: Exercise could induce thymocyte DNA fragmentation as detected on electrophoretic gel and by cell death detection ELISA kit. Further studies indicated that pretreatment with antioxidant BHA to rats resulted in a blockage of exercise-induced DNA fragmentation. The concentrations of glutathione (GSH) were not significantly changed in rat thymocytes after exercise with or without BHA treatment. CONCLUSION: These results suggest that reactive oxygen species may play a role in thymocyte apoptosis induced by exercise. However, changes in GSH levels were not observed in this exercise model.  相似文献   
56.
A 4-month-old boy with polydactyly and bifid epiglottis was found to have a large sellar and suprasellar mass. When the diagnosis of Pallister-Hall syndrome was made, conservative management was elected. When the patient was 2 years old, the tumor had grown proportionally with the patient, and he was developing appropriately. Although rare, this entity is important to recognize not only for clinical diagnosis but also for appropriate management and genetic counseling.  相似文献   
57.
The safety of cysteamine after renal transplantation and during pregnancy is an important issue, since girls with cystinosis are in better health on cysteamine therapy and thus more likely to become pregnant. In the first study, cysteamine was given to pregnant rats on days 6.5–18.5 post conception in oral doses of 0, 37.5, 75, 100, and 150 mg/kg per day. The dams were sacrificed on day 20.5, the fetal kidneys removed and prepared for histological examination. In the second study, cysteamine was given to dams on days 6.5–19.5 post conception in oral doses of 0, 37.5, 50, and 75 mg/kg per day. Dams were allowed to give birth naturally and pups were given cysteamine on days 4–21 to yield the same oral doses of cysteamine given to the dam. Renal function was evaluated on day 35. Histological examination of fetal kidneys revealed no changes even in kidneys from fetuses with growth retardation and malformations. Furthermore, there were no alterations in renal function in offspring on day 35. These findings demonstrate that cysteamine therapy does not affect renal development in the rat. Further investigations will be required to prove whether cysteamine therapy has the potential to affect renal development in the human. Received: 25 September 1998 / Revised: 17 November 1998 / Accepted: 13 December 1998  相似文献   
58.
The Dynamic Spatial Reconstructor (DSR) is a device constructed at the Biodynamics Research Unit of the Mayo Clinic for (among other things) the visualization of the beating heart inside the intact thorax. The device consists of 28 rotating X-ray sources arranged on a circular arc at 6° intervals (total span 162°) and a matching set of 28 imaging systems. The whole thorax of the patient is projected onto the two-dimensional screen of the imaging systems by cone beams of X rays from the sources. All of the X-ray sources are switched on and off within a total period of 10 milliseconds. The Medical Image Processing Group at the State University of New York at Buffalo has developed a software package for the design and evaluation of algorithms to be used by the DSR. In this paper we illustrate the operation of the package and a particular algorithm for the reconstruction of the dynamically changing structure of the heart from data collected by the DSR.  相似文献   
59.
Microbial O-carbamylation of novobiocin   总被引:2,自引:0,他引:2  
Novobiocin was inactivated by Streptomyces niveus US 2094 in fermentation. The inactivation product was isolated and characterized by NMR and MS as 2"-O-carbamylnovobiocin. The MICs of novobiocin and 2"-O-carbamylnovobiocin were determined for S. niveus strains.  相似文献   
60.
Doppler velocimetry of the umbilical and intraplacental fetal arteries was studied by color flow mapping in 39 normal pregnancies. The systolic-diastolic ratio (S/D) and pulsatility index of the intraplacental fetal artery downstream to the umbilical artery decreased significantly with advancing gestational age, and its S/Ds were persistently lower than those of the umbilical artery. The difference in the S/D between the umbilical artery and its intraplacental downstream branches decreased with advancing gestational age and approached zero as the pregnancy progressed to term. We conclude that intraplacental fetal arteries, possibly fetal arteries in main stem villi, can be imaged by color flow mapping and that there is a significant "resistance gradient" between the intraplacental fetal artery and the umbilical artery. Intraplacental fetal artery velocimetry using color flow mapping may give further insights into the umbilical-placental circulation.  相似文献   
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