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Difficulties and bonuses of evaluating injury prevention programmes are illustrated by reference to an evaluation of the New Zealand's Children's Nightclothes Act 1977. It is demonstrated that despite the difficulties encountered in that evaluation, and the equivocal results, there were significant bonuses which more than justified the resources devoted to the evaluation. The paper is presented in an attempt to encourage others to evaluate thermal injury countermeasures who may be hesitant to do so because of the difficulties they foresee.  相似文献   
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The effect of fulminant hepatic failure on protein C antigen and activity   总被引:1,自引:0,他引:1  
In eighteen patients with fulminant hepatic failure (FHF), in grade III or IV coma, both protein C antigen and activity were significantly decreased (0.35 +/- 0.03 u/ml and 0.35 +/- 0.03 u/ml respectively). There was a significant correlation between protein C antigen and activity (r = 0.61, p less than 0.01). Protein C antigen levels were inversely correlated with prothrombin time (r = -0.57, p less than 0.05) as were protein C activity levels (r = -0.57, p less than 0.05). There was also significant correlations between fibrinogen and protein C antigen (r = 0.69, p less than 0.01) and protein C activity (r = 0.61, p less than 0.01). These results demonstrate that the naturally occurring inhibitor of coagulation, protein C, is present at low levels in FHF and this is probably due to the lack of synthesis of the protein in the damaged liver. The low levels of protein C may make these patients more susceptible to the disseminated intravascular coagulation which is known to occur in FHF and this in turn will lead to a further reduction in protein C levels.  相似文献   
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The haemodynamics of the uterine arteries and myometrium were assessed using Doppler ultrasound in forty consecutive patients requiring treatment for invasive mole and choriocarcinoma. The investigations were performed prior to the commencement of chemotherapy and the subjects followed prospectively. The Doppler waveforms from the uterine arteries were analysed using the pulsatility index. It was found that patients with a pulsatility index of 1.1 or less were significantly more likely to develop drug resistance than those with a higher value (P < 0.04). There was no significant association between the pulsatility index and metastatic disease or uterine bleeding. Five out of eight patients who developed drug resistance could have avoided initial inadequate treatment if the Doppler findings were included in the scoring system for selecting chemotherapy for these tumours. It can be concluded that assessment of the uterine arteries using the pulsatility index prior to the treatment of patients with invasive mole and choriocarcinoma is of help in predicting those who will develop drug resistance.  相似文献   
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A controlled trial was carried out in 209 primary cadaveric renal transplants to compare the effects of cyclosporine and steroids (double therapy) with those of cyclosporine in lower initial dose, azathioprine, and steroids (triple therapy). Patients have been followed 1-36 months since transplantation. Actuarial two-year graft survival (double 74%, triple 76%) and two-year patient survival (double 90%, triple 93%) were similar for both groups. Further analysis of particular risk factors including age, diabetes, HLA matching, acute renal failure, and use of sequential Minnesota antilymphocyte globulin in patients with delayed graft function also showed similar outcomes with both immunosuppressive regimens. Initial hospitalization time, rate of rejection, incidence of serious infection, and rate of rehospitalization were not different. Mean CsA doses and mean trough whole-blood levels were higher in double-therapy patients at hospital discharge but not by three months posttransplant. There were no differences between the two groups in iothalamate clearance at any time. Hypertension was more frequent six months posttransplant in the triple-therapy group (p less than 0.05). Thus, similar results were obtained with both regimens, and except for hypertension no regimen appeared to have increased side effects up to three years posttransplant.  相似文献   
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Development of interventions to prevent accidental occupational fatalities requires the prior identification of those at risk and the circumstances surrounding the injuries. A survey of unintentional farm fatalities was conducted using medical examiner reports (RIME) and death certificates (MECD) to identify deaths due to agricultural occupational injuries in North Carolina from 1984 through 1988. Of 393 cases, 123 met the criteria "farmer" listed as occupation on the RIME/MECD and/or "victim" in a rural area performing a farming task when injured. A second aim of this study was to use an existing data base to achieve maximum accuracy in identifying true cases of work-related farm fatalities.
A fatality rate of 41/100,000 agricultural workers was found; the National Institutes of Occupational Safety and Health's National Traumatic Occupational Fatality study criteria would have identified only 57 percent of these. Victims were characterized as middle age (53 years), white (76%), male (100%), full-time farmers (65%). Injury occurred during harvest season on Monday or Tuesday (47%) between 2 and 6 p.m. (54%). Death was pronounced at the scene (74%), with probable cause listed as tractor (62%). Injury location and land elevation were also related, with the mountain region having twice the fatality rate as the coastal plains region.  相似文献   
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Measurements of plasma atrial natriuretic peptide concentrations at 8 AM showed raised levels in 21 patients with cirrhosis and ascites (10.5 +/- 0.8 pmol/L) compared with levels in 10 age-matched controls (4.1 +/- 0.64 pmol/L; p less than 0.0001). In eight patients and 10 controls, atrial natriuretic peptide, plasma renin activity, plasma aldosterone and urinary sodium excretion were measured every 4 hr for 24 hr. Subjects were mobile between 8 AM and 11 PM and supine from 11 PM to 8 AM. In controls, urinary sodium excretion was highest between 4 PM and 11 PM (19.34 +/- 3.74 mumol/min) and lowest between midnight and 8 AM (7.06 +/- 1.23 mumol/min; p less than 0.001). In patients, urinary sodium excretion was 0.63 +/- 0.14 mumol/min between 4 PM and midnight and 1.85 +/- 0.71 mumol/min (p less than 0.08) between midnight and 8 AM. In patients during the day, mean plasma atrial natriuretic peptide concentration did not change despite large individual variation, but large, sustained rises in plasma renin activity and plasma aldosterone were seen. Correlations were noted between atrial natriuretic peptide and urinary sodium excretion between midnight and 8 AM (r = 0.65; p less than 0.02) and 4 PM and midnight (r = 0.54; p less than 0.05) but not between 8 AM and 4 PM. Plasma renin activity dropped from 12.54 +/- 2.49 at midnight to 7.41 +/- 0.88 pmol/hr/ml at 8 AM (p less than 0.05); plasma aldosterone decreased from 1,032 +/- 101 to 798 +/- 56 pmol/L (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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