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81.
Conventional risk factors have very low predictive power in identifying haemodialysis patients at high risk of vascular accidents. A role for apolipoprotein E isotypes was looked for in a small, but rigorously defined, cohort of longterm haemodialysis patients. In individuals with high vascular risk, as identified by higher common carotid intima/media thickness, we found an excess of apolipoprotein E4 alleles. This preliminary result requires confirmation in large patient cohorts.   相似文献   
82.
OBJECTIVE: to assess whether the use of Safehip hip protectors would prevent second hip fractures among men and women living in the community. DESIGN: pragmatic randomised controlled trial. SETTING: people living in the community. PARTICIPANTS: men and women aged 70 years and over who had sustained one hip fracture and who were living in the community. RESULTS: 366 men and women who were either living outside residential care or were about to be discharged back home were randomised to receive three pairs of hip protectors or to act as controls. Approximately 34% of participants allocated to receive hip protectors wore them every day. After a median follow up of 14 months 8 participants had a second hip fracture with 6 in the intervention and 2 in the control group (Odds Ratio for second hip fracture=3.10, 95% confidence interval 0.62-15.58). Hip protectors had no effect on risk of other fractures or on falls. CONCLUSION: this trial does not suggest a benefit of the studied hip protector among people living outside residential accommodation.  相似文献   
83.
BACKGROUND: in 1997 the vascular surgeons across the North of England commenced a study to examine various aspects of the management of lower limb occlusive arterial disease (LLOAD). Two aspects of this work were to assess workloads between hospitals and develop guideline parameters for managing intermittent claudication (IC) and critical limb ischaemia (CLI). The guidelines were to be developed, tested and modified by this study. METHOD: prospective inclusion of all patients admitted for investigation of LLOAD to nine hospitals by 19 surgeons over a period of 12 months. RESULTS: the hospitals admitted an average of 106 legs per 100 000 population (range 53-149) with LLOAD. Legs with IC (n=1351) were revascularised slightly less frequently than predicted (actual 76%, guideline 80%) and radiological treatment was used more frequently than predicted (radiology/surgery, actual 69/32%, guideline 40/60%). For limbs with CLI, revascularisation was undertaken more often (actual 70%, guideline 60%) and radiological intervention used more frequently (radiology/surgery, actual 45/58%, guideline 35/65%) than anticipated. Primary amputation, overall mortality and limb salvage were better than the predicted guidelines. CONCLUSION: large variations in workloads and clinical practice were observed between hospitals for the management of LLOAD. Developing guidelines for the management of limbs with IC was not considered appropriate, whereas suitable guidelines for legs with CLI were developed, tested and modified.  相似文献   
84.
Breast cancer among women given X-ray therapy for acute postpartum mastitis   总被引:3,自引:0,他引:3  
Acute postpartum mastitis (APM) is an inflammatory-infectious condition of the breast, occurring commonly at childbirth or during lactation. A series of 601 women who received x-ray therapy for APM during the 1940's or 1950's have been followed up by mail questionnaire, with medical verification of pertinent conditions, to ascertain their incidences of breast cancer. Control subjects consisted of a series with APM who did not receive irradiation, plus the female siblings of both the APM groups, for a total of 1,239 controls. The groups have been followed up to 45 years; the average was 29 years. The relative risk (RR) for breast cancer, adjusted for age and interval since irradiation (or an equivalent entry definition for controls), was 3.2 for the irradiated breasts; the 90% confidence interval (CI) was 2.3-4.3. For a linear multiplicative model, the risk increased by 0.4% per rad (90% Cl of 0.2-0.7). The dose-response curve appeared to be essentially linear, except for a diminution of risk at high doses (greater than or equal to 700 rad). The fact that there were no treated breasts with doses between 0 and 60 rad, however, means that it was not possible to evaluate the curvature with the maximum contrast between low and high doses. The dose fractionation analyses showed that neither the number of dose fractions, the number of days between fractions, nor the dose per fraction had any apparent effect on breast cancer risk when the variables were analyzed separately. Similarly, when the fractionation variables were considered jointly in a Cox regression analysis, none was significant once total breast dose was controlled for. Analyses of age at irradiation did not show appreciable differences between age groups, although the numbers were too small to be clear-cut (only 64 women greater than 34 yr old at irradiation). Other studies have shown diminished risk associated with an older age at irradiation. The lack of diminished risk in this study may occur because during pregnancy and lactation the breasts are under increased proliferative stimulation by hormones, by comparison with the normal condition of breasts at older ages. An analysis of the temporal relationship of radiation to breast cancer showed that the RR did not vary systematically with interval since irradiation, but the absolute risk increased over time. This finding agrees with other studies that have also suggested a better fit for the multiplicative model.  相似文献   
85.
新缩瞳剂包公藤甲素人工合成研究   总被引:11,自引:0,他引:11  
包公藤甲素是从包公藤(Erycibe obtusifolia Benth.)茎中提得的一个新莨菪烷生物碱,具有强烈的缩瞳作用,临床用于治疗青光眼。本文报道用合成的6β-乙酰氧基托品酮为原料,经卤代、水解、还原和N-去甲基化等反应合成包甲素(8)。经光谱测定证实8与天然包甲素的结构完全一致。合成品系外消旋体,其作用机理与天然品相同,而强度则减半。  相似文献   
86.
87.
Nutritional support is provided to children after severe burn injuries in amounts derived from empirical formulas or measurements of resting energy expenditure. To scrutinize these methods, indirect calorimetry measurements were performed on 74 survivors of burns (greater than or equal to 40% total body surface area) and compared to their actual caloric intake, percent weight change, and optimal caloric requirements formulated from the Curreri and Shriners' equations. These parameters showed that in spite of an initial deficit in actual caloric intake as compared to formulated goals, weight was maintained, whereas resting energy expenditures ranged from 30% to 40% below the actual caloric intake. Furthermore, a subgroup of patients (n = 42) who met +/- 20% of their formulated needs were stratified by extent of burn; this illustrated a significant weight gain in the more severely burned children. In conclusion, nutritional formulas in popular use overestimate caloric requirements in severe burns, whereas resting energy expenditure measurements require an additional factor of 30% to maintain body weight.  相似文献   
88.
Huntington disease (HD) is caused by an expanded CAG repeat sequence in the HD gene. Although the age at onset is correlated to the CAG repeat length, this correlation only explains approximately half of the variation in onset age. Less variation between siblings indicates that the variation is, in part, explained by genetic modifiers. We analyzed polymorphic loci within or close to the HD gene on the HD chromosome in Danish HD patients. We found one specific haplotype segregating with later age at onset, compared with patients with similar CAG repeat length and another haplotype. The nine Danish families in the study carrying this haplotype most likely have a common founder. Several of the polymorphic loci displayed alleles that may be specific to the late-onset haplotype, implicating that from this study we cannot determine which of the loci tested (or other polymorphic loci in this chromosomal area) do in fact contain genetic modifiers of age at onset.  相似文献   
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