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101.
BACKGROUND: Hip dislocation in children with cerebral palsy has a well-documented history and morbidity. OBJECTIVE: This paper presents a retrospective study of children with bilateral cerebral palsy who had various postural management and its effect on hip deformity. The most widely accepted theoretical model of hip subluxation/dislocation is that an imbalance in muscle length and strength around the hip leads to acetabular dysplasia and consequent hip subluxation. Maintenance of muscle length and strength and loadbearing is therefore a logical prevention. Research on normal infants' postures has provided biomechanical data to form the theoretical basis of 24 h postural management equipment. METHODS: The notes and X-rays of 59 children with bilateral cerebral palsy from East and West Sussex and Oxfordshire were examined and measured to determine whether a relationship existed between postural management and the level of hip subluxation/dislocation. X-rays were measured using Reimers' hip migration percentage. Postural management support was divided into three groups for analysis. Category 1: use of a 24-h postural management approach using Chailey Adjustable Postural Support (CAPS) systems in lying, sitting and standing; category 2: two items of CAPS (either lying/sitting or sitting/standing supports); category 3: use of the CAPS seat only and/or any other postural supports. Hip status was recorded for analysis as both hips safe (under 33% migrated), or one/both hips subluxed. RESULTS: Children using 'All CAPS' before hip subluxation maintained significantly more hip integrity than other groups (chi2 P < 0.05). CONCLUSIONS: Postural management interventions have an important role in the prevention of hip dysplasia. 相似文献
102.
Steyermark AC Lam MM Diamond J 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(13):8754-8759
Quantitative evolutionary design involves the numerical relationships, evolved through natural selection, of biological capacities to each other and to natural loads. Here we study the relation of nutrient-processing capacities of the intestine and of organs beyond it (such as liver and kidneys) to each other and to natural loads of nutrients normally consumed. To control experimentally the rate of nutrient delivery to organs beyond the intestine, we administered nutrients directly into the veins of rats by the method of total parenteral nutrition (TPN). Control rats consuming the TPN solution by mouth ingested glucose at 42 mmol/day and processed it completely, as gauged by negligible appearance of glucose in urine and feces. Experimental rats receiving TPN were able to process infused glucose completely at rates up to 92 mmol/day. At higher infusion rates, they were unable to process further glucose, as gauged by rises in serum and urinary glucose levels and serum osmolality. At the highest infusion rates, they exhibited diuresis, dehydration, and both decreased weight gain and survival. These symptoms closely resemble the human diabetic condition known as nonketotic hypertonicity. Thus, a rat's body has a safety factor of 2.2 (=92/42) for glucose processing: it can process glucose at a rate 2.2 times its voluntary intake. This safety factor represents apparent excess capacity that may have evolved to process other nutrients converted into glucose, to minimize the risk of loads swamping capacities, to handle suddenly increased nutrient requirements, or to effect rapid mobilization of glucose. 相似文献
103.
Moayyedi P Wardman M Toner J Ryan M Duffett S 《European journal of gastroenterology & hepatology》2002,14(4):429-433
OBJECTIVE: The Department of Health states that patients with suspected cancer should be seen within 2 weeks, and the Patients' Charter suggests that patients should not wait for more than 30 min in outpatients. Decisions such as these are often made with little assessment of patient preferences. We have elicited patient preferences for the optimal use of time in the outpatient clinic. DESIGN: Questionnaire survey eliciting preference between different clinic scenarios evaluated using discrete choice conjoint analysis. SETTING AND PARTICIPANTS: Patients attending a teaching hospital gastroenterology outpatient clinic. MAIN OUTCOME MEASURES: The relative importance of time spent on the waiting list, time waiting in the clinic, time spent with the specialist, and time waiting for investigation was assessed using a logit model. RESULTS: Patients placed a similar value on waiting for investigation and time spent on the waiting list. A clinic that had a 2-month waiting list but offered immediate investigations would therefore be more popular than a clinic that had a 2-week waiting list but whose investigations were deferred for 3 months. Patients would be prepared to spend an extra 30 min in the waiting room if they spent 1 month less on the waiting list or waiting for investigation. Time spent with a specialist is valued, and patients would be prepared to spend an extra 3 min waiting in the clinic for every extra minute spent with the doctor. CONCLUSIONS: The present Department of Health recommendations and the Patients' Charter are too simplistic and do not take into account patient preferences. 相似文献
104.
Dose-finding and pharmacokinetic study of cisplatin, gemcitabine, and SU5416 in patients with solid tumors. 总被引:19,自引:0,他引:19
Bart C Kuenen Lee Rosen Egbert F Smit Mandy R N Parson Marcel Levi Rita Ruijter Holger Huisman Marc A Kedde Paul Noordhuis Wim J F van der Vijgh Godefridus J Peters Gillian F Cropp Paul Scigalla Klaus Hoekman Herbert M Pinedo Giuseppe Giaccone 《Journal of clinical oncology》2002,20(6):1657-1667
PURPOSE: To investigate the feasibility and pharmacokinetics of the combination cisplatin, gemcitabine, and SU5416. PATIENTS AND METHODS: Patients received cisplatin 80 mg/m(2) on day 1, gemcitabine 1,250 mg/m(2) on days 1 and 8, repeated every 3 weeks, and SU5416 (85 and 145 mg/m(2)) intravenously twice weekly. Pharmacokinetics of all three agents, side effects, and antitumor response were investigated in patients with solid tumors amenable to therapy with cisplatin/gemcitabine. RESULTS: In the first cohort of three patients entered at the 85 mg/m(2) dose, no dose-limiting toxicities were observed. In the next cohort (145 mg/m(2)), three patients developed a thromboembolic event. After entry was restricted to patients with low thromboembolic risk, three additional patients enrolled at 145 mg/m(2) developed a thromboembolic event. The dose was then reduced to 85 mg/m(2) in all patients still on the study, and three additional patients were entered on this dose level. In 19 treated patients, eight patients developed nine thromboembolic events (three transient ischemic attacks, two cerebrovascular accidents, and four deep venous thromboses). The most common toxicities observed were those previously reported for SU5416 alone (headache and phlebitis) and for this chemotherapy regimen (nausea, thrombocytopenia, and leucopenia). No significant pharmacologic interaction among the three drugs was observed. Response rates were similar to those expected in the patient population selected for this study. Analysis of variables of the coagulation cascade and of vessel wall activation was performed in three patients and showed significant increases in thrombin generation and endothelial cell perturbation in a treatment cycle-dependent manner. CONCLUSION: The incidence of thromboembolic events, possibly related to the particular regimen tested in this study, discourages further investigation of this regimen. 相似文献
105.
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107.
Individuals' rationality has been a key issue long debated in Economics. While normative theories establish the way 'rational' consumers should behave, many empirical studies have documented numerous systematic violations of normative principles. This has led some to question the validity of classic economic models as an adequate approximation of individuals' real decision-making. This paper aims to shed more light on this debate. A stated preference choice experiment was set up to test rational choice properties. Attention was given to the extent to which satisfaction of such tests is related to both the complexity of the design, and subject characteristics. Quantitative and qualitative methods are applied. The majority of respondents passed the rationality tests. Satisfaction of the tests was sensitive to normatively irrelevant factors such as the complexity of the task and demographic characteristics. A significant proportion of those individuals who 'failed' seem to have reformulated the experiment in some way in their mental process. Implications for the design and analyses of future DCEs are discussed. 相似文献
108.
The authors wished to assess medical students' attitudes towards communication skills learning, and to validate the use of the Communication Skills Attitude Scale (CSAS) in a different population. This cross-sectional study of Years 1-3 MBChB students, University of Aberdeen, in 2002-03 (overall response rate=86.2%) identified significant differences in attitudes to communication skills teaching by year of study and gender. PAS (positive attitudes scores) for Year 1 were significantly higher than those for Years 2 and 3. NAS (negative attitudes scores) for Year 1 were significantly lower than the scores for Year 2 but not Year 3. The scores for Years 2 and 3 were not significantly different. Female students had a significantly higher mean PAS score and lower mean NAS score than males, and were more likely to disagree that their communication and clinical skills were competent. While cohort effects may be present, it seems that attitudes towards communication skills learning are positive initially, becoming less so until students experience interacting with patients. Differences between male and female students reflect those seen in previous studies. The findings presented support the use of the CSAS as an appropriate tool to measure attitudes in a wide population of medical students. 相似文献
109.
Nutritional correlates of dietary glycaemic index: new aspects from a population perspective 总被引:1,自引:0,他引:1
Schulz M Liese AD Mayer-Davis EJ D'Agostino RB Fang F Sparks KC Wolever TM 《The British journal of nutrition》2005,94(3):397-406
The role of dietary glycaemic index (GI) and glycaemic load (GL) in disease aetiology is of increasing interest. However, nutritional factors related to dietary GI and GL are not well understood from a population perspective. We aimed to investigate the relation ship between GI and GL and dietary intake at the food and nutrient level. Study subjects were 1071 non-diabetic adults from the Insulin Resistance Atherosclerosis Study, Exam I, 1992-4. Usual dietary intake was assessed with a 114-item modified Block food frequency questionnaire. Published GI values were assigned to food line items. Correlation and regression analyses were conducted. Intake of white bread, beer, meats and fries/fried potatoes was positively associated with average GI, as was fat, starch and alcohol intake (before and after energy adjustment). Intake of fruits and low-fat milk was inversely associated with GI, as were intakes of mono- and disaccharides, and fibre. GL was positively correlated with carbohydrate foods and inversely with non-carbohydrate foods. Gender-specific regression models identified eight food groups explaining 63% (men) and 55% (women) total GI variation after adjusting for demographics; 70% of variation in GL was explained by eleven (men) and nine (women) food groups, respectively. Although the GI of a food is an indicator of the ability of carbohydrates to raise blood glucose, dietary GI, unlike GL, appears to reflect more dimensions of diet than just carbohydrates, such as the combination of foods consumed. This may have implications for the interpretation of dietary GI in epidemiologic studies. 相似文献
110.