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STUDY DESIGN: A double-blind, randomized controlled trial of a novel educational booklet compared with a traditional booklet for patients seeking treatment in primary care for acute or recurrent low back pain. OBJECTIVE: To test the impact of a novel educational booklet on patients' beliefs about back pain and functional outcome. SUMMARY OF BACKGROUND DATA: The information and advice that health professionals give to patients may be important in health care intervention, but there is little scientific evidence of their effectiveness. A novel patient educational booklet, The Back Book, has been developed to provide evidence-based information and advice consistent with current clinical guidelines. METHODS: One hundred sixty-two patients were given either the experimental booklet or a traditional booklet. The main outcomes studied were fear-avoidance beliefs about physical activity, beliefs about the inevitable consequences of back trouble, the Roland Disability Questionnaire, and visual analogue pain scales. Postal follow-up response at 1 year after initial treatment was 78%. RESULTS: Patients receiving the experimental booklet showed a statistically significant greater early improvement in beliefs which was maintained at 1 year. A greater proportion of patients with an initially high fear-avoidance beliefs score who received the experimental booklet had clinically important improvement in fear-avoidance beliefs about physical activity at 2 weeks, followed by a clinically important improvement in the Roland Disability Questionnaire score at 3 months. There was no effect on pain. CONCLUSION: This trial shows that carefully selected and presented information and advice about back pain can have a positive effect on patients' beliefs and clinical outcomes, and suggests that a study of clinically important effects in individual patients may provide further insights into the management of low back pain. 相似文献
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Z Zhao K A Koeplinger T Peterson R A Conradi P S Burton A Suarato R L Heinrikson A G Tomasselli 《Drug metabolism and disposition》1999,27(9):992-998
The mechanism of sulfonamide cleavage of PNU-109112, a potent HIV-1 protease inhibitor, by glutathione-S-transferase (GST) was investigated in the presence of reduced GSH. GST-catalyzed sulfonamide cleavage takes place via the nucleophilic attack of GSH on the pyridine moiety of the substrate with formation of the GS-para-CN-pyridinyl conjugate, the corresponding amine, and sulfur dioxide. Structure activity studies with a variety of sulfonamides indicate that an electrophilic center alpha to the sulfonyl group is required for cleavage. Substituents that withdraw electron density from the carbon atom alpha- to the sulfonyl group facilitate nucleophilic attack by the GS(-) thiolate bound to GST. The rate of sulfonamide cleavage is markedly affected by the nature of the electrophilic group; replacement of para-CN by para-CF(3) on the pyridine ring of PNU-109112 confers stability against sulfonamide cleavage. On the other hand, stability of sulfonamides is less dependent on the nature of the amine moiety. These principles can be applied to the synthesis of sulfonamides, labile toward cellular GST, that may serve as prodrugs for release of bioactive amines. Tumors are particularly attractive targets for these sulfonamide prodrugs as GST expression is significantly up-regulated in many cancer cells. Another potential application could be in organic synthesis, where protection of amines as the corresponding activated sulfonamides can be reversed by GST/GSH under mild conditions. 相似文献
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An analysis of variability in the stereotaxic position of five cerebral points in rats revealed:
- 1. (1) that variability was less from the bregma skull point than from ear-bar-zero or the lambda skull point,
- 2. (2) that high correlations exist between the position of skull points and cerebral structures, and
- 3. (3) that the use of two external landmarks for predicting the position of cerebral targets produces a greater than 40% reduction in errors over that resulting from the use of single (ear-bar-zero or skull landmark) predictors.
Keywords: Stereotaxic variability; Electrode placement; Rat 相似文献
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Seasonal temperature and power plant chlorination effects on estuarine invertebrates 总被引:1,自引:0,他引:1
Stuart L. Margrey Dennis T. Burton Lenwood W. Hall Jr. 《Archives of environmental contamination and toxicology》1981,10(6):691-703
The influence of seasonal temperatures (15–22°C) on chlorine (0.00, 0.15 and 0.30 mg/L total residual chlorine), T (2, 6 and 10°C), and exposure duration (0.08, 2.0 and 4.0 hr) interaction studies simulating power plant entrainment and effluent discharge conditions was evaluated for opossum shrimp,Neomysis americana and amphipods,Gammarus sp. Seasonal temperature was an important factor affecting the toxicity of the three treatment variables with both of these organisms. Mortality responses were greater at the higher acclimation temperatures. 相似文献
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O. F. Hutter F. L. Burton D. L. Bovell 《Journal of muscle research and cell motility》1991,12(6):585-589
Summary The tensile strength of the muscle fibre surface membrane was estimated (1) from the suction required to burst membrane patches and (2) by aspiration of sarcolemmal vesicles into micropipettes of uniform bore. Each method gave an average value close to 60 N cm–1 for the maximum tension sustainable by normal mouse sarcolemma and only slightly lower values for sarcolemma frommdx mice which lack dystrophin. The elastic modulus of area expansion, as measurable by pipette aspiration of sarcolemmal vesicles, was found to have an average value of 3160 N cm–1 for normal and 2770 N cm–1 formdx mouse sarcolemma.The tensile strength of the sarcolemma is much too small for any differences in it to be the basis for the different osmotic behaviour of normal andmdx muscle fibres reported recently (Menke & Jockusch, 1991). By analogy with the better understood origin of the osmotic fragility of different types of red blood cells, the higher osmotic fragility ofmdx muscle fibres is suggested to be of morphological origin. We postulate that dystrophin functions as an element of the submembrane cytoskeleton so as to maintain the normal folding which safeguards the sarcolemma against mechanical damage. 相似文献
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A A Halpern R Greene T Nichols D S Burton 《Clinical orthopaedics and related research》1979,(140):23-25
A compartment syndrome of the interosseous muscles can be a challenging diagnosis as there is generally no neurovascular compromise to the digits involved. The most sensitive clinical sign is pain with passive motion at the metacarpal phalangeal joint of the involved digit. In this report, a 31-year-old man developed a compartment syndrome of the first, second, and third dorsal interosseous muscles following an injection of heroin in the "snuffbox" area. Compartmental tissue pressure measurements were 80, 75, and 55 mmHg respectively, and were a significant aid in the early diagnosis as well as management. 相似文献