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1.

Background  

Different interventions can reduce the burden of the chronic low back pain. One example is the use of a 'Back School Programme'. This is a brief therapy that uses a health education method to empower participants through a procedure of assessment, education and skill development. This study aimed to evaluate to what extent the programme could improve quality of life in those who suffer from the condition.  相似文献   
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Abstract –  The aims of this study were to investigate the incidence of coronal fracture of the anterior teeth in North Jordanian schoolchildren and to study the main predisposing factors and the factors that may affect the severity of this fracture. A study group (958) comprising schoolchildren aged 13–15 years was chosen by a simple random method from five geographical areas in Irbid Governate, Jordan. All children completed a questionnaire related to history of trauma to their anterior teeth before they had a clinical examination for lip competence, lip line and amount of fracture. Overjet was recorded from a study cast made for each student. Statistical analysis was performed using chi-square test. The results showed a prevalence of 11% of coronal fracture with female-male ratio of 1:1. An increase in the overjet more than 3 mm doubled the incidence of coronal fracture while overjet more than 6 mm increased the incidence fourfold. There was higher incidence of coronal fracture associated with lip incompetence and low lip line ( P  < 0.01). The severity of fracture increased in children with a larger overjet ( P  < 0.001). It was concluded that overjet, lip competence and lip line were important predisposing factors to coronal fracture of the anterior teeth while the severity of the fracture was mainly determined by overjet.  相似文献   
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AIM--To assess levels of some biochemical variables in sickle cell disease patients from eastern Saudi Arabia during steady state and in crises states, with a view to comparing biochemical and clinical manifestations of the disease with those in other geographical locations. METHODS--Serum calcium, uric acid, total bilirubin, lactate dehydrogenase, hydroxybutyrate dehydrogenase, and haemoglobin were measured in 110 sickle cell patients when in steady state. The same variables were measured on 30 of the patients when they went into crisis. RESULTS--Serum calcium tended to be lower in sickle cell patients than in healthy controls, while uric acid tended to be in the high normal range. Crises did not make any difference to serum calcium but they increased the uric acid level significantly. All the other variables measured were significantly abnormal and more so during crises. CONCLUSIONS--Although the abnormal levels obtained for these biochemical variables in patients with sickle cell disease from eastern Saudi Arabia were similar to those from other geographical locations, there were noticeable differences in the severity of the abnormalities, which probably explains the differences in the clinical manifestations of the disease between geographical locations. Values of some of these variables could be adapted for use to monitor crises.  相似文献   
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Brain tissue exhibits viscoelastic behaviour. If loading times are substantially short, static tests are not sufficient to determine the complete viscoelastic behaviour of the material, and dynamic test methods are more appropriate. The concept of complex modulus of elasticity is a powerful tool for characterizing the frequency domain behaviour of viscoelastic materials. On the other hand, it is well known that classical viscoelastic models can be generalized by means of fractional calculus to describe more complex viscoelastic behaviour of materials. In this paper, the fractional Zener model is investigated in order to describe the dynamic behaviour of brain tissue. The model is fitted to experimental data of oscillatory shear tests of bovine brain tissue to verify its behaviour and to obtain the material parameters.  相似文献   
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Summary Insulin autoantibodies (IAAs) are associated with type I diabetes mellitus (DM) and have been suggested as predictive markers of the disease. Using an ELISA assay, we have studied the prevalence of binding to human insulin in sera from an Arab type I DM population and compared it with the prevalence in the family members (FMs) of the probands, in type II DM patients from the same population, and in Arab control subjects. Significant levels of binding occurred in 11/16 (69%) of type I DM patients and in 21/34 (62%) of their FMs, but in only 5/31 (16%) of type II DM patients and in 1/25 (4%) of control subjects. Within families, there was homogeneity with regard to the level of insulin binding and the mean family levels correlated with those of the proband (r=0.68, df=7, p=0.05). HLA-DR3 or -DR4 antigens occurred in 55/63 (87%) of type I DM patients and in 95/118 (81%) of their FMs. This was significantly higher (p<0.001) than in either type II DM patients (39/75, 52%) or in control subjects (34/93, 37%). ICAs were present in significantly more (25/43, 58%) of type I DM patients than their FMs (3/82, 3%) (p<0.001). They did not occur in either type II DM patients or in the control group. In conclusion, insulin binding occurred in sera from both type I diabetic patients and their kindred, and hence did not appear to be specifically associated with the development of clinical diabetes.  相似文献   
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Fatty acid composition of ovules (ovulated oocytes) from kutum (Rutilus frisii kutum) was investigated to assess their relationship to gonad biological characteristics, larval size, fertilization, and hatching success. Forty-eight kutum were captured in the wild during the spawning season. Results revealed an inverse relationship between linoleic acid (18:2n-6) and ovule weight (P?<?0.05). Arachidonic acid (20:4n-6) and eicosapentaenoic acid (20:5n-3) contents showed a direct correlation with the number of ovules per gram (P?<?0.05); the latter had an inverse relationship with the ratio of surface to volume (P?<?0.01). There was a direct and significant correlation between docosahexaenoic acid (22:6n-3) and ovule weight (P?<?0.05). High unsaturated fatty acid levels indicated a direct relationship with egg and yolk diameters and also an inverse correlation with ovule surface to volume ratio (P?<?0.l05). Direct relationships were found between polyunsaturated fatty acids and the diameter of egg and yolk as well as the ratio of surface to volume (P?<?0.05). There was a direct correlation between saturated fatty acid content and the number of eggs (per gram) (P?<?0.01). Total lipid and weight of newly hatched larvae represented a direct relationship (P?<?0.05). Despite living in brackish water and migrating to fresh water during the reproductive season, kutum exhibited greater similarity in ovule fatty acid composition to saltwater fish than species in fresh water. Moreover, with respect to biological characteristics, this species shows more significant relationships with n-3 fatty acids than with n-6 fatty acids.  相似文献   
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