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OBJECTIVE: To assess the frequency of risk factors for rhabdomyolysis with simvastatin and atorvastatin in cases reported to the Australian Adverse Drug Reactions Advisory Committee (ADRAC). DESIGN: Reports meeting the definition of rhabdomyolysis were reviewed for risk factors including age > or = 70 years, dose > or = 40 mg, hepatic dysfunction, diabetes mellitus, hyperkalaemia, hypothyroidism and the use of concomitant interacting medications. RESULTS: Only one report associated with simvastatin and five reports associated with atorvastatin did not list any risk factors for rhabdomyolysis. Interacting medicines featured in 77% of reports of rhabdomyolysis associated with simvastatin and 44% of reports associated with atorvastatin. A comparison of the age profile for reports of atorvastatin- and simvastatin-associated rhabdomyolysis with that for all adverse drug reaction reports received, and for all reports of muscle disorders, suggested a trend towards an increasing risk of rhabdomyolysis with increasing age with simvastatin but not with atorvastatin. Similarly, comparing prescribed tablet strengths from Pharmaceutical Benefits Scheme data with the HMG-CoA reductase inhibitor ('statin') doses in reports of rhabdomyolysis suggested a dose-related risk with simvastatin, but a less increased risk with high-dose atorvastatin. CONCLUSION: Risk factors for rhabdomyolysis featured in nearly all of the reports of statin-associated rhabdomyolysis and the majority of reports listed multiple risk factors, although dependence on risk factors appeared to be stronger with simvastatin than atorvastatin. The multiplication of risk factors in patients taking simvastatin and atorvastatin should be minimised.  相似文献   
994.
Head movement presents a continuing problem in PET studies. Head restraint minimizes movement but is unreliable, resulting in the need to develop alternative strategies. These include frame-by-frame (FBF) realignment or use of motion tracking (MT) during the scan to realign PET acquisition data. Here we present a comparative analysis of these 2 methods of motion correction. METHODS: Eight volunteers were examined at rest using (11)C-raclopride PET with the radioligand administered as a bolus followed by constant infusion to achieve steady state. Binding potential (BP) was estimated using the ratio method during 2 periods of the scan at steady state. Head movement was compensated by using coregistration between frames (FBF) and 3 methods using MT measurements of head position acquired with a commercially available optical tracking system. RESULTS: All methods of realignment improved test-retest reliability and noise characteristics of the raw data, with important consequences for the power to detect small changes in radiotracer binding, and the potential to reduce false-positive and false-negative results. MT methods were superior to FBF realignment using coregistration on some indices. CONCLUSION: Such methods have considerable potential to improve the reliability of PET data with important implications for the numbers of volunteers required to test hypotheses.  相似文献   
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Inorganic sling materials when used for treatment of urinary stress incontinence have a high success rate of achieving continence. They unfortunately attract the complication of vaginal tape erosion. When used for Transobturator tape procedure (TOT) we found the Obtape sling (Mentor-Porges, Le Plessis-Robinson, France) attracted a high rate of erosion, likely due to the tape properties. We describe a series of tape erosions with the Obtape sling, the presentation, conservative and surgical management with favourable rates of maintenance of continence. We suggest the use of larger pore sized tapes to decrease the occurrence of vaginal tape erosion.  相似文献   
997.
998.
BACKGROUND: Studies of the association between indoor allergen exposure and the development of allergic diseases have often measured allergen exposure at one point in time. OBJECTIVE: We investigated the variability of house dust mite (Der p 1, Der f 1) and cat (Fel d 1) allergen in Dutch homes over a period of 8 years. METHODS: Data were obtained in the Dutch PIAMA birth cohort study. Dust from the child's mattress, the parents' mattress and the living room floor was collected at four points in time, when the child was 3 months, 4, 6 and 8 years old. Dust samples were analysed for Der p 1, Der f 1 and Fel d 1 by sandwich enzyme immuno assay. RESULTS: Mite allergen concentrations for the child's mattress, the parents' mattress and the living room floor were moderately correlated between time-points. Agreement was better for cat allergen. For Der p 1 and Der f 1 on the child's mattress, the within-home variance was close to or smaller than the between-home variance in most cases. For Fel d 1, the within-home variance was almost always smaller than the between-home variance. Results were similar for allergen levels expressed per gram of dust and allergen levels expressed per square metre of the sampled surface. Variance ratios were smaller when samples were taken at shorter time intervals than at longer time intervals. CONCLUSION: Over a period of 4 years, mite and cat allergens measured in house dust are sufficiently stable to use single measurements with confidence in epidemiological studies. The within-home variance was larger when samples were taken 8 years apart so that over such long periods, repetition of sampling is recommended.  相似文献   
999.
BACKGROUND: Stress can aggravate the allergic inflammation, but determinants of disturbed immune regulation are largely unknown. OBJECTIVE: To determine systemic immunological, local inflammatory and functional airway responses to stress in healthy and atopic individuals. METHODS: Forty-one undergraduate students, 22 with allergy of whom 16 had asthma, and 19 healthy controls, were studied in a low-stress period and in association with a large exam. Subjects completed questionnaires on stress and health behaviours, underwent lung function tests, bronchial methacholine challenge, measurements of exhaled nitric oxide and urine cortisol. Blood cells were phenotyped, and cytokines from mononuclear blood cells were analysed. RESULTS: Perceived stress and anxiety increased in both groups during the exam period while cortisol increased only in the atopy group. Cytokine production decreased broadly in response to stress in both groups, which was paralleled by an increase in the proportion of regulatory T cells (CD4(+)CD45RO(+)CD25(bright)). Interestingly, atopic individuals, but not controls, reacted with a decreased T-helper type 1/T-helper type 2 (Th1/Th2) ratio and a decrease in natural killer (NK) cell numbers in response to stress. In control subjects only, exhaled nitric oxide decreased and forced expiratory volume in one second increased during stress. CONCLUSION: Atopic and non-atopic subjects shared some immune changes in response to stress, such as a dramatic decline in cytokines and an increase in the number of regulatory T cells in peripheral blood. However, other stress-induced immune changes were unique to atopic individuals, such as a skewed Th1/Th2 ratio and reduced NK cell numbers, indicating that some pathogenic mechanisms in atopics may be more strongly affected by stress than others.  相似文献   
1000.
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