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Background  

The aims of this study were to examine the extent to which higher intellectual abilities protect higher socio-economic groups from functional decline and to examine whether the contribution of intellectual abilities is independent of childhood deprivation and low birth weight and other socio-economic and developmental factors in early life.  相似文献   
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Defecography in multiple sclerosis patients with severe constipation   总被引:3,自引:0,他引:3  
Gill  KP; Chia  YW; Henry  MM; Shorvon  PJ 《Radiology》1994,191(2):553
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Previous reports in the literature have described correlation of increasing repeat length with severity of the phenotype, in Kennedy syndrome. We describe male siblings with different repeat lengths, with lack of expression of the phenotype in the sibling with the longer repeat length. The phenotype was identical to motor neurone disease. There is variability of expression in Kennedy syndrome and repeat length even in siblings cannot be taken as a conclusive indicator of severity. CAG repeat length cannot be used to predict the natural history of Kennedy disease. The diagnosis of Kennedy syndrome should be considered in male patients presenting with atypical motor neurone disease.  相似文献   
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SUMMARY The interferons are natural glycoproteins secreted in response to various stimuli, including viral infection. They have antiviral, antiproliferative and immunomodulatory effects on different target cell populations. Since recombinant human interferons have become available, they have been tested in a wide range of malignancies. They are well established in the treatment of hairy cell leukaemia, chronic myelogenous leukaemia and multiple myeloma. Although they have documented activity against lymphoma, melanoma, renal cell cancer and carcinoid tumours, their role in the treatment of these tumours is less clear. In the common solid tumours, such as lung cancer and colorectal cancer, the use of interferons remains experimental. Here we will summarise their practice applications in oncology, using randomised studies where available to establish their place in multi-modality treatment. We will not discuss their use as antiviral or immunomodulating agents in viral and autoimmune diseases, multiple sclerosis or after organ transplantation.  相似文献   
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Chronic low back pain: comparison of bone SPECT with radiography and CT   总被引:1,自引:0,他引:1  
Ryan  PJ; Evans  PA; Gibson  T; Fogelman  I 《Radiology》1992,182(3):849
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Although present sonomicrometer techniques for measuring continuous changes in vascular diameter are very useful, two problems with available methods are difficulty in maintaining crystal alignment throughout an acute experiment and inability to measure absolute dimensions less than 1 mm. We have designed and ultrasonic dimension gauge system to over come these problems. The design uses a gate to pass a 20 MHz signal to a counter during the sonic travel time between crystals, and then converts the digital count to an analogue voltage. Interference from the transmitting impulse in the received signal was minimised using MOSFET transistors allowing measurements of absolute dimensions from 0.00 mm to 99.9 mm. An averaging effect which depends upon the asynchrony between the basic timer and the counter clock results in a resolution of at least 10 μm. Repeated calibration curves showed an accuracy of 2.5 μm without significant bias. Piezoelectric crystals were mounted to a lighweight stainless-steel clip to facilitate attachment to the vessel and to maintain the crystals in focus during changes in diameter. Mean and phasic diameters measured in the femoral artery with the clip device correlated well with measurements obtained with crystals sewn to the adventitia of the femoral artery of the dog (slope =0.97, r=0.99).  相似文献   
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