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91.
Several biological theories were proposed to explain symptoms of childhood autism in terms of monoamine metabolic dysfunction. Clinical, electrophysiological and biochemical markers which support the dopaminergic hypothesis will be given in this paper. A factorial analysis, performed on the 'behavior summarized evaluation' (BSE, scoring behavioral data), exhibits a first component corresponding to the autistic DSM III criteria, and also shows that the disturbances of attention and perception belonged to this component. So, as well as communication, selective attention, perception and gestures, usually considered as regulated by the dopaminergic system are deeply modified and appeared as primary symptoms in autistic syndromes. Many electrophysiological data recorded in autistic children suggest both faulty modulation of sensory input and deficiency in dealing with sensory cross-modal association which have been related to a dysfunctioning of the dopaminergic system. Elevated homovanillic acid levels, the main dopamine metabolite, have been attributed to a reduced re-uptake of dopamine related to a 'longer occupation' of the receptors which is in agreement with the electrophysiological 'sensory overload'. The relationships found between these markers are discussed. Such an approach would contribute to a better understanding of the underlying mechanism of autism.  相似文献   
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The fibrinogen activity in thawed cryoprecipitate stored between 1 and 6 degrees C is maintained essentially unchanged in most bags for a month. Occasionally, a bag will have a reduction in fibrinogen. If pooling has not occurred, thawed cryoprecipitate should be useful as a source of fibrinogen for a period of time considerably in excess of the 6 hours allowed for its use as a source of factor VIII or von Willebrand factor.  相似文献   
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Alterations in phagocytosis have been studied in 25 patients with idiopathic nephrotic syndrome (INS). At the time of investigation all patients had normal renal function.  相似文献   
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Aortic dissection: magnetic resonance imaging   总被引:2,自引:0,他引:2  
Amparo  EG; Higgins  CB; Hricak  H; Sollitto  R 《Radiology》1985,155(2):399-406
Fifteen patients with suspected or known aortic dissection were imaged with magnetic resonance (MR). Thirteen of these patients were eventually shown to have dissection. In most instances the diagnosis was established by aortography and/or computed tomography (CT) prior to the MR study. Surgical proof (6/13) and/or aortographic proof (10/13) were available in 11/13 patients with aortic dissection. MR demonstrated the intimal flap and determined whether the dissection was type A or type B. In addition, MR: differentiated between the true and false lumens; determined the origins of the celiac, superior mesenteric, and renal arteries from the true or false lumen in the cases where the dissection extended into the abdominal aorta (8/12); allowed post-surgical surveillance of the dissection; and identified aortoannular ectasia in the three patients who had Marfan syndrome. In addition to the 13 cases with dissection, there were two cases in whom the diagnosis of dissection was excluded by MR. Our early experience suggests that MR can serve as the initial imaging test in clinically suspected cases of aortic dissection and that the information provided by MR is sufficient to manage many cases. Additionally, MR obviates the use of iodinated contrast media.  相似文献   
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Peripheral vascular disease: correlation of MR imaging and angiography   总被引:1,自引:0,他引:1  
The capability of magnetic resonance (MR) imaging for detecting aortic, iliac, and femoral stenoses and occlusions was evaluated. Multisection spin-echo studies at 0.35 tesla were obtained of the infrarenal aorta to the femoral bifurcation in 24 patients, all of whom had undergone intraarterial angiography within 14 days of imaging. Transaxial MR images were compared with the angiograms. Arterial stenoses and occlusions in these vessels detected by MR imaging correlated with angiographic findings in 91% of the instances. Protrusional atherosclerotic plaques and occlusions and stenoses in the aortoiliac region were demonstrated accurately on MR images; complications of previous vascular surgery, such as aneurysms at sites of previous anastomoses or endarterectomy, were also identified. Due to the limited spatial resolution, MR images failed to demonstrate some femoral stenoses. MR imaging may be used for evaluation of aortoiliac vascular disease and for follow-up study after surgical revascularization. However, the limited spatial resolution, noncomposite display of the aortoiliofemoral circulation, and lack of evaluation of peripheral runoff provided by current MR imaging techniques militate against its replacing angiography prior to vascular intervention.  相似文献   
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