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91.
92.
A family is described in which 2 siblings born to healthy parents presented with abnormal facies, persistent diarrhoea, and early death. Exhaustive pathological and biochemical investigations failed to find a cause. The scalp hair of both babies had an abnormal amino-acid composition, and presented an appearance that was unique on scanning electron microscopical examination; this fact and the clinical picture probably represents a new syndrome.  相似文献   
93.
94.
Pineal germinoma: MR imaging   总被引:6,自引:0,他引:6  
Magnetic resonance (MR) imaging characteristics of pineal germinomas are described in seven patients imaged with MR and computed tomography (CT). In patients with symptoms of an enlarging process in the quadrigeminal plate cistern, MR imaging was as sensitive as CT scanning in detecting the mass. MR imaging did not detect a normal-sized, calcified neoplastic gland. Germinoma, germinoma with embryonal cell carcinoma elements, and pineoblastoma demonstrated different MR signal characteristics. Although direct coronal and sagittal MR images were useful in defining the relationship of the tumor to the posterior third ventricle, Sylvian aqueduct, and vein of Galen, the ease, rapidity, and sensitivity of CT scanning suggest that CT should remain the modality of choice for initial evaluation and screening of the pineal region, especially in the younger pediatric population, in whom detection of calcification may provide the only clue of an abnormality.  相似文献   
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It remains an open question as to whether cortical spreading depression (CSD) is the pathophysiological correlate of the neurological symptoms in migraine with aura. In the experimental animal, CSD is an electrophysiological phenomenon mainly mediated via NMDA receptors. However, according to case reports in humans, visual aura in migraine can be alleviated by vasodilator substances, such as amyl nitrite and isoprenaline. There is also circumstantial evidence that brainstem nuclei (dorsal raphe nucleus and locus coeruleus) may play a pivotal role in the initiation of aura. In this study, CSD was elicited in alpha-chloralose anesthetized cats by cortical needle stab injury and monitored by means of laser Doppler flowmetry. Topical application of isoprenaline (0.1-1%) and amyl nitrite (0.05%) onto the exposed cortex had no effect on the elicitation or propagation of CSD. Also, after supracollicular transection, subsequent CSDs showed no differences in the speed of propagation and associated flow changes. We conclude from these data that--given CSD probably exists in humans during migraine--spreading neurological deficits during migraine aura are independent of brainstem influence and have a primarily neuronal rather than vascular mechanism of generation.  相似文献   
97.
Rothko  K; Kickler  TS; Clay  ME; Johnson  RJ; Stroncek  DF 《Blood》1989,74(5):1698-1703
We characterized neutrophil autoantigens using an immunoblotting technique with antibodies obtained from patients with autoimmune neutropenia. These results were correlated with serologic characterization of the antibodies, using indirect immunofluorescence and leukoagglutination. Of the 17 sera immunoblotted, 16 showed discrete bands in the molecular weight range of 30 to 112. Three patients with Felty's syndrome reacted with an antigenic target of 80 to 84 Kd molecular mass, a finding not seen in any of the other patients studied. By serologic testing, none of the autoimmune sera showed serologic specificity for any known neutrophil-specific alloantigen. Using an anti-NA-1 serum, we identified antigenic targets at 40, 50, and 101 Kd in both NA-1-positive and NA-1-negative neutrophils. Ten of 17 autoimmune sera showed reactivity in this corresponding range. These studies demonstrate that immunoblotting may be used to identify antigenic targets in autoimmune neutropenia and may suggest a specificity of these antibodies not definable by serologic techniques. Correlation of immunoblot reactivity with disease states associated with immune neutropenia may be useful in the study of the pathogenesis of the different forms of autoimmune neutropenia.  相似文献   
98.
99.
Left ventricular volume has been measured with ultrafast computed tomography. However, the accuracy with which this can be done is unknown. We therefore imaged with ultrafast computed tomography 11 rectangular phantoms, 20 to 225 ml, and 17 left ventricular casts, 15 to 112 ml. Two observers planimetered serial tomographic images and computed volume from sequential tomograms. There was no significant inter- or intraobserver difference in measurement of phantoms. Deviation of ultrafast computed tomographic volume from true phantom volume was -0.1 +/- 3.5% SD, range 9.0 to -7.6%. Correlation of true phantom volume with ultrafast computed tomographic volume was 0.99, SEE = 1.9 ml. No significant difference was observed between merged and single ultrafast computed tomographic scanning sequences. Left ventricular cast volume determined by ultrafast computed tomography deviated from true volume by 6% +/- 20%, range 54% to -45%. Correlation of true volume with ultrafast computed tomographic volume was 0.99, SEE = 5.1 ml. There was no interobserver significant difference in measurement of left ventricular cast volume. Correlation between ultrafast computed tomographic volume and cineradiographic volume of the same left ventricular casts was 0.99, SEE = 4.4 ml. Thus, phantom volumes can be measured accurately without significant intra- or interobserver variation. Merged scanning sequences did not influence volume determination. Left ventricular cast volume determination was comparable to that obtained with cineradiography.  相似文献   
100.
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