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21.
We report a patient manifesting seizures with bilateral symmetric tonic posturing, which were markedly reduced after resection of the left precuneus. A 16-year-old man had sudden onset, complex partial seizures with bilateral symmetric tonic posturing since the age of eight years. Magnetic resonance fluid-attenuated inversion-recovery imaging revealed a hyperintense lesion in left precuneus. In almost all focal seizures recorded during an invasive EEG evaluation, ictal onset was detected from the inferomesial aspect of the lesion, but fast paroxysmal discharges from the ipsilateral supplementary motor area (SMA) were observed just before the clinical onset. After surgical excision of the EEG onset zone, including the lesion, seizure frequency was markedly (> 95%) reduced. By the 20th month after surgery, there were only brief nocturnal seizures involving slight elevation of both shoulders and slight abduction of both arms, with preservation of consciousness occurring once every few days. Invasive EEG findings and surgical outcome suggested that the epileptic activity originating from the epileptogenic zone may have propagated to the symptomatogenic zone including mainly the ipsilateral SMA. In summary, we report an interesting case of bilateral symmetric tonic posturing suggesting propagation to the SMA. MRI and invasive EEG confirmed the epileptogenic focus as a precuneate cortical dysplasia lesion.[Published with video sequences].  相似文献   
22.
We report a case with a unilateral sudden sensorineural hearing loss caused by an infarction of brainstem and cerebellum. The patient was a 74-year-old male presented with a sudden onset of hearing loss and tinnitus in the right ear and dizziness. Steroid was administered on suspicion of idiopathic sudden deafness. However, the initial symptoms were deteriorated approximately 2 weeks later. He newly complained of the numbness of the right face and double vision, and he was transferred to our hospital for further evaluation. Neurological examination demonstrated horizontal nystagmus, diminution in the right facial sensation, right peripheral facial palsy, right hearing loss and cerebellar ataxia. Urgent MRI disclosed fresh infarctions of the right middle cerebellar peduncle and cerebellum localized in the territory of anterior inferior cerebellar artery. In general, idiopathic sudden deafness and Meniere's disease are frequent diagnosis in cases of sudden hearing loss with vertigo, but these symptoms may rarely be caused by cerebrovascular disorder. In patients with risk factors for arteriosclerosis, cerebrovascular disorder should be taken into consideration even if idiopathic sudden deafness may be suspected clinically. We emphasize the diagnostic importance of careful observation on neurological findings and early detection of radiological abnormalities on MRI.  相似文献   
23.
Lmmunohistochemical analyses were made of the superoxide dismutases (Mn-SOD and CuiZn-SOD) in biopsied muscles from 7 patients with mitochondrial encephalomyopathies that included mitochondrial encephalomyopathy, lactic acidosis and strokelike episodes (MELAS), and chronic progressive external ophthalmoplegia (CPEO). Mn-SOD mainly was present in the subsarcolemmal region, but it also was found in a coarsely granular, reticular, or diffuse pattern of staining within the muscle fibers. These Mn-SOD-positive fibers corresponded almost completely to the ragged-red fibers. The immunoreaction for CuiZn-SOD was weakly positive in some of the muscle fibers positive for Mn-SOD. In CPEO, Mn-SOD-positive fibers predominantly showed decreased cytochrome c oxidase (COX) activity. In MELAS, Mn-SOD-positive fibers tended to be stained deeply for COX although a few were COX-negative. These findings suggest that Mn-SOD-positive fibers can be used to make a differential diagnosis between CPEO and MELAS and that in mitochondrial encephalomyopathies Mn-SOD in the raggedred fibers may protect against oxidative stress. © John Wiley & Sons, Inc.  相似文献   
24.
We performed human leukocyte antigens(HLA)typing for class I antigens on 19 Japanese patients with Fisher's syndrome. We demonstrated a statistically significant association between the disease and the HLA-B39 antigen.  相似文献   
25.
Summary We studied senile plaques (SP) in the cerebella of six autopsied subjects with Alzheimer-type dementia (ATD) and ten non-ATD autopsied subjects between the ages of 78 and 90. Neither SP nor amyloid angiopathy (AA) was observed in any of the non-ATD subjects. In the four of the six ATD subjects, diffuse plaques in the molecular layer were seen as ill-defined areas of fine fibrillar materials by protein immunostaining with formic acid pretreatment, the modified Bielschowsky stain, and periodic acid-methenamine silver (PAM) stain. The plaques were not visible with Bodian, Congo red, or periodic acid-Schiff stains. Compact plaques in the Purkinje cell or in the granular cell layers were found in three of the six subjects. Their amyloid core was often surrounded by areolar amyloid deposits. AA was observed in three of the six subjects. The argyrophilia of the diffuse and compact plaques, demonstrated by the modified Bielschowsky and PAM stains, became undetectable when the sections were first treated with formic acid. Such treatment made the plaques immunoreactive with protein antiserum. The findings suggested that cerebellar diffuse plaques and compact plaques consist mainly of an amyloid component, and are characteristic of ATD.  相似文献   
26.
27.
Soluble membrane cofactor protein (MCP, CD46) has not been detected by conventional ELISA in human urine. Here, we established a highly sensitive assay method for determination of urinary MCP (uMCP) using monoclonal antibody-coated paramagnetic beads. This method enabled us to detect less than 0.05 ng/ml of purified membrane and recombinant soluble MCP, a sensitivity 10-fold higher than that of conventional ELISA. In normal subjects, the levels of uMCP were <0. 05 ng/ml. The levels of uMCP were elevated in patients with IgA nephropathy and more prominently in patients with rapidly progressive glomerulonephritis. The levels of uMCP were correlated significantly with those of serum MCP (sMCP) and N-acetyl-beta-glucosaminidase and nonsignificantly with those of beta(2)-microglobulin, total urine protein, or serum creatinine. The properties of uMCP were inconsistent with those of the reported sMCP, since uMCP showed three bands on SDS-PAGE/immunoblotting with molecular mass profiles different from those of sMCP. uMCP exhibited factor I cofactor activity for cleavage of C3b comparable to that of sMCP. The origin of uMCP, however, remains to be determined. These results, taken together with the parameter correlation profiles, suggested that uMCP is secreted or produced secondary to tubular or glomerular damage. The physiological role and clinical significance of uMCP are now within the scope of our investigation by establishment of this assay.  相似文献   
28.
Adenohypophyses of porcine fetuses from 25 to 110 days of gestation were studied by immunohistochemical staining to ascertain the ontogeny of specific cell types and their spatial distribution in the pars distalis. No hormonecontaining cells were found before 30 days of gestation. ACTH cells were observed first at 40 days, while GH and LH cells appeared first at 60 days. PRL cells were initially detected at 105 days. ACTH immunoreactive cells were also observed in the pars intermedia at 40 days. Blood capillaries were interposed between cell cords of the pars distalis after 40 days of gestation. ACTH cells were evenly distribution in all areas of the pars distalis except the rostal area (sex zone). GH cells were densely distributed in lateral wings of the pars distalis and immediately anterior to Rathke's lumen. PRL cells resembled GH cells in their distribution pattern, but PRL cells were fewer in number. LH cells were scattered in the sex zone of the pars distalis from 60 to 80 days of gestation. After 90 days, they became scattered throughout the pars distalis but were more numerous in the sex zone than in other areas. The inductive elements of adenohypophysial cells from Rathke's pouch epithelia are discussed. We hypothesize that cell cords of specific areas facing Rathke's lumen may differentiate into specific cell types of the pars distalis during fetal life. © 1992 Wiley-Liss, Inc.  相似文献   
29.
Summary The effects of local heating on finger blood flow (BF) and local thermal sensation (Sens w ) were studied. Finger BFs in both hands were measured simultaneously; one hand was immersed in water the temperature (T w ) of which was raised from 35° C to 43°C by steps of 2° C every 10 min, while the other hand was kept atT w 35°C. FingerBF in the locally heated hand decreased atT w 37 to 41°C, while fingerBF in the control hand did not alter. Sensw, in the heated hand showed a dynamic response, initially increasing concomitantly with an increase inT w , then gradually returning and adapting to a new level of Sensw. The dynamic response of Sensw, was not perceived during mental calculation even whenT w was raised to 40°C, and the reduction in finger blood flow was not observed. These results suggest that finger vasoconstriction caused by local heating closely relates to the dynamic response characteristic of local thermal sensation atT w above core temperature, and that the perception of local thermal sensation in the central nervous system is involved in the mechanism of this vasoconstrictor response.  相似文献   
30.
The gene encoding Clostridium sordellii phospholipase C (Csp) was cloned and expressed as a histidine-tagged (His-tag) protein, and the protein was purified to compare its enzymatic and biological activities with those of Clostridium perfringens phospholipase C (Cpa) and Clostridium bifermentans phospholipase C (Cbp). Csp was found to consist of 371 amino acid residues in the mature form and to be more homologous to Cbp than to Cpa. The egg yolk phospholipid hydrolysis activity of the His-tag Csp was about one-third of that of His-tag Cpa, but the hemolytic activity was less than 1% of that of His-tag Cpa. His-tag Csp was nontoxic to mice. Immunization of mice with His-tag Cbp or His-tag Csp did not provide effective protection against the lethal activity of His-tag Cpa. These results indicate that Csp possesses similar molecular properties to Cbp and suggest that comparative analysis of toxic and nontoxic clostridial phospholipases is helpful for characterization of the toxic properties of clostridial phospholipases.  相似文献   
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