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41.
42.
家族性特发性基底节钙化 总被引:1,自引:0,他引:1
家族性特发性基底节钙化(familial idiopathic basal ganglia calcification,FIBGC)是一种以影像学上有基底节及脑其他部位钙化为特征的神经系统变性疾病。大多数患在童年及青少年时期是健康的,而到了30-50岁时,典型患会逐渐出现神经精神以及运动障碍。首发症状通常包括动作笨拙、易疲劳、步态不稳、言语缓慢、吞咽困难、不自主运动、肌肉痉挛等,经常会有各种类型的癫痫发作。神经精神症状往往是首发或最突出的表现,轻仅仅为轻度注意力或记忆力的下降,重则会出现人格及行为改变,终致精神病或痴呆。[第一段] 相似文献
43.
Håkan Eriksson Joakim Tedroff Karl-Åke Thuomas Sten-Magnus Aquilonius Per Hartvig Karl-Johan Fasth Peter Bjurling Bengt Långström Karl-Göran Hedström Edith Heilbronn 《Archives of toxicology》1992,66(6):403-407
A series of positron emission tomography scans was made on two monkeys during a 16-month period when they received manganese(IV)oxide by subcutaneous injection. The distribution of [11C]-nomifensine uptake, indicating dopamine terminals, was followed in both monkey brains. The brain distributions of [11C]-raclopride, demonstrating D2 dopamine receptors, and [11C]-l-dopa, as a marker of dopamine turnover, were followed in one monkey each. The monkeys developed signs of poisoning namely unsteady gait and hypoactivity. The [11C]-nomifensine uptake in the striatum was reduced with time and reached a 60% reduction after 16 months exposure. This supports the suggestion that dopaminergic nerve endings degenerate during manganese intoxication. The [11C]-l-dopa decarboxylation was not significantly altered indicating a sparing of [11C]-l-dopa decarboxylation during manganese poisoning. A transient decrease of [11C]-raclopride binding occurred but at the end of the study D2-receptor binding had returned to starting values. The magnetic resonance imaging (MRI) revealed that the manganese accumulated in the globus pallidus, putamen and caudate nucleus. There were also suggestions of gliosis/edema in the posterior limb of the internal capsule. MRI might be useful to follow manganese intoxication in humans as long as the scan is made within a few months of exposure to manganese, i. e. before a reversal of the manganese accumulation. 相似文献
44.
Richard H. Price Jr. Zane Hollingsworth Anne B. Young John B. Penney Jr. 《Brain research》1993,602(1)
The subthalamic nucleus plays a pivotal role in the regulation of basal ganglia output. Recent electrophysiologic, lesion and immunocytochemical studies suggest that the subthalamic nucleus uses an excitatory amino acid as a neurotransmitter. After complete ablation of the subthalamic nucleus, we have examined the NMDA, AMPA, kainate and metabotropic subtypes of excitatory amino acid receptors in two major subthalamic projection areas (globus pallidus and substantia nigra pars reticulata) with quantitative autoradiography. Two weeks after ablation, binding sites for [3H]AMPA and [3H]kainate increased in substantia nigra pars reticulata ipsilateral to the lesion. In globus pallidus on the lesioned side, [3H]glutamate binding to the NMDA recognition site decreased. The results suggest that glutamate receptors regulate after interruption of subthalamic nucleus output. 相似文献
45.
构建具有λPR与T7双启动动子的新型原核表达载体pDOG,以便使用同一载体研究不同诱导条件下,重组蛋白在大肠杆菌中表达,降解以及折叠的情况,从而选择最佳的诱导条件。方法采用pBV220与PET-3表达载体作为原始材料,将PET-3上包括T7启动子与T7g-10释译起始序列的一段序列克隆到 相似文献
46.
Reliability of a Core Competency Checklist Assessment in the Emergency Department: The Standardized Direct Observation Assessment Tool 总被引:2,自引:1,他引:1
47.
H. Maeda M. Sato A. Yoshikawa M. Kimura T. Sonomura M. Terada K. Kishi 《Neuroradiology》1997,39(8):546-550
In patients with hepatic cirrhosis, the globus pallidus and putamen show high intensity on T1-weighted MRI. While the causes
of this high signal have been thought to include paramagnetic substances, especially manganese, no evidence for this has been
presented. Autopsy in four cases of hepatic cirrhosis permitted measurement of metal concentrations in brain and histopathological
examination. In three cases the globus pallidus showed high intensity on T1-weighted images. Mean manganese concentrations
in globus pallidus, putamen and frontal white matter were 3.03 ± 0.38, 2.12 ± 0.37, and 1.38 ± 0.24 (μg/g wet weight), respectively,
being approximately four- to almost ten-fold the normal values. Copper concentrations in globus pallidus and putamen were
also high, 50 % more than normal. Calcium, iron, zinc and magnesium concentrations were all normal. The fourth case showed
no abnormal intensity in the basal ganglia and brain metal concentrations were all normal. Histopathologically, cases with
showing high signal remarkable atrophy, necrosis, and deciduation of nerve cells and proliferation of glial cells and microglia
in globus pallidus. These findings were similar to those in chronic manganese poisoning. On T1-weighted images, copper deposition
shows no abnormal intensity. It is therefore inferred that deposition of highly concentrations of manganese may caused high
signal on T1-weighted images and nerve cell death in the globus pallidus.
Received: 12 August 1996 Accepted: 17 December 1996 相似文献
48.
Sensitization of striatal N-methyl-
-aspartate receptors (NMDAR) has been linked to events leading to the motor response changes associated with the administration of dopaminomimetics to parkinsonian animals and patients. To determine whether tyrosine phosphorylation of NMDAR subunits contributes to the apparent long-term enhancement in synaptic efficacy of these receptors, we examined the effect of unilateral nigrostriatal dopamine system ablation with 6-hydroxydopamine followed by twice-daily treatment with
-DOPA on the phosphorylation state of rat striatal NR2A and NR2B subunits. Three weeks of intermittent
-DOPA administration produced a shortening in the duration of the rotational response to dopaminergic challenge and other changes mimicking those occurring in patients with Parkinson's disease. Concurrently, tyrosine phosphorylation of NR2A and especially of NR2B subunits increased ipsilateral to the lesion (20±5% and 46±7% of intact striatum, respectively; p<0.01) without attendant changes in subunit protein levels. Selective blockade of NR2B subunits with ACEA 10-1244, but not of NR2A subunits with MDL 100,453, reversed the
-DOPA-induced response alterations. The intrastriatal injection of a tyrosine kinase inhibitor, genistein, at a dose (2.0 μg) that normalized the response shortening, attenuated the NR2A and NR2B phosphorylation increase by about 12% and 24%, respectively (p<0.01). Taken together, these results suggest that augmented tyrosine phosphorylation of NR2B subunits, alone or in combination with the smaller rise in NR2A subunit phosphorylation, contributes to the apparent enhancement in striatal NMDAR sensitivity and thus to the plastic alterations in dopaminergic responses in
-DOPA-treated parkinsonian rats. 相似文献
49.
Summary Follow-up data are presented of ten patients with autopsy-proven postencephalitic Parkinson's syndrome (PEP) (mean age at death: 56.0 years) with regard to motor and psychic deterioration over a period of institutional observation between 3 and 30 years. Four patients showed deterioration of their Hoehn-Yahr score of at least one grade. These patients did not differ statistically with respect to age of occurrence of lethargic encephalitis, interval to PEP, age at start of PEP, duration of survival with PEP, and age at death. Motor deterioration in these patients seems to be attributed more to inherent disease progression, rather than to an age-related process. Clinical and pathological evidence for this conclusion is presented. 相似文献
50.
目的:探讨治疗自发性基底节出血的有效措施。方法:将1997年9月-2001年10月采用显微手术治疗的96例自发性脑出血患者,与1994年9月-1997年8月采用常规开颅清除血肿的88例同类患者,在术后血肿清除率,手术死亡率和致残率等方面作对比研究。结果:显微手术能显著提高血肿清除率(P<0.05)、降低术后脑水肿反应发生率(P<0.01),从而显著降低了手术死亡率(P<0.05)和致残率(P<0.05)。结论:显微手术是治疗自发性脑出血患者一种有效的手术方式。 相似文献