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61.
Summary Ninety outpatients with Alzheimer's disease according to ICD-10 diagnostic draft criteria were studied to test the hypothesis that cases with a familial aggregation are different from cases without such an aggregation with respect to cognitive impairment. In all cases the diagnosis of Alzheimer's disease was confirmed by prospective observation within 12 months of initial evaluation. Patients were divided into two groups: one consisting of 23 patients with a familial aggregation, the other consisting of 67 patients without secondary cases among first-degree relatives. By means oft-tests differences in impairment of cognitive functions between the groups were calculated. The results did not yield statistically significant differences between the groups for any of the neuropsychologically investigated cognitive deficits. Thus the hypothesis that the presence of a familial aggregation may lead to a distinct phenotype in Alzheimer's disease was not confirmed.  相似文献   
62.
MRI of the brain in chronic carbon monoxide poisoning   总被引:3,自引:0,他引:3  
We examined 13 patients with chronic carbon monoxide (CO) poisoning by magnetic resonance imaging (MRI); all of them had been in an explosion in a coal mine 25 years previously. Symmetrical globus pallidus lesions were observed in 12, as was degeneration of the white matter, with focal cortical atrophy. The temporal parietal and occipital lobes were usually affected, the parietooccipital region being the most frequently and extensively damaged. Of the 12 patients with white matter degeneration 7 had definitely asymmetrical cortical and subcortical lesions. There were 6 patients with dilated temporal horns, probably due to atrophy of the hippocampal gyri. A history of CO inhalation and an awareness of the typical distributions of lesions are important for recognition of the effects of CO poisoning, especially when patients are in the chronic stage.  相似文献   
63.
64.
本文对59名接触实验动物大白鼠引起23例流行性出血热(EHF)的流行病学和临床症状进行了调查,发病率为38.98%。发病的有副教授、讲师、助教、研究生等。发病多在春季,年龄组在21~40岁,男多于女。经间接免疫荧光技术检查,大白鼠肺EHFV抗原阳性率为32.69%。临床分型以中型为多,其次为重型和轻型。临床症状以发热、头痛、腰痛、全身痛、食欲不振、酒醉貌为主,没有死亡病例。血清间接免疫荧光抗体IgG在1:320~1:5 120之间的占91.30%。  相似文献   
65.
目的利用扩散张量成像(DTI)直方图分析,明确血管性认知损害(VCI)患者的脑异常改变及DTI直方图指标与简易智能量表(MMSE)评分的相关性。方法对19例VCI患者和19例健康志愿者行常规MRI和DTI检查,获得全脑平均扩散率(MD)和各向异性分数(FA)图像后,分别绘制出全脑FA和MD直方图并对其进行分析。结果VCI患者的全脑MD和FA直方图与正常志愿者不同。与正常对照比较,VCI患者平均全脑FA直方图示峰位置左移、平均FA值降低(P=0.008),MD直方图右移、平均MD值增高(P=0.026),峰位置增高(P=0.041),峰高降低(P=0.002)。平均FA值(r=-0.486,P=0.036)、FA峰高(r=0.498,P=0.030)和FA峰位置(r=-0.641,P=0.003)与MMSE评分相关。结论VCI的患者存在脑扩散异常,DTI直方图部分指标可以帮助评价认知功能损害的严重程度。  相似文献   
66.
在1000人中统计白鼻毛发生率为36.4%,白发为26.1%,白须为7.5%,白眉为3.3%,白睫为1.6%。我们认为白鼻毛比白发等作为衰老的一项指标更有其代表性。白鼻毛发生率:男性(53.4%)高于女性(13.4%),知识分子(60.8%)高于工人(26.3%)及农民(26.4%),日本人高于中国人,差异显著。  相似文献   
67.
68.
It is shown that a repetitive pulse sequence consisting of two 90° pulses and gradients in a 1:2 ratio around the second 90° pulse generates interscan shifted stimulated echoes (SSTEs) and intrascan multiple spin echoes (MSEs). Separation of these two types of signals is accomplished using specific gradient crusher schemes. The intensity of the SSTEs is an order of magnitude larger than that of the MSEs and determines the signal contrast if both effects are selected simultaneously. The SSTE sequence generates improved contrast between gray and white matter, even at high field, which is explained in terms of increased inverse T1-weighting for the interscan echo. The MSE image has low signal to noise and no detectable contrast. The effect of interscan diffusion weighting is also discussed.  相似文献   
69.
The motor impairing effects and plasma concentrations of barbital and lorazepam were studied in the alcohol tolerant (AT) and alcohol non-tolerant (ANT) rat lines developed for low and high sensitivity to motor impairment from ethanol. The mixed (M) line, from which the AT and ANT rats were derived, was also included in the study. Like ethanol, barbital and lorazepam impaired the performance of the ANT rats more than that of the AT rats. The motor performance of the M rats was relatively more impaired after barbital than after lorazepam administration at the same dose used in the AT and ANT rats. At the two latter time points (2.5 and 3.5 h) the sensitive ANT rats had significantly higher serum barbital concentrations than the AT rats. The serum barbital concentrations of the AT and ANT rats did not differ, however, at the two first time points (0.5 and 1.5 h) of the tilting plane tests, although the ANT rats were significantly more intoxicated. The concentrations of lorazepam in plasma do not explain the differential motor impairment either, since the sensitive ANT rats had lower plasma concentrations than the insensitive AT rats. The results, thus, suggest that the selection involved in the development of the AT and ANT lines has not been specific for ethanol. The results also support the idea that ethanol, barbiturates and benzodiazepines have some modes of action in common.  相似文献   
70.
动脉硬化性脑白质病的CT表现与临床分析   总被引:1,自引:0,他引:1  
目的 :探讨动脉硬化性脑白质病的临床与CT表现特点。方法 :收集 10 0例动脉硬化性脑白质病的临床与CT资料进行综合分析。结果 :10 0例的CT表现为 :弥漫性脑白质低密度改变 ,主要分布在双侧脑室旁及半卵圆中心白质区 ,病灶多呈条带状及月晕状。合并脑萎缩 90例 ;脑梗塞 76例 ,其中 2 5例有大的梗塞灶 ,其余为腔隙性梗塞 ;脑出血 9例 ,其中位于壳核 5例 ,丘脑 3例 ,小脑 1例 ;有 15例伴发基底节区软化灶。增强扫描 8例 ,显示病灶无明显增强。结论 :动脉硬化性脑白质病是发生于老年人的缺血性脑血管病 ,高血压动脉硬化是其主要发病因素。  相似文献   
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