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31.
Summary Methods in current practice for ascertaining time of death are largely based on the cooling of the body after death and are
somewhat unreliable. A theoretica relationship is known to exist between the decline in the properties defining nerve conduction
and time after death caused by the gradual cessation of metabolic activity in nerves. A number of such properties were measured
in rats during life and after death. In most cases the relationship was found to be inconsistent. The chronaxie of the strength
duration curve for the sciatic nerve was, however, found to increase consistently and reproducibly in a linear fashion over
the first 90 min after death to a plateau value which was maintained beyond 135 min. These findings are discussed as the possible
basis of a forensic method of determining the duration of the “post mortem interval” within the first few hours after death.
相似文献
32.
用玻璃纤维表面处理剂MAC处理玻璃纤维后,再进行臭氧处理,使玻璃纤维的表面产生活性中心,引发苯乙烯、甲基丙烯酸甲酯、及丙烯酸等乙烯基单体在玻璃纤维表面上接枝聚合。接枝纤维的密度减小,对水的浸润性下降,红外光谱及扫描电镜观察证明玻璃纤维表面上接枝聚合物的存在。 相似文献
33.
CHRISTOPH STELLBRINK KLAUS-PETER KUNZE PETER HANRATH 《Pacing and clinical electrophysiology : PACE》1995,18(9):1717-1720
STELLBRINK, C., et al .: Preexcitation in Hypertrophic Cardiomyopathy: A Case of a Fasciculoventricular Mahaim Fiber . A patient with hypertrophic cardiomyopathy (HCM) who presented with preexcitation pattern on the surface ECG suggestive of the Wolff-Parkinson-White (WPW) syndrome is described. Intracardiac electrophysiological study revealed a fixed anomalous QRS complex and a short fixed His-ventricular interval indicating a fasciculoventricular Mahaim fiber. As this specific form of accessory connection does not cause reentrant tachycardias, no treatment was required. It is important to distinguish this entity from atriofascicular or nodoventricular Mahaim fibers or the WPW syndrome in patients with HCM showing a preexcitation pattern in the surface ECG, as these may cause life-threatening arrhythmias in this patient population. 相似文献
34.
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36.
复合膳食纤维对大鼠体内脂质过氧化作用的影响 总被引:5,自引:1,他引:4
制备复合膳食纤维 (dietaryfiber,DF) ,并分别探讨复合、混合及三种单一的DF对高脂血症大鼠体内脂质过氧化作用的影响。选健康、断乳Wistar大鼠 6 4只 ,按体重随机分为 8组 ,用高脂饲料诱发高脂血症的同时 ,分别添加 10 %的DF :纤维素 (B组 )、果胶 (C组 )、海藻酸钠 (D组 )、纤维素 -果胶复合物 (E组 )、纤维素 -海藻酸钠复合物 (F组 )、纤维素 -果胶混合物 (G组 )、纤维素 -海藻酸钠混合物 (H组 ) ,以单纯的高脂饲料组为对照组 (A组 ) ,观察各种DF对大鼠的生长发育及脂质过氧化作用的影响。结果显示 :1、添加 10 %的各种DF不影响大鼠的生长发育。 2、各种DF皆可显著升高血清超氧化物歧化酶 (SOD) (P <0 0 1)、谷胱甘肽过氧化物酶 (GSH Px)活性 (P <0 0 1) ,降低丙二醛 (MDA)水平 (P <0 0 5 ,B、D组除外 ) ,提高红细胞膜的流动性 (P <0 0 5 ) ,以复合物、混合物效果为明显。 3、各种DF可不同程度地增加粪重和粪脂排出量 (P <0 0 5 ,D组除外 ) ,以复合物、混合物为明显。提示各种DF皆可不同程度地降低大鼠体内脂质过氧化作用 ,提高红细胞膜的流动性 ,其中可溶性DF效果优于不可溶性DF ,而复合、混合DF的效果又优于单一的DF ,且以复合物效果为佳 相似文献
37.
Neuromuscular transmission as a function of motor unit size in patients with prior poliomyelitis. 总被引:2,自引:0,他引:2
We studied neuromuscular transmission in 16 patients with prior poliomyelitis by measuring single fiber electromyographic (SFEMG) jitter. This was compared with 3 indirect methods of assessing reinnervation: SFEMG fiber density, macro EMG, and the presence of fiber type grouping on muscle biopsy. In patients with acute poliomyelitis before the age of 10, there was a positive correlation between the extent of neuromuscular transmission impairment, demonstrated by increased SFEMG jitter, and the enlargement of the motor unit, as indicated by increased fiber density, increased macro EMG signals, and fiber type grouping on muscle biopsy. However, there was no correlation between any of these parameters and the presence or absence of new symptoms of weakness. These findings suggest that impaired neuromuscular transmission is most common in patients with prior poliomyelitis whose motor units have been maximally enlarged by axonal sprouting, but is independent of the presence or absence of new symptoms of weakness. 相似文献
38.
The afferent nervous supply to the thymus gland has been investigated by means of the retrograde transport of horseradish peroxidase. It has been shown that the thymus receives an afferent supply from the nodose ganglia of the vagus and from the dorsal root ganglia C1–C7. The afferent innervation of the right and left thymic lobes is bilaterally organized; the fibers of a small celled population of nodose ganglion neurons cross outside the thymus and those of a larger celled population cross within the thymus gland. The functional implications of these findings are discussed in the context of central nervous system-immune system interactions. 相似文献
39.
J De Reuck I Claeys S Martens Ph Vanwalleghem G Van Maele R Phlypo H Hallez 《European journal of neurology》2006,13(4):402-407
It is not well established whether seizures and epilepsy after an ischaemic stroke increase the disability of patients. Seventy-two patients with delayed seizures after a hemispheric infarct (37 with a single seizure and 35 with epilepsy) were included in the study. The modified Rankin scale was used to compare disability of the patients at 1 month after stroke and at 2 weeks after single or the last seizure, in case of epilepsy. The size of the X-ray hypoattenuation zone was compared on computed tomographic (CT) scans, performed in the weeks after the stroke and 1 week after single or repeated seizures. Lesion size was determined by superimposing the CT slices on digital cerebral vascular maps, on which the contours of the infarct area were delineated. The extent of the infarcts was expressed as the percentage fraction of the total surface area of the cerebral hemisphere. Groups with a single seizure and with epilepsy were mutually compared. Infarcts predominated in the parieto-temporal cortical regions. In the overall group the median Rankin score worsened significantly after seizures. The average size of the X-ray hypoattenuation zone was also significantly increased on the CT scans after the seizures, compared with those after stroke, without clear evidence of recent infarction. Mutual comparison of patients with a single seizure episode and of those with epilepsy showed only a trend of more severe disability and of increase in lesion size in the post-stroke epilepsy group. Delayed seizures and epilepsy after ischaemic stroke are accompanied by an increase in lesion size on CT and by worsening of the disability of the patients. This study does not allow to determine whether this is due to stroke recurrence or due to additional damage as a result of the seizures themselves. 相似文献
40.
外伤后癫痫大鼠模型脑内铁蛋白与转铁蛋白含量的动态变化研究 总被引:1,自引:0,他引:1
目的:从脑内铁代谢的角度研究铁在外伤后癫(PTE)发病机制中的可能作用。方法:用ELISA方法检测PTE大鼠模型脑组织内铁蛋白(Ft)和转铁蛋白(Tf)的动态含量。结果:早期Ft在整个脑组织内呈现为即刻反应性升高,15d后其含量在实验对侧脑组织内恢复至正常范围,而在实验侧脑组织内呈现继续升高的趋势;Tf含量只在实验侧脑组织内升高,且呈现随时间继续升高趋势。结论:PTE大鼠模型中的铁代谢过程十分复杂,相关蛋白尤其是Tf含量的增加提示铁可能是外伤后癫灶形成机制的一部分。 相似文献