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51.
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   
52.
【目的】探讨脑梗死后再发缺血性卒中与脑出血患者的临床特点、影像学上微血管病变及预后的异同。【方法】连续收集急性复发性卒中的住院病例(初发事件为脑梗死,复发事件包括脑梗死或脑出血),详细记录临床资料。观察脑内微出血及自质病变的严重程度,随访有无严重血管事件及死亡的发生。【结果】175例再发脑梗死患者。19例复发事件为脑出血的患者进入本研究。155例(88.6%)再发脑梗死患者,以及18例(94.7%)脑出血患者存在自质病变。77例(44%)再发脑梗死患者和16例(84.2%)脑出血患者存在脑内微出血。脑出血组自质病变的严重程度及微出血的数目均明显高于再发脑梗死组(P=0.033,0.016),脑出血组的死亡率及再发脑出血的危险性明显增高(P=0.034,0.036)。【结论】严重的脑自质病变及微出血的出现与脑梗死后再发脑出血有关。多发微出血提示出血风险增高。如复发事件为脑出血,则其死亡率及再次复发脑出血的风险均明显增加。  相似文献   
53.
Sixty Sprague-Dawley rats were pair-fed one of three nutritionally identical diets. One diet contained “low-fiber” (3.8% crude fiber); the others contained “high fiber” (28.7% crude fiber) composed of either cellulose or lignin. Although both “high fiber” diets had similar stool bulking effects, only the cellulose diet was associated with a reduction in 1,2-dimethylhydrazine (DMH)-induced colon neoplasms. The cellulose diet was also associated with distinct changes in the gut bacterial profile and with a lowered serum cholesterol. © 1993 Wiley-Liss, Inc.  相似文献   
54.
Muscle fiber typing and in vitro contracture tests were performed in 59 patients investigated for susceptibility to malignant hyperthermia (MH). Eighteen patients were found to be susceptible to MH. There was no difference in age or fiber type distribution between MH susceptible and non-susceptible patients. No correlation was found between age and fiber type distribution. Separate analyses for each diagnostic group revealed no relationship between age or fiber type distribution and response to halothane or caffeine. When all caffeine results were pooled, however, there was a significant effect of age on the caffeine specific concentration (the concentration eliciting a contracture of 1 g), but not on the caffeine threshold concentration (the minimal concentration eliciting an increase in tension). It is concluded that age and fiber type distribution have no influence on MH diagnosis, if the protocol of the European MH Group for evaluation of susceptibility to MH is followed.  相似文献   
55.
Ma  K. -C.  Lundberg  P. O.  Lilja  A.  Olsson  Y. 《Acta neuropathologica》1992,83(4):434-439
Summary The cerebral changes are described in a woman of 54 who suffered from Binswanger's encephalopathy: there were no signs or symptoms of chronic arterial hypertension. The disease presented as dementia of about 3 years duration. Computed tomography of the brain 2. 5 years before her death showed bilateral widespread hypodense lesions in the cerebral white matter. She died of an asthmatic attack. Autopsy disclosed extensive bilateral degeneration of the central white matter, lacunes and gliosis. Severe obliterative arteriolosclerosis occurred in the meningeal vessels and those supplying the affected parts of the brain. Light microscopy showed that the most severe lesions occurred in the arterioles. Immunohistochemistry demonstrated profound extravasation of plasma proteins chiefly albumin, indicating dysfunction of the blood-brain barrier. Thus, the lesions characteristic of Binswanger's encephalopathy may develop in the absence of chronic arterial hypertension. Additional pathogenic factors, possibly genetic predisposition to vascular injury may play a role in the development of this condition.Supported by grants from the Swedish Medical Research Council, Project No 12X-03020 and 1987 Års Stiftelse för Strokeforskning  相似文献   
56.
通过对10例小儿及23例成年人的喉内肌进行的myosin-ATPase等染色观察,得到小儿和成人各喉内肌不同的肌纤维构成比。成人PCAⅠ型纤维最多,LCA、INA及CT次之,TA最少。小儿的各喉内肌也有类似比例。表明不论小儿或成人,PCA均具有较强的抗疲劳性,适应呼吸作用的需要;TA具有较快的收缩速度,以适应发声及呼吸道保护作用。从纤维构成上看,小儿与成人相比,各喉内肌Ⅰ型纤维较为匮乏,表明小儿的喉在发声及呼吸道保护等功能方面尚不够完善。  相似文献   
57.
玻璃纤维增强复合树脂在总义齿基托中的应用   总被引:1,自引:0,他引:1  
目的:增强总义齿基托的机械性能,提高总义齿的基托抗折裂能力。方法:对E-玻璃纤维用KH-550处理剂进行表面处理后,加入总义齿基托中,制成玻璃纤维增强复合树脂。结果:经过1年的临床观察后复诊,没有发现裂纹。结论:玻璃纤维增强得合树脂可以有效地增强总义齿基托的机械性能。  相似文献   
58.
Abstract: A 78-year-old male with renal carcinoma was treated with a high dose infusion of interferon-alpha (IFN-alpha) for eight months. The patient had evidence of organlc brain syndrome such 88 : dysfunction of memory, slowing of behavior, and development of mental confusion that appeared eight months after the treatment. MRI at the time of mental confusion revealed difise white matter lesions. Neuropathologic findings were compatible to Binswanger's disease and Senile Dementia of Alzheimer Type (SDAT), Preexisting neurologic abnormalities including intracerebral arteriosclerosis and cerebral atrophy may increase susceptibility to unacceptably severe IFN neurotoxicity.  相似文献   
59.
BACKGROUND: Volumetric studies have reported reductions in the size of the corpus callosum (CC) in autism, but the callosal regions contributing to this deficit have differed among studies. In this study, a computational method was used to detect and map the spatial pattern of CC abnormalities in male patients with autism. METHODS: Twenty-four boys with autism (aged 10.0 +/- 3.3 years) and 26 control boys (aged 11.0 +/- 2.5 years) underwent a magnetic resonance imaging (MRI) scan at 3 Tesla. Total and regional areas of the CC were determined using traditional morphometric methods. Three-dimensional (3D) surface models of the CC were also created from the MRI scans. Statistical maps were created to visualize morphologic variability of the CC and to localize regions of callosal thinning in autism. RESULTS: Traditional morphometric methods detected a significant reduction in the total callosal area and in the anterior third of the CC in patients with autism; however, 3D maps revealed significant reductions in both the splenium and genu of the CC in patients. CONCLUSIONS: Statistical maps of the CC revealed callosal deficits in autism with greater precision than traditional morphometric methods. These abnormalities suggest aberrant connections between cortical regions, which is consistent with the hypothesis of abnormal cortical connectivity in autism.  相似文献   
60.
Propriospinal myoclonus (PSM) is a rare movement disorder characterized by involuntary spinal-generated muscular jerks that spread rostrally and caudally to other spinally innervated muscles. Most patients have no clear etiology, and conventional MRI of the spinal cord is generally normal. Here we report the use of magnetic resonance diffusion tensor imaging (DTI) and fiber tracking to detect tract-specific abnormalities in a patient with propriospinal myoclonus. As the patient had the fragile-X premutation and antithyroid antibodies, spinal cord DTI abnormalities may be related to these conditions. Tract-specific analysis may provide new insights into the pathophysiology of propriospinal myoclonus.  相似文献   
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