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21.
Summary Ultrastructural and tracer studies have demonstrated that vasogenic edema, a serious complication of brain tumor is the result of increased permeability of tumor vessels. However, not much information is available on the alterations in the vessels in the peritumoral areas. Therefore, we studied the ultrastructural changes in the tumor micro-blood vessels (MBVs) in 20 cases of glioma and compared these with the changes in the peritumoral MBVs in 10 of these cases.The tumor MBVs showed remarkable structural changes, viz, increase in pinocytotic vesicles, large vacuoles and microvilli in the endothelial cells, varying degrees of endothelial attenuation and fenestration, an occasional partially or completely opened-up junction and some pale and edematous endothelial cells, which can adequately explain their increased permeability.The peritumoral MBVs also showed evidence of increased permeability in the form of increased pinocytotic vesicles, large vacuoles and microvilli associated with pale and edematous cytoplasm of some endothelial cells. Thickened multilayered basement membrane, absence of ensheathment of capillary basement membrane by astrocytic cell processes and widened perivascular space were observed in both tumoral and peritumoral MBVs.An interesting observation was that in the peritumoral MBVs, the pinocytotic vesicles were most conspicuously seen on the abluminal side of the endothelial cells often fused with the abluminal plasma membrane. Although a static study like this cannot indicate any definite direction of movement of fluid, we feel that the occurrence of reverse pinocytosis is a distinct possibility in the peritumoral MBVs and that it may be an important means of resorption of edema fluid.  相似文献   
22.
复发性口腔溃疡患者血Cu,Fe,Zn含量分析   总被引:5,自引:0,他引:5  
目的:探讨微量元素在复发性口腔溃疡发病中的作用。方法:检测了44例复发性口腔溃疡患者血清微量元素Cu,Fe,Zn含量,并与正常健康人对照,统计结果用t检验。结果:复发性口腔溃疡患者血清Zn含量明显低于对照组,而Fe含量高于对照组。结论:提示缺Zn是诱发复发性口腔溃疡的因素之一。  相似文献   
23.
甲状腺手术显露喉返神经的临床研究   总被引:6,自引:2,他引:4  
目的探讨甲状腺手术时显露喉返神经(RLN)对预防RLN损伤的作用。方法分析810例甲状腺手术中252例甲状腺手术中显露RLN(甲组)和558例术中未显露RLN(乙组)患者的临床资料。结果虽然甲组甲状腺手术切除范围大于乙组;但甲组RLN损伤发生率(1.19%)明显低于乙组(3.05%)(P<0.01)。结论甲状腺手术时有选择地显露喉返神经,可明显降低喉返神经损伤发生率。  相似文献   
24.
喉返神经解剖在甲状腺手术中的应用研究   总被引:4,自引:0,他引:4  
目的探讨解剖喉返神经在甲状腺手术中的应用。方法回顾分析因甲状腺疾病行手术治疗的236例患者的临床资料,共施行甲状腺手术335侧次;甲组101例行甲状腺手术158侧次,术中均未解剖喉返神经,其中57例行双侧甲状腺手术。乙组135例行甲状腺手术同时解剖喉返神经177侧次,其中42例因双侧甲状腺手术而行双侧喉返神经解剖。结果喉返神经损伤均发生在切除甲状腺范围包含背侧腺体时。甲组暂时性损伤2例,永久性损伤1例,损伤率为1.9%;乙组暂时性损伤1例,无永久性损伤病例,损伤率为0.56%;两组差异有统计学意义(χ2=0.382,P<0.01)。结论甲状腺手术中解剖喉返神经能减少喉返神经的损伤,切除背侧腺体时应常规解剖喉返神经。  相似文献   
25.
复发性胶质瘤再手术治疗的探讨   总被引:2,自引:0,他引:2  
目的 探讨复发性胶质瘤患者再手术的效果。方法 对22例复发性胶质瘤患者再手术前的功能状态、两次手术间隔时间及手术切除的程度与术后存活期等资料进行临床和统计学分析。结果 第二次手术前生活能自理或半自理的病人(Kamofsky计分≥60)平均生存期约16月,生活不能自理的病人(Kamofsky计分〈60)平均生存期约6月(P〈0.01)。两次手术间隔时间大于1年者平均生存期约17月,间隔时间小于半年者平均生存期约6月(P〈0.01)。手术肿瘤全切除者平均生存期约15月,次全切除者平均生存期约10月(P〈0.05)。结论 术前功能情况好,手术间隔时间大于1年及术中全切肿瘤者再手术治疗可获得较好效果。  相似文献   
26.
甲状腺手术中避免喉返神经损伤的实用解剖研究   总被引:3,自引:0,他引:3  
对20例单发良性甲状腺瘤手术进行了动态解剖学观察,主要针对侧叶切除术中喉返神经的有关解剖学关系进行测量分析,对术中处理甲状腺下动脉的方法提出与传统观念不同的意见认为术中游离并托起患侧叶,紧贴腺体切断甲状腺下动脉各分支,保留甲状腺下动脉主干的方式是避免喉返神经损伤的有益方式  相似文献   
27.
It has been reported that the clinical and electroencephalographic profiles of zolpidem, a non-benzodiazepine drug which binds preferentially to the ω1 benzodiazepine recognition sites located within the GABAA receptor complex, are different from those of benzodiazepine drugs, which bind non-selectively to the ω1 and ω2 sites. In order to clarify the electrophysiological mechanism underlying the unique profile of zolpidem, the present study compared the enhancing effects of zolpidem and two benzodiazepine drugs, triazolam and diazepam, on recurrent inhibition. This inhibition was expressed as suppression of the orthodromically induced population spikes by the preceding antidromic stimulation of the alveus in the CA1 region of rat hippocampal slices. The rank order of potency for enhancing recurrent inhibition was triazolam > diazepam > zolpidem. From the present results and previously reported findings that zolpidem has a lower affinity for the ω2 sites than diazepam while both have the same affinity for the ω1 sites, we concluded that the hippocampal recurrent inhibition appears to be enhanced mainly by activation of the ω2 sites, but not by that of the ω1 sites. Furthermore, the lower potency of zolpidem for enhancing recurrent inhibition may underlie its unique profile in terms of its clinical and electroencephalographic effects. Received: 1 November 1996/Final version: 22 January 1997  相似文献   
28.
The development and maintenance of the normal functional integrity of the mammalian central nervous system is under the influence of a number of growth and trophic factors. One such growth factor, epidermal growth factor, has been detected in the mammalian brain and found to be associated with various brain regions and cell types. This small ubiquitous polypeptide can influence the proliferation, Metabolism, and differentiation of both glia and neurons in the central nervous system. We discuss the effects of epidermal growth factor on glial and neuronal cell function in an attempt to understand its role in development and maintenance of normal brain integrity. In addition, we review its possible implications in several pathological states in the central nervous system and speculate on therapeutic applications for this growth factor. © 1992 Wiley-Liss, Inc.  相似文献   
29.
Summary During a period of 17 years (from 1976 till now) 45 patients with giant gliomas of the chiasma and the IIIrd ventricle out of a total amount of 120 patients with hypothalamic gliomas were operated. The following classification of tumours was used: I) tumours with predominant anterior growth; II) tumours which infiltrate chiasma and penetrate into the IIIrd ventricle; III) gliomas of the floor of the IIIrd ventricle and the chiasma, growing into the ventricle cavity; IV) tumours of the chiasma, optic tract and thalamus. The authors come to the conclusion, that surgical removal of giant tumours of the chiasma and the IIIrd ventricle, though risky, may result in an improvement or stabilisation of visual functions (77%) and a long period free from recurrencies (9.5%). The postoperative period is relatively favourable and the mortality is low (6%). The main contraindication in our opinion is a wide infiltration of adjacent brain structures by the tumour and spreading along both optical tracts. We consider the giant size of a tumour in itself a sufficient indication for surgery.  相似文献   
30.
We have performed molecular and mutation analyses on 14 unrelated Israeli Hunter families and have identified the IDS mutation in 8 of them. Three unrelated Ashkenazi patients had the same previously reported mutation (1246 C→T). Based on the haplotypes of the mutation-bearing chromosomes, we concluded that this is a recurrent mutation. In two patients, we identified a deletion spanning exons V–VII. Three novel mutations were observed in different patients: L410P, 717del4, and 244del3. In addition, the silent mutation (562 C→T) was observed in one patient. © 1994 Wiley-Liss, Inc.  相似文献   
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