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91.
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Involvement of precerebellar nuclei in multiple system atrophy   总被引:7,自引:0,他引:7  
In this semiquantitative study based on 26 post-mortem cases, we describe the involvement of precerebellar nuclei in multiple system atrophy (MSA), a progressive degenerative disorder of the human central nervous system characterized by abnormal, argyrophilic and alpha-synuclein immunopositive intracellular inclusions within selectively vulnerable oligodendrocytes and nerve cells. The Campbell-Switzer silver-pyridine technique with alpha-synuclein immunoreactions using 100-microm thick sections is recommended over more conventional methods, thereby permitting visualization of the pertinent lesions in greater detail and facilitating post-mortem diagnosis of MSA specimens. Affected oligodendrocytes occur in specific fibre tracts and grey matters, with most pathology being observed in projections from the precerebellar nuclei to the cerebellum (ponto-cerebellar, olivo-cerebellar, reticulo-cerebellar tracts) and in descending/ascending fibre tracts of the motor system (cortico-pontine, cortico-bulbar, cortico-spinal, spino-reticular, spino-olivary, spino-cerebellar tracts). Three types of abnormal intraneuronal aggregations occur: (i) a loosely woven network within the cell nucleus; (ii) a latticework accumulating in peripheral portions of the cell body; and (iii) irregularly outlined patches of compact, intensely argyrophilic material usually located within deposits of lipofuscin granules. Counter-staining for the presence of extraneuronal lipofuscin can aid neuropathologists in the recognition of lost existent neurones in MSA. Neurones with inclusion bodies occur in the inferior olivary nuclear complex, lateral reticular nucleus, external cuneate nucleus, conterminal nucleus, interfascicular nucleus, nucleus of Roller, dorsal paramedian reticular nucleus, subventricular nucleus, arcuate nucleus, pontobulbar body and pontine grey. The lateral reticular nucleus and accessory nuclei of the inferior olive sustain the most damage and reveal prominent neuronal loss, followed by the pontobulbar body and arcuate nucleus. The uniformly bilateral damage and, in some cases, even obliteration of the nuclei studied, supply additional evidence for the pathoanatomical substrata of the cerebellar dysfunction that reportedly emerges in the clinical course of MSA.  相似文献   
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Ethmoid adenocarcinomas: retrospective study of 76 patients   总被引:2,自引:0,他引:2  
From the retrospective study of 76 adenocarcinomas of the ethmoid sinuses, results were expressed in two terms: the morbidity related to surgery and the oncologic outcome. This case study extends between 1975 and 2000. It includes 71 men and 5 women, with an average of 61 years. 81% of them works in wood dust, with a mean duration of exposure of 26 years. The diagnosis of adenocarcinoma is realized in the three months after the first signs, essentially rhinologicals, next neurologicals and ophthalmologicals. The majority of tumors were classified as T3N0M0, i.e. 57.89%. The treatment of this tumors is surgical: 34.2% surgical only and 59.2% with radiotherapy. The transfacial approach (paralateronasal and degloving) and the combined surgery are respectively performed in 36 patients and 35 patients. 23.2% patients had a local recurrence, and 10% developed cervical nodes and systemic metastasis. Survival rate based on the Kaplan-Meier actuarial method is 82% at 3 years, 80% at 5 years, 72% at 10 years. The prognosis of ethmoidal cancer is strictly correlated to local control. Local recurrence is statistically more likely in patients with involvement of the dura, brain and sphenoid sinus. With the analysis of the carcinologics results, we discuss the therapeutics indications of the adenocarcinomas and a new classification. Taking in account the involvement of the dura, sphenoid and orbit. We did not find any statistical differences between T3 patients treated by combined approach (n = 13) or by transfacial approach (n = 15).  相似文献   
95.
Background: Pouch development is a potentially serious problem following gastric banding, and re-operation is often demanded to maintain long-term function of the lap band. Laparoscopic gastric banding was performed with two different calibrations of the pouch. Within a period of 12 months, postoperative pouch behavior with regard to volume and shape was evaluated retrospectively, as were changes in the distal esophagus. Methods: The pouches of 14 patients with intraperitoneal band positioning were calibrated at 25 ml. The volumes of 54 patients operated by a suprabursal technique were set at 15 ml. We performed three radiological examinations and calculated the volumes using the ellipsoid formula d1 x d2 x d3 x π/6. Four morphologically different pouch types have been observed: regular, concentric, eccentric-medial and eccentric-lateral. The ϕ-angle corresponds to the angle between the spinal column and the gastric band. Results: In the first group, the pouch volume increased from 21.2 ml ± 21.2 to 87.9 ml ± 64.6 (p=0.006) and the BMI fell from 47.1 kg/m2 ± 8.4 to 38.1 kg/m2 ± 7.0 (p=0.001). The pouch volume of the second group increased from 10.4 ml ± 5.8 to 38.8 ml ± 29.1 (p<0.001), and the BMI reduced from 48.4 kg/m2 ± 6.9 to 39.3 kg/m2 ± 6.7 (p<0.001). If the ϕ-angle is smaller than 4°,the pouch is of the eccentric-medial type. Conclusions: The transbursal operative technique is responsible for the development of the eccentric-medial pouch. If the anterior sero-muscular fixative sutures tear, an eccentric-lateral pouch results. All pouch types are affected by changes at the pouch-esophageal junction and by pathological developments in the distal and middle oesophagus.  相似文献   
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目的构建人同种异体移植炎症因子-1(allograft inflammatory factor-1,AIF-1)基因的真核表达载体并在小鼠成纤维细胞系(NIH3T3)中表达,为进一步研究AIF-1蛋白的功能奠定基础。方法利用基因重组技术,构建带有AIF-1基因的2种重组真核表达载体:pcDNA3.1(-)/AIF-1与pEGFP-C1/AIF-1。利用脂质体法将2种重组质粒分别转染NIH3T3细胞,用荧光倒置显微镜及Western blot方法观察及鉴定AIF-1在细胞中的稳定表达及瞬时表达。结果酶切分析及DNA序列测定证实,AIF-1基因片段被分别克隆入真核表达载体pcDNA3.1(-)与pEGFP-C1。荧光显微镜观察到NIH3T3细胞中有绿色荧光分布。Western blot结果表明,转染重组质粒的NIH3T3细胞中,AIF-1表达量明显增高。结论成功构建了2种重组真核表达载体:pcDNA3.1(-)/AIF-1与pEGFP-C1/AIF-1,经转染NIH3T3细胞株获得了AIF-1蛋白的瞬时表达及稳定表达。  相似文献   
98.
In order to improve therapy and increase the quality of life for diabetic patients, it has been of significant interest to develop rapid-acting insulin preparations that mimic the physiological meal-time profile of insulin more closely than soluble human insulin. Insulin aspart (B28Asp human insulin) is a novel rapid-acting insulin analogue that fulfils this criterion. The B28Asp modification weakens the self-association of the insulin molecule and provides a more rapid absorption from the sc. injection site. The preclinical evaluation in vitro and in vivo demonstrates that apart from the more rapid absorption, insulin aspart is equivalent to human insulin. Thus, insulin aspart is equivalent to human insulin on key in vitro parameters such as insulin receptor affinity, insulin receptor dissociation rate, insulin receptor tyrosine kinase activation, IGF-I receptor binding affinity, metabolic and mitogenic potency. In accordance with the equivalent in vitro profiles, the toxico-pharmacological properties of insulin aspart and human insulin are also identical. The available data for insulin aspart and other rapid-acting insulin analogues supports that in vitro assays are sensitive and valuable in the preclinical evaluation of insulin analogues. Clinical studies demonstrate that insulin aspart has a pharmacokinetic and pharmacodynamic profile superior to that of soluble human insulin. In Type 1 diabetic patients on a basal-bolus injection regimen, insulin aspart given immediately before the meals provides an improved postprandial glycaemic control and an improved long-term metabolic control, as compared to soluble human insulin given 30 min before the meals, without increasing the risk of hypoglycaemia. Taken together, the data support the hope that insulin aspart will allow the diabetic patient to combine a more flexible lifestyle with better glycaemic control, without any increased safety risk.  相似文献   
99.
目的 分析胆道术后严重出血的临床病程和治疗效果。方法 回顾性分析2016-2018年海军军医大学附属东方肝胆外科医院胆道外科行手术治疗的胆道疾病病人中需要行介入治疗(内镜和血管造影治疗)或再次手术的严重大出血者54例临床资料。结果 胆道术后严重出血的发生率为1.7%(54/3183)。胆道术后严重出血相关的总体死亡率为0.53%(17/3183)。54例病人中,有3例行内镜检查,仅1例行内镜治疗成功止血;34例接受介入血管造影检查的病人中,23例接受了介入性栓塞治疗(包括介入性钢圈栓塞、覆膜支架等血管介入治疗),18例止血成功,成功率为78.3%(18/23)。35例行再次剖腹止血手术,其中19例将手术作为一线治疗方案,16例为内镜或介入治疗失败后行补救性治疗。结论 胆道术后严重出血原因较多,临床表现多样,早期发现和治疗至关重要。应综合考虑发病时间、伴发并发症情况和初次手术方案制定治疗决策。介入治疗临床安全性和止血成功率较高,但在介入治疗止血失败的情况下应紧急中转手术治疗。  相似文献   
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