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41.
R. N. KALARIA ‡‡ P. G. GALLOWAY† G. PERRY‡ ‡‡ 《Neuropathology and applied neurobiology》1991,17(3):189-201
Amyloid P (AP) component is present in all types of systemic amyloid deposits. Recently, it has been shown to be also present in cerebral amyloid lesions of Alzheimer's disease (AD). In this study, we used immunocytochemical methods to extend these findings at the electron microscope level and characterize the spectrum of AP immunoreactivity in neurofibrillary pathology (NFP) of AD and other neurodegenerative disorders including Down's syndrome (DS), Creutzfeldt-Jakob, Parkinson's, Pick's and diffuse Lewy body diseases and progressive supranuclear palsy. In AD and DS, AP immunoreaction product was evident in all the classical amyloid lesions and NFP in a large sample of all cortical areas examined. The distribution and relative intensity of immunostaining was similar to that of thioflavin S staining in serial sections. In many cases, however, plaques and vessels stained by anti-AP serum were not apparent with thioflavin S. Serial sections immunostained with antiserum to amyloid A, C-reactive protein or to other proteins involved in systemic amyloidoses and the acute phase response showed no evidence of staining in any of the cerebral lesions. Electron microscopy confirmed that AP immunoreactivity was associated with the abnormal filaments characteristic of NFP as well as amyloid fibrils found in plaques and vessels showing congophilic amyloid angiopathy. Plaques of Creutzfeldt-Jakob disease, Pick bodies of Pick's disease, tangles and Lewy bodies in Parkinson's disease and a subpopulation of Lewy bodies in the diffuse Lewy body disease coexistent with AD were also stained. With the exception of vessels in two of the five cases, AP was not detected in age-matched controls. Our observations indicate AP to be a consistent feature of cerebral NFP and amyloid deposits. 相似文献
42.
43.
The formation of the blood-testis barrier (BTB) in the domestic fowl was studied at the electronmicroscopic level employing lanthanum as a tracer. No effective barrier could be demonstrated in testes before puberty, although several components of the Sertoli junctional complex such as focal tight junctions and desmosomes were already existent. The time of onset of meiosis after hatching showed great individual variation and meiosis did not occur synchronously in the tubules of a given testis. An effective barrier could first be detected in tubules containing early spermatids, and in which spermatogonia and primary spermatocytes at the leptotene stage were still within the open compartment. Thus, barrier formation was correlated with the occurrence of haploid germ cells. Complete compartmentation of seminiferous tubules, leaving only spermatogonia within the open compartment, was attained in tubules containing elongated spermatids of the maturation phase. In these tubules, primary spermatocytes at the leptotene stage were situated in an intermediate compartment. 相似文献
44.
Chronic intestinal pseudo-obstruction: manifestations, natural history and management 总被引:2,自引:0,他引:2
v. stanghellini r. f. cogliandro r. de giorgio g. barbara b. salvioli & r. corinaldesi 《Neurogastroenterology and motility》2007,19(6):440-452
Chronic intestinal pseudo-obstruction (CIPO) is a rare pathological condition characterized by a marked derangement of gut propulsive motility mimicking mechanical obstruction, in the absence of any lesion occluding the gut lumen. This disease is often associated with a disabling and potentially life-threatening complications and is still too often unrecognized even in referral centres. As a result, patients receive neither appropriate care nor recognition of their severe health condition. Medical and surgical therapies are often unsatisfactory and long-term outcome turns out to be poor in the vast majority of cases. This article focuses on the main clinical features, the management and long-term outcome of patients affected by CIPO, with particular emphasis on those aspects which remain a matter of debate. 相似文献
45.
PT Foley A Ganeshan S Anthony R Uberoi 《Journal of Medical Imaging and Radiation Oncology》2010,54(1):9-16
This is a retrospective review of the results at our institution of using multi-detector CT angiography (CTA) to localise lower gastrointestinal (GI) bleeding. We hypothesised that in our patient population: (i) CTA was unlikely to demonstrate bleeding in patients who were haemodynamically stable; (ii) in haemodynamically unstable patients in whom CTA was undertaken, the results could be used to select patients who would benefit from catheter angiography; and (iii) in haemodynamically unstable patients in whom CTA was undertaken, a subgroup of patients could be identified who would benefit from primary surgical treatment, avoiding invasive angiography completely. A retrospective review was conducted of the clinical records of all patients undergoing CTA for lower GI haemorrhage at our institution between 1 January 2005 and 30 June 2007. Out of the 20 patients examined, 10 had positive CTAs demonstrating the bleeding site. Nine were haemodynamically unstable at the time of the study. Four patients with positive CT angiograms were able to be treated directly with surgery and avoided invasive angiography. Ten patients had negative CTAs. Four of these were haemodynamically unstable, six haemodynamically stable. Only one required intervention to secure haemostasis, the rest stopped spontaneously. No haemodynamically stable patient who had a negative CTA required intervention. CTA is a useful non-invasive technique for localising the site of lower GI bleeding. In our patient population, in the absence of haemodynamic instability, the diagnostic yield of CTA was low and bleeding was likely to stop spontaneously. In haemodynamically unstable patients, a positive CTA allowed patients to be triaged to surgery or angiography, whereas there was a strong association between a negative CTA and spontaneous cessation of bleeding. 相似文献
46.
A Alzahrani M Anvari B Dallemagne D Mutter J Marescaux 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2007,11(1):97-100
OBJECTIVE: We report on 3 patients who underwent laparoscopic antireflux procedures for persistent symptoms of GERD after biopolymer injection. METHODS: Experienced laparoscopic surgeons completed all 3 procedures laparoscopically. In 2 patients, there was an extramural extravasation of the polymer outside and adherent to the esophageal wall. In these patients, a partial posterior fundoplication was used. The third patient, who had the polymer material deposits removed preoperatively by endoscopic mucosal resection, underwent a Nissen fundoplication. RESULTS: Postoperative recovery was uneventful in all cases. At follow-up of 6 to 12 months, all patients were symptom free, off medical therapy, and experiencing no dysphagia. CONCLUSION: Surgical therapy for patients after failed biopolymer injection is safe and effective. The choice of surgery may depend on whether the polymer mass can be removed preoperatively. 相似文献
47.
血管内皮生长因子在高原脑水肿形成中作用的实验研究 总被引:4,自引:0,他引:4
目的:探讨血管内皮生长因子(VEGF)在高原脑水肿形成中的作用。方法:建立大鼠模拟高原模型,应用脑干湿重比率法定量脑水肿情况、应用荧光素钠透过率测定BBB通透性、应用实时荧光定量RT-PCR法检测脑组织VEGF mRNA含量以及应用蛋白印迹法半定量脑组织VEGF含量。结果:大鼠在高原24 h后脑组织含水率明显增高(P<0.05),荧光素钠透过率显著增加(P<0.01);VEGF mRNA转录及其表达显著增高(P<0.001)。结论:VEGF表达在高原脑水肿形成中起重要作用。 相似文献
48.
目的:探讨提高原发胃肠道淋巴瘤术前诊断率及治疗效果的方法。方法:对36例原发胃肠道淋巴瘤患者的临床表现、体征及辅助检查进行分析,通过COX回归等统计方法对其预后因素及生存率等进行分析。结果:该病临床表现无特异性;诊断主要依靠内窥镜病理活检;手术方式、综合治疗完成情况、临床分期为与预后有关的影响因素。结论:提高对该病临床表现及内镜、造影检查特点的认识,采用正确的活检方法是提高术前诊断率的关键;以手术及化疗为主的综合治疗措施是提高疗效的关键。 相似文献
49.
下消化道出血的少见病因 总被引:2,自引:0,他引:2
下消化道出血病因复杂,随着诊疗技术的发展,人们对一些少见病因有了越来越多的了解,现就部分少见病因作一综述,以帮助临床诊断与治疗. 相似文献
50.
鼻胃管胃肠减压在择期腹部手术中的应用价值 总被引:6,自引:0,他引:6
鼻胃管胃肠减压曾被常规应用于择期和急诊的腹部手术后,目的是预防急性胃扩张的发生、治疗梗阻、降低吻合口压力等。但是,鼻胃管置入也会带来一些副作用,如呼吸道并发症、胃-食道反流、体液和电解质的丢失、声带的损伤,以及越来越被重视的患者的不适感。近年来的研究结果也对择期的腹部手术后常规应用鼻胃管胃肠减压提出不同的看法。现重新评价应用鼻胃管胃肠减压的理论基础及相关临床研究的结果,并对鼻胃管胃肠减压在择期腹部手术中的价值作一综述。 相似文献