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31.
In this study we investigated the extent and time course of neuronal cell death and the regulation of the proliferating cell nuclear antigen (PCNA) in the different retinal cell layers following ischemia-reperfusion injury. Retinal ischemia was induced by controlled elevation of the intraocular pressure for a duration of 60 min. Changes in thickness and cell numbers in the retinal cell layers were analyzed at various time points (1 h to 4 weeks) after reperfusion. In parallel, apoptotic cell death was determined by the TUNEL method and the expression of PCNA analyzed by immunocytochemistry. In addition, we tested whether PCNA is expressed in neurons by double immunocytochemistry. The reduction in thickness was found to be less pronounced in the inner nuclear layer (INL). Correspondingly, cell numbers decreased by only 33% in the inner retina, but by more than 80% in the outer nuclear layer (ONL). Alterations in glial cell numbers did not contribute significantly to postischemic changes in the INL and ONL as assessed by using immunocytochemical markers for microglial and Müller cells. The time course of cell death determined by the TUNEL technique also differed markedly in the retinal layers being rapid and transient in the inner retina but delayed and prolonged in the ONL. PCNA immunoreactivity was undetectable in the normal retina, but was specifically induced in neurons of the inner retina within 1 h after reperfusion and was sustained for at least 4 weeks. We conclude that in contrast to photoreceptors in the ONL, a significant proportion of inner retinal neurons is resistant to ischemic insult induced by transiently increased intraocular pressure and that PCNA may possibly play a role in the selective postischemic survival of these cells.  相似文献   
32.
路菊 《现代医药卫生》2003,19(6):668-669
目的:探讨经鼻持续气道正压通气(nCPAP)治疗,对阻塞性睡眠呼吸暂停综合征(OSAS)合并高血压患者动态血压的影响。方法:22例男性患者行多导睡眠图(PSG)监测及动态血压检查确诊为OSAS合并高血压的患者,观察nCPAP治疗前后患者动态血压、多导睡眠图等多项指标变化。结果:nCPAP治疗后患者PSG参数明显改善:睡眠时最低SaO_2从(71.0±12.3)%上升到(91.7±7.3)%(P<0.01);RDI显著降低;同时24小时血压明显下降,治疗前血压(16.5±1.6/11.6±2.3Kpa),治疗后血压(13.7±1.5/9.3±1.4Kpa)(P<0.01)。结论:经鼻持续气道正压通气治疗阻塞性睡眠呼吸暂停综合征,不但可以纠正患者的呼吸暂停,改善临床症状,而且可能降低患者的血压。  相似文献   
33.
Yang T  Wu SL  Liang JC  Rao ZR  Ju G 《Neurosurgery》2000,47(2):407-15; discussion 415-6
OBJECTIVE: Using an experimental rat model and a clinically relevant treatment dose, we performed gamma knife radiosurgery to define the hyperacute radiation effects in normal rat forebrain, the time dependence of the astrocytic reaction, and the participation of astrocytes in the healing process after single-dose gamma radiation injuries. METHODS: Seventy-one rats underwent radiosurgical treatment (4-mm collimator) of the caudate-putamen nucleus (single-fraction maximal dose of 100 Gy) and were killed at times ranging from 3 hours to 90 days. Serial cryostat brain sections were processed with the immunohistochemical avidin-biotin complex technique, using anti-glial fibrillary acidic protein as the primary antibody (to identify astrocytes). RESULTS: Vascular changes, including endothelial hyperplasia and vessel wall thickening, were identified as the earliest postradiation manifestations and continued throughout the observation period. Astrocytes reacted to the radiation injury with hyperplasia and hypertrophy. At earlier time points (3-24 h), proliferation was the predominant reaction. The expression of glial fibrillary acidic protein in the proliferating and hypertrophic astrocytes formed an initial peak in the adjacent corpus callosum 3 days after radiosurgery and peaked within the target site between 14 and 30 days. Astrocytic proliferation and hypertrophy were also observed in distant cortices (frontal, parietal, insular, and piriform cortices) and in the hippocampus. No necrosis was observed less than 30 days after irradiation. By Day 90, necrotic lesions with a mean diameter of 4 mm were identified, with glial scar at their peripheries. Astrocytic morphological features varied according to the distance from the necrosis. The irradiated side contained more glial fibrillary acidic protein-containing cells than did the nonirradiated contralateral side. CONCLUSION: During the early phase after radiation, vasculopathy was the first morphological change and may serve as the initiating factor for subsequent changes. Reactive astrocytes appeared not only at the target site but also in the surrounding regions; the severity of injury was determined by the distance from the target.  相似文献   
34.
The existence of a vesical diverticulum in the context of a congenital connective tissue disorder such as Ehlers-Danlos syndrome led us to consider the possibility of a relationship. Four types of diverticula can be found in the literature: congenital, acquired, iatrogenic and syndrome-associated. Within the later, Ehlers-Danlos syndromes type IV and IX, even type V, are associated to the existence of vesical diverticula. The potential spontaneous rupture of the diverticulum is a typical feature, as well as post-surgery relapse. The attitude towards such diverticula should be one of watchful waiting, and simple, plasty-free diverticulectomy on the bladder's neck is indicated when performing a surgical procedure.  相似文献   
35.
36.
Cystic-glandular cystitis is considered as part of the urothelial pre-neoplastic proliferative abnormalities. This group includes atypical hyperplasia. Von Brunn's nidus, and cystitis cystica. They are a consequence of the changes experienced at the urothelium level in response to inflammation, irritation or carcinogens. Diagnosis is mainly based in the pathoanatomical study of the biopsy obtained following endoscopic resection. The signs and symptoms it presents are varied and show a clear relationship to distribution and extension of cysts. Treatment is based in the removal of irritative factors. Cystectomy with urinary by-pass may be necessary if required by clinical evolution.  相似文献   
37.
Clinical, radiographic (n = 5) and CT findings (n = 4) of five Korean infants ranging in age from 2 to 3 months with confirmed tuberculosis were retrospectively analysed. All of the patients were symptomatic, anergic to tuberculin, and had a positive culture of Myobacterium tuberculosis in gastric aspirates. The probable source of infection was the hospital in which they were born. CT scans demonstrated hilar and mediastinal lymph node enlargement with central low attenuation and peripheral enhancement in all cases. CT may be useful in diagnosis by demonstrating characteristic adenopathy and disseminated disease in young infants. Received: 2 September 1997 Accepted: 23 April 1998  相似文献   
38.
本室以往的研究表明,用腺病毒作为载体将大肠杆菌胞嘧啶脱氨酶(CD)基因与小鼠淋巴细胞趋化因子(Itn)基因联合体内转染,具有显著的抗肿瘤效应.本文对其免疫机理进行了进一步研究,发现CT26结肠腺癌细胞体外经过CD/Ltn基因转染并给予前体药物5-FC后,CT26结肠腺癌细胞表达CD80和CD54分子明显增加,提示经CD自杀基因和Ltn基因联转移后,肿瘤细胞免疫原性增加.荷瘤小鼠体内经联合治疗后,小鼠脾细胞分泌IL-2和IFN-γ明显增加.体内用抗CD4、CD8抗体阻断实验研究结果的表明,联合应用自杀基因和Ltn基因治疗主要通过诱导CD8~ T细胞发挥抗肿瘤作用.  相似文献   
39.
To investigate a potential role of ciliary neurotrophic factor (CNTF) in transient global ischemia, we have studied the postischemic regulatory changes in the expression of CNTF and its receptor, the ligand-binding alpha-subunit (CNTFRalpha). Immunoblot analysis demonstrated CNTF levels were slightly upregulated already during the first day after ischemia and then increased markedly by more than 10-fold until 2 weeks postischemia. Immunoreactivity for CNTF became detectable 1 day after ischemia and was localized in reactive astrocytes. The intensity of the immunolabeling was maximal in CA1 during the phase of neuronal cell death (days 3-7 postischemia) and in the deafferented inner molecular layer of the dentate gyrus. Upregulation of CNTF expression was less pronounced in CA3 and absent in the stratum lacunosum moleculare and the outer molecular layer of the dentate gyrus and thus did not simply correlate with astroliosis as represented by upregulation of glial fibrillary acidic protein (GFAP). As shown by in situ hybridization, expression of CNTFRalpha mRNA was restricted to neurons of the pyramidal cell and granule cell layers in control animals. Following ischemia, reactive astrocytes, identified by double labeling with antibodies to GFAP, transiently expressed CNTFRalpha mRNA with a maximum around postischemic day 3. This astrocytic response was most pronounced in CA1 and in the hilar part of CA3. These results show that CNTF and its receptor are differentially regulated in activated astrocytes of the postischemic hippocampus, indicating that they are involved in the regulation of astrocytic responses and the neuronal reorganizations occurring after an ischemic insult.  相似文献   
40.
[目的 ] 建立应用微流芯片检测甲 1型、甲 3型、乙型流感病毒多重逆转录聚合酶链反应 (mRT -PCR)产物的方法 ,在mRT -PCR扩增核酸的基础上自动化灵敏的定量检测扩增产物 ,快速检测甲亚型、乙型流感病毒 ,帮助临床快速诊断和鉴别诊断其他呼吸道病毒感染 ,以及明确流感病毒在人群中感染、流行情况。  [方法 ] 采用经MDCK细胞分离培养的甲 1型、甲 3型、乙型流感病毒毒株病毒液 ,使用 3组特异引物经mRT -PCR扩增核酸 ,扩增产物分别采用毛细管电泳技术经Caliper10 0 0微流芯片分析仪自动化检测和经 2 %琼脂糖凝胶电泳法检测。 [结果 ] 设计三组引物对相应甲 1型、甲 3型、乙型流感病毒靶基因的mRT -PCR扩增产物片段分别为 43 0bp、2 10bp、3 91bp ,本实验mRT -PCR扩增产物经 2 %琼脂糖凝胶电泳 ,与Marker比照 ,DNA条带基本在此位点附近 ;产物采用毛细管电泳法经Caliper10 0 0微流芯片分析仪后 ,分别于 413bp、2 0 3bp、3 79bp处出现陡峭的峰 ,如图所示。 [结论 ] 应用微流芯片采用毛细管电泳法可对流感病毒mRT -PCR产物进行定位及相对定量 ,有助于快速诊断流感病毒感染 ,有助于对流感的监测。  相似文献   
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