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91.
Astrocytes, with their many functions in producing and controlling the environment in the brain, are of great interest when it comes to studying regeneration after injury and neurodegenerative diseases such as in grafting in Parkinson's disease. This study was performed to investigate astrocytic guidance of growth derived from dopaminergic neurons using organotypic cultures of rat fetal ventral mesencephalon. Primary cultures were studied at different time points starting from 3 days up to 28 days. Cultures were treated with either interleukin-1 beta (IL-1 beta), which has stimulating effects on astrocytic proliferation, or the astrocytic inhibitor cytosine arabinoside (Ara-C). Tyrosine hydroxylase (TH)-immunohistochemistry was used to visualize dopaminergic neurons, and antibodies against glial fibrillary acidic protein (GFAP) and S100 beta were used to label astrocytes. The results revealed that a robust TH-positive nerve fiber production was seen already at 3 days in vitro. These neurites had disappeared by 5 days. This early nerve fiber outgrowth was not guided by direct interactions with glial cells. Later, at 7 days in vitro, a second wave of TH-positive neuritic outgrowth was clearly observed. GFAP-positive astrocytic processes guided these neurites. TH-positive neurites arborized overlying S100 beta-positive astrocytes in an area distal to the GFAP-positive astrocytic processes. Treatment with IL-1 beta resulted in an increased area of TH-positive nerve fiber network. In cultures treated with Ara-C, neither astrocytes nor outgrowth of dopaminergic neurites were observed. In conclusion, this study shows that astrocytes play a major role in long-term dopaminergic outgrowth, both in axonal elongation and branching of neurites. The long-term nerve fiber growth is preceded by an early transient outgrowth of dopamine neurites.  相似文献   
92.
同型半胱氨酸对胚胎海马神经元细胞的影响   总被引:1,自引:1,他引:0  
目的 观察同型半胱氨酸(homocysteine,HCY)对海马神经元细胞分化和增殖的作用机理。方法 采用大鼠胚胎海马神经元细胞进行体外培养。观察不同浓度的HCY(0.01、0.1、1.0、10.0、100.0)mmol/L对细胞分化和增殖的影响。结果 随着剂量的增加.同型半胱氨酸对胚胎海马神经元细胞分化和增殖具有抑制作用,并用流式细胞术分析证明对脂质过氧化(LPO)的影响而使得神经元蛋白质含量增高。结论 同型半胱氨酸可抑制胚胎海马神经元细胞分化和增殖的影响,HCY可能在导致神经管畸形的过程起着重要作用。  相似文献   
93.
Swabbing the urethrae of men has been the traditional approach for collecting specimens for detection of Chlamydia trachomatis . Recently, however, urine testing using enzyme immunoassay has yielded promising results. A total of 105 patients attending the Andrology Clinic at Ga Rankuwa Hospital, Medunsa were included in the study. These patients were asymptomatic and had no urethral discharge. Three endo-urethral swabs and first-catch urine were collected fiom each patient. The urethral swabs were used for enzyme immunoassay (EIA) (IDEIA 111), tissue culture and direct immonufluorescent antibody (DFA) test (IMAGEN) to detect C. trachomatis . In addition about 15–30 ml of first-catch urine, or urine collected at least 2h after the previous micturition, was collected for each patient for EIA testing. Fifteen (14.3%) of 105 patients were positive on urethral swab EIA, in comparison with the DFA test in which 14 (13.3%) were positive. Eight (7.8%) were positive in tissue culture. Urine EIA was positive in 17 (16.2%) patients, of whom five (4.8%) were positive in urine EIA only. All EIA positive urines were confirmed by DFA. We recommend that first-catch urine or urine collected at least 2h after the previous micturition in infertile males may be considered a suitable alternative to urethral swab for chlamydial diagnosis because it is noninvasive and nontraumatic.  相似文献   
94.
目的 :探讨ATP敏感性K+ 通道 (KATP)开放剂吡那地尔 (pinacidil,Pin)对缺氧缺糖再复氧损伤大鼠大脑皮层神经细胞的保护作用。方法 :体外培养大鼠大脑皮层神经细胞 ,细胞培养至 10d ,建立神经细胞缺氧缺糖损伤模型 ,观察Pin及KATP阻断剂格列苯脲对缺氧缺糖不同时间 ,再复氧 2 4h后细胞死亡率、丙二醛 (MDA)含量、超氧化物歧化酶 (SOD)活力的影响。结果 :缺氧缺糖、再复氧后大鼠的神经细胞死亡率均显著升高、MDA生成增多、SOD的活力下降 ,Pin干预后 ,细胞死亡率下降、MDA生成减少、SOD的活力升高 ;格列苯脲能拮抗Pin这种保护作用。结论 :Pin对缺氧缺糖损伤神经细胞具有保护作用 ,并与拮抗氧自由基有关  相似文献   
95.
从1例膀胱癌患者的癌组织培养中,分离得到2个不同生长特性的悬浮生长型细胞系,定名为TSB-90和TSB-91。在培养过程中,对其生物学特性进行了细胞和亚细胞水平的探讨,并进行了核型分析。发现2个细胞系核型的演化趋势有明显差异,生物学特性也不尽相同。这可能与膀胱癌组织中细胞的遗传异质性和分化程度有关。对其机制和细节有待进一步深入研究。  相似文献   
96.
Mammalian neurons from ventral mesencephalon (VM) were grown in primary dissociated cell (PDC) culture. These neurons are predominantly non-dopaminergic. Many of these non-dopaminergic neurons have dopamine agonist and antagonist binding sites. Intracellular recordings were obtained from these neurons. When bathed in phosphate-buffered saline (PBS) solution they generated action potentials spontaneously. However, in the presence of haloperidol dissolved in PBS solution, the percentage of neurons which generated action potentials spontaneously was reduced in a dose-dependent manner (1–10 μM). This response was also obtained with (+) butaclamol (1 μM) but not with (−) butaclamol (1 μM). This neuroleptic inhibition of spontaneously generated action potentials was specific for neurons in PDC cultures of VM since neurons in PDC cultures of spinal cord did not demonstrate this phenomenon.  相似文献   
97.
对构建特色医院文化的思考   总被引:3,自引:1,他引:2  
李泽平 《中国医院》2002,6(12):10-12
21世纪的医院是文化的医院,21世纪医院的竞争是文化的竞争,谁能构建出具有特色的医院文化,谁就能赢得竞争主动权。构建特色医院文化,核心是形成共同的理想和精神支柱;关键是打造“学习型”医院组织;根本是树立以人为本、诚信求实的服务理念;目标是树立良好的医院形象;基础是加快医院信息化建设。  相似文献   
98.
骨髓间充质干细胞的分离培养及生物学特性研究   总被引:3,自引:0,他引:3  
目的:通过体外细胞的培养方法将骨髓间充质干细胞由骨髓血中分离出来并加以纯化,进一步在体外培养条件下研究其增殖及生长特征,从而为探讨后续利用组织工程学方法修复肌肉骨骼系统组织缺损的可能性提供实验基础。方法:从骨髓血中提取间充质干细胞,体外培养扩增,再以相差显微镜、电镜观察并绘制生长曲线。结果:(1)通过离体培养,可以使体内环境下低丰度的骨髓间充质干细胞实现数目扩增。(2)体外培养条件下骨髓间充质干细胞具有成纤维细胞的生长特性。(3)体外单层培养条件下贴壁生长的骨髓间充质干细胞会出现“返祖现象”。(4)骨髓间充质干细胞内细胞器与其生物活性变化相一致。结论:骨髓间充质干细胞体外培养成功为今后利用自体间充质干细胞通过组织工程学方法修复肌肉骨骼系统的组织缺损提供功能细胞奠定了基础。  相似文献   
99.
We have investigated the relative contributions of oxygen and glucose deprivation to ischaemic neurodegeneration in organotypic hippocampal slice cultures. Cultures prepared from 10-day-old rats were maintained in vitro for 14 days and then deprived of either oxygen (hypoxia), glucose (hypoglycaemia), or both oxygen and glucose (ischaemia). Hypoxia alone induced degeneration selectively in CA1 pyramidal cells and this was greatly potentiated if glucose was removed from the medium. We have also characterised the effects of both pre-and post-treatment using glutamate receptor antagonists and the sodium channel blocker tetrodotoxin (TTX). Neuronal death following either hypoxia or ischaemia was prevented by pre-incubation with CNQX, MK-801 or tetrodotoxin. MK-801 or CNQX also prevented death induced by either hypoxia or ischaemia if added immediately post-insult, however, post-insult addition of TTX prevented hypoxic but not ischaemic damage. Organotypic hippocampal slice cultures are sensitive to both NMDA and non-NMDA glutamate receptor blockade and thus represent a useful in vitro system for the study of ischaemic neurodegeneration paralleling results reported using in vivo models of ischaemia.  相似文献   
100.
人脐血中血管内皮祖细胞体外扩增和鉴定的实验研究   总被引:7,自引:0,他引:7  
目的:探讨从人脐血中分离、培养、体外扩增血管内皮祖细胞(EPC)的方法及体外进行EPC的鉴定。方法:采用密度梯度离心法从脐血中分离EPC,体外分别培养在包被有FN和不包被FN的培养皿中,采用免疫组织化学技术(SABC法)鉴定培养贴壁细胞表面标志CD31、CD34及KDR的表达;流式细胞仪检测细胞表面标志CD133及表达CD133细胞比例。结果:包被FN的培养皿中细胞贴壁及增殖均比未包被的多,免疫组化染色CD31、CD34及KDR均呈阳性,培养第4天流式细胞仪检测CD133^ 占21.3%。结论:密度梯度离心法可用于体外分离脐血中EPC进行实验研究,FN对于体外培养EPC有非常重要的作用。  相似文献   
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