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81.
大鼠皮质神经元的体外培养和纯化   总被引:8,自引:2,他引:6  
目的:探讨大鼠皮质神经元分离纯化的有效方法。方法:取胎鼠大脑皮质细胞,分别在不同的培养液中进行原代培养,利用相差显微镜对培养的细胞进行动态观察;并以免疫细胞化学技术对神经元进行染色。结果:在相差显微镜下可见加用N2添加剂和胎牛血清培养的神经元生长良好,胞体形态多样,突起数目多,长度长,与邻近神经元的胞体或突起形成接触,而胶质细胞则大量死亡,神经元纯化率达94%以上,未加用N2添加剂培养的神经元胶质细胞大量存在,神经元纯化率达50%左右。结论:N2添加剂和胎牛血清联合应用可使大鼠皮质神经元得到良好的生长和有效纯化。  相似文献   
82.
It has been previously demonstrated that the generation of measles virus (MV)-specific cytotoxicity (CTL) is reduced in patients with multiple sclerosis (MS). By contrast, CTL specific for influenza virus (FLU) and mumps virus is normal. It is uncertain if reduced CTL is limited to MV in MS patients, or if reduced CTL may be found to other viruses as well. Since MV-specific CTL is predominantly restricted by HLA class II molecules, while FLU-specific and mumps-specific CTL have large HLA class I-restricted components, reduced MV-specific CTL may reflect a broader reduction in HLA class II-restricted CTL in patients with MS. To examine this question we studied the generation of CTL specific for herpes simplex virus type I (HSV). HSV-specific CTL, like MV-specific CTL is predominantly restricted by HLA class II molecules. We found that patients with MS had reduced generation of CTL to both MV and HSV. Most, but not all patients who had reduced generation of CTL to one virus also had a similar impairment with respect to the second virus. Some patients, however, had a reduction in the generation of CTL only to MV or to HSV. These findings extend our earlier observations regarding reduced MV-specific CTL in patients with MS to a second HLA class II-restricted virus, HSV. Such a reduction may reflect discrete impairments in immune function to separate viruses, possibly those that are associated with viral persistence, or may reflect a more generalized defect in HLA class II-restricted CTL.  相似文献   
83.
The polymorphism at the HLA-DPB1 locus has been characterized in a large number of patients with multiple sclerosis (n = 112) and in healthy controls (n = 115). Both patients and controls lived in the southwest of France (in the Pyrénées Atlantiques) and had similar ethnic background. The typing procedure involved the selective amplification of the second exon of the DPB1 locus by polymerase chain reaction, followed by hybridization of the amplified DNA with 14 sequence-specific oligonucleotide probes. Individual alleles were identified by the pattern of hybridization of the different probes. The distribution of the DPB1 alleles was not significantly different in multiple sclerosis patients and controls (p = 0.11). This does not corroborate the reported association of multiple sclerosis with the primed lymphocyte typing (PLT)-defined DPw4 specificity and is not in favour of a role played by polymorphic residues of the DP molecule in susceptibility to multiple sclerosis.  相似文献   
84.
OBJECTIVE: To investigate the relationship of plasma homocysteine (Hcy) level to stroke and genetic factor to elevated plasma Hcy level. METHODS: The plasma Hcy level was measured by capillary electrophoresis-ultraviolet detection and the gene polymorphism of N5,N10-methylenetetrahydrofolate reductase (MTHFR) was studied with PCR-RFLP assay in 43 patients with cortical cerebral infarction and 42 healthy control. RESULTS: The plasma Hcy level of the patients (19.3 +/- 6.0 micromol/L) was markedly higher than that of the controls (13.7 +/- 5.4 micromol/L) (t = 4.16, P < 0.001). There are 3 genotypes, C/C, C/T and T/T, about base-variation of MTHFR gene at locus 677. The plasma Hcy level of the subjects with T/T genotype was higher than that of subjects with other genotypes. However, the frequencies of each genotype and allele were not significantly different between the patients and the controls. CONCLUSIONS: The elevated plasma Hcy level is a risk factor for atherothrombotic cerebral infarction, and is related to the C-->T mutation at locus 677 of MTHFR gene.  相似文献   
85.
We developed a semiautomatic method termed “cortical circumferential profiling” for objective analysis of cerebral cortex function in emission tomographic neuroimaging studies. This method treats cortex as a continuous ring near the outer brain edge. A computer algorithm samples the cortex at 60 contiguous, equiangular locations, using 1-cm2 samples. These values are plotted as a function of cortical angle to produce the cortical circumferential profile. This method was used in a study of regional cerebral perfusion in 15 patients with Alzheimer's disease and 8 elderly control subjects using N-isopropyl [I-123]-iodoamphetamine. Cortical circumferential profiling decreases variability, examines the entire cortex within slices at preselected levels above the orbital-meatal line, and facilitates intrasubject and intersubject comparisons.  相似文献   
86.
The principal-component approach is applied to the analysis of sequences of neuronal action potentials (spike trains). Multiple spike trains are represented as a sequence of vectors of mutual interspike intervals and are considered to be part of the trajectory of a dynamic system. The trajectory matrix is decomposed into a number of ‘basic spike patterns’ and their relative magnitudes by singular-value decomposition. The representation provides a convenient framework for analysis of dynamic relations and cooperation between neurons in an observed network. Examples of applications to simulated and cerebellar data are presented.  相似文献   
87.
Reestablishing myocardial perfusion during evolving myocardial infarction may limit the ultimate extent of infarction if viable myocardial tissue is present when recanalization of the occluded vessel is achieved. This will result in improved left ventricular function and decreased mortality. In addition to their therapeutic benefits, recanalization procedures have contributed greatly to our knowledge of acute myocardial infarction. It has been demonstrated that myocardial infarction most often occurs after thrombotic occlusion of a coronary artery. This has settled a controversy that has preoccupied cardiologists for decades. Selective intracoronary administration of fibrinolytic agents is followed by recanalization in approximately 80% of cases. Therapeutic failures are attributable to occlusion caused by other factors, to inactivation of streptokinase by high antibody concentrations, and to insufficient concentrations of streptokinase at the thrombus as a results of unfavorable flow conditions. This study is dedicated to Prof. Dr. Med. Horst Schmutzler on the occasion of his 60th birthday.  相似文献   
88.
醒脑静注射液对脑缺血再灌注小鼠记忆功能的保护作用   总被引:5,自引:0,他引:5  
目的:观察醒脑静(XNJI)对脑缺血再灌注后小鼠记忆功能的保护作用。方法:采用暂时性阻断两侧颈总动脉的方法制备小鼠脑缺血再灌注损伤的模型。测试其被动回避能力,脑内抗氧化酶活性及小鼠断头喘气时间,结果:XNJI可延长脑缺血再灌注小鼠的避暗潜伏期,减少错误次数,并提高谷胱甘肽过氧化物酶(GSH-Px)的活性。延长小鼠断头喘气时间。结论:XNJI可明显减轻脑缺血再灌注导致的小鼠学习记忆功能障碍状态。其主要机制可能与抗氧化作用有关。  相似文献   
89.
住院脑血管病人主要照顾者负荷   总被引:1,自引:0,他引:1  
目的 探讨影响住院脑血管病人主要照顾负荷的相关因素。方法采用问卷方式对1997年~2000年60名符合研究对象进行调查。结果脑血管病人的主要照顾中60%为配偶,且年龄较大,知识水平偏低,使其身体、心理、社交方面的负荷增大。同时发现雇用身体及心理压力明显低于家属,但两社交负荷无差异。结论临床护理人员应给予住院病人主要照顾一定的协助及指导,减轻家属的压力,使主要照顾能有效地承担起照顾责任。  相似文献   
90.
目的:比较普拉固和鱼油对高胆固醇血症患者的血脂、血粘度、血管内皮功能和心脑血管事件的影响。方法:对266例原发性高胆固醇血症患者经2周洗脱期后,随机分为两组,普拉固组,初服10mg,每晚一次,8周后若TC仍>5.2mmol/L,LDL—ch>3.12mmol/L,则加量至20mg/d,每8周再查血脂,以达到TC<5.2mmol/L,LDL—ch<3.12mmol/L的量作治疗量继续服用。鱼油组,服美国深海鱼油一日三次,一次3g,均于服药8周复查血脂、血粘度及血管内皮功能等并作16月随访。结果:治疗8周,TC,普拉固组下降26%,鱼油组下降12%(P<0.01)。LDL—ch,普拉固组下降31%,鱼油组下降11%(P<0.01),肱动脉流量介导的舒张与硝酸甘油介导的舒张,普拉固组分别增加104%和19%,鱼油组无明显改变。全血低切粘度,普拉固组减少23%,鱼油组减少10%(P<0.01)。平均随访16月,普拉固组中脑出血1例(0.8%),鱼油组发生心脑血管事件7例(5.3%),死亡1例(P<0.05)。两组均无明显的不良反应。结论:普拉固是一个安全有效的降脂药,能改善血管内皮功能,降低血粘度,减少高胆固醇血症病人心脑血管事件发生。  相似文献   
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