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101.
目的:介绍言语流畅性的测量工具,考察言语流畅性与记忆之间的关系,探讨言语流畅性的神经生理基础。资料来源:应用计算机检索Sciencedirect 1975-07/2005-05中与言语流畅性相关的文献,检索词为“verbal fluency”,限定文章语言种类为英文。资料选择:对资料进行初审,选取文章标题中含有“verbal fluency”的英文文献。纳入标准:①对言语流畅性测量任务的研究。②对言语流畅性与记忆的研究。③对言语流畅性神经生理基础的研究。资料提炼:共收集到651篇关于言语流畅性的文章,纳入30篇用于本综述。资料综合:测量言语流畅性的任务主要分为简单任务(包括音位流畅性任务和语义流畅性任务)与复杂任务(包括可能工作、替代使用、草拟、推断、物品制作以及新的使用方法等)。言语流畅性任务的完成主要涉及到记忆搜索的过程,另外,精细组织的语义网络系统对于言语流畅性任务来说也是非常重要的。言语流畅性的神经生理基础包括了总体基础,前额叶,海马以及大脑两半球的不对称性。结论:言语流畅性作为人类语言基本技能的一项指标,对语言认知研究具有极其重要的意义。它不仅是神经心理研究的一项非常重要的检测和诊断指标,也是一种研究人类心理的非常有用的研究工具,是探索人类语言与认知、创造之迷进而探索人类意识之迷的钥匙。  相似文献   
102.
目的:观察碱性成纤维细胞生长因子对大鼠脑出血后出血灶周围脑组织和出血侧海马bax、bcl-2基因表达的影响,探讨神经营养因子对神经细胞调亡的调控。方法:实验于2006-01/10在广西医科大学医学科学实验中心完成。①取成年清洁级Wistar大鼠72只,雌雄各半,体质量250g左右。②采用脑内囊注射胶原酶建立大鼠脑出血模型,动物于苏醒后按Bederson法进行神经病学评分,评分>3分后入选本实验,入选72只大鼠随机抽签法分为3组,每组24只。碱性成纤维细胞生长因子组按8μg/kg剂量肌肉注射,1次/d;生理盐水组肌肉注射等剂量的生理盐水,1次/d;模型组不作任何干预。③每组分别于干预后1,3,7d随机抽取8只大鼠,麻醉状态下取出血灶周围脑组织和出血侧海马,采用半定量反转录-聚合酶链反应检测调亡调控基因bax mRNA,bcl-2mRNA的表达。结果:在建立脑出血模型中共5只大鼠死亡,随后对死亡动物进行解剖,发现脑内血肿量过大,致脑疝形成而导致死亡,后随机补充动物。72只大鼠进入结果分析。①血肿周围脑组织bax mRNA表达:干预后3d,7d,碱性成纤维细胞生长因子组血肿周围脑组织bax mRNA表达比生理盐水组明显减少(3d:0.54±0.19,0.76±0.23,P<0.05;7d:0.45±0.19,0.71±0.16,P<0.01)。②血肿周围脑组织bcl-2mRNA表达:干预后3d,7d,碱性成纤维细胞生长因子组的血肿周围脑组织bcl-2mRNA表达比生理盐水组明显增高(3d:0.68±0.25,0.39±0.19,P<0.05;7d:0.80±0.21,0.48±0.18,P<0.01)。③出血侧海马bax mRNA表达:干预后3d和7d,碱性成纤维细胞生长因子组的出血侧海马bax mRNA表达比生理盐水组均明显减少(3d:0.54±0.18,0.70±0.11;7d:0.43±0.24,0.69±0.18,P均<0.05)。④出血侧海马bcl-2mRNA表达:干预后3d和7d,碱性成纤维细胞生长因子组的出血侧海马bcl-2mRNA表达比生理盐水组均明显增多(3d:0.66±0.11,0.50±0.15;7d:0.72±0.12,0.52±0.22,P均<0.05)。结论:碱性成纤维细胞生长因子能调节凋亡相关基因,提高大鼠脑出血后大脑脑组织和海马bcl-2mRNA的表达,降低bax mRNA的表达。  相似文献   
103.
The mouse monoclonal antibody M2A1 of IgG1 class, which is highly specific for blood group M antigen, was obtained and characterized by means of hemagglutination, enzyme-linked immunosorbent assay, immunoblotting, and inhibition assays. The use of modified M glycoprotein preparations for inhibition tests and of variant McN and Henshaw red cell membranes for immunoblotting showed that M2A1 recognized an epitope including the NH2-terminal serine and sialic acid residues of glycophorin A, whereas the fifth glycine residue was not involved. The reactivity of the antibody with M antigen was distinctly dependent on ionic strength and pH; the optimum was at pH 8 to 9. The alpha-amino group of terminal serine residue was not necessary for the reaction with M2A1 antibody, and the results obtained suggested that the positive charge of this group contributed to decreasing antigen-antibody reactions at pH below 8. The reaction of the antibody with blood group N antigen was not detectable in any of the assays used.  相似文献   
104.
Elevated plasma homocysteine, an independent risk factor for cardiovascular disease (CVD) can be lowered by administration of pharmacological doses of folic acid. The effect of lower doses in apparently normal subjects is currently unknown but is highly relevant to the question of food fortification. Healthy male volunteers (n = 30) participated in a chronic intervention study (26 weeks). Folic acid supplements were administered daily at doses increasing from 100 micrograms (6 weeks), to 200 micrograms (6 weeks), to 400 micrograms (14 weeks). Fasting blood samples collected before, during and 10 weeks post intervention were analysed for plasma homocysteine, serum and red- cell folate levels. Results, expressed as tertiles of baseline plasma homocysteine concentration, showed significant (p < or = 0.001) homocysteine lowering in the top (10.90 +/- 0.83 mumol/l) and middle (9.11 +/- 0.49 mumol/l) tertiles only. In the low tertile, where the mean baseline homocysteine level was 7.07 +/- 0.84 mumol/l, no significant response was observed. Of the three folic acid doses, 200 micrograms appeared to be as effective as 400 micrograms, while 100 micrograms was clearly not optimal. There is thus a minimal level of plasma homocysteine below which folic acid has no further lowering effect, probably because an optimal folate status has been reached. A dose as low as 200 micrograms/day of folic acid is effective in lowering plasma homocysteine concentrations in apparently normal subjects. Any public health programme for lowering homocysteine levels, with the goal of diminishing CVD risk, should not be based on unnecessarily high doses of folic acid.   相似文献   
105.
Cardiac Ca2+ current (ICa) was shown to be regulated by cGMP in a number of different species. Recently, we found that the NO-donor SIN-1 (3-morpholino-sydnonimine) exerts a dual regulation of ICa in frog ventricular myocytes via an accumulation of cGMP. To examine whether NO also regulates Ca2+ channels in human heart, we investigated the effects of SIN-1 on ICa in isolated human atrial myocytes. An extracellular application of SIN-1 produced a profound stimulatory effect on basal ICa at concentrations > 1 pM. Indeed, 10 pM SIN-1 induced a approximately 35% increase in ICa. The stimulatory effect of SIN-1 was maximal at 1 nM (approximately 2-fold increase in ICa) and was comparable with the effect of a saturating concentration (1 microM) of isoprenaline, a beta-adrenergic agonist. Increasing the concentration of SIN-1 to 1-100 microM reduced the stimulatory effect in two thirds of the cells. The stimulatory effect of SIN-1 was not mimicked by SIN-1C, the cleavage product of SIN-1 produced after liberation of NO. This suggests that NO mediates the effects of SIN-1 on ICa. Because, in frog heart, the stimulatory effect of SIN-1 on ICa was found to be due to cGMP-induced inhibition of cGMP-inhibited phosphodiesterase (cGI-PDE), we compared the effects of SIN-1 and milrinone, a cGI-PDE selective inhibitor, on ICa in human. Milrinone (10 microM) induced a strong stimulation of ICa (approximately 150%), demonstrating that cGI-PDE controls the amplitude of basal ICa in this tissue. In the presence of milrinone, SIN-1 (0.1-1 nM) had no stimulatory effect on ICa, suggesting that the effects of SIN-1 and MIL were not additive. We conclude that NO may stimulate ICa in human atrial myocytes via inhibition of the cGI-PDE.  相似文献   
106.
The efficacy of subcutaneous recombinant human erythropoietin (rhEPO) (500 U/kg; administered twice a week during the 3 weeks before surgery) in the recovery of preoperative hemoglobin concentrations within a 3- week period was studied in 40 patients, each of whom donated 2 units (900 mL) of blood for their own use before total hip replacement surgery. Twenty autologous blood donors received rhEPO (EPO group) and 20 were not treated (control group). The initial hemoglobin concentration (14.0 +/− 1.0 g/dL [140 +/− 10 g/L]) was completely recovered before surgery (14.0 +/− 1.6 g/dL [140 +/− 16 g/L]) in the EPO group, while a decrease from 13.8 +/− 1.1 to 12.2 +/− 1.3 g per dL (138 +/− 11 to 122 +/− 13 g/L) was observed in the control group. The preoperative reticulocyte count showed more than sixfold increase in the EPO group, whereas a twofold to threefold increase was found in the control group. Serum ferritin concentration fell to 42 +/− 29 micrograms per L in the EPO group and to 54 +/− 35 micrograms per L in the control group. The postoperative serum erythropoietin concentration in the EPO group was significantly lower than that in the control group, but it did not differ from the pretreatment value and was attended by a higher hemoglobin concentration after surgery. Only transient flu-like symptoms were mentioned by patients who were treated with rhEPO. Changes in blood pressure or platelet count or other adverse events were not observed.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
107.
目的:观察贞芪扶正颗粒和复方阿胶浆对苯油溶液致小鼠再生障碍性贫血模型的疗效。方法:实验于2005-06/09在河南中医学院药理实验室完成。①选用昆明种成年雄性小鼠90只。按随机数字表法将小鼠分为9组,每组10只:大、中、小剂量贞芪扶正颗粒组:按15,10,5g/kg剂量灌服贞芪扶正颗粒混悬液(主要成分:黄芪、女贞子;甘肃扶正药业科技股份有限公司生产;批号040803,15g/袋)。大、中、小剂量复方阿胶浆组:分别按10,20,30mL/kg剂量灌胃复方阿胶浆(主要成分:阿胶、熟地黄、党参、山楂、人参、蔗糖;山东东阿阿胶股份有限公司生产,批号050446,250mL/瓶),司坦唑醇组:按4mg/kg剂量灌胃司坦唑醇混悬液(司坦唑醇片,广西南宁百会药业集团有限公司生产,批号050306,30mg/片)。空白组和模型组:灌胃同体积的生理盐水(20mL/kg)。每天给药1次,连续给药14d。除空白组外,其余组小鼠皮下注射体积分数0.25苯的玉米油溶液4mL/kg复制苯油溶液致小鼠再生障碍性贫血模型,空白组皮下注射同体积玉米油。②各组小鼠分别于末次给药后24h,进行血常规检测。取右侧股骨,冲出骨髓细胞,采用BI-2000医学图像分析仪计数骨髓有核细胞数。③计量资料符合正态分布、方差齐者用t检验;方差不齐者用t’检验。结果:小鼠90只均进入结果分析。①血细胞测定结果比较:模型组小鼠血红细胞、白细胞、血小板计数和血红蛋白水平明显低于空白组(t=3.39~11.89,P<0.01)。司坦唑醇组3项血细胞计数和血红蛋白水平明显高于模型组(t=4.94~6.73,P<0.01)。大、中剂量贞芪扶正颗粒组和各剂量复方阿胶浆组血白细胞计数明显高于模型组(t=2.32~3.03,P<0.05 ̄0.01)。中剂量贞芪扶正颗粒组和各剂量复方阿胶浆组小鼠血红细胞计数明显高于模型组(t=2.15~4.84,P<0.05 ̄0.01)。大、中剂量贞芪扶正颗粒组和各剂量复方阿胶浆组血红蛋白水平明显高于模型组(t=2.33~4.45,P<0.05 ̄0.01)。大、中剂量贞芪扶正颗粒组和各剂量复方阿胶浆组血小板计数明显高于模型组(t=4.06~6.24,P<0.01)。②骨髓有核细胞数:模型组明显低于空白组(t=8.99,P<0.01)。司坦唑醇组、中剂量贞芪扶正颗粒组和小剂量复方阿胶浆组明显高于模型组(t=2.39~2.82,P<0.05)。结论:贞芪扶正颗粒、复方阿胶浆对皮下注射苯所致小鼠再生障碍性贫血模型血细胞状况及骨髓象均有较好的改善作用,以贞芪扶正颗粒有较为明显的剂量依赖关系。  相似文献   
108.
The effectiveness of the confidential unit exclusion (CUE) procedure recommended by the Food and Drug Administration has been questioned by the blood banking community. The purpose of this study was to determine whether donors were informing the blood center correctly regarding the disposition (transfuse or do not transfuse) of their donated blood. A letter explaining the confidential study and requesting permission to send the participant a questionnaire noting his or her self-exclusion choice was mailed to 230 donors who had chosen transfuse and 276 donors who had chosen do not transfuse. After consent was obtained, participants were sent a second packet and asked to indicate whether they had chosen correctly and, if not, to identify reasons for that incorrect choice. A seven-word terminology quiz made up of words from the CUE form was also enclosed. All participants who had chosen transfuse indicated that this was the correct choice. Approximately 50 percent of those who had chosen do not transfuse indicated that this was an incorrect choice; the most common reason was that "I was not paying attention." The most frequently misunderstood term was "confidential." Donors who chose do not transfuse had a significantly higher rate of error on the terminology quiz (p less than 0.01) than did those who chose transfuse.  相似文献   
109.
Efficient and homogeneous gene transfer to cardiac myocytes is a major target in myocardial gene therapy. The aim of this study was to determine the conditions permitting efficient, homogeneous, adenovirus-mediated gene transfer to cardiac myocytes, with a view to application during coronary artery catheterization. Gene transfer to adult rat ventricular myocytes was conducted using type 5 adenoviruses carrying the lacZ reporter gene. Adenovirus delivery via coronary arteries was performed on isolated perfused rat hearts, and gene transfer efficiency was analyzed on whole ventricles, freshly isolated myocytes, and cultured myocytes. Single-pass delivery of 1 X 10(9) PFU associated with 1 min of no-flow yielded only 1 +/- 0.5% of positive myocytes. Pretreatment by histamine perfusion (10(-5) M final concentration) increased this value to 30 +/- 9% (p < 0.001), and pretreatment by Ca2+-free buffer perfusion increased it to 67 +/- 8% (p < 0.001). Combination of the two pretreatments had no additional effect. Increasing the viral dose to 3 X 10(9) PFU increased transfection efficiency only in permeabilized vessels. The 1-min no-flow period after adenovirus delivery was crucial for efficient gene transfer: despite histamine pretreatment, only 2 +/- 1% positive myocytes were observed without flow interruption (p < 0.05 versus 1 min of no-flow). Gene transfer was shown to occur in situ during cardiac perfusion, rather than during heart digestion or myocyte isolation. This study shows that highly efficient adenovirus-mediated gene transfer to cardiac myocytes in situ can be achieved by single-pass intracoronary vector delivery, provided that vascular permeability is first increased and coronary flow is briefly interrupted.  相似文献   
110.
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