Cortical activation during retrieval of arithmetical facts and actual calculation: a functional magnetic resonance imaging study

By using functional magnetic resonance imaging (fMRI), the neural substrates involved in mental recitation of the single-digit multiplication table and serial subtraction were studied. The former depends mostly on well-learned arithmetical facts, while the latter requires arithmetic processing. Activation during each task was compared with that in a number counting control. During the recitation of single-digit multiplication, the activated regions included the area lying along the left intraparietal sulcus, the premotor and supplementary motor areas, and the posterior portion of the left inferior frontal gyrus. The areas activated during serial subtraction included these areas as well as the bilateral prefrontal and right parietal areas. From the results obtained during retrieval of the multiplication table in this study and previous studies, it was concluded that semantic memory of the multiplication table is stored in the area lying along the intraparietal sulcus and that the frontal areas play an executive role in utilizing the semantic memory of arithmetical facts. It was assumed that the arithmetical facts requiring actual calculation are also stored in the same region. The additional activation during serial subtraction compared with the activation during retrieval of the multiplication table is probably due to the processes of actual calculation. These processes include proper alignment of digits, which may have caused the right parietal activation, and maintaining digits needed for the mental serial subtractions, which may have caused the bilateral prefrontal activation.     

基于增量费用比的医用耗材分类的循证评价探索

目的探索基于增量费用比的医用耗材分类的循证评价方法并进行实证检验。方法借鉴四象限图进行耗材证据分类探索。结果医用耗材管理科推荐的项目中95.22%获得小组推荐,小组推荐的项目100%通过委员会决议。医用耗材管理科意见、小组意见与委员会决议的相关性较高。结论 "一维度"模型更利于小组意见生成与委员会决策。以诊疗技术所需耗材整体费用为基础,更接近实际情况。分类临界值有待进一步优化,分类依据需根据医院情况不断调整。基于增量费用比的医用耗材循证证据分类评价方法是一种适合中国国情的、简单快速的医院卫生技术评估方法。     

四种卡介苗重组疫苗对小鼠免疫原性的研究

目的研究esat6-卡介苗重组疫苗、mpt64-卡介苗重组疫苗、ag85a-卡介苗重组疫苗、ag85b-卡介苗重组疫苗的免疫原性。方法通过ELISA法检测小鼠血清中特异性抗体,用MTS法分析其脾淋巴细胞增殖指数。结果以生理盐水、卡介苗为对照,用各卡介苗重组疫苗免疫小鼠后,各组小鼠体重变化与对照组相比差异无统计学意义。应用不同抗原检测各组小鼠不同时间采集的血清,各组有其特异性抗体产生;ag85a-卡介苗重组疫苗能提高卡介苗刺激B细胞产生抗体的水平;各卡介苗重组疫苗免疫后15d,抗体水平已有升高,45d时达到最高水平。用不同抗原刺激各组小鼠脾淋巴细胞,平均刺激指数均达2.0以上,esat6-卡介苗重组疫苗组小鼠脾淋巴细胞的刺激指数稍高,其它各组之间差异无统计学意义。结论结核分枝杆菌esat6、mpt64、ag85a、ag85b基因在卡介苗中都能够表达特异的蛋白,刺激小鼠产生特异性抗体,均能刺激T淋巴细胞产生细胞免疫。     

半夏的快速繁殖与胚状体诱导

采用单因素比较、均匀设计、正交设计等方法，考察了半夏愈伤组织和胚状体诱导以及植株再生的几个主要影响因素，结果表明外植体来源、激素种类和水平、基本培养基类别均对半夏愈伤组织的诱导有直接影响；影响胚状体诱导的主要因素为活性碳，此外，培养基种类、天然附加物对胚状体诱导也有一定影响；较低浓度的6-BA和NAA对半夏胚状体再生植株有利。     

Genotoxic assessment of oxcarbazepine and carbamazepine in drosophila wing spot test

In this study, different concentrations of two antiepileptic drugs, carbamazepine (CBZ) and oxcarbazepine (OXC), have been evaluated for genotoxicity in the wing spot test of Drosophila melanogaster. The wing spot test detects different kinds of somatic mutations and allows detection of mitotic recombinations. Third-instar larvae trans-heterozygous for two genetic markers mwh and flr, were treated at different concentrations of the drugs. Oxcarbazepine exposure concentrations were 1.88, 3.75, 7.50 and 15mug/ml. Carbamazepine exposure concentrations were 5, 10, 20 and 40mug/ml. In addition, the observed mutations were classified according to size and type of mutation per wing. CBZ was genotoxic in terms of total mutations per wing in the highest two doses; the same was true for OXC in the highest three doses. Survival rates of flies used in the experiments were significantly lower than that of the control group showing both drugs to have toxic effects to Drosophila melanogaster larvae. Clone formation frequency for 10(5) cells was lower in OXC than CBZ. However this was lower than the critical genotoxicity frequency of 2.0.     

球形红细胞计数在遗传性球形红细胞增多症诊断中的意义

目的：探讨球形红细胞计数在诊断遗传性球红细胞增多症中的意义。方法：总结１５例遗传性形红细胞增多症患儿，比较其球形红细胞计数，红细胞脆性试验、酸化甘油试验的意义。结果：球形红细胞计数小于１０％１０例（１０／１５），１０％－２０％４例（４／１５），但其红细胞危性试验及酸化甘油试验均为阳性。结论：对于周血球形红细胞计数小于１０％的非典型病例，红细胞脆性试验及酸化甘油试验对于遗传性球红细胞增多症的诊断具有     

一氧化氮对成纤维细胞增殖及胶原合成的影响

在参与肝纤维化形成的细胞中，成纤维细胞能大量合成和分泌胶原蛋白。其质和量决定了组织器官的纤维化过程。我们研究发现，一氧化氮(nitric oxide，NO)具有抗肝纤维化作用。本文在此基础上，观察NO对体外培养的成纤维细胞增殖及胶原合成的影响，进一步阐明NO的抗肝纤维化作用。     

不同时期、不同处理方法的连翘压条繁殖研究

目的：确定连翘最佳的压条时间和方法,完成连翘野生抚育的关键技术。方法：采用对照、环剥、纵刻、高锰酸钾和激素处理。生长期内每隔30 d选择母株样本处理,并做50株重复。结果：环剥和纵刻处理的生根速率、数量和质量最优;压条时间以6月中下旬为宜。结论：压条繁殖的成活率与株龄、枝龄、生长部位、发育状况、土壤、温度、水分等多方面的因素有关。     

中药双黄补对体外培养人牙周膜细胞增殖活性的影响

背景：目前的研究大多为单味中药或单一中药成分对体外培养人牙周膜细胞的影响,而中药组方提取液对体外培养细胞影响的研究较少。 目的：观察中药双黄补对体外培养的人牙周膜细胞增殖活性的影响。 设计、时间及地点：对比观察实验,于2008-11/2009-02 在河北医科大学第四医院科研中心完成。 材料：人牙周膜细胞组织选自河北医科大学第四医院口腔科要求手术拔除的埋伏多生牙者。黄连、黄芩、骨碎补均购自河北医科大学第四医院中药房。 方法：采用组织块法体外培养人牙周膜细胞。水提醇沉法制备双黄补提取液。以每 1 mL药液含生药 1 g加入体积分数20%的胎牛血清培养液,稀释成质量浓度为10,25,50,100,150,200,250,500,750,1 000 mg/L,分别作用于体外培养的人牙周膜细胞,以不加双黄补提取液的培养细胞为对照。 主要观察指标：采用四甲基偶氮唑蓝法测定培养细胞增殖活性的变化,应用流式细胞术检测100 mg/L的双黄补提取液对牙周膜细胞周期的变化和对成纤维细胞生长因子18水平的影响。 结果：双黄补对人牙周膜细胞的增殖活性的影响存在质量浓度和时间效应,各质量浓度双黄补均能促进体外培养人牙周膜细胞的增殖活性,其中以100 mg/L质量浓度促增殖活性作用最明显(P < 0.01),相同质量浓度不同作用时间对细胞促增殖活性作用也不同,以48 h作用最明显(P < 0.05)。与对照组相比,100 mg/L的双黄补促进牙周膜细胞成纤维细胞生长因子18水平增高,S期和G2M期细胞数目增多,在48 h最明显。 结论：中药双黄补可增强人牙周膜细胞的增殖活性,具有明显的浓度效应和时间效应。