快速心房起搏对家兔L-型钙通道和Kv4.3钾通道基因表达的影响

目的观察快速心房起搏对家兔心房L型钙通道亚单位和Kv4.3钾通道基因表达的影响。方法新西兰大耳白家兔36只,随机分成6组,经右颈外静脉穿刺置入电极于右房,分别给予0、3、6、12、24或48h快速心房起搏,停止起搏后取右房组织,应用半定量反转录聚合酶链式反应测定各时相点L型钙通道α1c,β1,α2亚单位,钾通道Kv4.3mRNA的表达水平。结果L型钙通道α1c、β1亚单位在快速起搏6h后表达水平下调,并随着起搏时间的延长进一步下调。α2亚单位的mRNA表达在各时相点无显著差异。Kv4.3的mRNA的表达在快速起搏的24h和48h下降分别达55.50%（P<0.01）和59.12%（P<0.01）。48h后下降达到一个平台期。结论快速心房起搏可导致L型钙通道亚单位和Kv4.3钾通道mRNA表达下调。     

HIV抗体快速检测试剂的临床评估

目的:通过对HIV抗体快速检测试剂的临床评估,为HIV检测试剂的临床应用提供参考.方法:对快速试剂的使用性能进行比较,并采用美国输血协会(AABB)血清盘、临床样品血清盘、特性血清盘(阳性样品盘)、稀释系列血清盘评估快速试剂的敏感性和特异性.结果:三种快速试剂在检测AABB血清盘时,敏感性分别是86.4%、86.4%、100%,特异性皆为100%;三种快速试剂在检测临床样品血清盘时,敏感性分别是88.6%、91.4%、97.1%,特异性皆为100%.快速试剂具有很高的阳性预期值,对于低危人群(感染率很低人群)也具有很高的阴性预期值.快速试剂检测弱阳性的样品(酶联试剂s/co比值小于6～8的样品)存在漏检.快速试剂与ELISA参考试剂在分析灵敏度方面相差3个以上倍比稀释度.结论:快速试剂具有较好的使用特性,非常适用于样本量较少的实验室及对低危人群的HIV筛查,在对高危人群筛查时,可能有弱阳性样品漏检,同时快速试剂在分析灵敏度方面有待提高.     

基于匹配实测表面肌电信号的模型参数辨识

目的 通过对仿真与真实表面肌电信号(sEMG)的波形匹配以及肌疲劳现象的分析,研究sEMG信号的模型参数辨识问题. 方法 在运动单位仿真的基础上,引入神经激励对运动单位的募集和发放控制特性,建立了一个较为完善的sEMG信号生理学模型.利用调整模型相关生理参数使仿真与真实sEMG信号的运动单位动作电位(MUAP)波形相匹配的方法,实现对模型参数进行估计,通过调节肌纤维传导速度(MFCV)使仿真与真实sEMG信号的平均频率(MNF)及中值频率(MDF)拟合直线趋势相似的方法,研究肌肉的疲劳现象及其机理. 结果 适当调节sEMG信号模型参数可使仿真信号波形逼近真实sEMG信号波形,各个肌纤维的MFCV在模拟恒力持续收缩过程中减小时,仿真信号的MNF和MDF拟合直线呈下降趋势. 结论 采用模型方法能够实现仿真与真实sEMG信号波形的良好匹配,并能够有效地表达肌肉的疲劳过程,可应用于肌电信号相关领域的研究.     

A perspective on measurement of mutations in vivo.

The development of transgenic mouse lines with target genes that are suitable for tissue-specific mutagenesis studies is an important contribution to the field of environmental mutagenesis. These models can accommodate many of the questions relating to metabolism, distribution and relative potency of mutagens as well as providing a more comprehensive system for the identification of mutagens. However, the lesions that the field has learned about methods, development and validation from the use of in vitro systems must be applied to the development and validation of transgenic models.     

大麦芽发酵物化学成分的鉴别分离及其抗缺氧效果研究

目的研究鉴别大麦芽发酵物的成分组成,分离其抗缺氧有效成分,为建立药物有效成分提取分离工艺及减少服药剂量提供科学依据.方法按药典方法测定发酵物的理化指标;发酵物分别用水和乙醇提取分离后,通过纸层析法和试管法,用特异显色剂进行化学成分鉴别;采用溶剂极性梯度、乙醇浓度梯度、酸性溶剂三种方法,分别对大麦芽发酵物搅拌回流提取两次,离心分离,回收溶剂,浓缩,低温干燥作试样;溶剂不溶物低温干燥后也作试样;选雄性健康小白鼠,按体重随机分组,每组20只.腹腔注射0.2ml药液,给药40min后,置125ml广口瓶中以橡皮塞密闭进行抗缺氧实验,观察记录动物死亡时间,同时设原发酵物和蒸馏水空白两个对照组.最后统计实验组与对照组的动物存活时间增加率,并对组间结果进行t检验.结果大麦芽发酵物含蛋白质18.99%,总糖17.50%,总酸度9.01%;纸层析法和试管法定性鉴别试样中蛋白质、糖类、有机酸、酚性物和油脂均呈阳性;不同溶剂提取物的动物密闭抗缺氧效果均非常显著高于水对照组(P＜0.01),但却明显低于原发酵物对照组.而不同溶剂不溶物的抗缺氧效果则显著优于原发酵物(P＜0.05).结论发酵物含蛋白质、肽类、氨基酸、单糖、还原糖、多糖类、有机酸、酚性物和油脂等成分.其抗缺氧有效成分可能是一类弱极性化学物质.     

止咳枇杷冲剂中枇杷叶和桔梗的薄层色谱鉴别研究

研究止咳枇杷冲剂中枇杷叶和桔梗的薄层色谱鉴别方法。分别取枇杷叶和桔梗药材，制剂及阴性制剂的醋酸乙酯提取液，在硅胶板上前者以ψ（氯仿：甲醇：水）=2：2.25:1.5展开，后者以ψ（正已烷：氯仿：甲醇）=5：4：0.3展开，磷钼酸乙醇溶液显色，在两者供试吕色谱中与各自对照药材色谱相应位置上，分别有相同的蓝绿色特征斑点；阴性制剂色谱图中无此斑点，因此该方法可作为这两味中药的鉴别方法。     

Automatic discrimination of myoelectric signals via parallel cascade identification

It has recently been shown that it is possible to discriminate accurately among myoelectric signals underlying different muscle contraction types, specifically elbow flexion and extension and forearm pronation and supination. It was reported that once a number of distinctive features had been extracted from the myoelectric signals, a neural network could be trained to distinguish the contraction types with an impressively high accuracy. In the present paper, we show that a technique known as parallel cascade identification can be used to construct classifiers that can also accurately, differentiate the contraction types. The use of parallel cascades has the benefit of dispensing with the need for feature extraction, so that raw myoelectric signal data can be used directly. In addition, very little data are required to train the parallel cascades to distinguish accurately novel incoming myoelectric signals. Results of using parallel cascades to distinguish foream pronation, supination, and elbow flexion are presented.     

定坤丹的显微鉴定研究

对定坤丹(蜜丸)进行了显微鉴定研究,将29种组成药物全部检出,对各组成药物的显微鉴别特征作了简明描述,并附显微特征图。     

Interpretation of functional series expansions

While much research has been devoted to the implementation and application of Volterra and Wiener functional series expansions in the identification and characterization of biological systems, little effort has been focused on the fundamental problem of interpreting the resulting kernels. This paper describes the application of the series to the components of a known model of the human pupil control system. As more complicated elements are put together, insight into kernel interpretation is built up incrementally until the total system is identified. Practical limitations and methods are also discussed.     

方格星虫多糖分离纯化及性质鉴定

以方格星虫（Sipunculus nudus）体壁和血液为试验材料，经胰蛋白酶水解，Sevage法去除蛋白质，乙醇沉淀得到粗多糖，透析并冷冻干燥后分别得到方格星虫体壁多糖（SWP）和血液多糖（SBP）。经凝胶渗透色谱分析，SWP和SBP均为单一组分，相对分子质量分别为284528和198212。红外光谱分析表明，两种多耱结构相似，不含硫酸基团，均含有葡萄耱、半乳糖、木糖和阿拉伯糖。SBP含有乙酰氨基，而SWP不含乙酰氨基，它们是以α-糖苷键或β-糖苷键连接的呋喃多糖。