毛细管电泳-激光诱导荧光法分离四种神经递质类氨基酸的条件优化

目的探讨毛细管电泳分离神经递质类氨基酸的影响因素。方法采用毛细管电泳法分离4种神经递质类氨基酸的荧光素异硫氰酸酯(FITC-AAs)衍生物,分析电泳缓冲液、表面活性剂以及衍生条件对分离的影响。结果电泳缓冲液的组成、浓度、pH值、表面活性剂以及衍生条件对4种FITC-AA衍生物分离有很大影响,在以75 mm ol/L,pH 9.42硼酸盐含100 mm ol/LSDS为电泳缓冲液,50 mmol/LpH 9.8硼酸盐为衍生缓冲液,4种FITC-AA衍生物20 min内得到很好分离。结论通过条件优化,毛细管电泳-激光诱导荧光技术分离神经递质类氨基酸的分离效果能得到很大提高。     

血糖监测仪性能评价及相关影响因素探讨

目的探讨血糖监测仪的性能及影响其测定的有关因素。方法使用强生稳步倍加型血糖监测仪及血糖仪配套试纸所测毛细血管全血糖（CBG）结果，与同时收集并在美国强生Vitros250全自动干式生化分析仪上用葡萄糖氧化酶法所测的静脉血浆糖（VPG）结果比较，并且对血糖仪的总重复性、同一血标本不同体积、贫血标本、不同抗凝剂标本等进行了摸索，探讨对血糖仪测定的影响。结果（1）CBG与VPG结果差异无统计学意义（P〉0．05）；（2）血糖仪的精度较好，总重复性变异系数（CV）为1．6％；（3）标本体积在10～50μL，测定值之间差异无统计学意义；（4）氟化钠对血糖仪测定有负干扰，结果偏低；（5）使用者的熟练程度对结果无明显影响，熟练者与非熟练者测定值之间差异无统计学意义（P〉0．05）。结论血糖仪测定CBG简便、快速、适用于糖尿病患者床旁监测或家庭使用，并可用于糖尿病的筛选普查、急诊诊断。     

A fluorometric method for determination of C3b inactivator

A simple method for the determination of C3b inactivator in human plasma was investigated. Fluorescent-labeled C3, which was prepared by treatment with methylamine and a fluorescent thiol reagent, N-(dimethylamino-4-methylcoumarinyl)-maleimide, was used as the substrate. Diluted human plasma is incubated with fluorescent C3, reduced with 2-mercaptoethanol, and subjected to sodium dodecyl sulfate polyacrylamide gel electrophoresis. The fluorescent cleavage product is then determined by scanning the gels with a fluorospectrophotometer. This method is simple and sensitive enough to determine C3b inactivator activity in 1 μl of human plasma.     

微流控芯片电泳测定血清小而密低密度脂蛋白及临床应用价值

目的建立微流控芯片电泳分离血清小而密低密度脂蛋白(sdLDL)的方法并探讨其临床应用价值。方法利用自制的微流控芯片,选择Tricine缓冲液为电泳缓冲液,SDS作为添加剂,电泳分离经硝基苯并噁二唑-C6-酰基鞘胺醇(NBD C6-ceram-ide)预染的脂蛋白,激光诱导荧光技术检测。结果大而轻低密度脂蛋白(lLDL)、sdLDL、极低密度脂蛋白(VLDL)和高密度脂蛋白(HDL)在3 min内得到有效分离。冠心病(CHD)组,sdLDL检出率显著高于正常对照组(P<0.01)。CHD患者血清经连续3次分析,sdLDL出峰时间和峰面积相对标准差分别为2.18%和2.94%。sdLDL阳性组TG水平增高,HDL-C水平降低,均与阴性组存在显著差异(P<0.01和P<0.05)。CHD患者sdLDL与三酰甘油(TG)、载脂蛋白B(apoB)呈正相关(r=0.82和0.79,P<0.0001)。结论微流控芯片电泳可望成为sdLDL的常规分析手段,用于CHD危险性的评估。     

毛细管电泳技术与分子信标技术结合检测基因

目的：研究毛细管电泳技术和分子信标技术结合进行基因检测，建立一种简便、敏感、特异和快速自动化的基因检测的新方法学。方法：提取胃癌患者的癌组织及癌旁组织DNA，PCR扩增p16基因外显于2，进行琼脂糖电泳检测，SSCP分析，PCR扩增产物与自行设计探针杂交后毛细管电泳检测。结果：有p16外湿子2 PCR扩增产物的癌组织与分子信标探针液相杂交后毛细管电泳仪检测可见检测峰。结论：毛细管电泳技术和分子信标技术结合检测基因产物是在临床及基础研究中可作为一种基因产物检测的实用手段。     

Quantification of arterial cerebral blood volume using multiphase-balanced SSFP-based ASL

A new technique is introduced in this study for in vivo measurement of arterial cerebral blood volume by combining arterial spin labeling with a segmented multiphase balanced steady-state free precession (bSSFP) readout sequence. This technique takes advantage of the phenomenon that the longitudinal magnetization of flowing blood is not or only marginally disturbed (besides T(1) relaxation) by the bSSFP ± α pulse train. When the blood water exchanges into tissue, it becomes quickly saturated by the bSSFP pulse train due to 0 velocity and reduced T(1), T(2) relaxation times. Therefore, labeled blood water behaves like an intravascular contrast agent in multiphase bSSFP scans, and can be used to quantify arterial cerebral blood volume in a similar way as dynamic susceptibility contrast MRI. Both Bloch equation simulation and in vivo experiments were carried out to demonstrate the feasibility for quantifying cerebral blood volume in arteries, arterioles, and capillaries using two variants of the proposed method. Functional MRI of visual cortex stimulation was further performed using multiphase bSSFP-based arterial spin labeling and compared with vascular-space occupancy contrast. The proposed multiphase bSSFP-based arterial spin labeling technique may allow separation of cerebral blood volume of different vascular compartments for functional MRI studies and clinical evaluation of the cerebral vasculature.     

双重PCR检测急性髓系白血病FLT3-ITD和NPM1基因突变

本研究旨在建立一种同时筛查FLT3-ITD突变和NPM1突变的检测方法.设计2对引物,分别扩增NPM1基因的外显子12和FLT33基因的外显子14、内含子14、外显子15,以覆盖几乎所有已知突变位点.对双重PCR体系的反应程序和引物浓度比例进行优化,将双重PCR产物通过毛细管电泳分离,根据野生型产物和突变型产物的大小差...     

Changes in atrial natriuretic factor during preload reduction with nitroglycerin in patients with congestive heart failure

Summary. Nine patients with congestive heart failure, New York Heart Association class II-III, were evaluated with right heart catheterization. Plasma atrial natriuretic factor (ANF) was determined in blood samples from the pulmonary artery simultaneously with recordings of right atrial, pulmonary arterial, pulmonary capillary wedge and systemic arterial pressures and heart rate during preload reduction with 0·5 mg nitroglycerin sublingually. Basal plasma ANF levels were higher in patients with congestive heart failure compared to normal controls, and correlated to right atrial, pulmonary arterial, and pulmonary capillary wedge pressures. After nitroglycerin all patients had reductions in right atrial, pulmonary arterial, and pulmonary capillary wedge pressures and a simultaneous decrease in plasma ANF concentrations, reaching lowest values after 10 min. Central pressures and plasma ANF rose to baseline values within 30 min. After nitroglycerin plasma ANF concentrations correlated to pulmonary arterial and pulmonary capillary wedge pressures, while changes in plasma ANF correlated to changes in right atrial and pulmonary arterial pressures. These results provide further evidence that ANF is released by a pressure-sensitive mechanism and demonstrates that ANF secretion in relation to central pressure variations is preserved in patients with congestive heart failure and that the response is rapid.     

Faucets as a reservoir of endemic<Emphasis Type="Italic"> Pseudomonas aeruginosa</Emphasis> colonization/infections in intensive care units

Objective To evaluate the role of faucets as a reservoir for Pseudomonas aeruginosa colonization/infection of patients hospitalized in intensive care units (ICUs).Design Prospective epidemiological investigation performed during a nonepidemic period of 1 year. The inner part of the ICU faucets were swabbed for P. aeruginosa. Data were recorded on all patients with at least one culture of a clinical specimens positive for P. aeruginosa. Pulsed-field gel electrophoresis was used to characterize the strains.Setting Five ICUs of a university hospital which are supplied by two separate water distribution networks.Patients During a 1-year period 132 cases were investigated.Results In 42% of cases (56/132) there were isolates identical to those found in the faucets, with a total of nine different genotypes. Among the nine genotypes isolated from both patients and faucets one of them, the most prevalent, was isolated in the two networks and in 30 cases. The other eight genotypes were recovered almost exclusively from either one (three genotypes in 12 cases) or the other (five genotypes in 12 cases) network and from the patients in the corresponding ICUs.Conclusions These results suggest that the water system of the ICUs was the primary reservoir of patients colonization/infection with P. aeruginosa in a substantial proportion of patients, although the exact mode of acquisition could not be determined.     

Conversion of Type III Hyperlipoproteinaemia to Type IV Hyperlipoproteinaemia by a Fat-Free, Carbohydrate Rich Diet

Abstract. Hyperlipoproteinaemia type III has been considered a clear cut clinical entity characterized by the presence of cholesterol rich "floating" beta very low density lipoproteins (VLDL) after ultracentri-fugation. Carbohydrate inducibility is pronounced in type III. This study was undertaken to elucidate the effect of a high carbohydrate diet in type III as an effort to clarify a suggested association between type III and IV hyperlipoproteinaemia. On an isocaloric fat free carbohydrate rich diet the lipoprotein pattern changed as the VLDL triglycerides increased 31 per cent on average and LDL and HDL cholesterol decreased by 40 and 22 per cent. The high ratio cholesterol/triglycerides in VLDL was normalized. The lipoprotein levels in serum after carbohydrate induction showed all characteristics of a type IV with high VLDL triglycerides, normal cholesterol/triglyceride ratio in VLDL, subnormal cholesterol levels in LDL and HDL with changed relation between LDL₁ and LDL₂. On electrophoresis the floating beta band disappeared. It is probable that depending on the nutritional situation, the metabolic defect in type III may be expressed either as a type III or a type IV. An explanation of the effects of the carbohydrate rich diet on the lipoprotein pattern is suggested.