杂交技术在法洛四联症中的应用

目的:总结杂交技术镶嵌治疗儿童法洛四联症(TOF)的经验。方法:外科术前介入治疗:3例有巨大体肺侧支(APCAs)的重症TOF在根治术前予以侧支血管堵塞术。外科术后镶嵌治疗:6例TOF根治术后残余分流,其中4例残余膜周部室间隔缺损,1例残余左室右房通道室间隔缺损,1例残余房间隔缺损,分别予以经导管残余心脏缺损封堵术。结果:3例有巨大APCAs的重症TOF在根治术前予以侧支血管堵塞术后随即进行外科手术,皆获得满意效果。6例TOF根治术后残余分流者行经导管封堵术封堵成功,随访无残余分流及心脏瓣膜异常,未出现心律失常。结论:杂交技术镶嵌治疗伴有巨大APCAs及术后存在残余分流的TOF安全、有效。     

On the Structure and Properties of AlMgB14-TiB2 Composites Obtained from SHS Powders by Spark Plasma Sintering

AlMgB₁₄-TiB₂ composite materials were fabricated by self-propagating high-temperature synthesis (SHS) followed by spark plasma sintering of the obtained SHS products. It was found that, during the SHS, the AlMgB₁₄ phase is formed at a donor (Ti + 2B) to acceptor (Al₁₂Mg₁₇-B) mass ratio of 3:7 and 4:6, respectively. The specimen sintered from the SHS powder with the donor:acceptor mass ratio of 5:5 at a temperature of 1470 °C has a uniform skeletal structure. The average hardness of the obtained specimen is 30.1 GPa.     

Research on the Grinding Energy Density in a Jet Mill

Raw materials are used in many industrial technologies. The raw material frequently has to be prepared as an intermediate with an appropriate particle size distribution, which requires the use of grinding. In grinding processes, energy consumption is a very important profitability criterion for the applied particular size reduction technology. The paper describes the comminution process that takes place in the jet mill using a modified form of the thermodynamic theory of grinding. In this theory, new material characteristics have been added: the surface and volumetric density of grinding energy. The thermodynamic theory is a combination of the classical Kick’s theory and the modified form of Rittinger’s theory. The tested physical magnitudes are a measure of the energy consumption of the grinding process. They describe the energy that must be provided in the grinding process to overcome interactions between particles related to the volume and surface of the material. Knowledge of these magnitudes is necessary to model thermomechanical phenomena in the solid state. The paper presents the results of research on comminution in a jet mill, on the basis of which the values of the tested material magnitudes were determined. It is graphically shown how the values of the tested magnitudes depend on the grain size of the ground samples.     

Analysis of N-ras gene mutation and p53 gene expression in human hepatocellular carcinomas

AIM:To study the relationship between N-ras gene mutation and p53 gene expression in the carcinogenesis and the development of human hepatocellular carcinomas (HCC).METHODS:The N-ras gene mutation and the p53 gene expression were analyzed in 29 cases of HCC by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and immunohistochemistry.RESULTS:Thirteen cases of HCCs were p53 positive (44.8%), which showed a rather high Cpercen-tage of p53 gene mutation in Guangxi. The aberrations at N-ras codon 2-37 were found in 79.31% of HCCs and 80.77% of adjacent non-tumorous liver tissues. More than 2 point mutations of N-ras gene were observed in 22 cases (75.86%). Twelve cases (41.37%) of HCCs showed both N-ras gene mutation and p53 gene expression.CONCLUSION:N-ras gene and p53 gene may be involved in the carcinogenesis and the development of HCC.That 38% of HCCs with N-ras gene mutation did not express p53 protein indicates that some other genes or factors may participate in the carcinogenesis and the development of HCC.     

False-positive results in ELISA-based anti FVIII antibody assay may occur with lupus anticoagulant and phospholipid antibodies

Summary. The evaluation of a prolonged aPTT often includes Lupus Anticoagulant, Antiphospholipid Antibodies, and Factor VIII (FVIII) inhibitors. We have noticed that patient samples positive for lupus antibody (LA) are frequently also positive for FVIII IgG antibodies in an enzyme‐linked immunosorbent assay (ELISA), indicating the need for follow‐up testing with a more labour‐intensive functional assay for FVIII inhibition. This study evaluates the potential for a FVIII IgG ELISA to yield false‐positive results in patient samples positive for LA or other antiphospholipid antibodies. A total of 289 residual de‐identified patient samples positive for LA (n = 143), anti‐cardiolipin IgG (n = 84), or beta2‐glycoprotein antibody (n = 62) were tested for FVIII IgG using a commercial ELISA. Samples with positive FVIII IgG ELISA results were further tested for FVIII activity using a clot‐based FVIII inhibitor assay. The FVIII IgG ELISA yielded positive results in 39 (13%) of the samples tested, including 13/143 (13%) LA‐positive, 15/85 (18%) aCL IgG‐positive and 6/62 (10%) β2‐glycoprotein IgG‐positive samples. The clot‐based FVIII inhibitor assay yielded negative results in all 39 FVIII IgG‐positive specimens tested, indicating discrepancy with the FVIII IgG ELISA results. Patient specimens positive for LA, aCL IgG, or β2‐glycoprotein IgG may yield false‐positive results for FVIII antibodies. Caution is warranted in interpreting FVIII antibody results in these cases.     

Prognosis of life expectancy of patients with ischemic heart disease detected during mass screening]

Prospective 5-year follow-up was accomplished among males ranging in age between 50 and 59 and forming four random samples from the respective population of the Bauman region in Moscow subjected to primary cross-sectional epidemiologic survey. The results show that in primary survey general mortality and the mortality of ischemic heart disease were significantly higher among males with ischemic heart disease than among the rest of the individuals examined. The mortality of ischemic heart disease proved to be particularly high among individuals with a history of myocardial infarction (relative death risk 5.8) and among those with typical anginal pectoris (relative death risk 4.4). Ischemic heart disease mortality was lower (relative death risk 2.1) in the group of males who had suffered from silent myocardial infarction or had silent ischemic heart disease than among those who had had myocardial infarction or with angina pectoris, but higher among males who did not have these diseases. To study the prognostic value of atypical chest pain in angina pectoris, it is necessary that prospective follow-up be continued.