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81.
心室的后负荷、泵功能及与动脉的耦合 总被引:4,自引:0,他引:4
近20年来心室后负荷、泵功能及心室-动脉耦合的研究已有了很大的发展和某些医疗应用.在静态情况下,这一问题的研究已比较成熟.对于动态情形,目前已作了不少动物实验,并提出一些理论模型.本文首先评述20多年来这一问题的发展概况,然后报告笔者近期的研究结果,最后提出进一步需要研究的问题 相似文献
82.
采用微观组织结构分析及宏观复合材料分析结合的方法,分析了猪主动脉瓣的非线性复合材料性质,提出了一种适用于猪主动脉瓣的非线性复合材料本构模型,用提出的非线性复合材料本构模型,对闭合承载状态下的等厚度与变厚度几何模型的猪主动脉瓣的应力分布及变形进行了有限元数值模拟,发现:与各向同性瓣叶相比,单向增强复合材料的瓣叶不但具有较强的承载能力,而且具有较大的柔软性。 相似文献
83.
采用火焰原子吸收分光光度法测定了冠心病患者及健康人血清中Ca、Mg的含量,并比较了Ca/Mg比值。结果显示,冠心病患者血清镁含量明显低于健康人(P〈0.05),Ca/Mg比值有显著差异(P〈0.05)。 相似文献
84.
心宝丸中11种微量、宏量元素的测定分析 总被引:1,自引:1,他引:0
采用火焰原子吸收分光光度法测定了心宝丸中钠,钾,钙,镁,铁,铬,锰,镍,镉,铜,锌11种微,宏量元素的含量。结果表明,心宝丸中含有丰富的微量,宏量元素。为探讨中成药中微量,宏量元素与治疗冠心病的关系提供了有用的数据。 相似文献
85.
以微量元素为指标考察活心喷雾剂两种不同制备工艺 总被引:2,自引:0,他引:2
以微量元素Cu及Cu/Zn比值为指标,考察了活心喷雾剂两种不同制备工艺。结果表明:醇提工艺中Cu及Cu/Zn比值均明显高于水煎液,与以有效成分丹参酮ⅡA为指标考察工艺得出相同的结论。 相似文献
86.
We previously reported that transgenic (TG) mice over-expressing translationally controlled tumor protein (TCTP) developed systemic arterial hypertension at about 6 weeks after birth. In the present study, we identified, using proteomics technologies, 24 other proteins that were differentially expressed in the heart of TCTP over-expressing TG mice. These 24 proteins are involved in a variety of biological processes such as reactive oxygen species metabolism, cytoskeleton organization, fatty acid metabolism, amino acid metabolism and energy metabolism. We determined protein expression levels of the peroxiredoxin (Prx)2, Prx3, myosin light chain 1, stress protein (heat shock protein) 25K, and T-complex protein 1 alpha subunit by western blot analysis. Over-expression of TCTP probably regulates the expression of other proteins which play a pivotal role in a variety of cellular functions in TCTP over-expressing TG mice. 相似文献
87.
Summary The biochemical functions of uridine-diphosphate-amino-sugar conjugates are largely unknown. As a first step to investigate
their biological roles in glycolysis of higher organisms, bovine heart muscle, which metabolizes large quantities of glycogen,
was assayed for uridine-diphosphate-hexosamine. A low molecular mass ultrafiltrate was prepared from the methanolsoluble fraction
of a beef heart homogenate, and the fraction was further purified using anion-exchange and reverse-phase HPLC. Samples were
analyzed by two HPLC methods; anion-exchange in borate buffer and reverse-phase ion-pair chromatography. One newly established
technique employing phenylthiocarbamoyl labelled uridine-diphosphate-hexosamine also was used selectively to separate uridine-diphosphate-hexosamine
from other uridine-diphosphate-sugars. Hydrolysate of purified sample was classified further according to molecular structure.
As a result, phenylthiocarbamoyl labelled HPLC is suitable and easy for the detection of uridine-diphosphate-hexosamine and
its derivatives. 相似文献
88.
89.
In preparation for PET imaging of ischemic myocardial regions, the uptake of 218F-fluoro-2-deoxy-D-glucose (FDG) in the isolated perfused rat heart was studied under normoxic and hypoxic conditions. With this model we were able to demonstrate an about 2.5 fold higher uptake of FDG in hypoxia compared with the normoxic heart. FDG uptake is considered as a measure for glucose utilization; hence the higher uptake in hypoxia points to an increased glucose metabolism. This was to be expected because in hypoxia the main energy source of the normal well-oxygenated myocardium, the free fatty acids, cannot be oxidized, and the myocardium is forced to utilize glucose via the glycolytic pathway. 相似文献
90.
Luciano Callipo Anna Laura Capriotti Chiara Cavaliere Riccardo Gubbiotti Roberto Samperi Aldo Laganà 《Biomedical chromatography : BMC》2011,25(5):594-599
In proteomics experiments the first critical step after sampling is certainly sample preparation. Multidimensional chromatography techniques have emerged as a powerful tool for the large‐scale analysis of such complex samples as biological samples. In order to evaluate these separation techniques, microgram quantities of protein extracted from mouse heart tissue were fractionated by four different chromatographic methods. Regarding peptide‐level fractionation, the first dimension of separation was performed with high‐pH reversed‐phase chromatography (pH‐RP) and strong cation exchange chromatography (SCX). Regarding protein‐level fractionation, C8 protein reversed‐phase (C8‐RP Prot) and high‐recovery protein reversed‐phase (hr‐RP Prot) were used instead. The second dimension consisted of a reversed‐phase nano‐HPLC on‐Chip coupled to an electrospray ionization quadrupole time‐of‐flight mass spectrometer for tandem mass spectrometric analysis. The performance and relative fractionation efficiencies of each technique were assessed by comparing the total number of proteins identified by each method. The peptide‐level pH‐RP and the hr‐RP Prot protein‐level separations were the best methods, identifying 1338 and 1303 proteins, respectively. The peptide‐level SCX, with 509 proteins identified, was the worst method. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献