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91.
Yonghui Qiao Yujie Zeng Ying Ding Jianren Fan 《Computer methods in biomechanics and biomedical engineering》2019,22(6):620-630
The behavior of blood cells and vessel compliance significantly influence hemodynamic parameters, which are closely related to the development of aortic dissection. Here the two-phase non-Newtonian model and the fluid-structure interaction (FSI) method are coupled to simulate blood flow in a patient-specific dissected aorta. Moreover, three-element Windkessel model is applied to reproduce physiological pressure waves. Important hemodynamic indicators, such as the spatial distribution of red blood cells (RBCs) and vessel wall displacement, which greatly influence the hemodynamic characteristics are analyzed. Results show that the proximal false lumen near the entry tear appears to be a vortex zone with a relatively lower volume fraction of RBCs, a low time-averaged wall shear stress (TAWSS) and a high oscillatory shear index (OSI), providing a suitable physical environment for the formation of atherosclerosis. The highest TAWSS is located in the narrow area of the distal true lumen which might cause further dilation. TAWSS distributions in the FSI model and the rigid wall model show similar trend, while there is a significant difference for the OSI distributions. We suggest that an integrated model is essential to simulate blood flow in a more realistic physiological environment with the ultimate aim of guiding clinical treatment. 相似文献
92.
药物滥用者红细胞免疫功能的变化 总被引:3,自引:0,他引:3
通过检测红细胞C3b受体花环(RBC-C3bRR)、红细胞免疫复合物光环(RBC-ICR)、粘附增强因子活性(RFER)及抑制因子活性(RFIR),观察了50例海洛因依赖者红细胞免疫功能的变化。结果表明,海洛因依赖者RBC-C3bRR、RFER明显下降(P<0.01),而RBC-ICR、RFIR则明显升高(P<0.01)。本文对检测结果进行了初步探讨。 相似文献
93.
本文对103例锰作业工人测定了血液流变学中的七项指标,结果表明:全血粘度(高切、低切)、血浆粘度、红细胞压积、纤维蛋白原、红细胞电泳、血小板粘附、血沉等项指标,均明显高于正常对照组(P<0.01),证实锰作业工人普遍存在高粘滞血症,为临床治疗锰中毒开辟新的途径提供了依据。对其中的52例锰中毒(包括症状较重的观察对象),用清栓酶治疗后,复查其七项指标与治疗前比较,均有明显下降(P<0.01),其症状与体征得以改善,进一步说明清栓酶是治疗锰中毒的理想药物之一。 相似文献
94.
The effect of chronic alcohol feeding on lipid peroxidation in microsomes: lack of relationship to hydroxyl radical generation 总被引:1,自引:0,他引:1
S Shaw E Jayatilleke C S Lieber 《Biochemical and biophysical research communications》1984,118(1):233-238
Chronic alcohol feeding causes microsomal induction including increased generation of hydroxyl radicals. Ethanol induced liver injury may be mediated by lipid peroxidation for which hydroxyl radicals have been proposed as major mediators. Ethanol promotes lipid peroxidation when given acutely but also may serve as a hydroxyl radical scavenger. Therefore, we studied the acute and chronic effects of alcohol on microsomal lipid peroxidation and hydroxyl radical generation. Chronic alcohol feeding in rats increased microsomal generation of hydroxyl radicals but lipid peroxidation of endogenous lipid was inversely related to hydroxyl radical generation. Ethanol (50mM) had a slight inhibitory effect on hydroxyl radical production in peroxidizing microsomes, no effect on endogenous lipid peroxidation and enhanced the lysis of RBCs added as targets of peroxidation. Enhanced microsomal generation of hydroxyl radicals following chronic alcohol feeding is not an important mediator of lipid peroxidation. 相似文献
95.
96.
Lakhu M. Keshvara Elizabeth M. Newton A. Heather Good Ole Hindsgaul Monica M. Palcic 《Glycoconjugate journal》1992,9(1):16-20
ELISA assays have been developed for (1–3)N-acetylgalactosaminyltransferase (blood group A transferase) and (1–3)galactosyltransferase (blood group B transferase) activities. In these assays, microtitre plates coated with the bovine serum albumin conjugate of a synthetic Fuc1–2Gal-R acceptor substrate are incubated with the appropriate nucleotide donor (UDP-GalNAc or UDP-Gal) and human serum as the enzyme source. The resulting trisaccharide products Fuc1–2(GalNAc1–3)Gal-R-BSA or Fuc1–2(Gal1–3)Gal-R-BSA are detected and quantified with monoclonal antibodies selected not to cross-react with the substrate structure. With less than a microliter of human serum, product formation is proportional to enzyme concentration and to time of incubation of up to 90 min. 相似文献
97.
榄香烯对急性血瘀模型大鼠血液流变性的影响 总被引:1,自引:0,他引:1
本文观察了榄香烯对急性血瘀模型大鼠血液流变性的影响。实验结果表明:榄香烯6.25-25mg/kg/d,ip×7d,可使血瘀模型鼠的高低切变率全血粘度和还原粘度、血浆粘度、血沉、红细胞聚集指数、纤维蛋白原及红细胞电泳时间等显著降低(P<0.05、P<0.01)。提示榄香烯有活血化瘀作用 相似文献
98.
Alpha-glucosidase inhibition from a Chinese medical herb (Ramulus mori) in normal and diabetic rats and mice 总被引:9,自引:0,他引:9
Alpha-glucosidase inhibitors are oral antidiabetic drugs. A traditional Chinese medical herb, Sangzhi (Ramulus mori), appears to have properties similar to those of alpha-glucosidase inhibitors. The effects of an aqueous extract of Shangzhi (SZ) were studied in normal and alloxan diabetic rats and mice, and these results compared with those for acarbose, an alpha-glucosidase inhibitor. In our grade-dose studies, SZ was found to lower and prolong the zenith of blood glucose concentration (ZBG) after sucrose or starch loading and stabilize blood glucose levels in fasting normal and alloxan diabetic mice. After 2 weeks of SZ administration with high-calorie chow or a normal diet, the fasting and non-fasting blood glucose concentrations in alloxan diabetic mice and rats were decreased. In alloxan rats, the blood fructosamine concentration was lowered. Results for acarbose and SZ were similar. These indicate that SZ has alpha-glucosidase inhibitory effects. 相似文献
99.
《Saudi Journal of Biological Sciences》2017,24(8):1879-1883
ObjectiveTo study the early predictive value of cord blood bilirubin and dynamic monitoring of transcutaneous bilirubin for hyperbilirubinemia of newborns.Methods389 newborns delivered from June 2014 to December 2015 were enrolled as the research subjects; detailed records were made about the general data of newborns and mothers, and after cord blood bilirubin being graded, the incidence of hyperbilirubinemia was counted, and the prediction efficiency of cord blood bilirubin was analyzed by receiver operator characteristic (ROC) curve. At the same time, the transcutaneous bilirubin was detected continuously when the neonate was born and 24 h, 48 h and 72 h after birth, and the relativity between transcutaneous bilirubin at 72 h and serum bilirubin was analyzed.ResultsNo significant difference was found in the hyperbilirubinemia group and the non-hyperbilirubinemia group concerning general data of the newborns and their mothers. With the concentration of cord blood bilirubin increased, the incidence of hyperbilirubinemia also increased; separate prediction of hyperbilirubinemia by cord blood bilirubin showed a sensitivity and specificity of 71.4% and 65.6% respectively, and they need further dynamic monitoring. The daily mean of transcutaneous bilirubin in hyperbilirubinemia group was significantly higher than that in non-hyperbilirubinemia group at 24 h, 48 h and 72 h, and the measurement value of transcutaneous bilirubin at 72 h had a high correlation with serum bilirubin. When transcutaneous bilirubin value is higher than 18, the incidence of hyperbilirubinemia should be considered.ConclusionsThe increase of cord blood bilirubin effectively predict the occurrence of neonatal hyperbilirubinemia. There is a good correlation between levels of transcutaneous bilirubin and serum bilirubin. Moreover, combined detection of transcutaneous bilirubin and cord blood bilirubin can significantly improve the prediction accuracy of hyperbilirubinemia. 相似文献
100.