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2.
Olga A. Grishina Irina V. Kirillova Olga E. Glukhova 《Computer methods in biomechanics and biomedical engineering》2016,19(3):297-305
The biomechanical model of human coronary arteries was modified for improving the quality of diagnosis and surgical treatment for coronary heart disease. The problem of hemodynamics in the left coronary artery with multivessel bed disease – 45% stenosis of the anterior descending branch and 75% stenosis of the circumflex branch – was particularly considered. Numerical simulation of the coronary arterial bypass of the main trunk was carried out to estimate the functional condition of the coronary arteries after restoring myocardial blood supply by surgery. 相似文献
3.
急性脑梗死约占全部脑卒中的70%,病死率和致残率高,且极易复发。但目前针对急性脑梗死在时间窗内溶栓、抗凝等治疗手段不能从根本上切实有效地修复受损脑组织,且伴有出血等风险。寻找脑梗死形成发展的原因并予以治疗迫在眉睫。酸中毒是引起缺血性脑损伤的重要机制。大量实验研究表明,酸中毒能加重神经元的缺血性损伤,且其梗死面积与酸中毒的程度直接相关。但缺血产生的酸中毒如何引起神经元损伤的确切机制尚不明确。最近研究发现酸中毒能激活一种在中枢及周围神经中广泛存在的膜通道,即酸敏感离子通道,它对Ca2+通透,能引起细胞内Ca2+超载,同时能激活胞内酶引起细胞内蛋白质、脂类及核酸的降解,加重缺血后脑损伤。本文就酸敏感离子通道1a与脑梗死做一综述。 相似文献
4.
黑龙江省三江平原丹顶鹤的数量分布 总被引:2,自引:0,他引:2
在地面调查的基础上,我们使用Y-11轻型飞机对黑龙江省三江平原地区的丹顶鹤的数量分布近行了调查,调查时飞行高度80米,航速140公里/小时,续航里程共3748公里。调查结果表明,丹顶鹤在三江平原主要分布在8个地区,其中嘟噜河下游、洪河自然保护区、七星河流域和兴凯湖低地是主要繁殖地,总数量共309只。 相似文献
5.
A Zielenkiewicz W Zielenkiewicz L F Sukhodub O T Glukhova K L Wierzchowski 《Acta biochimica Polonica》1987,34(2):157-164
Enthalpies of solution in water, delta H0sol, and vant'Hoff enthalpies of sublimation, delta H0subl, were determined experimentally for a number of crystalline 2-alkyl derivatives of 9-methyladenine: m2(2,9)Ade, e2m9Ade, pr2m9Ade and but2m9Ade. Standard enthalpies of hydration, delta H0hydr derived from these data were corrected for the calculated cavity terms, delta H0cav, to yield enthalpies of interaction, delta H0int, of the solutes with their hydration shells. The apparent residual contribution of alkyl groups, R, to the enthalpy of interaction delta delta H0int (R) was found to increase linearly with the number of CH2 groups added upon alkyl substitution, whereas this contribution calculated per unit area of the water-accessible molecular surface, SB, of alkyl residues delta delta H0int (R): delta SB(R) appeared constant over the whole series of the compounds investigated. This indicates that alkyl groups substituted at the C(2) carbon atom of the adenine contribute additively to the van der Waals' part of the enthalpy of interaction and do not affect the electrostatic part of the energy of interaction of the solutes with their hydration shells. 相似文献
6.
在整理青海省蚤类标本中,发现长刺双蚤 Amphipsylla longispina Scalon, 1950一新亚种,记述如下。 长刺双蚤共和亚种 Amphipsylla longis pina gongheensis新亚种 鉴别特征 新亚种可动突前缘较直,不动突较细长,阳茎钩突端部似鸟头状; 相似文献
7.
Structural relatedness of lysis proteins from colicinogenic plasmids and icosahedral coliphages 总被引:4,自引:0,他引:4
The host-lysis-inducing functions of phi X174 protein E and MS2 protein L
were recently shown to reside on the N-terminal and C-terminal halves of
the two respective lysis proteins. In the present study it is shown that
the small lysis proteins encoded in various colicinogenic plasmids share
local sequence similarities and certain structural characteristics with the
essential peptides of their coliphage-coded counterparts. Despite their
dissimilar sizes and origins, it is suggested that the colicinogenic lysis
proteins are functionally analogous and evolutionarily related to those of
icosahedral single- stranded DNA and RNA phages.
相似文献
8.
A N Orekhov V V Tertov D N Mukhin V E Koteliansky M A Glukhova K A Khashimov V N Smirnov 《Biochimica et biophysica acta》1987,928(3):251-258
Low-density lipoproteins (LDL) were incubated with elastin particles, collagenase-resistant debris isolated from human aorta, and latex beads of 1.13 microns in diameter. As a result of incubation, insoluble LDL-associates were formed. These associates, as well as LDL-heparin-fibronectin-gelatin complexes described by other workers, were added to a 7-day primary culture of enzyme-isolated cells of human aortic subendothelial intima. The culture contained a mixed cell population made up mostly of typical and modified smooth muscle cells. 24 h later, total cholesterol, phospholipid, triacylglycerol, free cholesterol and cholesteryl ester levels were measured. Addition of insoluble LDL-complexes as well as LDL-associates to culture brought about a substantial accumulation of intracellular lipids; primarily, cholesteryl esters. The total cholesterol level in cultured cells was raised 3- to 8-fold. Addition of free LDL or LDL-free particles had no effect on the content of intracellular lipids. The results obtained allow the assumption that the occurrence of the LDL-mediated accumulation of intracellular lipids is due mainly to the LDL penetration inside the cell via 'nonspecific' phagocytosis and not through a regulated receptor-dependent pathway. 相似文献
9.
本实验在14只麻醉开胸狗心脏上观察了氟碳乳剂与右旋糖酐稀释血液对心肌耗氧量与供应缺血心肌氧量关系的影响。以左室压力-时间指数(SPTI)作为心肌耗氧量的指标,根据冠脉有效侧支血流量(ECF)、PaO_2和 Hb 浓度计算供应缺血心肌的氧量。实验结果表明,低分子右旋糖酐稀释血液后,SPTI 暂时性轻度增加(稀释后30min 时较对照增加7.1±2.7%,P<0.05,稀释后60min 时增加2.8±1.2%,P>0.05),ECF 明显增多(稀释后30min 时较对照增加58.5±6.1%,P<0.01),缺血区边缘心肌氧供需关系未发生明显变化。氟碳乳剂稀释血液后,SPTI 的变化规律与右旋糖酐稀释后相同(稀释后30min 和60min 时分别较对照增加2.5±0.7%和1.9±0.8%)ECF 和 PaO_2升高(稀释后30min 时分别较对照增加53.9±6.7%和93±8.9%),供应缺血心肌的氧量显著增加,缺血区边缘心肌氧供需矛盾明显改善。 相似文献
10.