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H Ikenaga T Ogihara S Iyori S Kou H Yoshikawa M M Okura 《Postgraduate medical journal》1989,65(768):761-764
A case of a young Japanese woman with long-standing ulcerative colitis complicated by preinfarction angina due to Takayasu's aortitis is presented. Successful emergency aorto-coronary bypass operation was performed. Whether the association of these two diseases can be explained by a common mechanism is discussed. 相似文献
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根据热分析谱图峰顶的数学特征与Coats-Redfern方程,推得在一定实验条件下,在系列相关反应中,若峰顶温度相接近,则各反应的表观活化能E与指前因子A之间存在着有动力学意义的补偿效应,即lnA=aE+b。并经系列含水硫酸盐脱水反应实验验证。 相似文献
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Sinko P. J. Leesman G. D. Waclawski A. P. Yu H. Kou J. H. 《Pharmaceutical research》1996,13(4):570-576
Purpose. To develop, validate and apply a method for analyzing the intestinal perfusion data of highly permeable compounds using the Numerical Aqueous Resistance (NAR) theory and nonlinear regression (NAR-NLR) and to compare the results with the well-established Modified Boundary Layer (MBL) Analysis.
Methods. The NAR-NLR method was validated and the results were compared to the MBL analysis results using previously reported cephradine jejunal perfusion data. Using the Single Pass Intestinal Perfusion (SPIP) method, the concentration dependence of intestinal permeability was investigated for formycin B, proline, and thymidine, three compounds reported to be absorbed by carrier-mediated transport processes. The MBL and NAR-NLR analyses were then applied to the three sets of SPIP data.
Results. The results demonstrate that the intrinsic MBL transport parameters were highly variable and, in one case, the analyses failed to give a statistically significant Michaelis constant. The MBL mean dimensionless wall permeabilities (P*w) were greater than the NAR-NLR P*w and were also highly variable. In all cases, the NAR-NLR variability was significantly lower than the MBL variability. The extreme variability in the MBL-calculated P*w is due to the sensitivity of P*w when the fraction of unabsorbed drug (Cm/Co) is low or, alternatively, when P*w approached the aqueous permeability, P*aq.
Conclusions. The NAR-NLR method facilitates the analysis of intestinal perfusion data for highly permeable compounds such as those absorbed by carrier-mediated processes at concentrations below their Km. The method also allows for the use of a wider range of flow conditions than the MBL analysis resulting in more reliable and less variable estimates of intestinal transport parameters as well as intestinal wall permeabilities. 相似文献
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Abe Y Chinzei T Isoyama T Kobayashi S Ono T Saito I Iwasaki K Ishimaru M Baba A Kouno A Ozeki T Tohyama T Imachi K 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2003,49(3):325-332
The undulation pump total artificial heart (UPTAH) is a unique, implantable, total artificial heart (TAH) that uses undulation pumps. To achieve long-term survival in animals with physiologic hemodynamic conditions, a control method based on conductance and arterial pressure was applied to UPTAH. With this control method, called 1/R control, survival periods of 50 days (No. 0016, 49.6 kg) and 54 days (No. 0030, 42.5 kg) were obtained in adult female goats. In No. 0016, 1/R control was applied to the left pump, whereas in No. 0030, it was applied to the right pump. Another pump was used for left-right balance control. The control stability was better in No. 0030 than in No. 0016. The sucking effect of the left atrium was remarkable in No. 0016, possibly because of a time delay when left-right balance control was performed with the right pump. In No. 0016, the cause of death was probably a thrombus flown from a panus in the left atrium. It is possible that the left atrial suction effect influenced the thrombus and panus formation in the left atrium. In No. 0030, the cause of death was a small rupture of the membrane in the right pump. The rupture may have been caused by excessive negative pressure inside the pump. This pressure resulted from suction of the right atrium because of an unexpected control excursion, which was probably caused by a software bug. It will be necessary to redesign the undulation pump and improve the software to achieve longer survival periods for animals with physiologic hemodynamic conditions. 相似文献
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Substance P (SP) belongs to a group of peptides called tachykinins. Biological effects of SP are mediated by tachykinin receptors that have been classified as neurokinin-1 (NK-1), NK-2 and NK-3 subtypes. The aim of the present study is to elucidate the tachykinin receptor subtype(s) that mediate the excitatory effects of SP in the carotid body. For this purpose, we compared the carotid body responses elicited by SP with that of physalaemin and eledoisin. In other tissues, physalaemin exhibits equi or greater potency at NK-1 receptors and eledoisin exerts its effects more on NK-2 and NK-3 subtypes compared to SP. Experiments were performed on eight cats that were anaesthetized, paralyzed and artificially ventilated with room air. Close carotid body administration of SP and physalaemin produced dose-dependent augmentation of the chemoreceptor afferent activity. Chemoreceptor discharge, however, was unaffected by eledoisin. Compared to that by SP, the magnitude of excitation produced by physalaemin was the same at lower doses but significantly greater with the highest dose (100 nmol). The time course of the response induced by physalaemin, however, was the same as that by SP. The present results demonstrate that in the carotid body physalaemin is also either equi or relatively more potent than SP, whereas eledoisin has no effect on the chemoreceptor discharge. It is suggested that stimulation of the carotid body by SP is mediated by NK-1 but not NK-2 or NK-3 receptors. 相似文献
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目的观察长链非编码RNA Linc00472(LncRNA Linc00472)靶向调控微小RNA-381(miR-381)对骨肉瘤细胞增殖、凋亡、迁移、侵袭的影响。方法收集2017年3月至2018年5月郑州大学第一附属医院收治的骨肉瘤患者29例为研究对象,实时荧光定量聚合酶链反应(RT-qPCR)检测骨肉瘤组织和瘤旁组织中Linc00472的表达。将骨肉瘤U2OS细胞分为pcDNA3.1组、pcDNA3.1-Linc00472组、pcDNA3.1-Linc00472+miR-NC组、pcDNA3.1-Linc00472+miR-381组。甲基噻唑基四唑(MTT)检测细胞增殖;流式细胞术检测细胞凋亡;Transwell实验检测细胞迁移及侵袭。双荧光素酶报告实验鉴定Linc00472与miR-381的靶向关系。两组间比较采用独立样本t检验,多组间比较采用单因素方差分析。结果Linc00472在骨肉瘤组织中的表达水平低于瘤旁组织(0.31±0.03比1.03±0.10,t=37.138,P<0.05),差异有统计学意义;与pcDNA3.1组比较,pcDNA3.1-Linc00472组细胞存活率[(100.29±10.12)%比(53.29±5.44)%]低于pcDNA3.1组(t=12.272,P<0.05),差异有统计学意义,迁移细胞数[(266.00±23.61)个比(124.00±12.01)个]与侵袭细胞数[(131.00±13.06)个比(62.00±6.24)个]少于pcDNA3.1组(t=16.082,P<0.05;t=14.301,P<0.05),差异有统计学意义,而细胞凋亡率[(8.58±0.91)%比(26.61±2.64)%]高于pcDNA3.1组(t=19.370,P<0.05),差异有统计学意义;miR-381过表达可抑制野生型载体WT-Linc00472细胞的荧光素酶活性(t=19.827,P<0.05),差异有统计学意义;与pcDNA3.1-Linc00472+miR-NC组比较,pcDNA3.1-Linc00472+miR-381组可增强细胞增殖[(53.17±5.33)%比(85.26±8.62)%]、迁移[(122.00±12.31)个比(223.00±22.18)个]及侵袭[(64.00±6.36)个比(104.00±10.20)个]能力高于pcDNA3.1-Linc00472+miR-NC组(t=9.499,P<0.05;t=11.945,P<0.05;t=9.983,P<0.05),细胞凋亡率[(26.11±2.62)%比(13.11±1.34)%]低于pcDNA3.1-Linc00472+miR-NC组(t=13.253,P<0.05),差异有统计学意义。结论LncRNA Linc00472通过靶向调控miR-381可抑制骨肉瘤细胞增殖、迁移及侵袭并诱导细胞凋亡。 相似文献