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31.
将一种快速、灵敏、可靠、简便的抗癌活性微量测定技术——~3H—TdR前体掺入技术用于复方中药抗癌制剂制备工艺筛选,短期内即拟定出较合理的工艺,经临床及14项生物学指标综合评定,该制剂疗效好,无明显的毒副作用。表明把一些快速、灵敏的医学检测技术引入药物制备工艺、质量标准及稳定性研究,可克服由于活性成分不清楚带来的一些困难,拓宽了研究途径,提高了研究水平。 相似文献
32.
33.
T2毒素在灌流大鼠肠肝中的首过效应和代谢动力学 总被引:3,自引:0,他引:3
建立并用大鼠在体肠-肝灌流标本研究了T2毒素在大鼠肠肝中的首过效应和代谢转化动力学,T2毒素在大鼠肠肝中的主要代谢产物是HT2,3′-OHHT2和其葡萄糖醛酸结合物,T2毒素具有显著的肠肝首过效应,当毒素(42μg·ml~(-1))由上肠系膜动脉恒速单次灌流(8 ml·min~(-1))肠-肝标本时,穗态肝、肠抽提率分别为0.978和0.454,总有效清除率为7.91 ml·min~(-1),T2毒素在循环灌流大鼠肠-肝标本中的消除半衰期为6.5min,主要代谢产物HT2,3′-OHHT2的生成半衰期分别为8.5和38.5 min,结果表明,T2毒素经消化道中毒后,在肠和肝的首过代谢下能很快地转化为产物,因此,毒素在体内的毒效作用主要由其代谢产物表现出来。 相似文献
34.
T. Ishikawa T. Yagi H. Sadamori N. Ishine H. Sasaki M. Oishi N. Tanaka 《Transplant international》1998,11(S1):S410-S416
Abstract This study was designed to investigate the effects of differences in the route of nutritional support of the donor on cold ischemia/reperfusion injury. Participation of Kupffer cells in these effects, based on the analysis of hepatic energy metabolism in early phases of reperfusion was also investigated. Orthotopic liver transplantation was performed between Large-White pigs weighing 20–30 kg after a 4-h cold preservation of the graft in Euro-Collins solution at 4°C. One group was fed orally with a standard laboratory diet (FED group, n = 5), a second group was fasted and given 20% glucose intravenously (12 kJ/kg per day) (PEF group, n = 5), and a third group was fed orally with a standard laboratory diet and given GdCI3 (10 mg/kg) intravenously 24 h before operation (FEDGD group, n = 5). These treatments were given for 7 days prior to harvesting. The survival time was significantly longer in the PEF (34.8 ± 5.5 days) and FEDGD (28.0 ± 11.9 days) groups than in the FED (9.8 ± 2.0 days) group ( P < 0.05). The serum hyaluronic acid elimination rate determined from 1 to 2 h after reperfusion was significantly lower in the FED group than in the other two groups ( P < 0.001). The glycogen content of the livers 1 h after reperfusion in all three groups had been consumed rapidly, but the ATP content of the livers was significantly reduced in the FED group alone ( P < 0.01). Hepatic FFA clearance (CFFA ) was moderately increased in all three groups in the early phase after reperfusion, but it was higher in the FED group than in the other two groups, with significant differences 1 and 2 h after reperfusion ( P < 0.05). In conclusion, parenteral nutrition of the donors reduced cold ischemia/reperfusion injury which is related to Kupffer cell activation and, thus, was better than enteral nutrition for donor management. 相似文献
35.
36.
The energy cost of walking or running on sand 总被引:1,自引:0,他引:1
Zamparo P. Perini R. Orizio C. Sacher M. Ferretti G. 《European journal of applied physiology》1992,65(2):183-187
Summary Oxygen uptake (
O2) at steady state, heart rate and perceived exertion were determined on nine subjects (six men and three women) while walking (3–7 km · h–1) or running (7–14 km · h–1) on sand or on a firm surface. The women performed the walking tests only. The energy cost of locomotion per unit of distance (C) was then calculated from the ratio of
O2 to speed and expressed in J · kg–1 · m–1 assuming an energy equivalent of 20.9 J · ml O2
–1. At the highest speedsC was adjusted for the measured lactate contribution (which ranged from approximately 2% to approximately 11% of the total). It was found that, when walking on sand,C increased linearly with speed from 3.1 J · kg–1 · m–1 at 3 km · h–1 to 5.5 J · kg–1 · m–1 at 7 km · h–1, whereas on a firm surfaceC attained a minimum of 2.3 J · kg–1 · m–1 at 4.5 km · h–1 being greater at lower or higher speeds. On average, when walking at speeds greater than 3 km · h–1,C was about 1.8 times greater on sand than on compact terrain. When running on sandC was approximately independent of the speed, amounting to 5.3 J · kg–1 · m–1, i.e. about 1.2 times greater than on compact terrain. These findings could be attributed to a reduced recovery of potential and kinetic energy at each stride when walking on sand (approximately 45% to be compared to approximately 65% on a firm surface) and to a reduced recovery of elastic energy when running on sand. 相似文献
37.
Previous work in our laboratory has shown that neural trauma results in a disparity between oxidative and glycolytic rates. In non-neural tissue, glycolysis and oxidative phosphorylation have been shown to work independently of one another, a phenomenon known as "energy compartmentalization". We believe that functional compartmentalization of energy production may also occur in the brain with glycolysis providing energy for membrane bound ionic pumps. Spreading depression, induced in rodent brain by topical KCl application, results in K+ shifts. The restoration of K+ gradients is accomplished by energy dependent Na(+)-K+ pumps. If these pumps depend upon glycolysis, blocking glycolysis should prevent reconstitution of normal [K+]e levels. The present series of experiments were designed to suggest that energy compartmentalization may also exist in brain, and that glycolytic energy production is preferentially used by Na(+)-K+ pumps to maintain normal ionic homeostasis by observing the dynamics of spreading depression induced K+ shifts before and after glycolytic blockade. Spreading depression was associated with increased K+ (48.6 +/- 16.6 mM over control) that normalized within 2.9 +/- 0.3 minutes. Following superfusion with a glycolytic blocking agent, spreading depression produced similar increases in [K+]e (40.6 +/- 12.0 mM over control) but time for reconstitution of the normal [K+]e was 400% longer than controls (2.9 +/- 0.3 to 14.9 +/- 2.1 minutes, P less than 0.001). Time required for recovery of EEG was identical pre- and post-blockade. We believe these data suggest that energy compartmentalization may exist in neural tissue and that glycolytic pathways of energy production are functionally tied to membrane Na(+)-K+ pumps.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
38.
Summary A simple model of the thorax, pelvis and three columns of the intrinsic lumbar back muscles (=ILBM) was constructed. The model was used to study the length of the ILBM during the different stages of the walking cycle. The length of the right ILBM (especially the lateral column) was largest at right toe off, exactly the stage of the walking cycle in which most force was needed to prevent the torso from falling forwards and laterally. 相似文献
39.
H. Baharestani W. J. Tompkins J. G. Webster R. B. Mazess 《Medical & biological engineering & computing》1979,17(6):719-723
We describe the design of an instrument that can acquire and store the average heart rate of a subject over 256 time intervals
of predetermined length (1 or 6 min) during normal daily activities. The instrument consists of two units: a portable recorder,
worn by the patient, detects and counts heart beats, and stores their average in memory, and a display later retrieves the
contents of that memory. C.M.O.S. technology and programmable operational amplifiers resulted in low power consumption (20
mW). The results obtained from this instrument were accurate to about 1 beat/min compared with Holter monitoring and telemetry. 相似文献
40.
光化学诱导的血栓形成性脑缺血及其代谢改变 总被引:4,自引:2,他引:4
本文用光化学法激发大鼠局部脑血栓形成,以组织病理学、局部脑血流量、皮层水含量、三磷酸腺苷、二磷酸腺苷,一磷酸腺苷、能量负荷、肌酸及乳酸为指标,探讨局部脑血栓形成后5天rCBF明显增高的可能机理。结果表明,血栓形成后局部脑组织ATP水平进行性减少(P<0.01)、ADP/ATP及AMP/ATP比值明显升高(P均<0.01),LA及脑水含量显著增加(P<0.01)。这些因素既是能量衰竭、无氧酵解的结果 相似文献