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31.
Social isolation stress augments angiogenesis induced by colon 26-L5 carcinoma cells in mice 总被引:3,自引:0,他引:3
Wu W Murata J Murakami K Yamaura T Hayashi K Saiki I 《Clinical & experimental metastasis》2000,18(1):1-10
We have previously shown that tumor necrosis factor-α (TNF-α), which is an important angiogenesis-related factor, was over-secreted in male BALB/c mice under social isolation stress as compared with the control, and closely associated with a remarkable elevation of tumor invasion and metastasis of colon 26-L5 carcinoma cells. In the present study, we explored the effect of isolation stress on the angiogenesis caused by colon 26-L5 carcinoma cells in vivo and in vitro. Social isolation lead to the enhancement of tumor growth after intrahepatic implantation with a fragment of colon 26-L5 tumor. Angiogenic response (number of vessels oriented towards tumor mass) and tumor growth (size) were significantly increased in the socially isolated mouse relative to that in the group-housed mice. Furthermore, higher protein level of hepatic TNF-α was found in the stressed mice than that in the control. Expression of mRNA for vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) were also elevated in the tumor regions and liver tissues of the stressed mice in comparison with that in group-housed mice. On the other hand, hepatic sinusoidal endothelial (HSE) cells treated with TNF-α exhibited a marked promotion of the migration, invasion, expression of mRNA for matrix metalloproteinase (MMP)-9, and tube-like formation, but no cytotoxicity against the cells in vitro. The above data suggest that the social isolation stress augmented the tumor-induced angiogenesis probably by up-regulating the angiogenesis-related factors, including TNF-α, VEGF and HGF, and consequently mediating the functions of endothelial cells such as migration, invasion, and tube-like formation. 相似文献
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Teresa Sagalés Victor Gimeno M. Dolores de la Calzada Francesc Casellas M. Dolors Macià M. Villar Soriano 《Brain topography》1990,2(3):221-228
Summary Topographical analysis of cerebral electrical activity was performed in 44 patients with hepatic encephalopathy. These patients were classified in 5 groups according to clinical criteria. Eight healthy subjects were used as a control group. All were studied in an awake, eyes closed, condition and some [Control Group (CG), Group 0 (G0), Group 1 (G1) and Group 2 (G2)] also in an awake, eyes open, condition. The awake, eyes closed, maps showed marked differences in the power spectral density (PSD) of the different bands, when comparing normal subjects with patients with several degrees of hepatic encephalopathy. These differences were related to the degree of clinical involvement, mainly in the alpha and delta PSD bands. The combination of a decreased alpha PSD, increased delta PSD, and decreased mean dominant frequency (MDF) allowed a clear discrimination between the different clinical groups. The differences observed between awake, eyes closed, and awake, eyes open, conditions were especially helpful to discriminate between CG subjects and G0, G1 and G2 patients. 相似文献
35.
利用光镜、电镜、免疫组化和形态学定量技术动态研究维生素A对大鼠四氯化碳肝纤维化的抑制作用。结果表明,维生素A可减少四氯化碳中毒大鼠肝内纤维连接蛋白和Ⅰ、Ⅲ型胶原沉积,抑制贮脂细胞向成纤维细胞转化,并可明显地减轻肝纤维化程度。本文还对维生素A抑制肝纤维化的机理及意义作了初步探讨。 相似文献
36.
Sven-Erik Larsson Hongming Cai P. Åke Öberg 《European journal of applied physiology》1993,66(6):483-488
Summary Microcirculation in the upper portion of the trapezius muscle was measured percutaneously by continuous laser-Doppler flowmetry (LDF) during two 10-min series of alternating 1-min periods of static contraction and rest determined electromyographically (EMG). Stepwise increased contraction was induced by keeping the arms straight and elevated at 30, 60, 90 and 135°, which was repeated with a 1-kg load carried in each hand. Thereafter, fatigue and recovery were recorded while the subject kept her arms straight and elevated at 45° carrying the 1-kg hand load as long as possible, followed by rest with arms hanging and no load. A group of 16 healthy women of different ages was studied. Signal processing was done on line using a 386 SX computer. The LDF- and root-mean-square (rms) EMG signals were normalized. Spectrum analyses of EMG mean power frequency (MPF) and median spectrum frequency were performed. The rms-EMG increased significantly with an increase in the calculated shoulder torque (r=0.75). Accumulated local fatigue was indicated by a decrease in MPF with increased shoulder angle and added load (r = –0.54). Blood flow increased with increased shoulder angle (r=0.82, with hand loadr=0.62) and with increased shoulder torque (r=0.72), and also showed a significant increase with increased EMG activity (r=0.74). The LDF showed a negative correlation to MPF (r= –0.67), with increased values when MPF was lowered. During the endurance test, a moderate increase of LDF occurred which reached its maximum during the 1st min of recovery. Then, a slow return to the base level was recorded. The ability to increase the flow in the microcirculation with increasing muscle load was not diminished with age. 相似文献
37.
经皮穿刺椎间盘髓核摘除术入路的研究 总被引:1,自引:0,他引:1
为提供椎间盘髓核摘除术形态学依据,在7具成人横断面标本上观察测量了L1~L5椎间盘平面经皮穿刺椎间盘髓核摘除术的进针点、角度和深度。发现在L1~L3、L4~L5椎间盘髓核的穿刺点以距后正中线8~10cm,9~11cm,穿刺角度以46.7°~59.5°,穿刺深度为110.2~128.9mm为最宜。 相似文献
38.
Units which are activated by ascending impulses from the liver within the nucleus of the solitary tract (NTS) were identified by electrical stimulation delivered to the hepatic branch of the vagus. Responses of descending units were eliminated by a collision test. The units which showed decreased firing rates during portal infusion of isotonic glucose solution were also glucose-sensitive so that they showed decreased firing rates during topical application of glucose by means of micro-electro-osmotic techniques. It is concluded that glucose-sensitive neurons exist within the NTS and also that they are functionally linked with hepatoportal glucose-sensitive afferent units. 相似文献
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冠脉内支架临床发展策略 总被引:1,自引:0,他引:1
董为人 《生物医学工程学杂志》1997,14(2):156-163
冠脉内支架是临床上预防PTCA并发症的有效措施,但金属支架固有的血栓菜成原性和对血管壁组织的永久性刺激可导致院内心脏事件和再狭窄。为解决上述问题,作者提出,血管内支架联合靶向药物传输离子照射或基因治疗、基因修饰的内皮细胞的种植支架、吱物可吸收缓释药物支架材料研制为临床冠脉内支架开辟了广阔的发展前景。 相似文献