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101.
智能化穴位温度检测仪的研制及实验研究 总被引:3,自引:0,他引:3
在经络穴位的生物物理属性中,由于皮肤温度比较灵敏,易于观察,又能及时反映该处血管的舒缩变化。作者利用铂电阻作为测温控头,用微机进行数据处理,并利用该系统进行人体皮肤温度的检测及分析。结果表明:皮肤温差点基本上是循经分布的。 相似文献
102.
103.
Poly(D,L-lactic acid) surfaces modified by silk fibroin: effects on the culture of osteoblast in vitro. 总被引:11,自引:0,他引:11
Kaiyong Cai Kangde Yao Songbai Lin Zhiming Yang Xiuqiong Li Huiqi Xie Tingwu Qing Laibao Gao 《Biomaterials》2002,23(4):1153-1160
The objective of this study was to modify the surface of poly(D,L-lactic acid) (PDLLA) with different molecular weight of silk fibroins, and assess the effects of the modified surfaces on the functions of rat osteoblasts cultured in vitro. The properties of the modified PDLLA surface and the control one were investigated by contact angle and electron spectroscopy for chemical analysis (ESCA). The former indicated the variation of hydrophilicity and the latter suggested that the modified PDLLA film using silk fibroin is enriched with nitrogen atoms. The biocompatibility of the PDLLA film may be altered and in turn affects the seeded cell functions. Therefore, attachment and proliferation of osteoblasts seeded on the modified PDLLA films and the control one were examined. Cell morphologies on these films were studied by scanning electron microscopy (SEM) and cell viability was evaluated by MTT assay. In addition, differentiated cell function was assessed by measuring the alkaline phosphatase (ALP) activity. These results suggest that the silk fibroin-modified PDLLA surface can improve the interaction between osteoblasts and the PDLLA films. 相似文献
104.
珊瑚涂层人工骨的制备及溶血实验研究 总被引:2,自引:0,他引:2
目的根据生物工程及化工等原理,制备珊瑚人工骨,并检测此珊瑚(Coral)复合人工骨的血液相容性。方法将制备的珊瑚复合人工骨、按照国际标准化组织和我国国家标准规定要求,采用将珊瑚复合人工骨及其浸提液与抗凝稀释兔血直接接触,测定红细胞释放的血红蛋白量(OD值),将测得的OD值换算为溶血率。结果珊瑚复合人工骨材料浸提液组的溶血率为1.81%,材料与血液直接接触组溶血率为1.41%,阴性对照组和阳性对照组溶血率分别为0%、100%。结论珊瑚复合人工骨材料无溶血作用,血液相容性良好。 相似文献
105.
Modified muscle use can result in muscle inflammation that is triggered by unidentified events. In the present investigation, we tested whether the activation of the complement system is a component of muscle inflammation that results from changes in muscle loading. Modified rat hindlimb muscle loading was achieved by removing weight-bearing from the hindlimbs for 10 days followed by reloading through normal ambulation. Experimental animals were injected with the recombinant, soluble complement receptor sCR1 to inhibit complement activation. Assays for complement C4 or factor B in sera showed that sCR1 produced large reductions in the capacity for activation of the complement system through both the classical and alternative pathways. Analysis of complement C4 concentration in serum in untreated animals showed that the classical pathway was activated during the first 2 hours of reloading. Analysis of factor B concentration in untreated animals showed activation of the alternative pathway at 6 hours of reloading. Administration of sCR1 significantly attenuated the invasion of neutrophils (-49%) and ED1(+) macrophages (-52%) that occurred in nontreated animals after 6 hours of reloading. The presence of sCR1 also reduced significantly the degree of edema by 22% as compared to untreated animals. Together, these data show that increased muscle loading activated the complement system which then briefly contributes to the early recruitment of inflammatory cells during modified muscle loading. 相似文献
106.
Tissue-specific homing receptor mediates lymphocyte adhesion to cytokine-stimulated lymph node high endothelial venule cells. 总被引:1,自引:0,他引:1 下载免费PDF全文
Lymphocytes bind to high endothelial venule (HEV) cells as the first step in the migration of these cells into lymph nodes (LN) and Peyer's patches (PP). In this study we isolated and cultured HEV cells from rat LN and investigated the effects of cytokines on the adhesiveness of these cells for lymphocytes. The results showed that lymphocytes from thoracic duct, spleen and LN adhered preferentially to the cultured LN HEV cells compared to cells isolated from the thymus and bone marrow. The adhesiveness of LN HEV cells for thoracic duct lymphocytes (TDL) was significantly increased in a dose- and time-dependent manner by pretreatment of the HEV cells with tumour necrosis factor-alpha (TNF-alpha), interferon-gamma (IFN-gamma) or interleukin-4 (IL-4). In contrast, pretreatment of HEV cells with IL-1, IL-6 or IL-7 did not alter the capacity of LN HEV cells to adhere lymphocytes. Furthermore, incubation of LN HEV cells with suboptimal doses of TNF and IL-4, IFN-gamma and IL-4, or TNF-alpha and IFN-gamma increased significantly the endothelial adhesiveness. Interestingly, although IL-1 alone did not promote the adhesiveness of HEV cells, the cytokine synergized with suboptimal doses of IL-4 and TNF-alpha to increase the adhesiveness. The adhesion of TDL to non-stimulated and IL-4-stimulated LN HEV cells could be blocked specifically by treatment of lymphocytes with the LN homing-receptor-specific A.11.5 monoclonal antibody (mAb). In contrast, lymphocytes pretreated with the PP-homing receptor-specific 1B.2.6 mAb or the antileucocyte common antigen (OX1) mAb adhered normally to the HEV cells. Taken together, these results indicate that the baseline and cytokine-stimulated bindings between lymphocytes and LN HEV cells are mediated by adhesive mechanisms that regulate lymphocyte migration into LN in vivo and provide strong evidence that cytokines are central mediators of organ-specific lymphocyte migration. 相似文献
107.
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
108.
Prakash N. Rao PhDa f Xin Cai MDa f Raman Venkataramanan PhDb Jeffrey L. Platt MDd Anthony Demetris MDa c Allen Thunberg MDe Connie Faltynek PhDe Thomas Starzl MD PhDa Prem Kumar MDf 《The Journal of allergy and clinical immunology》1995,95(6)
Reperfusion after ischemia results in endothelial cell injury and Kupffer cell activation. Inflammatory cytokines thus released can induce major histocompatibility complex antigens and increase the immunogenecity of the graft. An orthotopic rat liver allotransplant model was used to test the hypothesis that prevention of reperfusion injury by infusion of polyethylene glycol superoxide dismutase (PEG-SOD) would result in long-term allograft survival in the presence of subthreshold immunosuppressive dosages. ACI rats were used as donors, and Lewis strain rats as recipients. Orthotopic liver transplantation was initially performed to identify a subthreshold dose of the immunosuppressant FK-506, which would be unable to extend survival longer than control untreated rats with this strain combination. After testing three intramuscular FK-506 doses of 0.04, 0.08, and 0.16 mg/kg, it was observed that an FK-506 dose of 0.04 mg/kg/day for 14 days was unable to extend survival longer than in untreated recipients. This dose of FK-506 was used in combination with PEG-SOD at doses of 1000, 3000, 10,000, or 30,000 units. Recipient animals were treated intravenously with PEG-SOD as a loading dose to facilitate tissue penetration on day 1, and beginning on the day of transplantation, every 2 days for the duration of the study. Results of histologic studies and mean survival time were compared in untreated recipients and in rats treated with PEG-SOD plus 0.04 mg/kg/day FK-506. Mean survival time was increased significantly in these animals (p < 0.007) to 40.6 ± 25.6 days as compared with either untreated rats (10.0 ± 2.7 days) or rats treated with 0.04 mg/kg FK-506 alone (13.7 ± 4.2 days). Histologic examination demonstrated a significant reduction in the cellular infiltrate in rats treated with PEG-SOD plus FK-506, as compared with recipients treated with either agent alone or left untreated. Our results therefore suggest a potential approach to reducing immunosuppression in transplantation. (J ALLERGY CLIN IMMUNOL 1995;95:1276-81.) 相似文献
109.
本实验比较了川芎嗪对不同段的肺血管的舒张作用,结果表明川芎嗪对肺实质内动脉的舒张作用比肺实质外动脉强,内皮细胞能促进川芎嗪对肺动脉的舒张作用。 相似文献
110.