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11.
Phytate was digested by wheat bran phytase to yield inositol tetrakisphosphate. Periodate-oxidized inositol tetrakisphosphate (oxyIP4) was coupled by means of reductive alkylation to hemoglobin and the covalent dextran-hemoglobin conjugate to yield the rightshifted (rs) compounds rsHb and rsDxHb, respectively. The variations of the oxygen dissociation curves of these molecules with pH and temperature were compared to those of hemoglobin. The variations with pH were found to be less pronounced for these rightshifted forms. An extensive decrease in the half-saturation oxygen tension was observed, however, with both rsHb and rsDxHb, as in the case of unmodified Hb. Modification of hemoglobin by oxyIP4 at the polyphosphate site was suggested by the lack of a further rightshifting effect of phytate on rsHb, and by the similarity between the difference spectrum of rs-methemoglobin and the difference spectrum induced by the addition of phytate. 相似文献
12.
Martins K Ahrenholz P Matic GB Hofmann D Tiess M Winkler RE Ramlow W 《Artificial organs》2000,24(7):526-532
Release of microparticles into the blood during extracorporeal circulation must be kept low because of possibly serious acute and chronic adverse effects. Concentration and size distribution of microparticles were measured during simulated treatments (n = 7) on original equipment for 2 standard low-density lipoprotein (LDL) elimination procedures (DALI 750, Fresenius AG, St. Wendel, Germany and Liposorber, Kaneka Corporation, Osaka, Japan) and compared to hemofiltration solutions. For both systems as well as in hemofiltration solutions, the mean particle concentrations in 500 ml portions gathered from the efferent blood line stayed below 10% of pharmacopoeia standards for infusion solutions (United States Pharmacopoeia, European Pharmacopoeia) in all measured size classes. Although particle concentrations were comparable in all systems, the mean total number of particles > or =2 microm released per session was lowest in the DALI (167,000) compared to the Liposorber (465,000) and hemofiltration solutions (2,240,000). This was mainly due to different total processed blood volumes necessary to achieve the required LDL reduction. 相似文献
13.
磁转染MUC1/Y基因入树突状细胞抗膀胱肿瘤的免疫效应研究 总被引:3,自引:1,他引:2
目的:研究体外磁转染人MUC1/Y基因至人树突状细胞(DC)的可行性,以及在体外诱导特异忡抗MUC1/Y膀胱癌的免疫效应。方法:以葡聚糖磁性纳米颗粒(DMN)作为载体,在多聚赖氨酸(PLL)的辅助下,通过静电作用结合MUC1/Y基因的真核表达载体pEGFP-C1—MUC1/Y.在铜-硼-锡磁块的固定磁场作用下转染至人DC中,荧光显做镜下以及流式细胞仪观察其转染效率;再将这种转基因DC与自体T细胞共培养,观察其致敏的细胞毒性T淋巴细胞(CTL)对MUC1/Y特异性抗膀胱癌(膀胱肿瘤BIU87细胞系)的杀伤活性,即分别用LDH释放法检测CTL杀伤活性和透射电镜观察CTL诱导靶细胞凋亡情况:ELISA法测定基冈修饰后的DC刺激自体T细胞分泌IFN-γ了的能力。结果:pEGFP-C1/-MUC1/Y转染效率为15%左右,荧光显微镜下可观察到明显绿色荧光蛋白的表达;与自体T细胞混合培养后能诱导出湿著的MUC1/Y特异性的CTL对BIU87细胞的杀伤实验表明T-DC-MUC1的杀伤活性约为52%,显著高于埘照组T-DC诱导的CTL;住透射电镜下也可以清楚的观察到部分BIU87膀胱肿瘤细胞出现了细胞核核仁消失,染色质浓集于核膜周围等早期凋亡表现;基因修饰后的DC能刺激自体T细胞分泌高水平的IFN-γ,与未转染的DC相比差异有统计学意义(P〈0.05)。结论:葡聚糖磁性纳米颗粒(DMN)在固定磁场的作用下成功将MUC1/Y基因转入DC,并可有效诱导出特异性的抗MUC1/Y膀胱癌的免疫效应。 相似文献
14.
目的观察丹龙醒脑片时血瘀证犬血液流变性和球结膜微循环的影响,以探讨其活血化瘀功效。方法从后肢大隐静脉注射高分子右旋糖苷复制血瘀证犬模型,观察其血液流变性和球结膜微循环改变以及丹龙醒脑片对该模型的影响。结果造模后,模型组全血粘度、全血还原粘度和血浆粘度显著升高,血沉和血沉方程K值升高,红细胞聚集指数和红细胞变形指数明显升高;球结膜微循环形态积分和流态积分明显增高(P<0.01-0.05)。与模型组相比,丹龙醒脑片大中剂量组全血粘度、全血还原粘度,血浆粘度、血沉方程K值、红细胞聚集指数、红细胞变形指数显著降低,球结膜微循环形态积分和流态积分亦显著降低(P<0.01-0.05)。结论丹龙醒脑片能改善高分子右旋糖苷所致血瘀证犬模型血液流变性,改善微循环障碍。这可能是其活血化瘀作用的机制之一。 相似文献
15.
目的:探讨当归注射液对急性微循环障碍大鼠淋巴微循环的作用.方法:Wistar大鼠16只,随机分成2组(n=8),用分子右旋糖酐(Dextran 500)诱导大鼠急性微循环障碍,观察当归注射液对肠系膜淋巴微循环的影响.结果:大鼠注射Dextran 500后,肠系膜淋巴微循环出现明显障碍;当归注射液可明显扩张肠系膜淋巴管,增强淋巴管收缩幅度,延长舒张期时间,其作用明显优于NS(P<0.05).此外,当归注射液可使肠系膜淋巴管收缩指数L.D-Index明显升高.结论:当归注射液能明显改善急性微循环障碍大鼠的淋巴微循环障碍. 相似文献
16.
成人颅脑CT低剂量扫描参数的优化研究 总被引:2,自引:0,他引:2
目的探讨成人颅脑CT低剂量扫描的可行性及适当的扫描参数。方法采用模体应用研究和临床验证的方法,通过调整扫描参数(mAs),对Catphan 500 CT性能模体进行多次扫描,对扫描的图像进行高对比分辨率、低对比分辨率、图像噪声及均匀性评价,依据诊断要求确定颅脑CT低剂量扫描参数,分别以常规扫描参数、低剂量扫描参数对成年志愿者进行CT扫描,并对相应的图像质量作出评价,应用统计学软件进行分析。结果降低毫安秒,图像噪声增加,图像低对比分辨率下降,CT剂量呈线性降低;低剂量扫描参数(120 kV,100 mAs)完成的志愿者CT图像可以满足诊断要求。结论对成年脑外伤、脑出血、大面积脑梗死等病情复查的患者进行低剂量扫描是可行的,以实验的方式扫描Catphan 500 CT性能模体能够确定出患者低剂量扫描的参数。 相似文献
17.
Güne
N. Ege 《Seminars in nuclear medicine》1983,13(1):26-34
Radiocolloid lymphoscintigraphy is a versatile, simple technique which has been utilized extensively in the assessment of lymphatic function and structure in anatomic regions accessible to neither clinical examination nor radiocontrast lymphography, as well as in circumstances where radiocontrast lymphography is not feasible. The most important requirement for an effective study are: (a) Determination of the appropriate injection site for reproducibly visualizing the majority of the lymphatics under study and, (b) use of an agent with the optimum properties of a preformed small, uniform, well-dispersed particle colloid. Multiple applications of lymphoscintigraphy in the patient with breast carcinoma have demonstrated its value in distinguishing abnormalities of the internal mammary lymphatics shown to have significant prognostic implications, in providing accurate localization of the parasternal lymphatics for radiation therapy and its potential for determining the status of axillary lymphatics in lieu of surgical intervention. The following review is based on an experience of over 6500 studies in 5550 patients with breast carcinoma. 相似文献
18.
Shi Lijie Shi Lei Liu Leilei Feng Xiuxian Wang Jing Yang Qiang Chai Shiwei Gou Jing Zang Fenglin He Sufei 《中医杂志(英文版)》2017,37(4):452-460
Objective
To evaluate the effect of decoction prepared with Yang-activating and stasis-eliminating medicinals from Traditional Chinese Medicine (TCM) on the intestinal mucosal permeability in rats with ulcerative colitis induced by dextran sulfate sodium (DSS).Methods
Totally 55 male Wistar rats (body weight of 170–190 g) were randomly divided into the blank group (n = 10) and the model duplication group (n = 45). The blank group was not intervened, while the other was modeled with 5% dextran sulfate sodium by gavaging in a dosage of 4 mL per day to induce ulcerative colitis, a total of 7 days. Then, the model rats were divided into model blank group, mesalazine group and TCM group, and each group was consisted of 15 rats. They were given retention enema 10 min with normal saline, mesalazine enema (0.036 g/mL), and Yang-activating and stasis-eliminating decoction [0.54 g/mL of a decoction boiled by Puhuang (Pollen Typhae), Xiebai (Bulbus Allii Macrostemonis) and Wulingzhi (Faeces Trogopteri)] for 10 days respectively. Afterwards, all of the rats were evaluated by disease activity index (DAI), histological changes of distal colon, expression of occludin protein and ultrastructure of intestinal epithelial cells. Furthermore, ratio of lactulose to mannitol (L/M) discharged in urine was evaluated.Results
Comparing the results between TCM and model control groups, scores of DAI and histological lesions decreased significantly (P = 0.000 < 0.01), ultrastructures of intestinal epithelial cells and tight junctions were more complete. The expression of occludin protein (P = 0.001 < 0.01) increased while the L/M value decreased significantly (P = 0.000 < 0.01) in TCM group. There was no statistical difference between the TCM and mesalazine groups in results of each item (P > 0.05).Conclusion
The decoction prepared with Yang-activating and stasis-eliminating TCM medicianls can restore intestinal mucosal epithelial cells and tight junctions the model rats with ulcerative colitis; it can reduce histological lesions and protect the permeability of intestinal mucosa barrier in the rats as well. 相似文献19.
葡聚糖微球经微导管栓塞术中应用参数的实验研究 总被引:4,自引:0,他引:4
目的:探讨葡聚糖微球经不同微导管栓塞治疗时的应用参数。减少血管栓塞术中微导管的阻塞。方法:(1)光镜及电镜下观测葡聚糖微球,并测定葡聚糖微球栓子悬液的悬浮稳定性。(2)用注射器人工推注和高压注射器自动注射,测试5种不同内径的微导管注射2种不同规格(50-150μm,100-300μm)各3种不同浓度(25mg/ml,50mg/ml,100mg/ml)的葡聚糖微球,记录注射时使用的压力和导管阻塞情况。(3)应用SPSS9.0软件对结果作统计学处理。结果:(1)葡聚糖微球原液加入等量的造影剂悬浮稳定性好;(2)不同规格的注射器注射相同的葡聚糖微球产生的推注压力不同;(3)经不同的微导管注射相同的葡聚糖微球时推注压力不同。用内径通过≤0.014英寸导丝的微导管注射葡聚糖微球将会堵管。结论:提倡介入栓塞术中使用5ml的注射器透视下推注栓子,避免使用内径配≤0。014英寸导丝的微导管注射葡聚糖微球。 相似文献
20.
目的:探讨复方丹参、右旋糖酐及尼莫通联合治疗外伤性脑梗死( PTCI)的临床效果。方法将72例颅脑损伤患者随机分为两组,各36例,均采用常规治疗和右旋糖酐及复方丹参联合治疗,观察组在此基础上加用尼莫通治疗,比较治疗后两组格拉斯哥昏迷评分( GCS)、神经功能缺损评分( NIHSS)及临床效果。结果两组治疗前GCS及NIHSS差异均无统计学意义( P >0.05);治疗后两组GCS及NIHSS均有所改善,观察组改善情况优于对照组( P <0.01);用药1个月后,观察组总有效率为97.2%,高于对照组的77.8%( P <0.05)。结论复方丹参、右旋糖酐及尼莫通联合治疗PTCI疗效显著,可有效改善患者神经功能及预后。 相似文献