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31.
32.
竹荪深层发酵菌丝体对小鼠免疫功能的影响及其抗肿瘤作用 总被引:12,自引:0,他引:12
过对食药用真菌──竹荪深层发酵菌丝体提取液对小鼠免疫功能及S-180肿瘤细胞的作用观察,表明其发酵菌丝体可明显提高小鼠腹腔巨噬细胞的吞噬功能(P<0.01),并显著增加免疫器官的重量(P<0.05);对小鼠S-180肿瘤的抑瘤率为40.63%。 相似文献
33.
本文对以重组淋球菌IgA蛋白酶为抗原制备的7株特异性McAb的特性进行了初步研究。结果有5株(1C8、1E5、1F11、1G3和2E6)能中和淋球菌IgA蛋白酶活性。经相加试验初步证明,其中1F11、2G3与其它3株McAb的作用位点不同。因此,淋球菌IgA蛋白酶至少存在3个中和表位。 相似文献
34.
气管与主支气管肿瘤的影像诊断(附32例报告) 总被引:5,自引:1,他引:4
作者对32例经病理证实的气管与主支气管良、恶性肿瘤的影像学表现进行分析,归纳为3型:腔内型、壁增厚型和腔内外型。后2种类型提示恶性,而无蒂的腔内型表现者不能鉴别良,恶性。作者还评价了常规体层、CT及MRI诊断气管与主支气管肿瘤的优、缺点,讨论了影像诊断的作用。 相似文献
35.
腰椎峡部裂的CT诊断 总被引:12,自引:2,他引:10
目的:回顾性分析腰椎峡部裂的CT表现并讨论其诊断与鉴别诊断,材料与方法,23例患先行腰椎侧位扫描定位图像,采用与椎间盘平行的角度,自病变脊椎的上一椎体下缘边续发描至于下椎体上缘,层厚4或5mm必要时在峡部行2mm,层厚扫描,结果;23例中,累及双侧21例,单侧2例,发生在L516例,L47例,CT表现为同一脊椎关节突间的低密度裂隙,出瑞椎弓根下缘平面,走行不规则,裂隙可宽可窄,表面不光滑。 相似文献
36.
Dolastatin 10, a cytostatic peptide containing several unique amino acid subunits, was isolated from the marine shell-less mollusk Dolabella auricularia (Pettit GR, Kamano Y, Herald CL, Tuinman AA, Boettner FE, Kizu H, Schmidt JM, Baczynskyj L, Tomer KB and Bontems RJ, J Am Chem Soc 109: 6883-6885, 1987). Since our preliminary studies demonstrated that dolastatin 10 inhibited tubulin polymerization and the binding of radiolabeled vinblastine to tubulin, an initial characterization of the properties of dolastatin 10 included a comparison to other antimitotic drugs interfering with vinca alkaloid binding to tubulin (vinblastine, maytansine, rhizoxin, and phomopsin A). Dolastatin 10 inhibited the growth of L1210 murine leukemia cells in culture, with a concordant rise in the mitotic index, and its IC50 value for cell growth was 0.5 nM. Comparable values for the other drugs were 0.5 nM for maytansine, 1 nM for rhizoxin, 20 nM for vinblastine, and 7 microM for phomopsin A. IC50 values were also obtained for the polymerization of purified tubulin in glutamate: 1.2 microM for dolastatin 10, 1.4 microM for phomopsin A, 1.5 microM for vinblastine, 3.5 microM for maytansine, and 6.8 microM for rhizoxin. Dolastatin 10 and vinblastine were comparable in their effects on microtubule assembly dependent on microtubule-associated proteins. Preliminary studies indicated that dolastatin 10, like vinblastine, causes formation of a cold-stable tubulin aggregate at higher drug concentrations. We confirmed that rhizoxin, phomopsin A, and maytansine also inhibit the binding of radiolabeled vinblastine and vincristine to tubulin. Dolastatin 10 and phomopsin A were the strongest inhibitors of these reactions, and rhizoxin the weakest. Dolastatin 10, phomopsin A, maytansine, vinblastine, and rhizoxin all inhibited tubulin-dependent GTP hydrolysis. The greatest inhibition of hydrolysis was observed with dolastatin 10 and phomopsin A, and the least inhibition with rhizoxin. 相似文献
37.
Effect of dialysis flux and membrane material on dyslipidaemia and inflammation in haemodialysis patients. 总被引:4,自引:0,他引:4
Christoph Wanner Udo Bahner Renate Mattern Dietmar Lang Jutta Passlick-Deetjen 《Nephrology, dialysis, transplantation》2004,19(10):2570-2575
BACKGROUND: Dyslipidaemia, inflammation and oxidative stress are prominent risk factors that potentially cause vascular disease in haemodialysis patients. Dialysis modalities affect uraemic dyslipidaemia, possibly by modifying oxidative stress, but the effects of dialyser flux and membrane material on atherogenic remnant particles and oxidized low-density lipoproteins (LDL) are unknown. METHODS: We performed a randomized crossover study in 36 patients on haemodialysis to analyse the effect of dialyser flux and membrane material on plasma lipids, apolipoproteins and markers of inflammation and oxidative stress. Stable patients on low-flux dialysis with polysulphone for >/=6 weeks were assigned to high-flux polysulphone or high-flux modified cellulose with similar dialyser surface area and permeability characteristics and crossed over twice every 6 weeks. RESULTS: Thirty patients completed the study per protocol. Treatments with high-flux polysulphone and modified cellulose lowered serum triglyceride (by 20% and 10%, respectively; P<0.05) and remnant-like particle cholesterol by 32% (P<0.001) and 11% (NS) after the first 6 weeks of treatment. Oxidized LDL decreased significantly with high-flux polysulphone, but not with modified cellulose. Apolipoproteins CII and CIII were reduced, whereas the ratio CII/CIII was increased (all P<0.05). Acute-phase proteins and LDL and high-density lipoprotein cholesterol remained unaffected. CONCLUSIONS: This randomized crossover study demonstrates a potent effect of high-flux haemodialysis on uraemic dyslipidaemia. Polysulphone membrane material showed superiority on oxidatively modified LDL, an indicator of oxidative stress in haemodialysis patients. 相似文献
38.
目的 研究在IL 2和IL 4作用下 ,趋化性细胞因子受体CCR3在人生发中心 (germinalcenter,GC)B细胞上的表达及其功能特性。方法 采用流式细胞术检测人GCB细胞上CCR3表达和在CCR3配体eotaxin作用下B细胞的凋亡 ,实时定量RT PCR和Northernblot法检测GCB细胞内CCR3mRNA的表达 ,淋巴细胞趋化和黏附试验检测B细胞的趋化和黏附能力。结果 人GCB细胞极低表达趋化性细胞因子受体CCR3,经IL 2和IL 4作用后 ,GCB细胞高表达CCR3,但此时CCR3不能在其配体作用下诱导GCB细胞的趋化和黏附功能 ,而是诱导GCB细胞凋亡。结论 IL 2和IL 4联合诱导人GCB细胞CCR3表达 ,CCR3可能具有死亡受体的功能。 相似文献
39.
Cardiac insufficiency, coronary heart disease, and arrhythmia are not only more frequent in elderly patients, they are very often combined. By reason of cardiac morbidity and general morbidity as well as changed physiological and pathophysiological conditions, diagnosis of cardiac disease in elderly patients is more difficult. These conditions also apply to modifications in the therapy of cardiac diseases in advanced age. Especially pharmacodynamic and pharmacokinetic effects in advanced age combined with multimorbidity also account for the risk of interactions because of the simultaneous application of different pharmacological groups. 相似文献
40.
Clemens Aigner Peter Jaksch Samy Mazhar Kriztina Czebe Gabriel Marta Sharokh Taghavi Georg Lang Walter Klepetko 《European journal of cardio-thoracic surgery》2004,25(2):184-187
OBJECTIVES: The use of OKT3 for treatment of advanced high-grade acute rejection episodes eventually can result in cytokine release and consecutive pulmonary edema. Temporary extracorporeal membrane oxygenation (ECMO) bridging can be used to overcome this crucial period before the beneficial effects of OKT3 can be observed. METHODS: We summarize our experience with three patients, who underwent lung transplantation and presented with severe acute rejection episodes. OKT3 had to be initiated due to insufficient response to standard rejection therapy with corticosteroids. Upon initiation of OKT3 treatment, a massive life-threatening deterioration of lung function in spite of heavily invasive respirator treatment was seen and temporary ECMO support was imperative to support graft function. Results of this treatment were retrospectively reviewed. RESULTS: In all cases femoro-femoral veno-arterial ECMO was used for support of the impaired graft and after a period of 4-5 days led to a massive improvement of graft function. In the further course two patients could be discharged from hospital and are still alive 30 and 36 months, respectively, after the described incident. One patient died 4 months later due to liver failure. CONCLUSIONS: We conclude that the use of ECMO support in patients experiencing significant side effects from OKT3 therapy is a useful and effective therapeutic tool to overcome the initial critical period until the lung has sufficiently recovered. 相似文献