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61.
62.
再生障碍性贫血患者血清sICAM—l和TGF—β1水平及其意义 总被引:1,自引:0,他引:1
目的 探讨再生障碍性贫血 (AA ,再障 )患者血清可溶性细胞间粘附分子 - 1(sICAM - 1)和转化生长因子β1(TGF - β1)水平及其意义 .方法 采用ELISA法检测再障 3 0例和骨髓增生异常综合征 (MDS) 15例 ,正常对照组 2 0例血清sICAM - 1和TGF - β1水平 .结果 慢性再障 (CAA)组sICAM - 1较正常组明显增高 (p <0 0 5 ) ,TGF - β1较正常组明显降低 (p <0 0 1) ;重型再障 (SAA)和MDS组sICAM - 1均较正常组显著增高 (p均 <0 0 1) ,TGF - β1均较正常组显著下降 (p均 <0 0 1) .SAA组sICAM - 1较CAA组显著增高 (p <0 0 5 ) ,MDS组与CAA组比较 ,sICAM - 1明显增高 (p <0 0 1) ,MDS组与SAA组比较 ,TGF - β1明显增高 (p <0 0 1) .动态观察 10例再障 ,随着病情的好转 ,sICAM - 1水平逐渐下降 ,TGF - β1水平趋于上升 ;当病情加重时 ,sICAM - 1上升 ,TGF - β1下降 .血清sICAM - 1和TGF - β1接近正常者疗效、预后好 .结论 高水平的sICAM - 1和低水平的TGF - β1可能参与再障造血干 /祖细胞衰竭的病理生理过程 ;动态检测sICAM - 1和TGF - β1水平 ,为再障患者监测病情、评价疗效、指导临床治疗及预后判断提供较为客观的指标 相似文献
63.
V Ghe?ie G Mo?a M A Dobre-Ghe?ie M Laky A Olinescu S Dima I Moraru J Sj?quist 《Molecular immunology》1986,23(4):377-384
The monovalent V-1 fragment of protein A (fSpA) with a mol. wt of 13,000 obtained from an u.v. mutant of Staphylococcus aureus Cowan I strain was proved to be able to modulate significantly some of the effector functions of IgG, such as complement fixation, catabolism, attachment to Fc receptors and antibody-dependent cell-mediated cytotoxicity. Moreover fSpA-like protein A obtained from the A676 strain is mitogenic and enhances NK activity of human peripheral lymphocytes. The efficiency of fSpA was found to be lower than that of protein A with regard to its ability to inhibit complement fixation, EA rosette formation and antibody-dependent cell-mediated cytotoxicity. Both protein A and fSpA had the same efficiency in activation of the complement system after reaction with human or guinea pig IgG, and in increasing the IgG catabolism. Unlike fSpA the monovalent B fragment of protein A (with mol. wt of 7000) was not able to inhibit EA rosette formation and antibody-dependent cell-mediated cytotoxicity. The results recommend fSpA, substituting for protein A, as a molecular probe for the investigation of IgG antibody and lymphocyte effector functions. 相似文献
64.
Jinyi Yuan Biwen Mo Zhuang Ma Yuan Lv Shih-Lung Cheng Yanping Yang Zhaohui Tong Renguang Wu Shenghua Sun Zhaolong Cao Jufang Wu Demei Zhu Liwen Chang Yingyuan Zhang 《Journal of microbiology, immunology, and infection》2019,52(1):35-44
Background/Purpose
Nemonoxacin is a novel nonfluorinated quinolone with excellent in vitro activity against most pathogens in community-acquired pneumonia (CAP), especially Gram-positive isolates. The purpose of this study was to assess the efficacy and safety of nemonoxacin compared with levofloxacin in patients with CAP.Methods
A phase 3, multicenter, randomized (2:1) controlled trial was conducted in adult CAP patients receiving nemonoxacin 500 mg or levofloxacin 500 mg orally once daily for 7–10 days. Clinical, microbiological response and adverse events were assessed. Non-inferiority was determined in terms of clinical cure rate of nemonoxacin compared with that of levofloxacin in a modified intention-to-treat (mITT) population. NCT registration number: NCT01529476.Results
A total of 527 patients were randomized and treated with nemonoxacin (n = 356) or levofloxacin (n = 171). The clinical cure rate at test-of-cure visit was 94.3% (300/318) for nemonoxacin and 93.5% (143/153) for levofloxacin in the mITT population [difference (95% CI), 0.9% (?3.8%, 5.5%)]. The microbiological success rate was 92.1% (105/114) for nemonoxacin and 91.7% (55/60) for levofloxacin in the bacteriological mITT population [difference (95% CI), 0.4% (?8.1%, 9.0%)]. The incidence of adverse events (AEs) was comparable between nemonoxacin (33.1%, 118/356) and levofloxacin (33.3%, 57/171) (P > 0.05).Conclusion
Nemonoxacin 500 mg once daily for 7–10 days is as effective and safe as levofloxacin for treating adult CAP patients in terms of clinical cure rates, microbiological success rates, and safety profile.ClinicalTrials.gov identifier: NCT01529476. 相似文献65.
Myung Ha Yoon Kyung Deok Park Hyung Gon Lee Woong Mo Kim Tae Hoon An Yeo Ok Kim Lan Ji Huang Cui Jin Hua 《Journal of Korean medical science》2008,23(6):1033-1038
The possible characteristics of spinal interaction between sildenafil (phosphodiesterase 5 inhibitor) and morphine on formalin-induced nociception in rats was examined. Then the role of the opioid receptor in the effect of sildenafil was further investigated. Catheters were inserted into the intrathecal space of male Sprague-Dawley rats. For induction of pain, 50 µL of 5% formalin solution was applied to the hind-paw. Isobolographic analysis was used for the evaluation of drug interaction between sildenafil and morphine. Furthermore, naloxone was intrathecally given to verify the involvement of the opioid receptor in the antinociception of sildenafil. Both sildenafil and morphine produced an antinociceptive effect during phase 1 and phase 2 in the formalin test. The isobolographic analysis revealed an additive interaction after intrathecal delivery of the sildenafil-morphine mixture in both phases. Intrathecal naloxone reversed the antinociception of sildenafil in both phases. These results suggest that sildenafil, morphine, and the mixture of the two drugs are effective against acute pain and facilitated pain state at the spinal level. Thus, the spinal combination of sildenafil with morphine may be useful in the management of the same state. Furthermore, the opioid receptor is contributable to the antinocieptive mechanism of sildenafil at the spinal level. 相似文献
66.
Anticocaine catalytic antibodies 总被引:5,自引:0,他引:5
Cocaine mediates its reinforcing and toxic actions through a "loss of function" effect at multiple receptors. The difficulties inherent in blocking a pleiotropic blocker pose a great obstacle for the classical receptor-antagonist approach and have contributed to the failure (to date) to devise specific treatments for cocaine overdose and addiction. As an alternative, we have embarked on an investigation of catalytic antibodies, a programmable class of artificial enzyme, as "peripheral blockers" -- agents designed to bind and degrade cocaine in the circulation before it partitions into the central nervous system to exert reinforcing or toxic effects. We synthesized transition-state analogs of cocaine's hydrolysis at its benzoyl ester, immunized mice, prepared hybridomas and developed the first anticocaine catalytic antibodies with the capacity to degrade cocaine to nonreinforcing, nontoxic products. We subsequently identified several families of anticocaine catalytic antibodies and found that the most potent antibody possessed sufficient activity to block cocaine-induced reinforcement, organ dysfunction and sudden death in rodent models of addiction, toxicity and overdose, respectively. With the potential to promote cessation of use, prolong abstinence and provide a treatment for acute overdose, the artificial enzyme approach comprehensively responds to the problem of cocaine. 相似文献
67.
Electrospun P(LLA-CL) nanofiber: a biomimetic extracellular matrix for smooth muscle cell and endothelial cell proliferation 总被引:26,自引:0,他引:26
Poly(L-lactide-co-epsilon-caprolactone) [P(LLA-CL)] with L-lactide to epsilon-caprolactone ratio of 75 to 25 has been electrospun into nanofibers. The relationship between electrospinning parameters and fiber diameter has been investigated. The fiber diameter decreased with decreasing polymer concentration and with increasing electrospinning voltage. The X-ray diffractometer and differential scanning colorimeter results suggested that the electrospun nanofibers developed highly oriented structure in CL-unit sequences during the electrospinning process. The biocompatibility of the nanofiber scaffold has been investigated by culturing cells on the nanofiber scaffold. Both smooth muscle cell and endothelial cell adhered and proliferated well on the P(LLA-CL) nanofiber scaffolds. 相似文献
68.
应用原位杂交和免疫组化PAP法双标记技术,结合病人乙型肝炎(乙肝)病毒血清学标志物检测结果,研究了31例慢性乙肝病人肝穿刺组织中乙型肝炎病毒DNA(HBV DNA)和HBsAg的分布及意义。结果显示,肝组织内检出HBV DNA 23例,HBsAg 26例,二者同时检出者21例。从同组病人肝组织内HBV DNA和HBsAg双标检测结果与其乙肝病毒血清学标志物检测结果的比较来看,肝组织内HBV DNA和HBsAg同时阳性很可能表明HBV正处于复制及表达的活动状态。 相似文献
69.
应用免疫细胞化学(ICC)和放射免疫分析(RIA)方法观察了大鼠4、25Gy~(60)Coγ射线照射后24,48和,72h空肠亮脑啡肽(L-ENK)样免疫反应性神经的分布和L-ENK含量的变化。结果:4Gy照射后24h以及25Gy照射后24,48和72h光镜下见空肠L-ENK样免疫反应性神经的分布密度稍有增加,4Gy照射后24h以及25Gy照射后24,48和72h空肠L-ENK含量分别为29.81±0.84pg/mg,34.96±4.38pg/mg,40.71±3.62pg/mg和38.93±2.31pg/mg,与正常对照组(18.26±1.95pg/mg)相比明显升高(P<9.01)。 相似文献
70.
可切削渗透陶瓷玻璃料对不同堆积密度氧化铝基体的渗透 总被引:1,自引:0,他引:1
探讨了可切削渗透陶瓷 (Infiltration of Machinable- infiltrated- ceramic,MIC)渗透玻璃在不同堆积密度氧化铝基体中的渗透情况及渗透后复合体的颜色表达。在 110 0℃保温 2 h,将玻璃渗透到不同堆积密度的氧化铝基体中 ,分别测得其渗透深度和颜色参数。扫描电镜观察玻璃—氧化铝复合体断面。玻璃渗透深度的平方与氧化铝堆积密度有直线负相关关系 ,最小渗透深度为 3.0 92 m m。复合体的颜色系数与氧化铝堆积密度无相关性。渗透复合体在断裂过程中可见 :裂纹偏转、晶体拔出和穿晶断裂。本实验证实 MIC渗透玻璃的渗透性能达到临床要求。渗透后的复合体颜色稳定 ,强度可靠 相似文献