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101.
Zhong Rui-kun钟瑞琨 Dong Yong-he董永和and Lu Dao-pei陆道培Institute of Hematology Beijing Medical University Beijing 《中华医学杂志(英文版)》1989,102(7):537-544
In order to understand the mechanism of immunosuppression caused by infusion of placental gamma globulin (PGG) in patients with renal allografts, rheumatoid arthritis, and graft – versus –host disease (GCHD) following bone marrow transplantation (BMT) ,we have examined the effect of PGG in vitro and in a model of the xenogeneic , local graft –ver- sus – host reaction (LGVHR) .PGG inhibited lymphocyte proliferation in mixed lymphocyte cultures (MLC) (P<0.005) and depressed interleukin -2 (IL-2) levels in such cultures at 72 hours (P<0.01) . In contrast phytohemagglutinin (PHA) –and pokeweed mitogen (PWM) –induced T and B lymphocyte blastogenesis was not affected by such PGG treatment .PGG treatment .PGG neither decreased the [3H] TdR pulse incorporation in unstimulated lymphocytes nor affected cell viability .Cell cycle analysis by flow cytometry showed that PGG reduced the percentage of cells in S and G2, M phases during the MLC, but did not alter cell cycling during PWM-stimulated proliferation .
An immunosuppressive effect of PGG on the LGCHR was tested in a model of intracutaneous transplantation of PGG –treat human lymphocytes into cyclophosphamide – immunosuppressed rats. Lymphoprep – separated human tonsillar lymphocytes were incubated with RPMI-1640 buffer containing:(1)PGG,4mg/ml,(2) human plasma albumin,4mg/ml,(3)mitomycin-C,25ug/ml, or (4) no additive. Cell of each preparation (3x107cells in 0.1ml) were injected intracutaneously into cyclophosphamide-treated male rats at separate abdominal locations. A fifth site received only the buffer solution. Five days after injection of cells ,each rat received [125 I]IUdR (10uCi) intraperitoneally and was killed after 5 hours. For each site of injection, the diameters of induration were measured and 125 I was counted . There was no difference between buffer – treated and a ibumin – treated groups either in the diameter of the area of induration (t=0.66;P>0.5)or in radioactive counts(t=0.22;P>0.05).In the PGG –treated group, the induration and radioactivity measurements were significantly less than in control groups (t=3.72 and P<0.1;t=2.62 and P<0.02,respectively ) Cytophilic antibodies in PGG were thought to inhibit an early phase of T cell activation, and not to be cytotoxicity .In the LGVHR, the immune response might be abrogated either by immuno- regulatory suppression of T cell function or by toxicity to the infused lymphoid cells. For some clinical purposes, immuno- modulating, human antibodies might be preferred to murine, monoclonal antibodies. 相似文献
102.
100例2型糖尿病患者交感神经皮肤反应研究 总被引:1,自引:0,他引:1
目的探讨交感神经皮肤反应(SSR)检测在评价2型糖尿病(T2DM)自主神经损害中的价值.方法对100例T2DM患者进行SSR检测,30例健康志愿者作为对照.结果2组SSR的起始潜伏期、N波潜伏期、波幅、面积比较差异有显著性意义(P<0.05),P波潜伏期差异无显著性意义(P>0.05).T2DM组72例(72%)患者至少有一肢SSR异常.血糖控制满意组和血糖控制不良组比较,起始和N波潜伏期差异有统计学意义(P<0.05),波幅和面积无显著性意义(P>0.05).T2DM组病程<5年与病程≥5年比较,潜伏期、波幅、面积差异均无统计学意义(P>0.05).结论SSR可作为评价T2DM自主神经损害的客观电生理指标;T2DM患者SSR与血糖控制水平相关,与病程无关. 相似文献
103.
In order to investigate the analgesic effect of needling at “Sitian” points for the nerve root-involved cervical spondylopathy, 68 cases of the nerve root-involved cervical spondylopathy were randomly divided into a treatment group of 46 cases treated by needling at "Sitian" points, and a control group of 22 cases treated by needling at cervical Jiaji points. After 2 therapeutic courses, the therapeutic effects were evaluated by using the visual analogue scale (VAS) and the semeiographic format. The results showed that the markedly effective rate was 78.3% and 54.5%, respectively in the treatment group and the control group, and the difference between the two groups was of significance (P〈0.05). It can be concluded that needling at “Sitian” points can bring about a better therapeutic effect on the improvement of clinical symptoms, ohvsical signs and pain than that of the needling at the cervical Jiaii points. 相似文献
104.
105.
关节镜辅助下的同种异体半月板移植(附4例术后20个月以上随访报告) 总被引:5,自引:0,他引:5
目的:介绍同种异体半月板移植并总结4例关节镜辅助下的同种异体半月板移植的初步临床效果。材料和方法:2005年6月~7月,4例半月板切除术后的患者接受关节镜辅助的同种异体半月板移植手术,其中男性3例、女性1例,平均年龄30.78±7.71岁(21.5~38.5岁)。3例内侧半月板移植,1例外侧半月板移植。随访采用症状询问,体征检查,IKDC、Lysholm和Tegner评分及KT2000测量关节稳定性的方法。4例患者均每半年进行一次X线片及MRI检查,分别观察膝关节的关节间隙改变及移植半月板状态。对所得结果,因病例只有4例,故只进行数据描述,不进行统计学分析。结果:对4例患者均进行了平均21.80±0.81(20~22)个月的随访。所有患者随访时关节活动度均正常,均无明显的膝关节疼痛和肿胀,原来长时间活动后被切除半月板的间室不适完全消失。患者可以胜任日常活动和体育锻炼,无并发症出现。IKDC、Lysholm、Tegner评分均较术前明显提高。KT2000测量发现术后膝关节的稳定性有所改善。X线片检查提示术后患者关节间隙无明显变化。每半年一次的MRI检查提示移植半月板术后1年时替代存活已经很好。结论:关节镜辅助下的同种异体半月板移植安全可行,半月板移植可缓解半月板切除后出现的关节疼痛、肿胀等症状,促进关节功能恢复并使膝关节的稳定性有所改善。 相似文献
106.
107.
目的 应用meta分析正确评价学龄儿童单纯性肥胖对智商的影响。方法 对检索到的符合标准的11篇相关文献进行meta分析,选择随机效应模型进行统计处理。结果 单纯性肥胖组与对照组儿童智商比较,平均较应尺度为-0.3385,平均效应尺度的95%可信区间为-0.8036~0.1266。结论 单纯性肥胖对智商影响的meta分析结果无统计学意义。 相似文献
108.
目的探讨自体腓骨移植在桡腕关节重建术中的应用价值.方法应用带关节囊腓骨近端移植修复桡骨远端骨巨细胞瘤因瘤段切除后的骨缺损,游离移植4例,带血管蒂移植3例.结果所有被修复骨缺损均良好愈合,腕关节功能与外观令人满意.结论自体腓骨移植是修复桡骨远端缺损的理想供本,操作安全、有效、合并症少. 相似文献
109.
使用N-甲基吗啉-N-氧化物的水合物(NMMO·H2O)作为再生丝素的溶剂.可以得到w=0.10~0.25的再生丝素/NMMO·H2O溶液.研究了再生丝素/NMMO·H2O溶液流变性能,讨论了剪切速率、温度和溶液中的再生丝素的含量对再生丝素/NMMO·H2O溶液流变性能的影响. 相似文献
110.
Experimental Study on Allogenic Decalcified Bone Matrix as Carrier for Bone Tissue Engineering 总被引:11,自引:0,他引:11
The biocompatibility and osteogenic activity of allogenic decalcified bone matrix (DBM) used as a carrier for bone tissue engineering were studied. Following the method described by Urist, allogenic DBM was made. In vitro, DBM and bone marrow stromal cell (BMSC) from rab-bits were co-cultured for 3-7 days and subjected to HE staining, and a series of histomorphological observations were performed under phase-contrast microscopy and scanning electron microscopy (SEM). In vivo the mixture of DBM/BMSC co-cultured for 3 days was planted into one side of muscules sacrospinalis of rabbits, and the DBM without BMSC was planted into other side as con-trol. Specimens were collected at postoperative week 1, 2 and 4, and subjected to HE staining, and observed under SEM. The results showed during culture in vitro, the BMSCs adherent to the wall of DBM grew, proliferated and had secretive activity. The in vivo experiment revealed that BMSCs and undifferentiated mesenchymal cells in the perivascular region invaded gradually and proliferated together in DBM/BMSC group, and colony-forming units of chondrocytes were found. Osteoblasts,trabecular bone and medullary cavity appeared. The inflammatory reaction around muscles almost disappeared at the second weeks. In pure DBM group, the similar changes appeared from the sur-face of the DBM to center, and the volume of total regenerate bones was less than the DBM/BMSC group at the same time. The results indicated that the mixture of DBM and BMSC had good bio-compatibility and ectopic induced osteogentic activty. 相似文献