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31.
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   
32.
神经内镜治疗脑室内病变   总被引:7,自引:2,他引:5  
目的探讨脑室内病变的神经内镜治疗。方法应用神经内镜对68例脑室内病变进行治疗,其中松果体区肿瘤16例,囊性颅咽管瘤15例,丘脑肿瘤14例,脑室内囊肿16例,侵及室管膜下的胼胝体肿瘤3例,侧脑室脉络丛乳头状瘤2例,侧脑室猪囊尾蚴病1例,侧脑室内分流管脱落1例。结果随访17~69个月,56例有效,12例死于肿瘤扩散。无严重并发症。结论对脑室内病变选择性应用神经内镜治疗安全、有效。  相似文献   
33.
神经导航内窥镜辅助下单鼻孔入路垂体腺瘤切除   总被引:1,自引:1,他引:0  
目的神经导航、内窥镜辅助下垂体腺瘤的经单鼻孔经蝶手术治疗。方法对6例经磁共振成像诊断垂体腺瘤的病人术前进行磁共振成像定位,将影像资料输入导航工作站,作术前手术计划。采用零度及45度镜经单鼻腔,在导航的动态指引下确认鞍底,于内窥镜下实施瘤实质切除。结果本组5例完全切除,1例因为瘤实质较韧而作大部分切除,术后病人的视力均得到了改善。导航预期误差1.48mm,实际误差1.8mm。结论神经导航引导下的经鼻蝶垂体腺瘤手术定位准确,内窥镜下操作对鼻腔的解剖结构影响小、组织损伤轻,病人恢复快。  相似文献   
34.
后腹腔镜手术切除肾上腺节细胞神经瘤疗效观察   总被引:6,自引:1,他引:5  
目的 :探讨后腹腔镜微创手术治疗肾上腺节细胞神经瘤的适应证和可行性。方法 :采用后腹腔镜手术治疗肾上腺节细胞神经瘤患者 5例 ,其中左侧肾上腺节细胞神经瘤 2例 ,右侧 3例。结果 :5例后腹腔镜手术全部获得成功 ,4例肾上腺肿瘤为单发 ,1例为多发 (4个肿瘤 ) ;肿瘤最大直径 2 .5~ 8.0 (4 .2± 1.8)cm ;手术时间35~ 10 5 (5 9± 2 7)min ,估计出血量 10~ 30 (19± 7)ml,术后镇痛剂吗啡用量 0~ 2 0 (8± 8)mg ,2例未用镇痛剂 ;排气、恢复进食时间 1~ 3(1.4± 0 .5 )d ;术后住院时间 4~ 7(5 .4± 1.5 )d。无围手术期并发症发生。结论 :后腹腔镜手术切除肾上腺节细胞神经瘤是安全可行的 ,能充分体现腹腔镜手术创伤小、恢复快的优点。肾上腺节细胞神经瘤是腹腔镜手术很好的适应证。  相似文献   
35.
36.
1976~1986年肿瘤科收治脑胶质瘤42例,10例复发,其中6例采用单纯放疗,用~60钴γ线。5例脑胶质瘤予肿瘤区局部照射,DT44~57Gy/6-7周,1例髓母细胞瘤予全脑、肿瘤区及全脊髓照射、脑中平面量DT38Gy/5周;肿瘤区51Gy/7周;脊髓18Gy/8周。结果:有效1例,显效2例,无效3例。本研究提示对于已不能釆用其他手段治疗的复发病人,放疗仍有一定效果。  相似文献   
37.
OBJECTIVE: To examine the distribution of rat facial motoneurons contributing different branches under normal situation and when nerve reinnervation occurred following facial nerve axotomy. METHODS: The normal distribution of motoneurons innervated both buccal and marginal mandibular branches and its reorganization after facial nerve reinnervation was observed using retrograde labeling with fluorescein. RESULTS: Under normal situation, the motoneurons contributing buccall and marginal mandibular branches were primarily distributed in the intermedial and lateral subnucleus in facial nucleus and almost completely overlapped. The two types labeled neurons organized closely, but there were no double-labeled neurons. Although the motoneurons contributing buccall and marginal mandibular branches were primarily overlapped 4 month post-anastomosis, the number of the labeled neurons obviously decreased and the organization got more scattered. There were 10% of buccall branches, 5% of marginal mandibular motoneurons in the dorsal subnuleus, 1% of buccall and 4% of marginal mandibular in dorsal ventral and medial subnucleus. The distribution pattern of the motoneurons 6 month post-anastomosis was similar to that of 4 month post-anastomosis, but the number of the labeled neurons increased, and there were 1%-2% double-labeled neurons. CONCLUSION: The distribution pattern of motoneurons innervated both buccal and marginal mandibular branches indicates that it should exist wide-spread communicating branches, and its reorganization after facial nerve reinnervation suggests that misdirected regeneration occurs among motoneurons innervating different branches.  相似文献   
38.
林岑  胡雁 《中国肿瘤》2007,16(8):606-609
全文以Walker和Avant概念分析格式介绍坚强(hardiness)的定义和特征,说明案例,分析前置因子和后果,列举坚强的评估方法和在不同人群中的运用.希望通过对坚强的全面分析加深医务人员对此概念的理解,从而有助于激发患者的坚强特质.  相似文献   
39.
Experimental study on the immunosuppressive effects of gui zhi tang   总被引:1,自引:0,他引:1  
X F Lu 《中西医结合杂志》1989,9(5):283-5, 262
In this paper the immunosuppressive effects of Gui Zhi Tang (a famous Chinese medicine) on the murine immune functions are reported. Varying dosages of Gui Zhi Tang administrated orally, i.p. and i.m. were able to inhibit the amounts of PFC, SRFC and the DTH response induced by BSA and the proliferation response of murine spleen cells to Con A and LPS. Further studies showed that Gui Zhi Tang had the inhibitory effect on Interleukin-2 production of murine spleen cells, which might be one of the mechanisms leading to the immunosuppressive effects of Gui Zhi Tang.  相似文献   
40.
切开复位内固定治疗Gartland Ⅲ型肱骨髁上骨折   总被引:2,自引:0,他引:2  
目的探讨切开复位内固定治疗Gartland Ⅲ型肱骨髁上骨折的疗效。方法1999年10月-2005年4月,对62例平均年龄7.5岁的患儿,应用切开复位克氏针固定治疗Gartland Ⅲ型肱骨髁上骨折。其中伸直尺偏型41例,伸直桡偏型18例,伸直中间型3例;无伴发血管、神经损伤和筋膜室间隔综合征。闭合性骨折47例,开放性骨折15例。结果术后56例获得随访,随访时间为6~15个月,平均11.5个月。所有骨折均获得愈合。根据Flynn标准进行疗效评价,其中优22例(占39.3%),良21例(37.5%),可9例(16.1%),差4例(7.1%)。伤后8h内手术的优良率为89.7%,伤后8h后手术的优良率为63.0%。直接手术治疗的优良率为90.1%,曾接受手法复位的优良率为67.7%。结论切开复位内固定治疗Gartland Ⅲ型肱骨髁上骨折可取得满意的疗效,是安全、有效的治疗方法。  相似文献   
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