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11.
目的:探讨P物质抑制剂-辣椒素及bFGF抗体单独或联合使用对体外培养的人体增生性瘢痕成纤维细胞增殖的影响。方法:体外培养12例增生性瘢痕组织的成纤维细胞,分别加入不同浓度的辣椒素或/和bFGF抗体,培养24h后观察细胞形态学变化,并用MTT法检测细胞增殖抑制率。结果:所有不同浓度的辣椒素(2.5,5,20,40,60,80mg/L)均能使细胞皱缩、坏死,抑制细胞增殖,其抑制作用随剂量增大而增加。中高浓度bFGF抗体(40,80mg/L)也可促使细胞皱缩、坏死,抑制细胞增殖,其抑制作用也随剂量增大而增加。辣椒素与bFGF抗体联合应用对成纤维细胞抑制作用较单独使用效果更显著(P﹤0.05)。结论:辣椒素及bFGF抗体可抑制增生性瘢痕成纤维细胞增殖,其抑制作用随浓度增加而增加,两者联合使用有协调作用,本研究结果可能在增生性瘢痕的治疗提供新的思路和手段。  相似文献   
12.
目的:观察体外联合培养的成纤维细胞对平滑肌细胞形态和增殖的影响,为研究成纤维细胞和平滑肌细胞生物学特性和相互关系以及体外构建含此两种细胞的组织工程皮肤提供理论和实践基础。方法:在体外分别分离培养成纤维细胞和平滑肌细胞并常规传代培养。模拟组织工程皮肤的结构及成纤维细胞和平滑肌细胞间的相互影响途径,按照不同比例(平滑肌细胞:成纤维细胞=1:1,1:2,1:3)建立以胶原凝胶为基质的成纤维细胞与平滑肌细胞联合培养模型。应用荧光标记、组织学观察和MTT法对平滑肌细胞的形态和代谢进行研究。结果:联合培养模型法可以有效地建立起成纤维细胞和平滑肌细胞的相互影响模式。1:1组的成纤维细胞对联合培养的平滑肌细胞增殖有促进作用,1:3组的促增殖作用则不明显。结论:1:1联合培养的成纤维细胞对平滑肌细胞增殖有促进作用,对它们体外培养和扩增以及相互关系的研究对阐明这两种细胞组合作为真皮替代物种子细胞具有重要的意义。  相似文献   
13.
14.
Recently many mammaplasty techniques have been presented with special attention paid to the resulting scar's size and its position. The surgeon should try to hid the scar, and if the inverted T incision is used, its horizontal branch should be as short as possible and kept in the breast area. Neverthelss, excessive concern about the final scar size should not interfere with the final results of the mammaplasty as far as shape, volume and lasting results are concerned. The author presents his experience in mammaplasty with respect to the volume, the shape, and the scar size interrelationships.  相似文献   
15.
对石家市结核病的流行情况进行了随机抽样调查,共抽取24个调查点(市区8个、郊县16个)35745人。调查结果:平均患病率及菌阳患病率为0.63%和1.27%,其中郊县与市区分别为0.67%和0.54%及1.60‰和0.42‰(Ρ<0.01);15岁以下儿童有卡痕者,其结素反应阳性率年龄曲线,在7岁和12岁表现为低谷;1~3岁卡痕检出率,市区与郊县分别为90.5%与35.4%(Ρ<0.01)。通过本调查表明,我市结核病患病率高于全国1985年调查的平均数值。  相似文献   
16.
The expression of mRNA encoding the inflammatory cytokines interleukin-1α (IL-1α), interleukin-1β (IL-1β), interleukin-6 (IL-6), interleukin-8 (IL-8) and tumor necrosis factor α (TNF-α) have been examined in radicular cysts by in situ hybridization. Furthermore, the biological activity of the contents of radicular cysts (RCC) has been assayed by adding extracts of RCC to cultured human gingival fibroblasts (HGFs) and analyzing the culture medium for the release of inflammatory cytokines. In the epithelial layer, keratinocytes expressed all cytokine mRNAs examined at various levels. Basal layer cells expressed mRNA for each cytokine. In the subepithelial granulation tissue of the cysts, fibroblasts and macrophages expressed mRNA for IL-6, IL-8, IL-1β and TNF-α mRNA at varying levels; especially clear expression of TNF-α and IL-1β mRNA was detected on macrophages. The infiltrating lymphoid cells, largely composed of T cells and plasma cells, expressed these cytokine mRNAs, especially those encoding IL-6 and IL-8, at various levels. In vitro analysis indicated dose-dependent release of both IL-6 and IL-8 by HGFs in response to RCC. After heating to 100°C for 10 min, RCC almost completely failed to stimulate IL-6 release from HGFs. Furthermore, anti-IL-1β antibody (neutralization test) did not prevent the stimulation of IL-6 release by RCC. Significant amounts of IL-6 and IL-8 were detected in RCC in two cases, and a trace amount of IL-1β was detected in one case. This study demonstrated the wide expression of mRNA encoding inflammatory cytokines in radicular cyst tissues, and RCC itself was capable of stimulating 1L-6 and 1L-8 production from HGFs.  相似文献   
17.
The effect of Cyclosporin A (CsA) on prostaglandin E2 (PGE2) production in human gingival fibroblasts challenged with tumor necrosis factor alpha (TNF-α) was studied. TNF-α (1-100 ng/ml) dose-dependently stimulated PGE2; formation in 24 h cultures. CsA (1-100 ng/ml) did not induce PGE2; formation itself but potentiated TNF-α induced PGE; formation in gingival fibroblasts in a manner dependent on the concentrations of both CsA and TNF-α. TNF-α (10 ng/ml) stimulated the release of [3H]-arachidonic acid (A.A) from prelabelled fibroblasts that was potentiated by CsA (100 ng/ml). Addition of exogenous unlabelled AA (5-20 μM/ml) to the cells resulted in enhanced PGE2: formation that was not potentiated by CsA (100 ng/mi). Furthermore. CsA (100 ng/ml) did not further increase the level of cyclooxygenase-2 mRNA induced by TNF-α (10 ng/ml). although PGE2 formation was enhanced. The results indicate that CsA and TNF-α act in concert on PGE2 formation in gingival fibroblasts. which may be of importance in the pathogenesis of gingival overgrowth induced by the drug.  相似文献   
18.
Congenital “healed” cleft lip (CHCL) is an unusual anomaly including a paramedian “scar” of the upper lip, which appears as if a typical cleft lip has been corrected in utero. The CHCL is frequently associated with an ipsilateral notch in the vermilion, and “collapsed” nostril. Twenty-five CHCL cases are presented, eighteen of which were an isolated malformation found among the 3,950,715 births examined in two similar birth defect registries: ECEMC in Spain and ECLAMC in Latin America. Like open cleft lip, of which it seems to be a variant, CHCL is most frequently seen among males (14/18 isolated cases), it preferentially affects the left side (10/18 cases), and it segregated together with cleft lip in one family. The five CHCL cases with other congenital anomalies included: two cases with hydrocephalus, two VACTERL associations, and one atypical oblique facial cleft infant with single umbilical artery. CHCL may result from a defective fusion of the frontonasal and maxillary processes (before week 7 of embryonic life), or from a spontaneously repaired open cleft lip, later on. In either way, these cases heal with a visible scar, and the pre-occurrence of CHCL in two families suggests a familial predisposition to this phenomenon. © 1995 Wiley-Liss, Inc.  相似文献   
19.
应用全厚皮片移植修复治疗183例颈部烧伤后瘢痕挛缩畸形患者,术后经3~5年随访观察效果确切.并对全厚皮片术后易发生收缩的问题,进行讨论.  相似文献   
20.
MRI诊断腰椎间盘术后粘连和突出复发   总被引:2,自引:0,他引:2  
失败的下腰椎手术是个复杂的问题,由于其症状和体征不典型,单靠临床检查很难明确诊断,而脊髓造影和常规CT等检查也很难区别突出复发和硬膜外粘连。本文分析了32例再手术患者MRI图象,并与第二次手术所见对比,发现27例MRI诊断准确,3例假阳性,2例因信号缺失不能明确诊断。  相似文献   
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