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21.
Lei Wang Moyi Sun Yuegui Jiang Lianjia Yang Delin Lei Chao Lu Yinghua Zhao Pu Zhang Yaowu Yang Jianhu Li 《Journal of oral and maxillofacial surgery》2006,64(4):636-641
PURPOSE: Perineural invasion is a frequent occurrence in salivary adenoid cystic carcinoma (ACC) and may prevent complete surgical resection. Studies have indicated that nerve growth factor (NGF) and its high-affinity receptor tyrosine kinase A (TrkA) may play a role in perineural invasion in several malignancies in which perineural invasion is observed. The present study was conducted to investigate the expression of NGF and TrkA in salivary ACC and to examine the effects of NGF on adhesion, migration and invasion capacities of a salivary ACC cell line (SACC-83) in vitro. PATIENTS AND METHODS: Expression of NGF and TrkA was explored using immunohistochemistry in paraffin-embedded tissues of 32 cases of salivary ACC. The effects of NGF on in vitro adhesion, migration, and invasion capacities of the SACC-83 cell line were examined using an MTT assay and a modified Boyden chamber assay respectively. RESULTS: In ACC specimens, 31 (96.9%) and 32 (100%) tumors showed immunoreactivity for NGF and TrkA respectively. Significant correlations were found between NGF/TrkA expression levels and perineural invasion (P < .05). In cell adhesion assay, the percent adherences of SACC-83 cells co-cultured with 25 ng/ml NGF at 1.5 hours and 5, 25 ng/ml NGF at 6 hours were significantly higher than that co-cultured with 0 ng/ml NGF (P < .05). However, high concentration of NGF (500 ng/ml) resulted in a significant inhibition of invasion (P < .05). CONCLUSION: Overexpression of NGF and TrkA in human salivary ACC tissues may constitute a reason for perineural invasion in salivary ACC. 相似文献
22.
组织扩张术皮肤胶原的代谢改变 总被引:4,自引:0,他引:4
目的:研究常规扩张(ITE)和持续快速扩张(CTE)对皮肤胶原代谢的影响。方法用白色小家猪制作组织扩张术动物模型,用Gordeladze法测定血清和扩张组织的羟脯氨酸(HP)含量,藻酸盐印模材膜片法测量标记区面积;光镜测量真皮厚度。结果:ITE组血清HP含量升高,0.8倍,CTE组升高1.2倍,ITE和CTE组皮肤含量与正常皮肤相同,组织中HP总量均明显升高,持续扩张皮瓣组(CTEF)术后4wk皮 相似文献
23.
Five commercially available nitropolyclyclic aromatic hydrocarbons (nitro-PAH), namely, 4-nitrobiphenyl, 2-nitrofluorene, 9-nitroanthracene, 1-nitropyrene, and 2,7-dinitrofluorene, were exposed under restricted sunlight in the open air. The direct-acting mutagenicities of the samples after an exposure of 45 days were measured in order to compare them with those of the original samples in the Ames Salmonella typhimurium bioassay. It was found that the mutagenicities of some nitro-PAH do not change significantly while the mutagenicities of others increase or decrease after exposure. A preliminary study of nitro-PAH reaction products after exposure using GC, GC/MS, and FT-IR is also reported. 相似文献
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Viral markers were studied in 79 cases of viral hepatitis with hepatic failure. The results were shown as follows: 8 cases were positive for anti-HAV IgM (10.12%); 76 cases positive for HBsAg or anti-HBc IgM (96.20%) and 41 cases positive for anti-HCV antibodies (51.89%). Among those with anti-HCV positive, 35 cases were co-infected with HBV, 5 cases with HAV and/or HCV, only one was infected with HCV alone 2 cases were HD-Ag positive (2.52%) and one not identified (1.27%). With the reference of clinical findings, patients co-infected with HBV/HCV or anti-HBc IgM positive were more critical and usually entail higher mortality. In cases with HCV co-infections, the positive HBV replication markers seems to be reduced. Hepatic failure without HBV replicative markers had a high rate of hepatic coma as well as poor outcome. 相似文献
27.
In this immunohistochemical study, the authors detected the expression of c-myc in keratinocytes (ECK) from 30 psoriatics before and after Qingdai Compound Capsule (QDCC) treatment and 12 normal subjects for control. The results showed that the ECK of patients before treatment was significantly higher than that in the normal control group, and its level was correlated with histopathological changes of affected skin. After treatment the ECK was normalized. It is believed that QDCC could decrease the ECK in psoriatics and this effect was probably mediated by inhibiting c-myc expression. This study provided an experimental evidence for the application of QDCC in treating psoriasis. 相似文献
28.
改良超滤对婴幼儿心脏手术输血的影响 总被引:4,自引:1,他引:3
目的 观察改良超滤技术在婴幼儿体外循环心血管手术中对输血及术后出血的影响。方法 6 0例接受体外循环下心血管手术的先天性心脏病患儿 ,均分为对照组 (不接受任何超滤 )、常规超滤组 (CUF组 )和改良超滤组 (MUF组 )。观察术中库血用量、血浆用量、血球压积的变化及术后2 4h出血量 ,并用SSPS/PC进行统计学处理。结果 MUF组库血用量、血浆用量、术后 2 4h出血量显著低于对照组和CUF组 (P <0 0 1) ,且滤出水量明显多于CUF组 (P <0 0 1)。结论 在婴幼儿心血管手术中 ,改良超滤可有效排出体内水分 ,提高血球压积 ,明显减少输血及术后出血 ,是节约用血的重要手段之一。 相似文献
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30.
目的 :探讨外周血单个核细胞 (PBMC)内上游信号分子及核因子 κB(NF κB)在烧伤后炎症级联反应中的作用。 方法 :体外检测在烧伤血浆作用下的PBMC内游离Ca2 及NF κB活化的变化 ,观察钙通道阻断药对NF κB活化及IL 6、NO表达水平的调控作用。 结果 :不同时相点的烧伤血浆可使体外PBMC内Ca2 明显增加 ,培养的PBMC核内NF κB的积聚明显增加 ,培养上清中NO和IL 6高表达。应用尼莫通 (Nimodipine)和丹曲林 (Dantrium)对NF κB的活化有调节作用 ,对IL 6和NO亦有下调作用。 结论 :烧伤血浆可使PBMC内信号分子浓度明显增高 ,NF κB过度活化 ,并易位进入细胞核内 ,NF κB介导的促炎性细胞因子和NO过度表达。两种钙通道阻断药有调控细胞内信号转导的作用 ,对烧伤后全身炎症反应综合征 (SIRS)可能有防治作用 相似文献