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111.
Chuan-Bin Guo Nian-Hui Cui Guang-Yan Yu Ding-Xin Liu Shu-Cong Meng Qing Song 《Journal of oral and maxillofacial surgery》2003,61(8):909-912
PURPOSES: Inhibition of cerulenin on the endogenous fatty acid synthetic activities of oral squamous cell carcinoma (OSCC) and normal oral mucosa was assayed. METHODS: Squamous cell carcinoma and normal oral mucosa were collected fresh from surgical specimens. The collected tissues were minced in RPMI 1640 and divided into 3 groups: cerulenin treated, dimethylsulfoxide treated, and control. The tissues were incubated in [1(2)-(14)C]acetic acid, sodium salt for the last 2.5 hours of the treatment at 37 degrees C in 5% CO(2). After labeling, total lipids were extracted and counted for (14)C by scintillation counting. RESULTS: Endogenous fatty acid synthetic activities of oral squamous cell caranoma in the cerulenin-treated group decreased by 19% at 1 hour, 64% at 2 hours, and 87% at 4 hours; remained nearly unchanged in the dimethylsulfoxide-treated group; and increased slightly in the control group. The oral mucosa tissues were only mildly affected by cerulenin in fatty acid synthesis. CONCLUSIONS: Cerulenin significantly inhibits fatty acid synthetic activity in squamous cell carcinoma and only mildly affected the oral mucosa, indicating that the fatty acid synthetic pathway may be exploited as a target for developing anticancer drugs. 相似文献
112.
113.
Jin-Seon Song Francis K Mante William J Romanow Syngcuk Kim 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2006,102(6):809-815
OBJECTIVE: To evaluate the chemical composition and crystalline structures of Portland cement, gray ProRoot MTA (gray MTA), white ProRoot MTA (white MTA), and gray MTA-Angelus. STUDY DESIGN: X-ray diffraction analysis was used to identify and characterize crystalline phases, and energy dispersive x-ray spectrometer was used to determine the chemical composition of the test materials. Both powder form and set form were examined. RESULTS: The crystalline structure and chemical composition of gray and white MTA were similar except for the presence of iron in gray MTA. Both were composed mainly of bismuth oxide and calcium silicate oxide. Portland cement was composed mainly of calcium silicate oxide and did not contain bismuth oxide. Gray MTA-Angelus had a lower content of bismuth oxide than ProRoot MTA. There were no noticeable differences in the chemical composition and crystalline structures between the powder and set forms of any of the material tested. CONCLUSION: Portland cement differed from the MTA by the absence of bismuth ions and presence of potassium ions. Gray MTA contained a significant amount of iron when compared with white MTA. In addition, gray MTA-Angelus had a lower content of bismuth oxide than ProRoot MTA. 相似文献
114.
目的探讨用游离自体腹白线片修补急性十二指肠溃疡穿孔的应用价值。方法从2006年1月至2006年7月对13例用自体腹白线片修补急性十二指肠溃疡穿孔的病人的临床资料和随访情况进行回顾性分析,其中2例穿孔大于2cm2,平均手术时间60分钟,平均失血量20ml,平均住院天数9±1天。结果游离自体腹白线片修补急性十二指肠溃疡穿孔13例均痊愈出院。随访15天至6个月,无手术并发症。结论本方法操作较简单、安全、效果好,其适应症广,是一种可行的新方法。 相似文献
115.
失血性休克大鼠肠上皮细胞线粒体DNA腺苷三磷酸酶6,8基因表达及线粒体功能的改变 总被引:1,自引:0,他引:1
目的 探讨失血性休克大鼠肠上皮细胞线粒体DNAATPase 6 ,8基因表达及线粒体功能的改变 ,为阐述休克肠道靶学说和线粒体能量代谢提供分子生物学基础。 方法 2 4只Wistar大鼠随机分为休克前组和休克 1,2 ,3,4 ,5h组。采用RT -PCR方法观察线粒体ATPase 6 ,8mRNA量的改变。用透射电镜观察、生物体视学测量线粒体形态 ,用Clark氧电极测线粒体呼吸功能。 结果 失血性休克 1,2h ,ATPase 6 ,8基因表达增强 ,以后渐减弱 ,至休克 5h表达最低 ,ATPase 6 ,8基因表达分别降为正常的 6 9.3%和 78.4 % (P <0 .0 1和P <0 .0 5 )。失血性休克 2h和5h ,线粒体平均截面积、长径、面密度、体密度均显著增加 (P <0 .0 1) ,休克 5h时分别为休克前的2 .0 ,1.4 5 ,1.4 7,2 .2 2倍。休克 5h ,线粒体比表面和数密度分别下降 32 %和 2 4 % (P <0 .0 1和P <0 .0 5 ) ,嵴和基质破坏明显。失血性休克后肠上皮细胞线粒体呼吸控制率和氧化磷酸化效率比休克前显著降低 (P <0 .0 1)。 结论 失血性休克时大鼠肠上皮细胞线粒体DNAATPase 6 ,8基因表达下调 ,线粒体呼吸功能出现障碍 ,线粒体超微结构发生了改变 相似文献
116.
垂体腺瘤是发生于垂体前叶的良性肿瘤,约占中枢神经系统肿瘤的10%-20%,而无功能微腺瘤占到成人尸检的23%左右。生理上根据免疫组化将垂体腺瘤按功能分为有激素分泌活性腺瘤(functioning pituitary adenoma,FPA)和非激素分泌活性腺瘤(non—functioning pituitary adenoma,NFPA)两大类。[第一段] 相似文献
117.
目的:掌握中国维和部队士兵性观念和性心理状况,力图加以正确引导和心理干预。方法:在维和任务中期,采用自编问卷,对314名中国驻利比里亚维和士兵进行性观念和性心理方面的调查。结果:超过90%的士兵性知识来源于自学,部分士兵性知识相对缺乏,通过集训的学习,仍有77%的战士对“艾滋病”有恐惧感。与未婚士兵相比,已婚士兵显示出更成熟的性心理(P<0.05);而性观念上差异没有显著性(P>0.05)。结论:针对不同群体进行有效的心理干预和心理疏导,能让士兵理智地对待自己的性欲和愿望,把性能量升华为内在的工作动力,创造性地开展维和工作。 相似文献
118.
目的:通过观察妇宝胶囊对动物出凝血时间、血液凝固系统的影响,探讨妇宝胶囊的止血机制。方法:采用毛细玻璃管法测定小鼠凝血时间(CT),用断尾法测定出血时间(BT);用ACL-200型血液凝集仪测定大鼠凝血酶原时间(PT)和部分凝血活酶时间(APTT)。结果:妇宝胶囊能明显缩短小鼠CT、BT,缩短大鼠PT和APTT。结论:妇宝胶囊的止血机制主要通过促进内源性和外源性凝血系统,抑制纤维蛋白溶解系统达到目的。 相似文献
119.
Si Young Song 《Taehan Sohwagi Hakhoe chi》2007,49(5):271-279
Cancer is one of the leading causes of death in human, and among various cancers, gastrointestinal cancers occupy more than 55%. Gastric cancer is the first leading cause of cancer-related mortality in the world and the number of pancreas and colon cancers are increasing remarkably during last two decades which will continue to increase in the future. Even though the clinical importance of gastrointestinal cancers is very high and endless efforts has been made to develop novel diagnostic and therapeutic methods to improve the patient's quality of life and survival, the realistic advance in the actual survival benefit of the cancer patients are still strongly required. Nanotechnology has the power to radically change the way of cancer diagnosis and treatment. Currently, there is a lot of researches on novel nanodevices capable of detecting cancer at its earliest stage, pinpointing its location within the body, and delivering anticancer drugs specifically to the malignant cells. Nanoscale devices can readily interact with biomolecules both on the cell surface and within the cell. In addition, nanoscale devices are already proven that they can deliver therapeutic agents to target cells even within specific organelles. Major areas in which nanomedicine is being developed in cancer include early detection and proteomics, imaging diagnostics and multifunctional therapeutics. Because nanotechnology would provide a technical power and tool that enable new diagnostics, therapeutics, and preventives to keep pace with today's explosion in knowledge in the future, it would be very useful to know the perspectives in the direction of nanotechnology as a major clinician responsible for the patients with gastrointestinal malignancies. 相似文献
120.
Images in emergency medicine 总被引:1,自引:0,他引:1