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71.
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
72.
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
73.
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
74.
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
75.
Images in emergency medicine 总被引:1,自引:0,他引:1
76.
目的 通过比较伴重症肌无力(MG)的胸腺瘤、单纯胸腺瘤和正常胸腺中HLA类分子表达强度的差异,探讨伴MG胸腺瘤内异常微环境因素。方法 采用免疫组化方法检测HLA-Ⅰ(A、B、C)和HLA-DR表达,光镜下扫描图像入计算机,处理后得HLA类分子染色的积分光密度以分析其表达强度。结果 皮质型胸腺瘤HLA-DR表达强度减弱,伴MG皮质型胸腺瘤HLA-DR表达强度减弱程度更甚。结论 伴MG的皮质型胸腺瘤表达HLA-DR强度减弱可能是其内的胸腺细胞分化、发育异常的原因,可能与MG发病相关。 相似文献
77.
78.
胆管癌误诊和漏诊的影像学分析 总被引:1,自引:0,他引:1
目的:分析胆管癌误诊和漏诊的原因,评价不同检查方法对肝门区胆管癌诊断的价值,提高胆管癌的影像学诊断和鉴别诊断水平。方法:收集31例临床和病理诊断为胆管癌的病例(ERCP检查31例,B超检查31例,25例CT检查,11例行MRCP检查),回顾性分析不同检查方法的影像学表现。结果:31例中发生在肝门区的胆管癌25例。2例初次ERCP显示胆管内出血,再次行鼻胆管造影后诊断为胆管癌,4例合并有总胆管结石。6例为总胆管中下段癌。初次诊断准确性为90.3%。11例MRCP中9例显示病变,2例显示不满意,7例显示胆管或胆囊结石。25例CT中23例显示肝内胆管扩张,9例显示肝门区肿块,2例见后腹膜转移淋巴结,1例见肝内多发性转移瘤。12例初次诊断正确(48%)。B超检查23例提示肝内胆管扩张,6例提示总胆管结石,18例诊断为胆囊炎、胆囊结石,8例提示胆管占位(25.8%)。结论:良好的直接胆管造影是诊断胆管癌的金标准,MRCP可以在一定程度上准确显示病变的范围,是ERCP的良好补充,很大程度上取代了诊断性ERCP;CT诊断的关键在于显示扩张的胆管和梗阻的定位,肝门区梗阻多为胆管癌所致。多种影像检查方法的结合明显提高了诊断的准确性,对胆管癌治疗方案的选择有重要价值。 相似文献
79.
综合医院医务人员感染SARS情况对比分析 总被引:3,自引:1,他引:2
目的:分析在防治SARS工作初期、后期医务人员感染SARS的差异和采取的对策,为减少综合医院内医务人员SARS的感染提供参考。方甚:对本院自2003年3月24日至6月2日SARS诊断治疗任务中发生的医务人员的感染原因和采取的对策进行回顾性分析。结果:防治SARS工作初期,急诊科交叉感染和在SARS隔离病房等与SARS患者密切接触的工作岗位,共有17名医务人员感染,及时隔离治疗,均已痊愈,未造成医护人员的进一步交叉感染:经加强防护培训,改善工作条件,在防治SARS工作后期,仅发生2名护工感染,亦已痊愈,派出非典医疗队实现零感染。结论:综合医院内医务人员感染SARS的问题严峻,加强医院内的全员防护培训,按岗分区管理,改善医务人员的工作条件和病人的隔离观察环境,做好监督检查,积极应对,可以减少医务人员的SARS感染。 相似文献
80.
Inhibition of angiogenesis by antibody blocking the action of proangiogenic high-molecular-weight kininogen 总被引:7,自引:1,他引:6
R. W. Colman R. A. Pixley I. M. Sainz J. S. Song I. Isordia-Salas S. N. Muhamed † J. A. Powell Jr † S. A. Mousa† 《Journal of thrombosis and haemostasis》2003,1(1):164-170
Summary. Previously we demonstrated that domain 5 (D5) of high-molecular-weight kininogen (HK) inhibits neovascularization in the chicken chorioallantoic membrane (CAM) assay and further found that kallikrein cleaved HK (HKa) inhibited FGF2-and VEGF-induced neovascularization, and thus was antiangiogenic. In this study, we sought to demonstrate whether uncleaved HK stimulates neovascularization and thus is proangiogenic. The chick chorioallantoic membrane was used as an in ovo assay of angiogenesis. Low-molecular-weight kininogen stimulates angiogenesis, indicating that D5 is not involved. Bradykinin stimulates neovascularization equally to HK and LK and is likely to be responsible for the effect of HK. A murine monoclonal antibody to HK (C11C1) also recognizes a similar component in chicken plasma as detected by surface plasmon resonance. Angiogenesis induced by FGF2 and VEGF is inhibited by this monoclonal antibody and is a more potent inhibitor of neovascularization induced by VEGF than an integrin αv β3 antibody (LM 609). Our postulate that C11C1 inhibits the stimulation of angiogenesis by HK was confirmed when either C11C1 or D5 completely inhibited angiogenesis in the CAM induced by HK. Growth of human fibrosarcoma (HT-1080) on the CAM was inhibited by GST-D5 and C11C1. These results indicate HK is proangiogenic probably by releasing bradykinin and that a monoclonal antibody directed to HK could serve as an antiangiogenic agent with a potential for inhibiting tumor angiogenesis and other angiogenesis-mediated disorders. 相似文献