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71.
72.
目的研究电子在人体组织等效材料中形成的“簇点”能量分布情况,以及簇点的产生对生物效应发生的意义。方法针对电子与人体组织等效介质作用的物理机理,利用蒙特卡罗(MC)方法,按一个个相互作用事件(电离、激发、弹性散射、Auger电子发射)方式真实模拟电子在介质中的径迹,通过对这些事件进行统计分析,得到相关结论。结果电子在穿过介质过程中,主要以簇点(大于30%)形式沉积能量,并且80%以上的簇点中的能量沉积在50eV以上;簇点的密集程度与电子能量、簇点直径密切相关,簇点中能量沉积也取决于辐射类型和能量。结论簇点中的能量沉积是诱发组织细胞核内DNA分子各种损伤的最主要因素。 相似文献
73.
74.
中药安迪注射剂对人食管癌细胞的放射增敏作用 总被引:2,自引:0,他引:2
目的 :观察安迪注射剂 (Andi)对电离辐射生物学效应的影响。方法 :人食管癌细胞株 (ECA 10 9)在富氧 (空气 )和缺氧 (通 99 99%的高纯氮气 5 0min)条件下分别观察对照组、Andi组、60 Co γ线辐射和Andi +60 Co γ线辐射 4组细胞形态 (光镜 )、细胞倍增时间 (TD)、存活率 (SR)及集落存活分数 (SF)。结果 :光镜下可见Andi组、辐射组、Andi+辐射组癌细胞变性、坏死、凋亡 ,以Andi +辐射组为最显著。MTT法测定对照组、Andi组、60 Co γ线辐射和Andi+60 Co γ线辐射四组缺氧细胞的TD(% )分别为 4 6 12 ,118 72 ,6 2 81,171 0 2h ,SR分别为 10 0 % ,4 2 % ,86 % ,30 % ;各治疗组与对照组比较TD 和SR均相差显著 (P <0 0 5 )。方差分析显示 ,辐射在富氧 (F =90 19,P =0 0 0 0 1)和缺氧 (F =37 0 9,P =0 0 0 0 3)时均为SF的影响因素 ;Andi仅在缺氧时对SF是有意义的影响因素 (F =2 9 0 4 ,P =0 0 0 0 7) ,与60 Co γ线辐射合用对缺氧细胞SF的影响具有协同作用 (F =11 37,P =0 0 0 98)。用单靶多击模型拟合数据分析 ,Andi的放射增敏比 (SER)为 1 5 ,相对敏化效应 (RSE)为 5 5 %。结论 :Andi对缺氧ECA 10 9细胞具有明显的细胞毒和放射增敏作用。 相似文献
75.
Man-Hong Jim Hee-Hwa Ho Annie On-On Chan Wing-Hing Chow 《Catheterization and cardiovascular interventions》2007,69(7):969-975
BACKGROUND: Sleeve technique is a modified version of crush technique. It is specifically designed to increase the success rate of final kissing balloon inflation, which used to be a major limitation of the latter. OBJECTIVES: The aim of this study was to examine the feasibility, safety, and early clinical outcomes of sleeve technique in stenting different types (de novo, in-stent restenotic or in-stent bifurcation) of coronary bifurcation lesions at different locations. METHODS: From August 2005 to May 2006, 41 consecutive patients with symptomatic, nonleft-main coronary bifurcation stenoses of diameter narrowing >or=50% were treated with two-stent strategy, using sleeve technique. RESULTS: The mean age was 63.6 +/- 11.6 years with male predominance (70.7%). High prevalence of diabetes mellitus (31.7%), total occlusion (22.0%), and multi-vessel disease (65.9%) was observed in this cohort. Intravenous abciximab was given in 35 (85.4%) patients. Final kissing balloon inflation was successfully performed in all patients. The minimal luminal diameter in main vessel and side branch was increased from 0.97 +/- 0.53 mm and 0.81 +/- 0.45 mm to 2.76 +/- 0.34 mm and 2.22 +/- 0.35 mm, respectively. The mean procedure time was only 66.6 +/- 24.6 min. There was one (2.4%) case of subacute stent thrombosis presented as non-Q-wave myocardial infarction at day 3 postprocedure. The resultant in-hospital and 30-day major adverse cardiac event rate were both 2.4%. CONCLUSIONS: Sleeve technique is a feasible and efficient approach in stenting of coronary bifurcation stenoses. 相似文献
76.
77.
多抗甲素对人NK细胞活性的作用机理研究 总被引:1,自引:0,他引:1
作者应用单细胞细胞毒试验及形态学观察,研究多抗甲素(PAA)对人体自然杀伤(NK)细胞活性的作用机理。结果表明:PAA能增强食道癌患者淋巴细胞(PBL)明显低下的结合率(B%)和杀伤率(K%),也可增强正常人PBL的K%,但对正常人PBL的B%无影响。形态学观察发现:与靶细胞结合的PBL除大颗粒PBL外,尚有普通的非颗粒PBL,结合的靶细胞损伤首先表现为线粒体肿胀、空泡变,然后核固缩,核膜损伤,细胞严重空泡变性等,偶见靶细胞与自然杀伤细胞结合部质膜破损的现象。经PAA预处理的靶效细胞结合的形态改变无明显差异,但食道癌组的杀伤作用出现较早,且明显增强。 相似文献
78.
A 17-year-old young man presented with a highly unstable fracture dislocation of the third and fourth thoracic vertebrae with neurological deficit, in which the fractured spine had perforated the thoracic esophagus. Open reduction and internal fixation of the spinal fractures in combination with aggressive treatment of the mediastinitis caused by esophageal perforation, consisting of two re-thoracotomies, was performed. Two years after the accident, the patient had recovered well. The neurological deficit had recovered, and there were no difficulties with swallowing. 相似文献
79.
Conclusions The peroneal nerves and their blood supply are at risk during high tibial osteotomies. Fixation of nerves by fibrous tissues,
compression by tendinous arcades of the peroneus longus tendon, and narrow passages for nerves crossing dense fibrous septa
are all factors which favor the development of peroneal nerve lesions. Intraoperative soft tissue retraction and pull by retractors
may damage nerves and vessels. The muscle branch for the extensor hallucis longus muscle is particularly at risk during the
fibular osteotomy since it runs directly on the bone. 相似文献
80.
Chihaya Maesawa Gen Tamura Yasushi Suzuki Kaoru Ishida Kazuyoshi Saito Ryoichi Satodate 《Cancer science》1992,83(12):1253-1256
For the rapid and sensitive detection of p53 gene mutations in esophageal endoscopic biopsy specimens, we combined cell sorting with the polymerase chain reaction and single-strand conformation polymorphism (PCR-SSCP) analysis. Mutations in exons 5–8 of the p53 gene were investigated by FCR-SSCF analysis using 103 sorted nuclei obtained from each endoscopic biopsy specimen of 16 patients with esophageal cancer. DNAs extracted from their respective surgical specimens were investigated by a conventional method of PCR-SSCP analysis. Mutations in the biopsy specimens were detected in 6 of the 12 aneuploid tumors but in none of the 4 diploid tumors. After tumor cell enrichment by cell sorting, one mutation in exon 8 became apparent, which could not be detected from the surgical specimen by a conventional method of PCR-SSCP analysis. This method should improve the sensitivity of detecting p53 gene mutations, and provides additional information concerning the DNA ploidy pattern in the tumors. 相似文献