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21.
Objective To elucidate the effect of FasL gene expression on the proliferation and apoptosis of hypoxic rectal carcinoma cells. Methods The normoxic expression level of FasL in HR-8348 subtype cells (HR-8348B, HR-8348L, HR-8348F and HR-8348As) with different invasive power were verified by Western blot. Hypoxia models for HR-8348B, HR-8348L, HR-8348F and HR-8348As were constructed with chemical modeling, then the FasL levels in all groups at 12 h after hypoxia were quantitated by Western blot. Distribution of different cell life cycles was determined with flow cytometry. Cell reproductive activities were detected with MTT method, and cell apoptesis was assessed with TUNEL. Results FasL protein was pigmentized at the position of 40 000 by Western blot, and the expression level of FasL was significantly higher in HR-8348F cells than those in HR-8348B, HR-8348L and HR-8348As cells(F=361.149, P<0.01) in normoxia. At 12 h after hypoxia, the FasL level was also significantly higher in HR-8348F cells than those in other groups (F=278.766, P<0.01), but was not markedly different as compared to themselves in normoxia (t=1.762, P>0.05). The proliferation index was significantly higher in HR-8348F (60.43±3.72) than those in HR-8348B (40.01±3.30), HR-8348L (41.30±4.06) and HR-8348As cells (35.87±4.39), respectively (F=39.477, P<0.01). However, both inhibition rate of proliferation and apoptotic index were remarkably lower in HR-8348F (17.30±1.98 and 13.10±1.04) than those in HR-834B (33.70±4.33 and 21.60±1.31), HR-8348L (34.20±3.92 and 20.10±1.15), and HR-8348As (38.00±4.55 and 23.90±1.23), respectively (F=28.811 and 76.462, respectively, P<0.01). Conclusion The expression enhancement of intracellular FasL in rectal carcinoma in hypoxia can lead to accelerated proliferation and reduced apeptosis of cells, which will promote tumor cells to adapt microenvironmental hypoxia. 相似文献
22.
外科危重病人输血适应证选择及合理应用 总被引:2,自引:0,他引:2
输血在医疗活动中是很普遍的,美国北卡大学医学实验室的Hay等[1]在对北卡大学附属医院2004年死亡的病人进行回顾性调查分析后发现,有67.9%的病人输过血。大量的输血也造成了血源的紧张,目前我国无偿献血所能提供的血量只相当于临床需要量的60%,而输血的并发症也一直困扰着我们, 相似文献
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Structural vertebral changes in the horizontal plane in idiopathic scoliosis and the long-term corrective effect of spine instrumentation 总被引:1,自引:0,他引:1
Summary The rotation and structural changes of the apex vertebra in the horizontal plane as well as of the thoracic cage deformity were quantified by measurements on computed tomography (CT) scans from patients with right convex thoracic idiopathic scoliosis (IS). The CT scans were obtained from 12 patients with moderate scoliosis (mean Cobb angle 25.8°, r 13°–30°) and from 33 with severe scoliosis (mean Cobb angle 46.2°, r 35°–71°). In addition, CT scans of thoracic vertebrae from 15 patients without scoliosis were used as reference material. Ten of the scoliotic cases had had Cotrel-Dubousset instrumentation (CDI) and posterior fusion and had entered a longitudinal study on the effect of operative correction on the re-modelling of the apical vertebra. An increasingly asymmetrical vertebral body, transverse process angle, pedicle width and canal width were found in the groups with scoliosis as compared with the reference material. Vertebral rotation and rib hump index were significantly larger in patients with early and advanced scoliosis than in normal subjects. The modelling angle of the vertebral body, the transverse process angle index and the vertebral rotation in relation to the middle axis of the thoracic cage were significantly greater in patients with severe than with moderate scoliosis. The results of this longitudinal study suggest that the structural changes of the apical vertebra regress 2 years or more after CD instrumentation. 相似文献
26.
高强度超声对犬前列腺组织损伤的实验研究 总被引:1,自引:0,他引:1
目的 探讨经尿道高强度超声 (transurethralhighintensityultrasound ,TUHIU)治疗良性前列腺增生症 (benignprostatichyperplasia ,BPH)的有效性和可行性。方法 对犬前列腺进行TUHIU辐照处理 ,辐照后不同时期处死动物以观察其急性、亚急性和慢性期大体及组织病理变化。同时观察辐照前后影像学变化。结果 TUHIU辐照前前列腺部尿道平均最大宽度为 0 66± 0 12 ( x±s)cm ,辐照 3周后前列腺部尿道平均最大宽度为 2 11± 1 0 7cm ,较辐照前显著增宽。辐照后可见靶区内尿道周围腺体发生凝固性坏死 ,3 0~ 60天后坏死组织脱落尿道呈囊腔状。光、电镜下均可见腺上皮及基质细胞发生均匀性凝固性坏死。辐照后经腹B超示前列腺内部出现液性暗区 ,前列腺呈囊性改变。辐照后即刻各犬均出现短暂性尿潴留、尿频、尿线变细 ,1月后恢复正常。结论 TUHIU可破坏前列腺组织 ,明显增加前列腺部尿道宽度。 相似文献
27.
目的 探讨一种高效便捷的99mTc CEA Fab标记化合物的研制方法。方法 采用 2 亚氨噻酚盐酸盐修饰CEA Fab ,通过GH转换 ,将99mTc标记在结肠癌单克隆抗体CEA Fab上。结果 已修饰抗体的标记率为 93.5 %,99mTc胶体含量为 2 .5 %,标记化合物有良好的稳定性和免疫活性。结论 成功地建立了结肠癌单抗片断CEA Fab的99mTc标记方法 ,该技术可以应用于其他抗体片段标记领域。 相似文献
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新生儿呼吸机相关性肺炎临床与病原学分析 总被引:1,自引:0,他引:1
目的分析新生儿重症监护病房(NICU)呼吸机相关性肺炎(VAP)的临床病原学特点。方法以2004年1月。2006年12月我院NICU机械通气患儿为对象,分析vAP患儿的临床资料、病原学构成及药敏实验结果。结果82例机械通气患儿中,49例发生VAP,发生率为59%,病原体以革兰阴性茵为主,细菌耐药高。结论明确VAP的发病因素和致病菌,有利于合理运用抗生素和防治VAP。 相似文献