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71.
72.
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
73.
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
74.
Objective To explore the effect and nursing main points of fluvastatin on the patients with cerebral arterial thrombosis. Methods Eighty-five patients with cerebral arterial thrombosis were randomly divided into three groups. Group Ⅰ was the negative control group. Group Ⅱ was the conventional-dose therapy group and group Ⅲ was the high-dose therapy group. Each group was treated with related therapy and care. The blood lipids in all groups were tested before the treatment, 4 weeks, 12 weeks and 24 weeks after the treatment; the carotid intima-media thickness (IMT) were measured by the Germany SEQUOIAS-512-B ultra machine before the treatment and 24 weeks after the treatment; At the same time, the side effects of fluvastatin were recorded. Results The results of blood lipid tests showed that the LDL, TC and TG in two treated groups were significantly decreased compared to negative control group (P<0.05). After treated for 24 weeks, the carotid intima-media thickness (IMT) in two treated groups were significantly reduced (P<0.05); the side effects of fluvastatin were infrequent and there was no significant different among the three groups (P>0.05). Conclusion The effects of different doses of fluvastatin on cerebral arterial thrombosis were significantly different. With the dose of fluvastatin increased, the serum LDL-L and TC reduced more obvious and the inhibition on carotid atherosclerosis shows more obvious, and the side effects did not increased. 相似文献
75.
三七粉末透皮吸收研究 总被引:9,自引:0,他引:9
目的 :研究三七粉末的透皮吸收性及选择最佳促透剂。方法 :设计体外离体透皮试验法 (即用离体鼠皮在单室扩散池中进行试验 ) ,测定不同时间三七粉末中有关成分的透皮总量 (以三七皂苷为对照 ) ,计算透皮吸收率及促透剂的促透倍数。结果 :三七粉末的丙二醇溶液有一定透皮吸收能力 ,不同浓度的氮酮 (Azone)对其具有显著的促透作用 ,但Azone的促透效果与其剂量不呈直线关系 ,5 %Azone效果好于 7%Azone。结论 :本方法简便、易于操作、重现性较好 ,可用于制剂工艺研究中促透剂的选择 相似文献
76.
化学中毒与急性缺氧的双因素联合效应的实验研究 总被引:19,自引:5,他引:14
目的 研究化学中毒与急性缺氧两因素的联合效应。方法 建立常压常氧、常压缺氧和低压缺氧3种模型,以梭曼(Soman)、氰化钠(NaCN)和4-DMAP(4-dimethylaminophenol)为代表,测定大鼠、小鼠、家猫、PC12细胞、兔血红细胞等在3种模型条件下对毒物药物的行为、生化和生理指标变化。结果梭曼单独作用可导致动物协调运动下降、脑等组织含水率增加、脑组织AChE活性降低、MR下调、NE和cAMP含量增加。急性缺氧单独作用也可引起动物协调运动及自主活动的降低、脑等组织含水率的增加、外周血和脑组织AChE活性升高、MR受体上调、NE和cAMP含量增加、4-DMAP药效升高。化学中毒与急性缺氧同时作用,上述变化更加复杂。结论 化学中毒与急性缺氧两种因素同时作用于机体,对机体产生广泛而复杂的损伤作用。此种作用为两因素的联合效应。缺氧引起的机体功能下降对联合效应的增加部分贡献较大。急性缺氧既可使重要的组织成分发生质或量的变化,也会影响某些抗毒剂的作用强度。 相似文献
77.
Pedicle screw fixation with translaminar facet joint screws for the treatment of thoracolumbar fracture 总被引:4,自引:0,他引:4
Objective:To evaluate the efficacy of Cotrel-Dubeusset (CD) instrumentation combined with translaminar facet joint screw ( TLS ) in the treatment of thoracolumbar fracture. Methods: A total of six L2-L4 spines were used to establish unstable fracture model with three-dimensional range of motion ( ROM ) of the spines measured. Fixation with CD and fixation with CD combined with translaminar facet joint screw were achieved to compare their stability. Thirty cases of thoracolumbar fracture, in whom the anterior edge of vertebral body was compressed to 59% and the posterior edge compressed to 88%, were treated by pedicle screw fixation combined with TLS. Among them, 19 received posterolateral or anterior-posterior bone grafting Results- There was significant difference in ROM between the two techniques except that in extension. In Group CD TLS, ROM was 5.38% lower, lateral bending 4.91% lower and axial rotation 11.85 % lower than those in Group CD respectively. In the clinical group, the average anterior edge restored to 97 % and posterior edge to 98%. The duration of follow-up was 5-24 months (mean, 10 months). The rate of correction loss on the anterior edge was 4.5%. Among the 19 cases of bone grafting, all of them achieved bony fusion (mean fusion time, 4.3 month) with a correction loss rate of 3.4%. Conclusions:In the treatment of thoracolumbar fracture, pedicle screw fixation combined with TLS can strengthen the stability of pedicle screws, especially antirotation stability and enhance fusion rate and reduce correction loss. 相似文献
78.
目的:总结POEMS综合征的临床特征,提高对POEMS综合征的诊疗认识。方法:回顾性分析5例PO-EMS综合征的一般资料、临床表现、辅助检查、治疗及预后等。结果:5例患者主要临床表现均有多发性周围神经病变、皮肤损害、水肿、不同程度的肝脾肿大及内分泌病变。治疗以激素及免疫球蛋白为主,预后多不良。结论:POEMS综合征是一种累及多系统的疾病,与浆细胞病关系密切,临床表现复杂多样,目前认识尚有不足,应注意多系统检查提高临床诊疗水平。 相似文献
79.
目的 评价体位、性别、手术、膀胱充盈状态对直肠癌放疗后肠受照射的影响。方法36例直肠癌患者被研究,盆腔放疗采用1后2侧野三维适形放射治疗(3DCRT)的方法,处方剂量为50Gy。利用每个计划的剂量.体积直方图(DVH)对盆腔内肠的受照剂量和体积进行分析。结果膀胱充盈差和好时肠受照射的平均剂量分别是23.8和18.3Gy(P=0.004),V45高剂量受照体积分别是15.7%和7.8%(P=O.004);体位仅对肠V15,低剂量受照体积有显著影响;性别对肠受照射的最大剂量和V15,有显著影响;手术对肠受照射的平均剂量有显著影响,分别是术前19.0Gy和术后22.5Gy(P=0.015);在仰卧或俯卧、术前或术后膀胱充盈好时均比差时肠受照射剂量要低或体积要小。膀胱充盈好和差时肠受到高剂量照射的体积V4,在俯卧位分别是15.3%和7.4%(P=0.023),术后分别是14.1%和7.2%(P=0.014),差异有统计学意义。结论 患者治疗体位、性别、手术对盆腔内肠受照射剂量和体积有一定的影响,膀胱充盈状态有显著影响。 相似文献
80.
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