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米非司酮对子宫肌瘤中血管内皮生长因子表达及微血管密度的影响 总被引:8,自引:0,他引:8
目的 :探讨子宫肌瘤中血管内皮生长因子 ( VEGF)和微血管密度 ( MVD)的关系及米非司酮治疗子宫肌瘤的机制。方法 :将 40例有症状的子宫肌瘤患者随机分成两组 ,试验组 2 0例 ,于月经周期的分泌早期给予米非司酮治疗 ,剂量为每天 2 5 mg;对照组 2 0例未给任何治疗 ,采用免疫组化的方法对子宫肌瘤中血管内皮生长因子和微血管密度进行半定量的分析。结果 :血管内皮生长因子及微血管密度在子宫肌瘤中有显著的正相关性 ( r=0 .869,P<0 .0 1)。治疗组较对照组血管内皮生长因子及微血管密度均有明显下降 ( P<0 .0 5及 P<0 .0 1)。结论 :子宫肌瘤中血管内皮生长因子与其血管生成关系密切 ,米非司酮通过抑制子宫肌瘤中血管内皮生长因子的表达 ,从而减少肌瘤血液供应 ,抑制其生长 ,改善其临床症状 相似文献
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TPA (12-O-tetradecanoylphorbol-13-acetate), a potent tumor promoter, has been shown to stimulate or inhibit cell growth depending on the cell type investigated. We recently found that RT101 cells, a transformed mouse JB6 epidermal cell line, acquired a greater growth inhibition response to TPA during conventional subcultivation. The growth of low-passage RT101 cells was slightly inhibited by TPA in monolayer culture but stimulated in soft agar. In contrast, the growth of high-passage cells was greatly inhibited by TPA in both monolayer culture and in soft agar. Inhibition was dose dependent, directly correlated with protein kinase C-activating activities of tumor promoters, and was found to be reversible. TPA-treated high-passage cells were greatly reduced in volume, showed extensive abnormal mitoses, and were more susceptible to detachment. High-passage cells were also found to be less tumorigenic as indicated by in vivo tumorigenicity assay in nude mice. TPA treatment rendered cells still less tumorigenic in the case of both cell lines. The mechanism for acquisition of increased sensitivity to TPA of RT101 cells during subculture was investigated; it involved nonrandom DNA damage and detachment of nonviable cells. The results suggest the possibility that early-passage RT101 cells contained two subpopulations, one TPA-sensitive and one TPA-resistant population. Conventional subcultivation may have selected for the former subpopulation. The sensitive subpopulation may have been irreversibly inhibited as a result of TPA-induced cell killing, possibly apoptosis. 相似文献
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Antoine Feydy MD PhD Alexandre Krainik MD Bernard Bussel MD Marc A. Maier PhD 《Journal of neuroimaging》2004,14(1):49-53
The authors report the case of a 33-year-old woman who exhibited, at the age of 17, a left-sided hemiplegia, which was followed by good motor recovery, though with a permanent deficit in fine finger movements. She had a widespread loss of neural tissue in the right hemisphere (crossed cerebrocerebellar atrophy), including (1) marked atrophy and thinning of the precentral and postcentral gyri; (2) widespread deep white matter destruction, including the corticospinal tract; and (3) crossed cerebellar atrophy. Except over the supplementary motor area (SMA), transcranial magnetic stimulation did not elicit motor evoked potentials in the affected hand. Nevertheless, during opening and closing of the affected hand, functional magnetic resonance imaging showed an activation of the lesioned primary sensorimotor cortex (SMC), as well as of the intact SMA and the parietal areas, but not of the ipsilateral motor areas. The authors speculate that recovery was achieved by a motor command generated in the SMC and the parietal cortex, passing through corticospinal axons originating in the SMA. 相似文献
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目的探讨输尿管镜气压弹道碎石治疗输尿管结石的效果。方法2004年2月~2005年3月,我们对185例输尿管结石(其中伴肾绞痛96例)采用输尿管镜取石或气压弹道碎石进行总结和分析。结果失败12例,其中6例改开放手术,6例术后3d行体外冲击波碎石。一次碎石成功率93.5%(173/185),其中上段结石为75.0%(24/32),中段为95.8%(46/48),下段为98.1%(103/105)。肾绞痛者成功率为100%(96/96)。术中输尿管损伤率2.9%(5/173),其中3例(1.7%)中转开放手术。术后肾绞痛1例。全组随访6~12个月,平均10.2月,无复发。结论输尿管镜气压弹道碎石安全有效,并发症少,是治疗输尿管中下段结石的首选方法,尤其对肾绞痛者疗效更好。 相似文献
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