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41.
三氧化二锑诱导急性早幼粒细胞白血病细胞凋亡的研究 总被引:2,自引:0,他引:2
目的 研究锑剂三氧化二锑(Sb2O3)对早幼粒细胞白血病细胞株NB4凋亡的诱导作用,以寻求早幼粒细胞白血病治疗的新方法。方法 采用细胞生长曲线,形态学及硝基四氮唑蓝(NBT)还原试验,判定NB4细胞的生长,分化及功能。采用细胞周期分析和DNA电泳研究细胞凋亡。结果 Sb2O3能诱导早幼粒白血病细胞凋亡,且具有时间,剂量依赖性。结论 Sb2O3能有效地诱导早幼粒白血病细胞凋亡,提示锑剂诱导细胞半亡的疗法,有望成为临床治疗早幼粒细胞白血病的新方法。 相似文献
42.
43.
目的:为选择性脊髓血管造影和椎管内显微外科提供解剖学资料。方法:采用尸体标本30例,于节段性动脉内逐一注入红色乳胶,在完整脊髓上解剖观察。结果:每例脊髓胸腰段的后髓动脉数目5~13支,平均8.4支。后髓动脉起始情况分3型10亚型,其中后髓动脉与前髓动脉由同一肋间后动脉发出仅34支(13.5%)。胸下部及腰部后髓动脉呈典型“发卡”样折曲。后髓动脉平均外径0.37±0.12mm。约1/3标本在T_(11)~L_3间有1支后髓动脉较粗(>0.5mm),它是脊髓后下部血供的主要来源。结论:多数后髓动脉单独起始,较大的后髓动脉应引起注意。 相似文献
44.
目的 探讨经舟骨月骨周围脱位的诊断和治疗。方法 回顾性分析17例经舟骨月骨周围脱位病例,背侧型13例,掌侧型4例;新鲜损伤组10例中8例行撬拨复位成功,仅2例因舟骨对位不良接受手术治疗;陈旧性组7例中均接受手术,4例行开放复位内固定,3例行近排腕骨切除术。结果 采用Cooney评价标准,优11例,良3例,可1例,差2例,优良率82.35%。结论 经舟骨月骨周围脱位的早期治疗简单且疗效较好,而一旦误诊,则多数需手术治疗,且残留不同程度的功能障碍。提高对本病损伤机制、腕部体征和影像学特点的认识和了解,减少误诊。是提高本病预后的关键因素之一。 相似文献
45.
目的:为临床经下颌下咽后入路处理颅颈交界腹侧区病变提供解剖学基础。方法:对15例(30侧)带颈头颅标本模拟经下颌下咽后入路进行显微外科解剖,同时进行了有关的数据测量。结果:该入路浅层的重要结构均位于各自的筋膜层中,以这些结构为解剖学标志可鉴别各层并引导手术进行。咽结节是显露的上限,限制骨窗侧方显露范围的各重要结构的内缘距正中线的水平距离分别为寰枢外侧关节,左(7.78±1.03)mm,右(7.81±1.01)mm;寰枕关节,左(9.27±1.86)mm,右(9.22±1.69)mm;舌下神经管内口,左(12.76±2.77)mm,右(12.81±2.53)mm及椎动脉C2水平,左(18.36±2.27)mm,右(18.47±2.14)mm;C1水平左(25.35±2.31)mm,右(25.18±2.33)mm;穿硬膜处,左(12.69±2.42)mm,右(12.72±2.39)mm。结论:(1)经下颌下咽后入路解剖上大致可分为3个层次:浅层,深层和骨、韧带及硬膜层。(2)掌握每个层次的解剖特点及操作要点,有助于安全充分的显露和处理咽颅颈交界腹侧区病变。 相似文献
46.
本文介绍了盲人智能探路手杖的研究.该系统由单片机控制,采用两只超声波传感器的探测模式,对盲人行进路上的路况进行探测和分析,并针对不同的路况发出相应的提示信息,以达到辅助盲人安全行走的目的. 相似文献
47.
Epithelial-myoepithelial tumor is extremely rare as a pulmonary neoplasm. Only 20 cases have been reported to date, of which 14 were malignant. We report a case of intrabronchial epithelial-myoepithelial carcinoma in a 73-year-old man with a history of heavy smoking. The tumor was well-circumscribed and caused distal airway obstruction. Histologically, the tumor showed glandular and solid architecture. The glands were composed of an inner layer of epithelial cells and an outer layer of myoepithelial cells. The solid areas consisted of spindle-shaped myoepithelial cells. Immunohistochemical staining was positive for p53 and c-Kit (CD117). Focal atypia and increased mitotic activity were present, but no vascular invasion or nodal metastasis was identified. 相似文献
48.
人缺血脑组织中IP-10和IFN-γ的表达 总被引:1,自引:0,他引:1
目的:探讨趋化因子IP-10和细胞因子IFN-γ是否参与人缺血脑损伤过程。方法:将21例脑梗死死亡病例按发病持续时间分为〈7天、7~14天和15~21天3组,以非缺血侧半球做对照,用HE染色法观察炎性细胞浸润情况;通过免疫组织化学方法检测缺血半球脑组织与非缺血半球脑组织中趋化因子IP-10和细胞因子IFN-γ的表达。结果:在〈7天组和7~14天组中,缺血脑组织可见大量炎性细胞浸润。在〈7天组、7~14天组和15~2l天组中,趋化因子IP-10在缺血半球脑组织中的表达高于非缺血半球(分别是1.74倍增高,P〈0.01;1.41倍增高,P〈0.05和1.52倍增高,P〈0.01)。在对细胞因子IFN-γ的检测中发现〈7天和7~14天组中,IFN-γ在缺血半球脑组织中的表达高于非缺血半球(分别是1.65倍增高,P〈0.05和1.32倍增高,P〈0.05);在15~21天组中,IFN-γ在缺血半球与非缺血半球中的表达没有显著差异(P〉0.05)。结论:在人缺血脑组织中观察到IP-10和IFN-γ的表达,提示IP-10和IFN-γ参与了炎症反应对脑组织的损伤过程。同时也提示IP-10可能参与后期对损伤脑组织的修复。 相似文献
49.
Lin Hui Eun-Seok Shin Eun Jung Jun Youngjune Bhak Scot Garg Tae-Hyun Kim Chang-Bae Sohn Byung Joo Choi Liu Kun Song Lin Yuan Wang Zhi Jiang Hao Shi Zhentao Tang Qiang 《Yonsei medical journal》2020,61(12):1004
PurposeDissection after plain balloon angioplasty is required to achieve adequate luminal area; however, it is associated with a high risk of vascular events. This study aimed to examine the relationship between non-flow limiting coronary dissections and subsequent lumen loss and long-term clinical outcomes following successful drug-coated balloon (DCB) treatment of de novo coronary lesions.Materials and MethodsA total of 227 patients with good distal flow (Thrombolysis in Myocardial Infarction flow grade 3) following DCB treatment were retrospectively enrolled and stratified according to the presence or absence of a non-flow limiting dissection. The primary endpoint was late lumen loss (LLL) at 6-month angiography, and the secondary endpoint was target vessel failure (TVF, a composite of cardiac death, target vessel myocardial infarction, target vessel revascularization, and target vessel thrombosis).ResultsThe cohort consisted of 95 patients with and 132 patients without a dissection. There were no between-group differences in LLL (90.8%) returning for angiography at 6 months (0.05±0.19 mm in non-dissection and 0.05±0.30 mm in dissection group, p=0.886) or in TVF (6.8% in non-dissection and 8.4% in dissection group, p=0.799) at a median follow-up of 3.4 years. In a multivariate analysis, the presence of dissection and its severity were not associated with LLL or TVF. Almost dissections (93.9%) were completely healed, and there was no newly developed dissection at 6-month angiography.ConclusionThe presence of a dissection following successful DCB treatment of a de novo coronary lesion may not be associated with an increased risk of LLL or TVF (Impact of Drug-coated Balloon Treatment in de Novo Coronary Lesion; ). NCT04619277相似文献
50.
Effects of the Long-Term Depletion of Reduced Glutathione in Mice Administered L-Buthionine-S,R-sulfoximine 总被引:1,自引:0,他引:1
SUN JAMES D.; RAGSDALE S. SHA; BENSON JANET M.; HENDERSON ROGENE F. 《Toxicological sciences》1985,5(5):913-919
Effects of the Long-Term Depletion of Reduced Glutathione inMice Administered L-Buthionine-S,R-sulfoximine. SUN, J. D.,RAGSDALE, S. S., BENSON, J. M., AND HENDERSON, R. F. (1985).Fundam. Appl. Toxicol.. 5,913-919. Previous methods to depletein vivo concentrations of reduced glutathione (GSH) have notbeen able to lower tissue GSH levels for extended periods, havebeen toxic, and can alter the metabolism of xenobiotics. A possiblealternative to lower in vivo concentrations of GSH may be theuse of buthionine-S,R-sulfoximine (BSO) in the drinking waterof laboratory animals to inhibit the biosynthesis of GSH. Ithas been previously reported that 20 mM BSO in the drinkingwater given to mice was able to lower GSH levels in a varietyof tissues after 15 days. In order to more fully characterizethe in vivo depletion of GSH in tissues by ingestion of BSOand determine if this method would be suitable in studies requiringdepressed levels of GSH for extended periods, we added differentamounts of this agent to the drinking water given to mice forvarious times up to 28 days. We found that ingested BSO at thehighest concentrtion used in drinking water (30 mM) was ableto maximally lower GSH concentrations in mouse lungs, lung lavagefluid, liver, kidneys, and blood to 59.0 ? 3.6%, 35.0 ? 5.1%,44.3 ? 1.5%, 69.5 ? 3.9%, and 70.0 ? 6.0% of control mice, respectively,for up to 28 days. These lowered concentrations of tissue GSHreturned to control levels after mice were returned to untreateddrinking water for 7 days. The potential toxicity of such treatmentswas also evaluated. Levels of alkaline phosphatase, lactatedehydrogenase, glucose-6-phosphate dehydrogenase, glutathioneperoxidase, and glutathione reductase in lungs and lung lavagefluid, and total and differential cell counts from lung lavagefluid were not different between control and BSO-treated mice.This showed that BSO treatment did not produce indications oflung injury as measured by these biochemical parameters. Serumaspartyl transferase and -glutamyl transpeptidase activitieswere unaffected by the BSO treatments, indicating normal liverfunctions. Lung and liver cytochrome P-450 concentrations werealso not different between controls and BSO-treated animals.Thus, BSO in the drinking water of mice was able to effectivelylower in vivo levels of GSH without eliciting aCUte toxic responses. 相似文献