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61.
Haemodynamic studies in early stroke   总被引:2,自引:0,他引:2  
Summary We investigated prospectively a consecutive series of 81 patients suffering from acute middle cerebral artery (MCA) ischaemia by transcranial Doppler ultrasonography (TCD) within 24 h of the onset of symptoms. To monitor the haemodynamic changes follow-up recordings were carried out at short intervals during the next 2–3 weeks until stable haemodynamic status was achieved. In order to estimate the value of early TCD examinations in predicting the extent of brain damage seen later on, initial MCA flow reduction was correlated with infarction size and pattern on computed tomography. Fifty-three cases showed sufficient ultrasound penetration through the temporal bone. MCA flow asymmetries were recorded in 45 patients (85%); occlusion was observed in 17. Recanalization occurred in 11 patients followed by transient hyperaemia in 3, leaving residual stenosis in 2. Initial increase of flow velocities normalized within days or weeks in 7 out of 9 patients, while 2 developed residual MCA stenosis. Nineteen patients showed a considerable flow reduction on admission, which returned to normal in 9; transient hyperaemia was detected in 5 of these. Eight patients did not show any MCA flow asymmetry. Our study revealed very variable haemodynamic changes in acute stroke, which influenced further diagnostic and therapeutic management. The high rate of spontaneous recanalizations of MCA occlusions followed by transient hyperaemia in many cases has an important bearing on thrombolytic or theological therapy. Flow velocity differences could be related to infarction pattern rather than to infarction volume. Early MCA flow asymmetry recorded by TCD within the first 24 h could not reliably predict the extent of persistent brain damage or clinical outcome.  相似文献   
62.
目的 研究支气管动脉灌注化疗联合直线加速器放射治疗Ⅲa期非小细胞肺癌 (NSCLC)的可行性及临床价值。方法  76例NSCLC患者随机分成A、B 2组 ,A组先行 2次支气管动脉灌注化疗 (BAI) ,第 2次BAI 1~ 2周后再行直线加速器放射治疗 (RT) ;B组单纯行 2次BAI (对照组 )。结果 临床疗效 ,A组 (BAI RT)和B组 (BAI)分别为 89.47%和 60 .5 3% (Ρ <0 .0 1) ;1、3年生存率 ,A、B组分别为 81.5 8%、5 0 .0 0 %和 60 .5 3%、2 1.0 5 % ( 0 .0 1<Ρ <0 .0 5 )。结论 支气管动脉灌注化疗联合直线加速器放射治疗Ⅲa期非小细胞肺癌的临床疗效和患者 1、3年生存率均显著提高  相似文献   
63.
Specific receptors for bombesin/gastrin releasing peptide (GRP) on the androgen-independent human prostate cancer cell lines PC-3 and DU-145 were characterized. No specific binding of 125I-[Tyr4]-bombesin to the androgen-dependent human prostate cancer cell line LNCaP was detectable. The binding of 125I-[Tyr4]-bombesin to PC-3 and DU-145 cells was found to be time- and temperature-dependent, saturable, and reversible. Scatchard analysis revealed a single class of binding sites with high affinity (Kd 9.8 × 10?11 M for PC-3, and 9.1 × 10-11 M for DU-145 cells at 25°C) and with a binding capacity of 44,000 binding sites/cell and 19,000 binding sites/cell, respectively. Bound 125I-[Tyr4]-bombesin was rapidly internalized by PC-3 cells. The nonhydrolyzable GTP analog GTP-gamma-S caused a dose-dependent inhibition of 125I-[Tyr4]-bombesin binding to PC-3 and DU-145 cells, indicating that a G-protein (guanine nucleotide-binding protein) couples the bombesin receptor to intracellular effector systems. Bombesin and GRP(14-27) inhibited the binding of 125I-[Tyr4]-bombesin to both cell lines in a dose-dependent manner with inhibition constants (Ki of 0.5 nM and 0.4 nM, respectively. Both cell lines express the bombesin/GRP preferring bombesin receptor subtype, since, in displacement studies, neuromedin B was more than 200 times less potent than bombesin and GRP(14-27) in inhibiting the binding of 125I-[Tyr4]-bombesin. Two synthetic bombesin/GRP antagonists, RC-3095 and RC-3110, powerfully inhibited the specific binding of 125I-[Tyr4]-bombesin with Ki 0.92 nM and 0.26 nM on PC-3 cells, and 3.3 nM and 0.89 nM on DU-145 cells, respectively. These findings indicate that the PC-3 and DU-145 human prostate cancer cell lines possess specific high-affinity receptors for bombesin/GRP, and are suitable models for the evaluation of the antineoplastic activity of new bombesin/GRP antagonists in the treatment of androgen-independent prostate cancer. © 1994 Wiley-Liss, Inc.  相似文献   
64.
目的 探讨抗CD44单克隆抗体A3D8对HL-60细胞增殖及分化的影响,寻找急性髓系白血病(AML)治疗的新靶点。方法 以AML细胞株HL-60为模型,通过观察细胞生长、形态学、表面分化抗原、细胞周期和细胞因子表达,以及应用硝基四氮唑蓝(NBT)还原实验来研究抗CD44单克隆抗体A3D8对细胞增殖及分化的影响。结果 HL-60细胞高表达CD44;A3D8以浓度和时间依赖性方式抑制HL-60细胞生长。A3D8使HL-60细胞周期阻滞在G0/G1期,CD11b、CD14表面抗原阳性率明显增高,细胞体积增大,核/浆比例减小,核染色质聚集,NBT还原实验阴性,细胞表达粒细胞集落刺激因子mRNA,呈现向单核细胞系方向分化。结论 A3D8可抑制HL-60细胞增殖,并诱导其向单核系细胞分化,CD44有可能成为AML治疗的新途径。  相似文献   
65.
目的 比较低剂量率β射线和高剂量率γ射线照射诱发肿瘤细胞生物效应特点。方法采用^32Pβ射线和^60Coγ射线照射人宫颈癌HeLa细胞系,用台盼蓝排除法和X-gal衰老细胞染色法比较两种照射肿瘤细胞死亡方式的差异。结果 ^32Pβ射线(0.375cGy/min)和^60Coγ射线(206cGy/min)照射HeLa细胞后72h的结果表明,低剂量率β射线抑制细胞增殖为渐进性,使多数的细胞在一个或几个细胞倍增周期后死亡,以增殖性死亡为主;高剂量率γ射线对细胞的抑制作用直接、迅速,细胞坏死比例高,增殖性死亡(衰老)比例低于持续低剂量照射方式。结论 不同的辐射方式对细胞的杀伤方式不同,了解其放射生物学机理有助于临床治疗方案的选择。  相似文献   
66.
目的探讨大脑中动脉(middle cerebral artery,MCA)水平段(M1)钙化的量化指标与血流动力学的关系。资料与方法搜集经头颅CT确诊M1段钙化且行经颅多普勒超声(transcranial Doppler,TCD)检查者41例,按有无钙化分为钙化组和无钙化组。分析MCA钙化组血流动力学参数与钙化量化指标是否有相关性;检验钙化组与无钙化组血流动力学参数及狭窄发生率的差异。结果MCA搏动指数(pulsatility index,PI)与钙化体积以及积分值呈线性相关;钙化组与无钙化组PI差异有统计学意义(P〈0.05),但狭窄发生率差异无统计学意义(P〉0.05)。结论MCA钙化程度与TCD反映血管弹性的PI相关,但与反映狭窄程度的血流速度无相关性。  相似文献   
67.
中切口切开法重睑成形术   总被引:5,自引:0,他引:5  
目的介绍一种简便有效,恢复快的中切口重睑成形术。详细阐述该方法的手术要点,重睑成形术所遵循的原则等。方法术前灵活定位,局部麻醉下做长15mm的小切口,去除切口内部分眼轮匝肌及睑板前脂肪.将上睑皮肤与睑板固定。结果采用中切口切开法重睑成形术180例,效果满意。结论中切口重睑成形术创伤小,恢复快,是一种简便有效的方法。术中应严格遵循无创操作,宁窄勿宽,对过度依赖额肌的患者,手术前后进行睁眼训练。  相似文献   
68.
Abstract –  The aims of this study were to investigate the incidence of coronal fracture of the anterior teeth in North Jordanian schoolchildren and to study the main predisposing factors and the factors that may affect the severity of this fracture. A study group (958) comprising schoolchildren aged 13–15 years was chosen by a simple random method from five geographical areas in Irbid Governate, Jordan. All children completed a questionnaire related to history of trauma to their anterior teeth before they had a clinical examination for lip competence, lip line and amount of fracture. Overjet was recorded from a study cast made for each student. Statistical analysis was performed using chi-square test. The results showed a prevalence of 11% of coronal fracture with female-male ratio of 1:1. An increase in the overjet more than 3 mm doubled the incidence of coronal fracture while overjet more than 6 mm increased the incidence fourfold. There was higher incidence of coronal fracture associated with lip incompetence and low lip line ( P  < 0.01). The severity of fracture increased in children with a larger overjet ( P  < 0.001). It was concluded that overjet, lip competence and lip line were important predisposing factors to coronal fracture of the anterior teeth while the severity of the fracture was mainly determined by overjet.  相似文献   
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