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41.
Objective To investigate the inhibitory effects of fms-like typrosine kinase receptor sFh-1 on retinal neovascularization (RNV). Methods Recombinant lentivirus sFh-1 ( 2-3 ) and sFh-1 ( 2-4 )expressing the sFh-1 (2-3) and (2-4) immunoglobulin-like regions of sFh-1 were constructed. 96 seven-dayold C57/6J mice were randomly divided into 4 groups with 24 mice in each group. Group 1 : normal control;group 2: experimental control; group 3: sFlt-1(2-3); group 4: sFlt-1(2-4). The mice in group 2-4 were exposed to hyperoxia with (75±2)% O2 for 5 days and then returned to normoxia with 21% O2 ; the mice  相似文献   
42.
将3′,5′-环胞苷二棕榈酸酯包封于脂质体中.药效学研究表明,药物的脂质体剂型对腹水型肝癌细胞的抑制率比游离药物以及阿糖胞苷脂质体的抑制率高1倍以上.化学动力学实验显示,在pH为6.9时,脂质体中药物的分解反应速度比游离药物慢得多,其有效期比游离药物长3倍以上.用荧光法研究药物分子在脂双层上的状态,探讨了药物包封于脂质体中抗癌活性及化学稳定性提高的原因.  相似文献   
43.
应用0.5%环孢霉素A(cyclosporin A,CsA)滴眼治疗穿透性角膜移植术后发生免疫排斥患者16例(16只眼),治愈9只眼,好转6只眼,无效1只眼。随访5~24个月,其中2只眼因停药复发,1只眼于拆线后复发,继续用药或增加给药次数后治愈。研究表明0.5%CsA滴眼剂治疗术前移植床条件较好,角膜移植术后发生免疫排斥的病例可得到良好疗效;而对术前移植床条件较差,角膜移植术后发生免疫排斥的病例有一定的疗效。作者对眼局部应用CsA治疗角膜移植排斥的疗效和作用机理进行了讨论。  相似文献   
44.
纳米抗菌剂抑菌杀菌性能研究   总被引:25,自引:0,他引:25  
目的:检测纳米抗菌剂对标准菌株的杀菌、抑菌性能和高温对其抑菌效果的影响。方法:目标菌为大肠杆菌、金黄色葡萄球菌和白色念珠菌,通过悬液定量杀灭试验和抑菌环试验检测纳米抗菌剂的杀菌、抑菌能力。结果:水溶性纳米抗菌膜溶于5ml灭菌水中作用l0min可杀灭95.39%的金黄色葡萄球菌和93.28%的白色念珠菌,复合了纳米银的抗菌医用棉条、烧烫伤贴、创伤贴对大肠杆菌和金黄色葡萄球菌的抑菌环直径大于l0mm,对白色念珠菌的抑菌环直径大于7mm。结论:纳米抗菌剂对细菌繁殖体和白色念珠菌具有良好的抑菌、杀菌作用,高压灭菌处理对纳米银抗菌剂抑菌效果影响不大,但织物构造对其抑菌效果有影响。  相似文献   
45.
目的 :探讨近视眼的角膜表面形态及屈光参数的变化规律。方法 :用电脑验光仪及计算机辅助的角膜地形图仪为 2 0 0 0只近视眼 (分为低度、中度、高度、超高度 4组 )行验光及角膜摄像分析。以 2 82只正视眼作对照组。结果 :低度、中度、高度及超高度组角膜表面形态近圆形 (圆形及椭圆形 )分别为 2 8.39% ,2 7.73% ,2 8.0 4 % ,2 0 .0 8% ,低于正视组的 4 1.6 8% (P<0 .0 5 ) ;领结形 (对称及非对称领结形 )分别为6 5 .5 1% ,6 5 .91% ,6 4.87% ,72 .32 % ,高于正视组的 5 2 .0 7% (P <0 .0 5 ) ;角膜表面规则指数 (SRI)明显高于正视组 ;角膜表面不规则指数 (SAI)与正视组差异无显著性 (P >0 .0 5 ) ;平均角膜屈光度 (ACP)和散光度(CYL)显著大于正视组 (P <0 .0 5 )。结论 :近视眼角膜表面形态及屈光参数较正视眼有明显变化。LASIK术前详细分析角膜地形图为设计个性化手术方案及预测疗效提供了重要依据。  相似文献   
46.
口腔鳞癌巨噬细胞和微血管的空间关系   总被引:7,自引:0,他引:7  
目的 :研究鳞癌组织中肿瘤相关巨噬细胞 (TAMs)和肿瘤微血管在局部空间的相互关系。方法 :采用免疫组化双染的方法观察标记巨噬细胞和微血管。结果 :在口腔鳞癌中TAMs密集的区域与微血管密集区域 ,两者的TAMs和微血管记数呈现相反的关系 (P <0 0 0 1)。结论 :在口腔鳞癌中TAMs迁徙、聚集到缺氧的区域 ,参与肿瘤的血管生成 ,但具体机制仍需进一步研究  相似文献   
47.
目的 评价翼状胬肉术前术后的角膜屈光状态及其与术前胬肉大小的关系,探讨胬肉手术的时机与必要性。方法 对29例(32只眼)翼状胬肉患者进行胬肉侵入角膜的长度测量,并于术前术后行角膜地形图检测,以资对比。结果 32只眼均有程度不同的顺规散光,其大小与翼状胬肉侵入角膜的长度有关。手术显著降低了角膜散光,提高了角膜平均屈光力。手术导致的角膜散光变化、角膜平均屈光力变化和术前胬肉大小显著相关。结论 翼状胬肉的生长和手术切除对角膜的屈光状况有显著影响,胬肉越大,这种影响就越大。当胬肉较大时,角膜地形图的改变可能包括一部分假象。  相似文献   
48.
Frontal stimulation, i.e. electrical stimulation where electrodes are pressed on the skin of the intact frontal skull of mice or rats, may represent a more humane alternative to the widely used transcorneal stimulation to induce electroshock seizures. The aim of this work was to directly compare transcorneal and frontal stimulation in eliciting maximal electroshock-induced seizures (MES) in mice and the anticonvulsant effect of carbamazepine (CBZ) and phenytoin (PHT) on thus produced seizures. In addition, we stimulated mice and rats repeatedly via transcorneal and frontal electrodes to see whether kindling is produced by this procedure. Two electroshock tests were used in mice, i.e. maximal electroshock seizure threshold (MEST) test and MES generated by supramaximal stimulation (50 mA). Frontal stimulation resulted in lower convulsive threshold than in the case of corneal stimulation. Both CBZ and PHT produced dose-dependent increases in seizure threshold for both sites of stimulation, i.e. transcorneal and frontal. As regards type of electrodes, higher doses of PHT were required to increase seizure threshold in the case of frontal than transcorneal stimulation. Supramaximal stimulation (50 mA) yielded comparable ED50 values regardless of the site of stimulation. Furthermore, once-daily stimulation of mice, regardless of the placement of electrodes, did not induce any changes in convulsive threshold. We also attempted to kindle mice and rats via corneal and frontal electrodes by repetitive electrical stimulation using currents which initially did not produce generalized clonic seizures. Mice were stimulated once daily for 2 s with 3 mA (corneal electrodes) or 2 mA (frontal electrodes) and rats were stimulated twice daily for 4 s at 8 mA (corneal electrodes) or 5 mA (frontal electrodes). With corneal stimulation in rats there was a clear progression of kindling development which was not the same in nature when compared with corneally-stimulated mice. Frontal stimulation did not produce kindling. Moreover, corneal stimulation was better tolerated by rats, while in mice high mortality was seen after either method of current delivery. Our data indicate that frontal electrodes can be used as an alternative to transcorneal stimulation to produce MES by supramaximal or threshold current intensities as screening procedures in antiepileptic drug (AED) development. Nevertheless, this type of stimulation cannot be used to produce minimal electroshock seizures and seems not to be useful to produce kindling in rats and mice.  相似文献   
49.
大鼠背部20%光辐射Ⅲ度烧伤7天后的焦痂提取液及1:4、1:8稀释液能对正常大鼠肝线粒体呼吸产生明显的抑制作用,相同方法制成的正常皮提取液只呈轻度抑制,1:4稀释液已无抑制作用,两者丙二醛含量相差悬殊,丙二醛含量与抑制率呈相关,但进一步分析表明这种相关为共存现象,丙二醛含量增高不是呼吸率下降的直接原因。丙二醛增高与膜脂双层的破坏有关,内膜能化作用实验表明,当膜脂受到一定程度破坏时,能化作用受到抑制。然而在能化作用未表现异常时,呼吸率已呈一定程度抑制,故呼吸率抑制还受到提取液其他组分的影响。  相似文献   
50.
Functional vascular connections must form rapidly to prevent ischemic damage to grafted neural tissues. The temporal sequence by which transplant circulation is re-established provides information about the angiogenic capacity of either intact or damaged CNS blood vessels. This study compares the time course and mechanism of vascular reperfusion in allografts of superior cervical ganglia or adrenal medulla inserted either into the fourth ventricle or directly into the parietal cortex of perinatal rats. Tritiated thymidine was administered to recipients to determine angiogenic patterns at various postoperative time periods. After processing for light microscopic autoradiography, host and graft endothelial labelling indices were determined in order to establish the temporal sequence and location of vascular proliferation. Correlative electron microscopy depicted the morphological changes in transplant vasculature. Some recipients were prelabelled with 3H thymidine prior to transplantation to determine if host vessels invaded the grafts. Intraventricular graft vessels initially collapsed but sustained minimal ischemic damage and were completely reperfused by 24 hours postoperative. Adjacent intact host vessels attained peak 3H thymidine incorporation at 20 hours. Intrinsic graft vessels were radioactively labelled only after 48 hours. Intraparenchymal transplants surrounded by minimal trauma exhibited a similar temporal sequence of reperfusion and host endothelial proliferation. Intrinsic graft vessels in intraparenchymal grafts sustained more severe damage. With increased trauma, a concomitant delay in graft reperfusion time was observed. Grafts within prelabelled hosts rarely contained any labelled endothelium, indicating that anastomotic connections were made between original, intrinsic graft vessels and nearby host vascular sprouts. This study demonstrates that mature autonomic tissue stimulates the growth of adjacent host vessels when transplanted to undamaged brain surfaces. The anastomosis of nascent host vessels with pre-existing graft vessels is responsible for the rapid re-establishment of circulation within the transplants. A similar mechanism occurs within intraparenchymal grafts, although the rapidity of reperfusion appears to be predicated on the amount of trauma present at the graft site.  相似文献   
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