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991.
S Jiang  S Yuan  Y Wang  X Chen  Y Song  Y Yang  B Mao 《华西医科大学学报》2000,31(2):191-2, 232
In this study, the chemosensitivity of 36 cases' fresh neuroglioma specimens was examined in vitro with MTT assay. The separation method for single tumor cell, the number of planting of cells, and the dosage and acting time of drugs, which have effects on the results of MTT assay, were studied systematically. On the basis of this experiment, we established a screening method for the chemosensitivity of neuroglioma; it is accurate, rapid, and simple. At the same time, the results showed that neuroglioma was more sensitive to the chemotherapeutic drugs Vm26, DDP and MMC, and the sensitivity varied with not only the drugs but also the individuals.  相似文献   
992.
Neurofibromatosis is a dominantly inheriteddefect of the ectoderm,characterized by cafe au laitspots since the childhood and multiple tumorsderived from elements of peripheral and cranialnerves.Hernia-like tumors of various sizes can oftenbe felt under the skin and serve as a valuablecharacteristic in making diagnosis.However,theycan also affect brain,vegetative nerve system or othertissues and lead to bony abnormalities,mentaldisturbances and sometimes,endocrine abnormalities,  相似文献   
993.
Luminol-hemin system was used for chemiluminescent flow-injection analysis with immobilized glucoxidase(GOD) column to determine blood glucose. The method is fast, simple and sensitive. Blood samples were diluted to 1:1000 and pumped into the flow-injection analyzer for direct detection. The sampling frequency was 30 samples/h, with a detection limit of 7.2 x 10(-9) mol/L(1.30 micrograms/L). A column packed with 36 milligrams of CPG could be used nearly 200 times. The determination results of glucose in serum by this method were in good agreement with those obtained by the routine GOD spectrophotometric method (correlation coefficient r = 0.90, P > 0.05). Recoveries of this method were 94.0%-107.2%.  相似文献   
994.
The changes of type I collagen in the lung tissues of rats with hypoxic pulmonary hypertension (HPH) and its relationship to the mean pulmonary arterial pressure (mPAP) were investigated. The blood dynamic indexes of pulmonary circulation were measured by using Swan-Ganz. The distribution of type I collagen in pulmonary arteries, bronchi and plumonary interstitial was observed by using streptavidin peroxidase method (SP). The morphologic changes of small pulmonary arteries and the level of type I collagen were determined by image pattern analysis technique and gray scale scanning, respectively. The results showed, compared with the controls, mPAP of the hypoxic rats elevated (from 2.12 +/- 0.25 to 3.95 +/- 0.43 kPa, P < 0.01), their small pulmonary arteries, walls thickened (MT% from 16.35 +/- 2.64 to 35.83 +/- 3.55, MA% from 26.83 +/- 3.40 to 59.68 +/- 4.90, P < 0.01) and lumen narrowed. The distribution of type I collagen was mainly in the external layer of pulmonary arterial walls; the positive degrees of gray scale scanning increased and had a positive linear relationship to the mPAP and MT%. These findings suggest that the increase of type I collagen contents in pulmonary arteries is closely related to the development of HPH.  相似文献   
995.
X Liu  Z Zhang  L Yang  D Chen  Y Wang 《华西医科大学学报》2000,31(2):133-5, 142
In order to investigate the inhibition of the activation and collagen production of cultured rat hepatic stellate cells (HSC) by antisense oligonucleotides (ASON) against TGF beta 1 after cationic liposome (lipofectin) delivery, the authors synthesized a 20-mer phosphorothioate antisense oligonucleotide of TGF beta 1 mRNA, and its sense of missense oligonucleotides, and then treated the HSC with cationic liposome/oligonucleotide complexes respectively. The cellular uptake of 32P-labelled oligonucleotides was determined by liquid scintillation counting, and HSC activation was assessed by the expression of alpha-smooth muscle actin(alpha-SMA). The cellular uptake of lipofectin/32P-ASON complex was approximately five-fold higher than that of 32P-ASON alone. Cationic liposome (lipofectin) delivery significantly increased the inhibition of HSCs activation by ASON, while compared with the use of naked TGF beta 1 ASON at the same concentration (at a final concentration of 1 mumol/L, P < 0.05). However, these effects were not observed in lipofectin alone, liposome/sense or missense oligos complexes at the same concentration. The oligonucleotide or lipofectin/oligos complexes had no cytotoxicity to rat HSCs in culture. These findings suggest that cationic liposome is an effective vehicle to improve the delivery of ASON to rat HSCs in culture, and the cationic liposome/TGF beta 1 ASON complex may be useful for the treatment of hepatic fibrosis.  相似文献   
996.
为了解肝素对脂多糖诱导人肾小球系膜细胞增殖和细胞因子分泌的影响。作者采用四甲基偶氮唑蓝比色分析法及生物活性法,分别测定了人肾小球MC增殖和细胞因子的分泌情况。结果显示;在正常培养条件下,人肾上球MC分泌一定理的白细胞介素6(IL-60和肿瘤坏死因子α(TNF-α)。脂多糖诱导MC增殖及分泌IL-6,TNF-α。高浓度的肝素(500U/ml)促进MC增殖及分泌细胞因子,低浓度的肝素(5U/ml)抑制  相似文献   
997.
彩色多普勒超声评价改良迷宫手术   总被引:3,自引:0,他引:3  
为了解改良迷宫手术患者心房收缩功能恢复及心功能的情况,运用彩色多普勒超声来评价二尖瓣置换术时施行改良迷宫手术患者的手术前,后心房收缩功能和心功能情况。14例风湿性二尖瓣疾病患者,狭窄11例,关闭不全3例。对照组16例。术前,术后(半年至1年)测量左房,室,右房,室内径,M型测量左室收缩功能,左房后壁运动幅度。多普勒组织成像测量左,右房室瓣环运动速度。  相似文献   
998.
鸡胚脊髓背角感觉神经元诱向因子的初步分离及鉴定   总被引:7,自引:1,他引:6  
为探讨脊髓背角内影响SG神经元存活和生长的因素,取500只Hamburger40期鸡胚脊髓背角组织匀浆,离心后提取上清液,用SDS-PAGE电泳初步分离脊髓背角内的蛋白质。以简易细胞钓蛋白带(PBFC)技术找寻有神经细胞贴附的蛋白带并求相对迁移率(Rf)。将有神经细胞贴附的各Rf范围凝胶剪下并将胶内各蛋白带电转移至硝酸纤维膜上,用NGF、BDNF、NT-3、GDNF兔抗血清于硝酸纤维膜上分别进行W  相似文献   
999.
血管内皮生长因子165反义RNA治疗人脑胶质瘤的实验研究   总被引:8,自引:0,他引:8  
目的 探讨应用血管内皮生长因子165(VEGF165)反义RNA治疗人脑胶质瘤的可行性。方法 构建和鉴定反义VEGF165真核表达载体;将其转染入人脑胶质瘤细胞SHG44,检测其转染前、后的生物学性状;比较转染前、后SHG44细胞的裸鼠皮下致瘤性;分别应用免疫印迹、免疫组织化学、微血管计数、电镜和流式细胞仪检测上述改变。结果 成功构建反义VEGF165真核表达载体并在SHG44细胞获得表达,该细胞  相似文献   
1000.
阿法骨化醇对去卵巢大鼠骨质疏松症防治作用的实验研究   总被引:9,自引:2,他引:7  
目的 探讨从骨量、骨结构、骨力学和骨转换等方面研究阿法骨化醇对去卵巢大鼠骨质疏松症的防治作用。方法 53只健康雌性未交配6个月龄Wistar大鼠分为6组(1)基线组(Base)6个月龄时处死;(2)假手术组(Sham);(3)去卵巢(OVX)治疗前对照组(OVXb);(4)OVX治疗末对照组(OVXe);(5)OVX后雌激素治疗组(O+E);(6)OVX后阿法骨化醇治疗组(O+VD)OVX后6周开  相似文献   
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