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131.
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
132.
脑外伤后脑干组织中血管内皮细胞及血浆蛋白分布改变的免疫?… 总被引:1,自引:0,他引:1
目的:探讨脑外伤后脑干组织中血脑屏障和神经细胞的病理学改变.方法:采用免疫组化染色显示人体脑干组织中的血管内皮细胞(CD31)和某些血浆蛋白(白蛋白及 IgM).结果:1.在正常脑干组织中, CD31阳性物呈连续的线条状,围成规则的血管腔,其周围无明显间隙;血浆蛋白位于血管内,未见到血浆/蛋白阳性神经细胞或神经纤维.2.脑外伤后,脑干中的 CD31阳性物呈不规则弯曲的小片段状,围成不规则的血管腔,其周围间隙明显增宽;同时可见到白蛋白及IgM阳性神经细胞和神经纤维.结论:脑外伤后,脑干组织中的血脑屏障受到了破坏,而且神经细胞也有不同程度的损伤. 相似文献
133.
134.
瞬间反应式二次谐波显像评价正常犬肝脏超声学造影的实验研究 总被引:2,自引:1,他引:1
目的:评价瞬间反应二次谐波显像(Transient response second harmonec imaging,TRSHI)对正常肝脏声学造影的增强效果及动态变化规律,并与常规连续二次谐波显像进行对比分析。方法:6只健康杂种犬 经外周静脉注射氟碳声学造影剂,分别用常规二次谐波显像和瞬间反应式二次谐波显像扫描肝脏。造影效果评价使用视觉评分和视频密度分析。结果:常规二次谐波显像有4次I级增强、4 相似文献
135.
136.
目的 总结可吸收内固定材料自身增强聚丙交脂(SR-PLLA)的临床应用体会。方法 采用波兰进口SR-PLLA螺钉、棒、线治疗四肢松质骨骨折22例,随访摄片观察骨折愈合情况,检查关节活动功能。结果 术后有两侧出现并发症,一例局部少量积液,经2次穿刺抽液加压包扎痊愈;一例患者过早去除石膏功能锻炼,螺钉松动滑出,经手术复位石膏外固定治愈,无感染或过敏等情况发生。结论 掌握可吸收材料的生物力学特点,并选择适当的病例,可以最大限度地发挥可吸收内固定材料的优势。 相似文献
137.
From the roasted seeds ofCassia tora L., a new naphthopyrone glycoside was isolated and characterized as 10-[(β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl)oxyl-5-hydroxy-8-methoxy-2-methyl-4H-naphtho
[1,2-b]pyran-4-one(isorubrofusarin gentiobioside). Along with isorubrofusarin gentiobioside, alaternin and adenosine were isolated
and identified. 相似文献
138.
Recombinant human epidermal growth factor (rhEGF), a polypeptide of 53 amino acid residues, is subject to degradation by numerous
enzymes, especially proteases, when it is applied on the skin for the treatment of open wound. Amastatin, aprotinin, bestatin,
EDTA, EGTA, gabexate, gentamicin, leupeptin, and TPCK were investigated for the possible protease inhibitors, which may use
to protect rhEGF from degradation by the enzymes in the skin. Skin homogenates containing protease inhibitors and rhEGF were
incubated at 37°C for 30 minutes. After the reaction was stopped with trifluoroacetic acid, the amount of rhEGF remaining
in the sample was determined with an HPLC method. The percentages of rhEGF degraded, at the skin/PBS ratio of 0.25, in the
mouse, rat, and human skin homogenate were 85%, 70%, and 46%, respectively. The degree of degradation of rhEGF in the cytosolic
fraction was higher than that in the membrane fraction and these enzyme reactions were completed in 30 minutes. Bestatin,
EGTA, and TPCK showed significant inhibitory effects on the degradation of rhEGF in the two fractions (p<0.05), while the
other protease inhibitors had no significant inhibitory effects or, even resulted in deleterious effects. Therefore, the formulation
containing one or several inhibitors among these effective inhibitors would be a promising topical preparation of rhEGF for
the treatment of open wound. 相似文献
139.
The experimental hepatic cirrhosis was induced either by bile duct ligation (BDL) or by pretreatment with dimethylnitrosamine
(DMNA). The pharmacokinetics of theophylline were studied after a single intravenous or a single oral administration. Using
the ultrafiltration method, protein-drug binding experiments were also carried out. The bilirubin level was several-fold increased
by BDL, but not by DMNA treatment. The albumin content was decreased in both cirrhotic groups. The total clearance (Clt, ml/kg/hr)
of theophylline in both hepatic cirrhosis groups significantly decreased and the terminal half-life (t1/2) in the cirrhotic rats was increased about two-fold after intravenous and oral administration. The volume of distribution
at steady state (Vdss, ml/kg) was increased slightly in the cirrhotic groups. Protein binding in BDL (8.67±4.85%) decreased
about four-folds, but in DMNA (73.00±9.85%) similar result, was observed as compared with the control. Increased free fraction
of theophylline did not increase the volume of distribution in BDL. Therefore decreased total body clearance of theophylline
was mainly due to decreased intrinsic clearance of theophylline in the liver. The absolute bioavailability of theophylline
in these experiments was between 63.8 and 72.8%(66.1% in BDL, 63.8% in Sham operated and Control, 72.8% in DMNA). These results
suggest that in the experimental hepatic cirrhosis model, administration route does not affect the disposition of theophylline. 相似文献
140.
We have previously isolated a drug-resistant, [PC3(R)], variant of human prostate PC3 cell line, which showed significant resistance (>10-fold) to adriamycin. No known mechanisms of drug resistance were found; however, resistant cells expressed more bcl2, c-myc, and ms oncogenes compared to the sensitive cells. In this study, we found that buthionine sulfoximine (BSO), an inhibitor of gamma-glutamyl-cysteine synthetase, decreased glutathione levels by 80-90% in both cell lines. BSO treatment down-modulated Ras protein only in PC3(R) cells and caused a 4-fold sensitization of PC3(R) cells to adriamycin without affecting PC3(W) cells. Farnesol treatment also inhibited expression of Ras protein and concomitantly reversed adriamycin resistance in PC3(R) cells, indicating that altered levels of ras expression plays an important role in drug resistance in PC3(R) cells. 相似文献