龙参颗粒的质量标准研究

目的:为龙参颗粒提供方便可行的质量控制方法。方法:采用薄层色谱法进行定性鉴别;用HPLC法对成品中苦参碱进行含量测定。结果:薄层层析可成功鉴别出当归和黄芪药材;Hypersil NH_2,色谱柱(4.6mm×200mm,5μm);柱温:25℃;流动相:乙腈-0.02mol/L磷酸二氢钠(82:18);流速:1mL/min;检测波长:215nm。加样回样率为97.70％,RSD为1.56％。结论:本实验方法基本可控制龙参颗粒的质量。     

HP感染与c—myc,c—erbB—2蛋白在胃粘膜病变中的表达

为了探讨幽门螺旋杆菌（HeliclbacterPylori，HP）感染与胃癌发生间的关系，我们采用免疫组化法对158例胃粘膜标本进行癌基因c－myc、c－erbB－2蛋白检测、其中胃癌、不典型增生及肠上皮化生各40例，正常对照38例。结果发现，c－myc蛋白在正常胃组织中无表过，c－erbB－2蛋白阳性表达7／38例。两种基因蛋白在不典型增生、肠上皮化生及胃癌中的阳性表达显著高于对照组（P＜0．01～0．05）。应用Giemsa法对上述各组胃粘膜同步进行HP测定，发现正常对照组中的HP阳性检出显著低于不典型增生及肠上皮化生（P＜0．025），而与胃癌组无明显统计学差异（P＞0．05）。联合检测HP与癌基因蛋白发现HP感染与其表达呈正相关。提示HP感染与胃癌发生有一定关系。     

Inhibition of growth and induction of apoptosis in human cancer cell lines by tea polyphenols

In order to study the biological activities of tea preparations and purified tea polyphenols, their growth inhibitory effects were investigated using four human cancer cell lines. Growth inhibition was measured by [3H]thymidine incorporation after 48 h of treatment. The green tea catechins (-)-epigallocatechin-3-gallate (EGCG) and (-)- epigallocatechin (EGC) displayed strong growth inhibitory effects against lung tumor cell lines H661 and H1299, with estimated IC50 values of 22 microM, but were less effective against lung cancer cell line H441 and colon cancer cell line HT-29 with IC50 values 2- to 3- fold higher. (-)-Epicatechin-3-gallate, had lower activities, and (-)- epicatechin was even less effective. Preparations of green tea polyphenols and theaflavins had higher activities than extracts of green tea and decaffeinated green tea. The results suggest that the growth inhibitory activity of tea extracts is caused by the activities of different tea polyphenols. Exposure of H661 cells to 30 microM EGCG, EGC or theaflavins for 24 h led to the induction of apoptosis as determined by an annexin V apoptosis assay, showing apoptosis indices of 23, 26 and 8%, respectively; with 100 microM of these compounds, the apoptosis indices were 82, 76 and 78%, respectively. Incubation of H661 cells with EGCG also induced a dose-dependent formation of H2O2. Addition of H2O2 to H661 cells caused apoptosis in a manner similar to that caused by EGCG. The EGCG-induced apoptosis in H661 cells was completely inhibited by exogenously added catalase (50 units/ml). These results suggest that tea polyphenol-induced production of H2O2 may mediate apoptosis and that this may contribute to the growth inhibitory activities of tea polyphenols in vitro.      

Characterization of xenobiotic-metabolizing enzymes and nitrosamine metabolism in the human esophagus

Esophageal cancer has been associated with tobacco smoking, and nitrosamines are possible causative agents for this cancer. The present study investigated the metabolism of the tobacco carcinogens N'- nitrosonornicotine (NNN), 4-(methylnitrosamino)-1-(3-pyridyl)-1- butanone (NNK), and N-nitrosodimethylamine (NDMA), as well as the presence of xenobiotic-metabolizing enzymes in human esophageal tissues from individuals in the United States and Huixian, Henan Province, China (a high-risk area for esophageal cancer). All esophageal microsomal samples activated NNN and the metabolic rate was 2-fold higher in the esophageal samples from China than the USA. All microsomal samples activated NDMA. However, most of the microsomal samples did not activate NNK. Troleandomycin (an inhibitor of cytochrome P450 3A) decreased the formation of NNN-derived keto acid by 20-26% in the esophageal microsomes. The activities for NADPH: cytochrome c reductase, ethoxycoumarin O-deethylase, NAD(P)H: quinone oxidoreductase and glutathione S-transferase were present in the esophageal samples. Coumarin 7-hydroxylase (a representative activity for P450 2A6) activity was not detected in the esophageal microsomal samples. The activities for nitrosamine metabolism and xenobiotic- metabolizing enzymes were decreased (by 30-50%) in the squamous cell carcinomas compared with their corresponding non-cancerous mucosa. The presence of activation and detoxification enzymes in the esophagus may play an important role in determining the susceptibility of the esophagus to the carcinogenic effect of nitrosamines. Our results suggest that P450s 3A4 and 2E1 are involved in the activation of NNN and NDMA, respectively, in the human esophagus.      

Quantitative determination of ursolic acid in Herba cynomorii by ultraviolet spectrophotometry]

Ursolic acid was isolated form Herba Cynomorii by thin layer chromatography and was quantitatively determined by ultraviolet spectrophotometry. The results indicate that the content of ursolic acid is 0.78%. The average recovery rate of ursolic acid is 97.4%, RSD = 0.45% (n = 4).     

反义核酸抑制胃癌细胞Bcl-2表达

本文采用分子克隆技术成功地构建了反义核酸表达载体pDOR-Bcl-2 cDNA.以脂质体介导法将重组反义核酸表达载体转染受体细胞SGC7901,并经C418筛选,从2×10~5细胞中筛选出大约150个抗性克隆,转导率大于1‰,随机挑选2个克隆继续筛选与扩增培养,获得了1株稳定的抗性细胞,从而建立了Bcl-2表达阻断的胃癌细胞株,我们命名为7901anBcl-2 cells.通过Southern印迹法、Northern印迹法、Western印迹法检测显示,转导株与非转导株均有Bcl-2 cDNA的表达,但转导株Bcl-2 mRNA及蛋白的表达明显低于非转导株.说明在胃癌细胞中Bcl-2基因处于高表达状态,通过真核表达载体介导的转染,反义Bcl-2可成功地导入胃癌细胞,并有效地阻断Bcl-2表达.     

p53蛋白在肺癌的表达及临床意义

目的　研究 p5 3蛋白在肺癌的表达情况及临床意义。方法　应用 SABC免疫组化技术 ,研究 6 9例各型肺癌组织 p5 3蛋白表达。结果　p5 3蛋白表达的总阳性率为 5 9.4% ,其中鳞癌5 6 .7% ,腺癌 73.7% ,小细胞癌 6 1.5 % ,大细胞癌 40 %。支气管粘膜上皮异型增生和鳞癌有相同的p5 3蛋白表达 ,而正常组织细胞中未见 p5 3蛋白表达。结论　提示 p5 3蛋白表达可能是支气管粘膜上皮密变的早期改变 ,p5 3蛋白是肺癌细胞的重要标志物。     

眩晕康治疗椎-基底动脉缺血性眩晕90例临床研究

目的:观察眩晕康治疗椎-基底动脉缺血性眩晕的临床疗效。方法:选择椎-基底动脉缺血性眩晕患者120例,随机分为2组。治疗组90例,以眩晕康治疗;对照组30例,以尼莫通(现改名为尼膜同)治疗。观察临床疗效、治疗前后症状积分、椎-基底动脉血平均流速、血液流变学指标及血浆内皮素(ET)、一氧化氮(NO)、血浆脂质过氧化物(LPO)、超氧化物歧化酶(SOD)等指标变化情况。结果:总有效率治疗组为96.7％,对照组为83.3％,2组比较,差异有显著性意义(P<0.05),提示治疗组疗效优于对照组。2组治疗前后症状总积分比较,治疗组优于对照组(P<0.05)。而且治疗组椎-基底动脉血平均流速、血液流变学指标、ET、NO、LPO、SOD等指标的改善均优于对照组(P<0.05)。结论:眩晕康是治疗椎-基底动脉缺血性眩晕的有效中成药。     

放疗联合肝动脉化疗栓塞治疗肝癌的研究进展

对于不能手术的原发性肝癌患者，放射治疗配合肝动脉栓塞化疗（TACE）的疗效明显好于单纯放疗或单纯化疗，治疗并发症的发生率和程度可以接受，大多数患者可以耐受。放疗配合动脉栓塞化疗是治疗不能手术的原发性肝癌患者的非常有发展前途的治疗方法。现综述这二种治疗方法的技术特点、疗效和协同作用研究的现状及最新进展。