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101.
W. S. Hong Y. I. Min H. T. Kim Y. B. Cho K. H. Kim D. K. Kim 《Journal of Korean medical science》1995,10(4):269-274
In an attempt to develop a new anticancer platinum complex with greater or equivalent antitumor activity but reduced side effects compared with cisplatin (CDDP), a series of new platinum complexes having a glycolate leaving ligand was synthesized. Among them, five complexes were selected for further development on the basis of adequate water solubility, low nephrotoxicity and high antitumor activity in a murine system. The chemosensitivity of these five complexes was examined in MTT assay against two human pulmonary adenocarcinoma cell lines, PC-9 and PC-14, and two human stomach adenocarcinoma cell lines, MKN-45 and KATO III. Their IC50 and relative antitumor activity (RAA) values were compared with those of CDDP and 254-S, a second-generation platinum complex with a glycolate leaving ligand under phase III clinical trial. The lowest mean IC50 value was observed in CDDP, followed by SKI 2034R and SKI 2033R. In this study, the antitumor activity was evaluated in terms of RAA values and SKI 2034R showed the highest RAA value. The order of RAA values was SKI 2034R > CDDP > SKI 2032R > SKI 2033R > SKI 2030R > SKI 2029R > 254-S. Based on the RAA order, we have recommended SKI 2034R as the most promising candidate for further development of a clinically useful platinum complex. 相似文献
102.
103.
The platelet interactivity phenotype of Streptococcus sanguis influences the course of experimental endocarditis. 下载免费PDF全文
M C Herzberg G D MacFarlane K Gong N N Armstrong A R Witt P R Erickson M W Meyer 《Infection and immunity》1992,60(11):4809-4818
A strain of Streptococcus sanguis that induced rabbit platelets to aggregate in vitro (Agg+ phenotype) was hypothesized to be a more virulent pathogen than an Agg- strain in experimental endocarditis in rabbits. A left ventricular catheter was implanted, and then an Agg+ or Agg- strain was inoculated intravenously. Vegetations formed on the aortic semilunar valves but were unaffected by the duration of implantation of the catheter. Vegetations enlarged by accumulating platelets and their mass increased directly with the duration of endocarditis. Inoculation of the Agg+ strain consistently caused endocarditis with significantly larger vegetations, a more severe clinical course (including febrile episodes, hematological changes, and signs of myocardial ischemia), more gross lesions in major organs, and greater mortality than inoculation with the Agg- strain, saline, or the Agg+ strain pretreated with monospecific rabbit immunoglobulin G or Fab fragments against its platelet aggregation-associated protein (PAAP; class II). In experimental endocarditis, PAAP expressed by Agg+ S. sanguis appeared to be an important virulence factor. 相似文献
104.
环丙沙星与氧氟沙星注射液治疗细菌性感染的疗效观察 总被引:3,自引:0,他引:3
以乳酸环丙沙星(CPLX)注射液和氧氟沙星(OFLX)注射液随机分组治疗各种细菌性感染40例及42例,并以注射用头孢噻肟钠(CTX)治疗49例作对照。三组平均年龄、体重、疗程及病情程度相比无显著性差异,具可比性。病种分布以消化道感染最多,共81例,占总数的61.8%。三组131例病人细菌阳性率为94.7%。一疗程CPLX组、OFLX组、CTX组治愈率分别为87.2%、83.3%、71.4%,有效率 相似文献
105.
经内镜胆管引流术在肝门部恶性胆管梗阻中的应用及其评价 总被引:9,自引:2,他引:7
肝门部恶性肿瘤手术切除率极低,临床处理十分棘手。作者采用内镜胆管引流术治疗此类肿瘤288例次(肝门部胆管癌184例、胆囊癌23例、肝细胞癌侵犯肝门部胆管47例、其他转移性肿瘤34例),其中行内镜鼻胆管引流162例次、塑料内置管引流80例次、放置可膨式金属胆道支架46例、4例患者接受同期双内置管引流。引流总有效率为67.0%,其中效果满意者43.1%;40例患者术后1个月内发生胆管炎,发生率为13.8%,3例死亡;长期随访病例的平均存活期5.3个月。我们观察到治疗的效果与Bismuth分型有密切关系,如果全肝40%以上的胆系得到引流,黄疸有望消退;左、右两侧胆管同时引流可扩大引流范围,提高疗效;应合理选择三种内镜胆管引流方法并适时灵活转换才能获得满意的疗效。结论:对于肝门部肿瘤,内镜胆管引流术是一种安全有效的治疗手段,可作为首选的姑息性治疗。 相似文献
106.
96名镍作业工人测定结果:非特异酯酶阳性细胞百分率(ANAE+%)为76.8%±8.0%,T细胞亚群CD2、CD4、CD8阳性细胞百分率(CD+2%、CD+4%、CD+8%)及CD+4/CD+8比值分别为65.6%±10.5%、56.3%±12.1%、34.3%±8.2%和1.76±0.6;酵母多糖刺激的外周血多形核白细胞化学发光(PMN-CL)本底和峰值分别为48±23和3073±684CPS/106PMN;血清硒和丙二醛含量分别为1.22±0.23和4.76±0.88μmol/L。与非镍作业的地区对照组比较,T细胞CD+8%增高,CD+4/CD+8比值下降,化学发光的本底值降低,峰值增加,血清Se含量下降,丙二醛含量升高。分析镍作业工人工龄与后三项指标变化的关系,工龄大于20年与小于10年有统计学上明显差别。这些观察指标为镍作业人员医学观察增加新的监护指标提供依据。 相似文献
107.
赖型钩体flaB2与VR1012中的CpG基序分析 总被引:3,自引:0,他引:3
目的:对问号赖型钩端螺旋体(赖型钩体)DNA疫苗[包括内鞭毛蛋白基因(flaB2)和质粒DNA表达载体(VR1012)]的CpG基序(CpG motifs)进行分析,为DNA疫苗免疫机制的阐明和提高DNA疫苗的效能奠定基础。方法:以flaB2与VR1012构建重组DNA的免疫原,对flaB2及VR1012全核苷酸序列进行计算机分析(分类、计数和定位)。结果:CpG的“C”的侧翼为两个嘌呤,“G”的侧翼为两个嘧啶,在flaB2中共3个,分别为GACGCT,GACGTC和GACGCC;在VR1012中共11个,分别为GACGTC1个,GACGCT2个,GACGCC1个,GACGTT1个,GGCGTT2个,GGCGCT2个,GGCGCC1个,AACGCT1个,其中特别重要的TGACGTCA4个和TAACGCCA有1个,位于5'端456-463;509-516;592-599;778-785和486-493;4个TGACGTCA和1个TAACGCCA均位于5'端且相对集中。结论:赖型钩体flaB2与VR1012构成的DNA疫苗含有TGACGTCA等CpG,这些基序又称免疫刺激序列,构成了DNA疫苗中的佐剂。 相似文献
108.
J. Gong B. D. Rawal C. F. Högman MD G. N. Vyas B. Nilsson and I. Gustafsson 《Vox sanguinis》1994,66(3):166-170
We report studies on the complement sensitivity of four strains of Yersinia enterocolitica , serotypes O:3, O:9, O:5,27, and O:20, isolated from blood units involved in transfusion fatalities. Complement in fresh CPD plasma killed Y. enterocolitica within 4 h at 22°C in 100% of the experiments. The bactericidal action was serotype and complement activation pathway dependent. Both classic and alternate pathways seemed to be active, but the latter to a lesser degree. When the classic pathway was blocked by chelation of Ca2+ no complete killing was obtained. Complement did not enhance or condition Yersinia for leucocyte filter retention. Direct removal of Yersinia by filtration was also related to serotype; all strains were reduced by filtration in heat-inactivated plasma, and all except serotype O:5,27 were reduced in Ca2+ -chelated plasma. Our findings may explain why plasma products and platelet concentrates are rarely involved in Yersinia sepsis related to transfusion. 相似文献
109.
采用ELISA法检测104例各类型乙型肝炎(乙肝)患者的血清前-S2抗原(Pre-S2Ag)及其抗体(Pre-S2Ab),结果表明,Pre-S2Ag的出现与HBsAg、HBeAg、HBcAb呈显著相关性(P值均<0.005),主要见于乙肝急性期及慢性乙肝患者,说明病毒复制活跃、传染性强。而Pre-S2Ab阳性仅见于急性乙肝恢复期。 相似文献
110.
The relationship between induction of hepatic metallothionein (MT) synthesis and lipid peroxidation by free radical production following an injection of menadione or carbon tetrachloride (CCl4) in mice was studied. The hepatic concentration of MT was increased by menadione significantly at 25 mg/kg or higher. A significant increase in thiobarbituric acid (TBA) value, indicative of lipid peroxidation, was observed in the liver at menadione doses of 62.5 mg/kg or higher. Both the MT and the TBA value in the liver were significantly increased at the low dose of CCl4. The concentration of MT was increased significantly 4-8 hr after administrations of these compounds. The increase of TBA value over time was similar to that of MT concentration after administration of CCl4, but not after administration of menadione. The MT concentration in the menadione group was higher than that in the CCl4 group, and the TBA level in the menadione group was lower than that in the CCl4 group. Pretreatment with vitamin E caused a significant reduction in the TBA value, but did not affect the MT level in the liver. The concentration of MT did not significantly correlate with the TBA value in either the menadione or the CCl4 group. Pretreatment with phenobarbital, which promotes free radical production, did not influence induction of MT synthesis following an injection of menadione or CCl4. Neither L-buthionine sulfoximine nor 2-cyclo-hexen-1-one, which decreases hepatic glutathione, influenced the induction of MT by menadione. These data suggest that induction of MT synthesis by menadione or CCl4 is independent of free radical production in the liver. 相似文献