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81.
林敏  张仁利  高世同 《热带医学杂志》2004,4(3):253-254,267
目的 体外扩增间日疟原虫深圳株红内期小亚单位核糖体核糖核酸编码基因(SSUrDNA)片段,研究其结构与功能。方法 设计一对特异性引物,采用聚合酶链反应(PCR)从间日疟原虫患者血样中扩增出间日疟原虫SSUrDNA片段,以PUC19质粒T载体构建重组子导入大肠杆菌JM109;阳性克隆双酶切鉴定后,双脱氧末端终止法测定序列。结果 间日疟原虫SSUrDNA扩增片段大小为341bp;阳性克隆双酶切及PCR扩增均得到预期大小的片段;序列测定插入片段为341bp,与Sal I株顺序相比,仅在第151位处缺失一个碱基C。结论 成功克隆了间日疟原虫SSUrDNA片段.该序列在间日疟原虫虫株间高度保守。  相似文献   
82.
Cytosine deaminases (CDs) in bacteria andfungi are found to deaminate prodrug 5 - FC intocytotoxic agent 5 - FU .Yeast CD (YCD) is clonedfrom Saccharomyces cerevisiae.It has been shownpreviously that YCD was more efficient inconversing5 - FC than bacterial CD(b CD) [1-3 ] .As anovel suicide gene therapy system,YCD/ 5 - Fcsystem may be promising in cancer therapy andprevention of graft versus host disease.In thepresent study,we established a P388/ DBA murineleukemia model by infusin…  相似文献   
83.
Phospholipidosis (PLD) is characterized by an intracellular accumulation of phospholipids in lysosomes and the concurrent development of concentric lamellar bodies. Recently, H. Sawada et al. (2005, Toxicol. Sci. 83, 282-292) identified 17 genes as potential biomarkers of PLD in HepG2 cells. The present study was undertaken to determine if this set of genes measured by quantitative PCR could be validated in the same cell line. The objective was also to investigate the dose-response relationship to further validate the assay and to select the concentrations to use for screening activities. In a first experiment (one concentration tested), out of the 17 genes, the best gene biomarkers of PLD (i.e., 11 genes) were selected for practical screening reasons. Based on these genes, 91.6% (i.e., 11 of 12) of the compounds known to induce PLD were identified as positive and all the negative compounds (i.e., five of five) were also confirmed. When the data obtained in the first experiment were compared to the data by Sawada et al., (2005) the coefficient of correlation calculated was slightly higher than 75%. In the second experiment (26 compounds [all 17 compounds from the first experiment plus 9 other compounds] tested at a minimum of three concentrations), 93.3% (14/15) of the compounds known to induce PLD were identified as such and all the negative controls (six compounds) were also confirmed. Three compounds likely to induce PLD were identified as positive in our assay. Finally, two compounds for which no data are available were also tested. When both experiments 1 and 2 were compared, the coefficient of correlation for 16 compounds tested at the same concentrations reached 87.7%. In conclusion, the present study further confirms the utility of gene expression in HepG2 cells to identify a potential to induce PLD. Finally, based on the data presented, researchers are encouraged to use a range of minimum three concentrations (e.g., 12.5, 25, and 50 microM) to screen for PLD in the human HepG2 cell line.  相似文献   
84.
85.
目的了解ret/PTC基因突变与超声、病理诊断在甲状腺乳头状癌诊断中的关系。方法术前超声检查,并在超声引导下细针穿刺,活体取材进行病理诊断和逆转录聚合酶链(RT-PCR)方法检测ret/PTC基因突变。结果在34例超声与病理诊断的甲状腺乳头状癌(PTC)患者中,16例分子生物学检测发现ret/PTC基因突变(47%),其中8例为PTC-1基因突变(50%),2例PTC-2基因突变(12.5%),2例PCT-3基因突变(12.5%),3例PTC-1和PTC-2突变同时存在(18.75%),1例PTC-1和PTC-3突变同时存在(6.25%)。结论ret/PTC基因重组突变可存在于散发的甲状腺乳头状癌中,主要表现PTC-1型。应用超声引导下细针穿刺与甲状腺乳头状癌基因突变的检测相结合是早期诊断甲状腺乳头状癌的有效方法。  相似文献   
86.
OBJECTIVES: Vesicoureteral reflux (VUR) is the most common congenital urinary tract anomaly. This disease can pose a major threat to the kidneys as twenty percent of patients with endstage renal disease are reported to have VUR. Although genetic studies for uroplakin III (UPIII) have been reported recently, no study has focused on UPIII gene expression in VUR patients. We describe here the up-regulation of UPIII mRNA in exfoliated urinary cells from primary VUR patients. METHODS: A real-time RT-PCR for UPIII mRNA was performed on exfoliated urothelial cells from 18 primary VUR and 38 control samples. UPIII mRNA copies were calculated for each sample. The statistical differences were assessed by the Mann-Whitney U test. Receiver operator characteristic curves were constructed for analysis of the diagnostic values. RESULTS: UPIII mRNA was found to be up-regulated to a greater extent in VUR than in control exfoliated urinary cells (mean +/- SE: 497.0 +/- 178.5 copies vs. 69.0 +/- 10.0 copies, respectively, P < 0.001). In evaluating the measurement of urinary UPIII mRNA as a screening test for VUR, the sensitivity was 77.8% and the specificity was 76.3% by the best diagnostic cutoff point. CONCLUSIONS: This is the first report demonstrating up-regulation of UPIII in mRNA levels in VUR patients. We submit that the quantitative measurement of urinary UPIII mRNA has a potential of developing into the first non-invasive screening test for VUR.  相似文献   
87.
The rising incidence of hepatocellular carcinoma (HCC) in western countries, along with the poor prognosis offered by present-day treatment modalities, makes novel therapies for this disease necessary. Oncolytic herpes simplex viruses (HSV) are replication-competent viruses that are highly effective in the treatment of a wide variety of experimental models of human malignancies. This study seeks to investigate the effectiveness of oncolytic herpes viruses in the treatment of primary HCC cell lines. Sixteen commercially available human HCC cell lines were studied. G207 is an attenuated, replication-competent, oncolytic HSV engineered to selectively replicate within cancer cells. Cell lines were tested for viral sensitivity to G207 and their ability to support viral replication using standard cytotoxicity and viral replication assays. Eleven of 16 cell lines were moderately to highly sensitive to G207 viral oncolysis. HCC cell lines additionally demonstrated the ability to support viral replication in vitro with as high as 800-fold amplification of the administered viral dose observed. G207 is cytotoxic to, and efficiently replicates within, HCC cell lines in vitro. From these data, we suggest that oncolytic HSV therapy may have a role in the treatment of HCC, and in vivo studies are warranted. Presented in part at the 2005 American Hepato-Pancreato-Biliary Association Congress, Hollywood, Florida, April 14–17, 2005. Supported by grants R01CA75461 and R01CA72632 from the National Institutes of Health, and by grant MBC-99366 from the American Cancer Society (Yuman Fong).  相似文献   
88.
Objective To evaluate preliminarily the effect of HSV - tk/GCV system on gallhladder carcinoma cells in vitro.Methods Recombinant retroviral vector PLtkSN containing tk suicide gene was transfacted into gallbladder carcinoma cells, mediated by LipofectAMINETM 2000 liposome, and the growth - inhibiting rotes of GBC, SD/tk cells in the different GCV concentrations were measured by MTr methods; GBC - SD cells were mixed in the different proportions, and death rotes of the mixed cells treated with GCV were detected to verify by stander effect. Resuts GCV could lead GBC - SD/tk cells to significant death, and there was striking difference compared with the control cells (p〈0.01). When the concentration of GCV was 1,10, 50,100,500ug/ml, the killing rate of GBC - SD/tk cells was respecfively 6.8%, 2.5.2%, 54.5%, 66.3%, 89.3%, indicating dose - dependent phenomenon; With GBC - SD/tk cells in the proportion of 0, 10%, 20% ,50%, 70%, 100%, the killing rate of the mixed cells treated with GCV was 0, 19.7%, 40.3%, 77.7%, 88.0%, 93.5%, respectively. It was apparent that bystander effect was observed in the experiment. Condusion HSV - tk/GCV system could be a potential tool for the treatment of carcinoma.  相似文献   
89.
目的探讨自发性高血压大鼠颈动脉中抑癌基因P53和原癌基因c-jun、c-fos、c-myc mRNA的表达.方法用逆转录聚合酶链式反应检测两种基因的表达水平.正常雄性大鼠作为对照组.结果 SHR颈动脉中,抑癌基因P53和原癌基因c-jun、c-fos、c-myc均有高表达,较WKY差异有显著性(P<0.05).结论自发性高血压大鼠颈动脉组织中抑癌基因P53和原癌基因c-jun、c-fos、c-myc均有高表达,癌基因的活化可能与自发性高血压大鼠颈动脉血管重构有关.  相似文献   
90.
Human tumor–infiltrating lymphocytes (TILs) derived from pleural or ascitic fluid were incubated with recombinant interleukin 2 and transfected with human tumor necrosis factor (TNF) a gene by the lipofection procedure. The resulting TILs secreted significant amounts of TNF in the culture supernatant and exhibited cytotoxicity against established cell lines, such as K562 and Daudi, and autologous tumor cells. The TNF gene–transfected TILs exhibited an augmented killing of autologous tumor cells.  相似文献   
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