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931.
BACKGROUND AND OBJECTIVES: The detection of recombinant human erythropoietin (r-HuEPO) abuse by athletes remains problematic. The main aim of this study was to demonstrate that the five indirect markers of altered erythropoiesis identified in our earlier work were reliable evidence of current or recently discontinued r-HuEPO use. A subsidiary aim was to refine weightings of the five markers in the initial model using a much larger data set than in the pilot study. A final aim was to verify that the hematologic response to r-HuEPO did not differ between Caucasian and Asiatic subjects. DESIGN AND METHODS: Recreational athletes resident in Sydney, Australia (Sydney, n = 49; 16 women, 33 men) or Beijing, China (Beijing, n=24; 12 women, 12 men) were randomly assigned to r-HuEPO or placebo groups prior to a 25 day administration phase. Injections of r-HuEPO (or saline) were administered double-blind at a dose of 50 IU/kg three times per week, with oral iron (105 mg) or placebo supplements taken daily by all subjects. Blood profiles were monitored during and for 4 weeks after drug administration for hematocrit (Hct), reticulocyte hematocrit (RetHct), percent macrocytes (%Macro), serum erythropoietin (EPO) and soluble transferrin receptor (sTfr), since we had previously shown that these five variables were indicative of r-HuEPO use. RESULTS. The changes in Hct, RetHct, %Macro, EPO and sTfr in the Sydney trial were qualitatively very similar to the changes noted in our previous administration trial involving recreational athletes of similar genetic origin. Statistical models developed from Fisher's discriminant analysis were able to categorize the user and placebo groups correctly. The same hematologic response was demonstrated in Beijing athletes also administered r-HuEPO. INTERPRETATION AND CONCLUSIONS: This paper confirms that r-HuEPO administration causes a predictable and reproducible hematologic response. These markers are disturbed both during and for several weeks following r-HuEPO administration. This work establishes an indirect blood test which offers a useful means of detecting and deterring r-HuEPO abuse. Ethnicity did not influence the markers identified as being able to detect athletes who abuse r-HuEPO.  相似文献   
932.
933.
可卡因-安非他明调节转录肽基因与2型糖尿病的关联研究   总被引:2,自引:0,他引:2  
Fu M  Cheng H  Chen L  Wu B  Cai M  Xie D  Fu Z 《中华内科杂志》2002,41(12):805-808
目的 探讨可卡因-安非他明调节转录肽(CARTpeptides)基因在国人中的多态性及与2型糖尿病及其临床特征的关系。方法 用聚合酶链反应-单链构象多态(PCR-SSCP)的方法。对无亲缘关系的401例华南地区汉族人CART基因的3个外显子及内含子连接部进行筛查(包括180例糖耐量正常者及221例2型糖尿病患者)并进行测序鉴定。结果 (1)在中国汉族人中存在着CART基因的多态性,为DNA链1457位上的碱基A缺失,位于外显子3的3′端非翻译区。等位基因频率为:A 83.6%,A-16.4%,基因型频率为:A A 68.9%,A A-29.4%,A-A-1.7%。(2)在糖尿病组中CART-A的等位基因频率为:A 84.6%,A-15.4%,基因型频率为:A A 71.9%,A A-25.3%,A-A-2.7%,CART基因A的缺失与糖尿病无明显关联。(3)在糖尿病中有CART基因A缺失的基因型中总胆固醇,高密度脂蛋白胆固醇及低密度脂蛋白胆固醇与对照组有明显差异。结论 中国汉族人中存在着CART基因的多态性。此多态性与糖尿病无明显关联。但涉及糖尿病脂代谢紊乱。  相似文献   
934.
Introduction: Pre-operative evaluation of biliary strictures remains challenging. The dilemma that exists is how to balance the risk of failing to detect malignancy and the potential morbidity caused by unnecessary surgery in patients with benign etiologies. With emerging novel diagnostic modalities, this study aims to assess the efficacy of diagnostic techniques and facilitate a clinical approach to indeterminate biliary strictures.

Areas covered: Conventional imaging modalities are crucial in identifying the location of a stricture and are helpful for choosing further diagnostic modalities. Utilization of endoscopic techniques, including endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic ultrasound (EUS), is key in establishing a diagnosis. The emergence of novel diagnostic modalities, such as fluorescence in-situ hybridization (FISH), peroral cholangioscopy (POC), intraductal endoscopic ultrasound (IDUS) and confocal laser endomicroscopy (CLE), enhance the diagnostic yield in the evaluation of indeterminate biliary strictures.

Expert commentary: More reliable and validated visual criteria for differentiating malignancy from benign biliary conditions, utilizing advanced imaging modalities such as POC and CLE, need to be established. It is of significance to further evaluate these novel diagnostic modalities through ongoing trials and to develop a diagnostic algorithm that reconciles cost-effectiveness with diagnostic accuracy.  相似文献   

935.
Atherosclerosis is a chronic inflammatory disease, which is positively and negatively regulated by T helper (Th) 1 and Th2 lymphocytes, respectively. Recent findings indicate that suppressive oligodeoxynucleotides (ODNs) expressing TTAGGG motifs selectively reduce Th1 cytokine production and have been proven effective at blocking the development of organ-specific autoimmune diseases. In the current research, we hypothesized that suppressive ODNs may alter the development of atherosclerosis. Eight-week-old homozygous ApoE−/− male mice were injected with 300 μg ODNs A151 (TTAGGG) or nonspecific ODNs 1612. Atherosclerotic lesion sizes were dramatically reduced by ODNs A151, but not by nonspecific ODNs. MCP-1 and VCAM-1, which are the key inflammatory factors in atherogenesis, were significantly attenuated by the suppressive ODNs A151. In the splenic lymphocytes, FACS analysis showed ODNs A151 reduced the percentage of IFN-γ-producing Th1 cells and slightly increased the percentage of IL-4-producing Th2 cells, indicating that suppressive ODNs skewed the Th1/Th2 balance toward Th2 inflammation in vivo. Furthermore, ODNs A151 down-regulated the phosphorylation of STAT1 and STAT4 and suppressed up-regulation of T-bet, a signal modulator for Th1, and didn't impact GATA-3 and STAT6, which are associated with a Th2 phenotype. Consistent with this in vivo observation, ELISA analysis demonstrated that ODNs A151 suppressed Th1 cytokines IFN-γ and TNF-α, and augmented Th2 cytokines IL-4 and IL-10 in vitro. This study provides the first experimental evidence that suppressive ODNs inhibit the development of atherosclerosis through inhibition of the STAT1/4 and T-bet pathways, which further modulate the Th1/Th2 balance in vivo.  相似文献   
936.
ABM: This study aims at exploring the distribution of TCM syndromes in CHB patients with HBV pre-core mutation (1896) and the relationship between pre-core mutation and T lymphocytes subgroup, through which to provide objective data on clinical syndrome differentiation of TCM, and further to suggest the therapeutic principle and guide clinical treatment. METHODS: One hundred and forty CHB patients were evenly divided into two study groups, HBV pre-core mutant group and HBV pre-core wild-type group. Besides, 30 healthy blood donors were selected as a healthy control group. HBV-labeled compound, T lymphocytes subgroup, and HBV-DNA pre-core mutant were tested in the study groups. T lymphocytes subgroup were also tested in the control group. All the patients were both diagnosed by syndrome differentiation of TCM and western medicine. RESULTS: The most common syndrome in mutant group was damp-heat combined with blood stasis, and the most common syndrome in the wild-type group was damp-heat stasis in the middle-jiao. There were more cases of medium and severe hepatitis in mutant group than that in wild-type group. The content of CD4+ lymphocytes and CD4+/CD8+ ratio were decreased gradually (healthy control group>wild-type group>mutant group). In the wild-type group, severe and medium CHB patients had considerably lower level of them than mild CHB patients. However, in the mutant group, the opposite result appeared. Meanwhile, the content of HBV-DNA in mutant group was higher than that in wild-type group. CONCLUSION: Damp, heat, toxin and blood stasis were the basic pathogens of CHB, whether pre-core mutant or not. CHB with precore mutant may lead to more severe hepatitis. The decreased content of CD4+ lymphocytes and ratio of CD4+/CD8+ may be taken as one of the indices in confirming the deficiency syndrome of CHB patients with pre-core mutation.  相似文献   
937.
Liver fibrosis in chronic viral hepatitis: An ultrasonographic study   总被引:16,自引:4,他引:16  
AIM: To select valuable ultrasonographic predictors for the evaluation of hepatic inflammation and fibrosis degree in chronic hepatitis, and to study the value of ultrasonography in the evaluation of liver fibrosis and compensated liver cirrhosis in comparison with serology and histology. METHODS: Forty-four ultrasonographic variables were analyzed and screened using color Doppler ultrasound system in 225 patients with chronic viral hepatitis and compensated liver cirrhosis. The valuable ultrasonographic predictors were selected on the basis of a comparison with histopathological findings. The value of ultrasonography and serology in the evaluation of liver fibrosis degree and the diagnosis of compensated liver cirrhosis was also studied and compared. Meanwhile, the influencing factors on ultrasonographic diagnosis of compensated liver cirrhosis were also analyzed. RESULTS: By statistical analysis, the maximum velocity of portal vein and the degree of gall-bladder wall smoothness were selected as the valuable predictors for the inflammation grade (G), while liver surface, hepatic parenchymal echo pattern, and the wall thickness of gall-bladder were selected as the valuable predictors for the fibrosis stage (S). Three S-related independent ultrasonographyic predictors and three routine serum fibrosis markers (HA, HPCIII and CIV) were used to discriminate variables for the comparison of ultrasonography with serology. The diagnostic accuracy of ultrasonography in moderate fibrosis was higher than that of serology (P<0.01), while there were no significant differences in the general diagnostic accuracy of fibrosis as well as between mild and severe fibrosis (P<0.05). There were no significant differences between ultrasonography and serology in the diagnosis of compensated liver cirrhosis. However, the diagnostic accuracy of ultrasonography was higher in inactive liver cirrhosis and lower in active cirrhosis than that of serology (both P<0.05). False positive and false negative results where found when the diagnosis of compensated liver cirrhosis was made by ultrasonography. CONCLUSION: There are different ultrasonographic predictors for the evaluation of hepatic inflammation grade and fibrosis stage of chronic hepatitis. Both ultrasonography and serology have their own advantages and disadvantages in the evaluation of liver fibrosis and compensated liver cirrhosis. Combined application of the two methods is hopeful to improve the diagnostic accuracy.  相似文献   
938.
AIM: Recombined plasmid pETNF-P16 was constructed to investigate its expression properties in esophageal squamous carcinoma cell line EC9706 induced by X-ray irradiation and the feasibility of gene-radiotherapy for esophageal carcinoma. METHODS: Recombined plasmid pETNF-P16 was constructed and transfected into EC9706 cells with lipofectamine. ELISA,Western blot, and immunocytochemistry were performedto determine the expression properties of pETNF-P16 in EC9706 after transfection induced by X-ray irradiation. RESULTS: Eukaryotic expression vector pETNF-P16 was successfully constructed and transfected into EC9706 cells. TNFα expressions were significantly increased in the transfected cells after different doses of X-ray irradiation than in those after 0Gy irradiation (1 192.330-2 026.518 pg/mL,P&lt;0.05-0.01), and the TNFα expressions and P16 were significantly higher 6-48 h after 2 Gy X-ray irradiation (358.963-585.571 pg/mL, P&lt;0.05-0.001). No P16 expression was detected in normal EC9706 cells. However, there was strong expression in the transfected and irradiation groups. CONCLUSION: X-ray irradiation induction could significantly enhance TNFα and P16 expression in EC9706 cells transfected with pETNF-P16 plasmid. These results may provide important experimental data and therapeutic potential for gene-radiotherapy of esophageal carcinoma.  相似文献   
939.
Objectives To find out the efficient dose and safety of simvastatin (Zocor) on the aged patients with coronary artery disease (CAD) for aggressive lipid-lowering treatment. Methods Select 95 aged patients with CAD combined with primary hyperlipemia and give them 20mg/day of simvastatin for treatment. According to the therapeutic target of serum total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) regulate the dosage of simvastatin in follow-up. Observe 12-18 months. Results After treatment, the TC, LDL-C and triglycerides(TG) of the patients reduced by 40%,52% and 26% respectively, while there was no significant change in high-density lipoprotein cholesterol (HDL-C). The apolipoprotein A1 arose by 14.4%, while the apolipoprotein B lowered by 25.0%. The ratio of LDL-C to HDL-C was reduced to 1.96. In the 6^th month, the 12^th month and the 18th month, respectively, 86%, 93% and 95% of the patients took 10mg/day of simvastatin and the result was their TC≤140mg/dL(3.7mmol/L) and LDL-C≤70mg/dL(1.8mmol/L).There was no special side-effect. Multi-factor analysis indicated the age of the patients was a significant factor affecting the adjustment of the dosage of simvastatin.Conclusions The therapeutic result of simvastatin on the aged patients with CAD for aggressive lipid-lowring treatment is definite, safe and the dose is lower as well.  相似文献   
940.
BACKGROUND: The influence of interleukin-10 (IL-10) gene promoter polymorphisms on the mode and sequel of HBeAg seroconversion (a favorable event usually) in patients with chronic Hepatitis B virus (HBV) infection has not been clarified. PATIENTS AND METHODS: IL-10 genotyping and haplotype analyses of 340 HBsAg carriers and 100 volunteers with self-limiting HBV infection from southern China, a high prevalent area of HBV were performed according to the single nucleotide polymorphisms in its promoter (-1,082, -819 and -592) using a competitively differentiated PCR. RESULTS: High-producer genotype (GG at -1,082) or haplotype (GCC) was rarely found in patients from southern China (<1%). Intermediate-producer haplotype (ACC) was closely associated with chronic liver disease (P=0.004); compared with this, low-producer genotype (AA at -592) and haplotype (ATA) were closely associated with asymptomatic carriers (P=0.035 and 0.035). Intermediate-producer genotype (AC at -592) and haplotype (ACC) were closely associated with covert seroconversion of HBeAg (P=0.0086 and 0.0013) and progressive sequel after HBeAg seroconversion (P=0.013 and 0.0008), while, low-producer genotype (AA at -592) and haplotype (ATA) were closely associated with overt seroconversion of HBeAg (P=0.0023 and 0.0061) and silent sequel after HBeAg seroconversion (P=0.0009 and 0.001). CONCLUSIONS: IL-10 gene promoter polymorphisms significantly influence the mode and sequel of HBeAg seroconversion in patients with chronic HBV infection.  相似文献   
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