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91.
92.
OBJECTIVE: In a follow-up study, we determined the prevalence, incidence, and natural course of positive antithyroperoxidase antibodies (TPOAbs) and antithyroglobulin antibodies (TgAbs) in the general population and examined the influences of iodine intake. DESIGN: The study was conducted in Panshan, Zhangwu, and Huanghua, regions with mildly deficient, more than adequate, and excessive iodine intake, respectively. Of the 3761 unselected subjects who were enrolled at baseline, 3018 participated in the 5-yr follow-up study. Serum TSH, TPOAb, and TgAb levels were measured. RESULTS: Among subjects in Panshan, Zhangwu, and Huanghua, the prevalence of positive TPOAbs was 11.23, 11.83 and 12.02%, respectively, whereas 11.23, 11.17, and 11.26% of subjects were TgAb positive, respectively. In the older population (> or =45 yr), TgAb-positive individuals were more frequent in Huanghua than Panshan and Zhangwu (P < 0.05). The 5-yr cumulative incidence of positive TPOAb was 2.08, 3.84, and 2.84% in Panshan, Zhangwu, and Huanghua, respectively, whereas 2.91, 3.64, and 5.07% of subjects were TgAb positive, respectively (P < 0.05), corresponding to the increase in iodine intake. Subjects who were TPOAb and/or TgAb positive at baseline developed thyroid dysfunctions more frequently than those without antibodies (14.44 vs. 3.31%, P < 0.01); their incidence of elevated TSH levels was 1.32, 8.46, and 15.38% in Panshan, Zhangwu, and Huanghua, respectively (P < 0.05). CONCLUSIONS: Subjects who were TPOAb and TgAb positive at baseline developed thyroid dysfunctions more frequently than seronegative subjects. High iodine intake was a risk factor for developing hypothyroidism in antibody-positive subjects. A constant exposure to excessive iodine intake increased the incidence of positive TgAb.  相似文献   
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94.
The aims of this study were to examine the expressions of Li-cadherin and Galectin-3 in gastric cancer, and the correlation between Li-cadherin and Galectin-3 in gastric cancer was also analyzed. The present study investigated the expression level of Li-cadherin and Galectin-3 by immunohistochemistry and semiquantitative polymerase chain reaction (PCR), and correlated this with clinicopathologic parameters in 91 cases of gastric cancer. The correlation between expression levels of Li-cadherin and Galectin-3 was analyzed by Spearman correlation analysis. The expression level of Li-cadherin mRNA was correlated to differentiation and lymph node metastasis, and the expression level of Galectin-3 was related to TNM staging, differentiation and lymph node metastasis. On Spearman correlation analysis, a definitive negative correlation was found between the expression levels of Li-cadherin and Galectin-3 in gastric cancerous tissues. We postulate that interaction between Li-cadherin and Galectin-3 may play an important role in the development of gastric cancer.  相似文献   
95.
AIM: To determine the prevalence of nonalcoholic fatty liver in a specific population in Shanghai by an epidemiological survey, and to analyze risk factors of fatty liver.METHODS: Total 4009 administrative officers who denied regular alcohol drinking participated in the survey, and underwent physical examination and laboratory tests. The important parameters were body mass index (BMI), waist hip circumferences ratio (WHR) and levels of serum lipids.Diagnosis of fatty liver was based on established real-time ultrasonographic criteria, the presence of an ultrasonographic pattern consistent with “bright liver”, with evident ultrasonographic contrast between hepatic and renal parenchyma, vessel blurring, and narrowing of the lumen of the hepatic veins. Analysis of data was performed through SPSS for Windows statistical package.RESULTS: The overall prevalence of fatty liver was 12.9%,15.8% in males and 7.5% in females, and the prevalence of fatty liver in males younger than 50 years old, was significantly higher (13.3%) than that of in females (2.7%).But the difference between the sexes became less significant in people older than 50 years (19.1% vs 18.1%). Theprevalence of fatty liver was increased with age; this was markedly presented in females younger than 50 years.Multiple variant regression analysis demonstrated that the prevalence of fatty liver was positively correlated to several risk factors, including male, aging (&gt;50yr), hyperlipidemia,impaired glucose tolerance/diabetes mellitus, hypertension and overweight/obesity.CONCLUSION: There is a high prevalence of nonalcoholic fatty liver among certain population in Shanghai, to which overweight and hyperlipidemia are closely relevant.  相似文献   
96.
Jaagsiekte sheep retrovirus (JSRV) is the causative agent of ovine pulmonary carcinoma, a unique animal model for human bronchioalveolar carcinoma. We previously isolated a JSRV proviral clone and showed that it was both infectious and oncogenic. Thus JSRV is necessary and sufficient for the development of ovine pulmonary carcinoma, but no data are available on the mechanisms of transformation. Inspection of the JSRV genome reveals standard retroviral genes, but no evidence for a viral oncogene. However, an alternate ORF in pol (orf-x) might be a candidate for a transforming gene. We tested whether the JSRV genome might encode a transforming gene by transfecting an expression plasmid for JSRV [pCMVJS21, driven by the cytomegalovirus (CMV) immediate early promoter] into mouse NIH 3T3 cells. Foci of transformed cells appeared in the transfected cultures 2-3 weeks posttransfection; cloned transformants showed anchorage independence for growth, and they expressed JSRV RNA. These results indicate that the JRSV genome contains information with direct transforming potential for NIH 3T3 cells. Transfection of a mutated version of pCMVJS21 in which the orf-x protein was terminated by two stop codons also gave transformed foci. Thus, orf-x was eliminated as the candidate transforming gene. In addition, another derivative of pCMVJS21 (pCMVJS21DeltaGP) in which the gag, pol (and orf-x) coding sequences were deleted also gave transformed foci. These results indicate that the envelope gene carries the transforming potential. This is an unusual example of a native retroviral structural protein with transformation potential.  相似文献   
97.
ABCA1基因多态性与冠心病易感性的关联研究   总被引:13,自引:1,他引:13  
Sun P  Bo XP  Guo DP  Li XY  Hu ZB  Wang J  Li XR  Fan LM  Chen Q 《中华心血管病杂志》2005,33(7):627-630
目的探讨三磷酸腺苷结合盒转运子A1(ATP binding cassette transporter1,ABCA1)基因R219K及M883I单核苷酸多态性(SNP)位点与脂代谢和冠心病(coronary heart disease,CHD)易感性的关系。方法以医院为基础的病例-对照研究。经冠状动脉造影确诊的冠心病病例224例,同一地区正常对照248例。分别以PCR-RFLP和PIRA-PCR对ABCA1第219密码子G→A(Arg219Lys)和第883G→A(Met883Ile)密码子多态进行检测,比较不同基因型与个体血脂水平和冠心病患病风险的关系。结果吸烟、高血压和高血糖是冠心病的独立危险因素。与携带219RR基因型者比较,携带至少1个219K等位基因者(即RK和KK基因型)冠心病患病风险显著降低59%(OR = 0.41,95% CI = 0.27~0.61)。而在883位点,II基因型携带者患冠心病率较低(OR = 0.54,95% CI = 0.26~1.11)。而两位点联合作用分析发现与携带219RR,883MM或883MI基因型者相比较,携带其他组合基因型的个体冠心病患病风险降低61%(OR = 0.39,95% CI = 0.26~0.60)。另外,对照组中携带219K等位基因者血清HDL-C水平显著高于219K非携带者(P = 0.037),提示Arg219Lys位点的多态改变主要通过改变HDL-C水平影响个体冠心病的患病风险。结论ABCA1 R219K可能与中国汉族人群冠心病遗传易感性有关,血清高密度脂蛋白可能是其作用靶点。  相似文献   
98.
AIM: Hepatocellular carcinoma (HCC) with bile duct tumor thrombosis (BDT) is a rare event. The prognosis of this type of patients is very dismal. The aim of this study was to share the experience in the diagnosis and treatment of HCC with BDT, to further improve the prognosis of these patients.METHODS: Thirty-four patients of HCC with BDT received surgical treatment in authors‘ institute from July 1987 to January 2003 were reviewed retrospectively. The experience in the diagnosis and treatment, and the outcome of this type of HCC patients were summarized.RESULTS: Thirty of the 34 patients (88.2%) were positive for alpha-fetoprotein (AFP) (&gt;20 μg/L), and 12 patients (35.3%) were found having obstructive jaundice before operation, 18 cases were suspected of “obstruction of bile duct“ preoperatively. The primary tumors were frequently located at the left medial (13 cases) or right anterior lobe(14 cases). Thirty-one patients received liver resections and removal of BDT, while the other 3 patients received removal of BDT combined with hepatic artery ligation and cannulation(HAL+HAI), or only removal of BDT because their liver function reservation and general condition could not tolerate the primary tumor resection. The 1-year survival rate was 71.4%(20/28). The longest disease-free survival was over 15 years. The intrahepatic tumor recurrence within 1 year after operation was found in 14 patients (14/28, 50.0%).CONCLUSION: Surgical removal of primary tumors and BDT is safe and beneficial to the HCC patients with BDT. Early detection, diagnosis, and surgical treatment are the key points to prolong the survival time of patients.  相似文献   
99.
The effect of the expression of human hepatic lipase (HL) or human apoE on plasma lipoproteins in transgenic rabbits in response to dietary cholesterol was compared with the response of nontransgenic control rabbits. Supplementation of a chow diet with 0.3% cholesterol and 3.0% soybean oil for 10 weeks resulted in markedly increased levels of plasma cholesterol and VLDL and IDL in control rabbits as expected. Expression of either HL or apoE reduced plasma cholesterol response by 75% and 60%, respectively. The HL transgenic rabbits had substantial reductions in medium and small VLDL and IDL fractions but not in larger VLDL. LDL levels were also reduced, with a shift from larger, more buoyant to smaller, denser particles. In contrast, apoE transgenic rabbits had a marked reduction in the levels of large VLDLs, with a selective accumulation of IDLs and large buoyant LDLs. Combined expression of apoE and HL led to dramatic reductions of total cholesterol (85% versus controls) and of total VLDL+IDL+LDL (87% versus controls). HDL subclasses were remodeled by the expression of either transgene and accompanied by a decrease in HDL cholesterol compared with controls. HL expression reduced all subclasses except for HDL2b and HDL2a, and expression of apoE reduced large HDL1 and HDL2b. Extreme HDL reductions (92% versus controls) were observed in the combined HL+apoE transgenic rabbits. These results demonstrate that human HL and apoE have complementary and synergistic functions in plasma cholesterol and lipoprotein metabolism.  相似文献   
100.
Chen Z  Mi L  Xu J  Yu J  Wang X  Jiang J  Xing J  Shang P  Qian A  Li Y  Shaw PX  Wang J  Duan S  Ding J  Fan C  Zhang Y  Yang Y  Yu X  Feng Q  Li B  Yao X  Zhang Z  Li L  Xue X  Zhu P 《The Journal of infectious diseases》2005,191(5):755-760
To identify the function of HAb18G/CD147 in invasion of host cells by severe acute respiratory syndrome (SARS) coronavirus (CoV), we analyzed the protein-protein interaction among HAb18G/CD147, cyclophilin A (CyPA), and SARS-CoV structural proteins by coimmunoprecipitation and surface plasmon resonance analysis. Although none of the SARS-CoV proteins was found to be directly bound to HAb18G/CD147, the nucleocapsid (N) protein of SARS-CoV was bound to CyPA, which interacted with HAb18G/CD147. Further research showed that HAb18G/CD147, a transmembrane molecule, was highly expressed on 293 cells and that CyPA was integrated with SARS-CoV. HAb18G/CD147-antagonistic peptide (AP)-9, an AP of HAb18G/CD147, had a high rate of binding to 293 cells and an inhibitory effect on SARS-CoV. These results show that HAb18G/CD147, mediated by CyPA bound to SARS-CoV N protein, plays a functional role in facilitating invasion of host cells by SARS-CoV. Our findings provide some evidence for the cytologic mechanism of invasion by SARS-CoV and provide a molecular basis for screening anti-SARS drugs.  相似文献   
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