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891.
BACKGROUND: Mutations in the human SLC4A1 (AE1/band 3) gene are associated with hereditary spherocytic anaemia and with distal renal tubular acidosis (dRTA). The molecular diagnosis of AE1 mutations has been complicated by the absence of highly polymorphic genetic markers, and the pathogenic mechanisms of some dRTA-associated AE1 mutations remain unclear. Here, we characterized a polymorphic dinucleotide repeat close to the human AE1 gene and performed an immunocytochemical study of kidney tissue from a patient with inherited dRTA with a defined AE1 mutation. METHODS: One CA repeat region was identified in a phage P1-derived artificial chromosome (PAC) clone containing most of the human AE1 gene and the upstream flanking region. We determined its heterozygosity value in multiple populations by PCR analysis. Genotyping of one family with dominant dRTA identified the AE1 R589H mutation, and family member genotypes were compared with the CA repeat length. AE1 and vH(+)-ATPase polypeptides in kidney tissue from an AE1 R589H patient were examined by immunocytochemistry for the first time. RESULTS: This CA repeat, previously reported as D17S1183, is approximately 90 kb upstream of the AE1 gene and displayed considerable length polymorphism, with small racial differences, and a heterozygosity value of 0.56. The allele-specific length of this repeat confirmed co-segregation of the AE1 R589H mutation with the disease phenotype in a family with dominant dRTA. Immunostaining of the kidney cortex from one affected member with superimposed chronic pyelonephritis revealed vH(+)-ATPase-positive intercalated cells in which AE1 was undetectable, and proximal tubular epithelial cells with apparently enhanced apical vH(+)-ATPase staining. CONCLUSIONS: The highly polymorphic dinucleotide repeat adjacent to the human AE1 gene may be useful for future studies of disease association and haplotype analysis. Intercalated cells persist in the end-stage kidney of a patient with familial autosomal dominant dRTA associated with the AE1 R589H mutation. The absence of detectable AE1 polypeptide in those intercalated cells supports the genetic prediction that the AE1 R589H mutation indeed causes dominant dRTA.  相似文献   
892.
BACKGROUND: Insulin-like growth factor binding protein-2 (IGFBP-2) is expressed by all human prostate cancer cell lines and dramatically increases in the serum of prostate cancer patients. However, the role of IGFBP-2 in prostatic tumorigenesis is not known. The aim of the present study was to investigate the effects of IGFBP-2 on the proliferation of DU145 human prostate cancer cells in culture. METHODS: Using cell proliferation assays, we examined the effects of exogenously administered and endogenously modulated levels of IGFBP-2 on the proliferation of DU145 cells. RESULT: Cell growth was stimulated by exogenously administered IGFBP-2, but significantly retarded (P < 0.05) by its neutralizing antibody. Overexpression of IGFBP-2 by transfection also stimulated cell growth, which was significantly (P < 0.05) inhibited in transfectants expressing antisense mRNA to IGFBP-2. Furthermore, the proliferation of IGFBP-2 overexpressing cells was significantly dampened by exogenously administered IGFBP-2 antibody. CONCLUSIONS: IGFBP-2 is an autocrine growth factor for DU145 human prostate cancer cells and cell proliferation can be significantly retarded by neutralizing or inhibiting its synthesis. These findings provide a strong rationale for targeting IGFBP-2 in the testing of novel strategies to treat prostate cancer.  相似文献   
893.
894.
发展民营医院的思路和建议   总被引:3,自引:0,他引:3  
管伟立 《中国医院》2003,7(5):50-51
论述了发展民营医院的思路,针对目前发展民营医院存在的困难和问题提出了对政策调整的建议。  相似文献   
895.
Objective To investigate the effect and mechanism by which PPARγ ligand, rosiglitasone, regulates the expression of CD40 and intercellular adhesion molecule 1 (ICAM-1) in the rat peritoneal mesothelial cells (RPMCs) induced by lipopolysaccharide (LPS). Methods RPMCs were harvested from Sprague-Dawley rat peritoneal cavity and maintained under defined in vitro conditions. The cells were randomly divided into groups as follows: medium, LPS (5 mg/L), LPS (5 mg/L)+BAY11-7085(5 μmol/L, NF-κB inhibitor), rosiglitazone (10 μmol/L or 20 μmol/L, peroxisome proliferator-activated receptor γ activator), LPS (5 mg/L)+rosiglitazone (10 μmol/L)+GW9662 (3 μmol/L, peroxisome proliferator-aetivatcd receptor γ antagonist), and LPS (5 mg/L)+vehicle (DMSO 0.2 ml/L). The expressions of CD40 and ICAM-1 RNA in RPMCs were examined by RT-PCR after 3 hour treatment, and the protein expressions of CD40, ICAM-1, p-NF-κB p65 and p-IκBα were examined by Western blot or immunofluorescence after 24 hour treatment. Results Following treatment with LPS, both the expressions of CD40 and ICAM-1 protein in RPMCs were up-regulated significantly (P<0.05), and the phosphoralation of p65 was increased greatly (1.10±0.17 vs 0.55±0.06, P<0.05). BAY11-7085 (5 μmol/L) significantly decreased the protein expression of p-p65 (0.22±0.11 vs 1.10±0.17, P<0.01), CD40 (0.34±0.02 vs 0.50±0.06, P<0.05) and ICAM-1 (0.35±0.16 vs 0.74±0.03, P<0.05). Pretreated with rosiglitazone for 3 h then added with LPS for 1 h, the levels of p-p65, CD40 and ICAM-1 in RPMCs were significantly decreased compared with those of LPS group (0.77±0.08 vs 0.90±0.10, P相似文献   
896.
低位直肠癌的手术治疗:附206例分析   总被引:15,自引:6,他引:9       下载免费PDF全文
目的 探讨低位直肠癌的术式选择及保肛手术的治疗效果。方法 回顾性分析 2 0 6例低位直肠癌病例的临床资料。结果  2 0 6例中行Miles手术 61例 ,各种保肛手术 14 5例。 14 5例保肛手术中术后发生吻合口瘘 16例 ( 11.0 % ,16/ 14 5 ) ,肛门狭窄 13例 ( 9.0 % ,13 / 14 5 )。无手术死亡。术后 5年生存率Miles手术为 62 .3 % ,保肛手术为 67.2 % (P >0 .0 5 )。结论 低位直肠癌的治疗可根据患者情况选用保肛手术或Miles手术。在保证根治的情况下 ,应尽可能选用保肛术。  相似文献   
897.
AIMS: To determine the most appropriate regression models to use when assessing risk factors for severe hypoglycaemia and to investigate the impact of model misspecification and its clinical implications. METHODS: A total of 1229 children with Type 1 diabetes (mean age 11.7 years sd 4.1), of which 605 (49.2%) were males, were studied. Prospective assessment of severe hypoglycaemia (an event leading to loss of consciousness or seizure) was made over the 9-year period, 1992-2001. Patients were seen every 3 months and episodes of hypoglycaemia along with clinical data were recorded. Over 70% of children never experienced a severe hypoglycaemic event. Data were analysed using the Poisson regression, negative binomial, zero-inflated Poisson (ZIP) and zero-inflated negative binomial (ZINB) models. The over-dispersion and likelihood ratio statistics were calculated and the analytical methods compared. RESULTS: The Poisson regression model did not fit the data well. The negative binomial and the zero inflated Poisson and negative binomial models fitted the data better than Poisson. CONCLUSIONS: The commonly used Poisson regression models to analyse hypoglycaemia epidemiology may lead to biased parameter estimates and incorrect determination of risk factors for hypoglycaemia. We recommend the use of the negative binomial or zero inflated models to examine any risk factors associated with severe hypoglycaemia. Careful consideration must be given to the interpretation of hypoglycaemia surveys and their analysis.  相似文献   
898.
Aims The Type 1 diabetes susceptibility locus, IDDM2, has been mapped to a variable number of tandem repeats (VNTR) region 5′ upstream of the insulin (INS) and insulin‐like growth factor (IGF2) genes on chromosome 11p15. The function of the VNTR is uncertain; however, it may influence the thymic expression of the insulin gene and affect the development of immune self‐tolerance. The aim of this study was to investigate whether the INS VNTR region is a Type 1 diabetes‐specific locus or acting as a general autoimmunity gene. Methods We genotyped the INS‐IGF2 VNTR [using the surrogate INS?23 HphI single nucleotide polymorphism (SNP)] in 823 Graves’ disease (GD)/multiple sclerosis (MS) families, 1433 GD/MS patients and 837 healthy control subjects. Results We found no evidence of excess transmission of the allele associated with Type 1 diabetes to individuals affected by GD or MS within the families. Analysis of the case–control dataset showed no genotypic or allelic difference between the two populations. Conclusions These data suggest that the INS‐IGF2 VNTR is acting as a Type 1 diabetes‐specific susceptibility gene rather than as an influence on general autoimmunity.  相似文献   
899.
Hypoxiaisadirectfactorcausinghypoxicpul monaryhypertension (HPH) .hypoxiainduciblefac tor 1α (HIF 1α)isfoundtobethemostcrucialfactorsofarwhichmediatesthecellularresponsetohypoxi a[1] .OurpreviousstudyrevealedthatoverexpressionofHIF 1andendothelin 1(ET 1…  相似文献   
900.
携带人胰岛素样生长因子-1重组腺病毒的构建和鉴定   总被引:6,自引:1,他引:5  
[目的] 采用 Cre-LoxP同源重组系统构建并鉴定携带人胰岛素样生长因子-1( human insulin-like growth factor-1, hIGF-1)目的基因的复制缺陷重组腺病毒,为椎间盘退变的 hIGF-1基因治疗奠定基础.[方法] PCR合成 hIGF-1基因,用 pMD18-T载体克隆 hIGF-1目的基因,酶切、测序并进行 NCBI BLAST相似性在线分析.将 pMD18-T-hIGF-1和 pDNR-1r质粒分别行 EcoRⅠ和 BamHⅠ双酶切, DNA 连接酶连接双酶切产物,转化感受态大肠杆菌 DH5α,合成中间载体 pDNR-hIGF-1,酶切鉴定.Cre-loxP系统介导 pDNR-hIGF-1和 pInt.AV1.SpaT同源重组形成 pInt.AV1.SpaT-hIGF-1重组表达质粒,行 EcoRⅠ酶切鉴定.复苏 293细胞,将 pInt.AV1.SpaT-hIGF-1和 pInt.B.B质粒在 293细胞内进行同源重组成含 hIGF-1基因的复制缺陷重组腺病毒.倒置显微镜观察 293细胞病变样效应( cytopathogenic effect, CPE);透射电镜观察 293细胞中的病毒颗粒;提取细胞裂解液中病毒 DNA, PCR鉴定 hIGF-1目的基因的存在; Western blot 检测 hIGF-1蛋白表达.用半数组织培养感染量 (tissue culture infectious dose 50,TCID50)方法测定重组腺病毒的滴度.[结果]克隆的 hIGF-1目的基因经 NCBI BLAST相似性在线分析证实与 Homo sapiens IGF-1 (GI:19923111)完全相同.pInt.AV1.SpaT-hIGF-1酶切鉴定,出现 5.4 kb和 1 kb两条片段,与理论值完全相符.转染 293细胞 12~ 14 d后,大部分细胞出现肿胀,脱落等细胞病变样效应.PCR鉴定细胞裂解液中含有 hIGF-1目的基因.Western blot 证实重组腺病毒表达 hIGF-1蛋白.第 2代腺病毒的滴度为 80× 106 PFU/mL.[结论]成功构建出含有 hIGF-1目的基因的复制缺陷重组腺病毒.  相似文献   
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