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991.
Cao XS  Gu WY  Chen ZX  Hu SY  He J  Cen JN 《中华内科杂志》2007,46(4):277-279
目的探讨慢性粒细胞白血病(CML)患者骨髓细胞中Wilms瘤抑癌基因(WT1)的表达水平及其临床意义。方法建立实时定量RT-PCR方法,采用Light Cycler PCR仪检测了46例(109份骨髓细胞cDNA标本)CML患者和23例非白血病患者骨髓细胞中WT1及内参β胆色原脱氢酶(GAPDH)的表达水平,以WT1N=(WT1拷贝数/GAPDH拷贝数)×10^4计算WT1表达水平。结果23份CML加速期与22份CML急变期患者骨髓细胞中WT1N的中位表达水平分别为103.71和129.44,明显高于64份CML慢性期和对照组(分别为3.44和1.47,P〈0.01),对照组与CML慢性期之间WT1基因表达差异无统计学意义;CML加速期与急变期之间WT1基因表达差异也无统计学意义(P〈0.05)。WT1基因表达水平与BCR/ABL融合基因表达水平具有一定的相关性。对其中7例CML患者行异基因骨髓移植前后动态检测WT1上升可提示白血病复发。结论CML患者加速急变期骨髓细胞中WT1基因表达升高,具有参考意义。  相似文献   
992.
The influence of hepatitis B virus (HBV) gene heterogeneity on the failure of HBV vaccination in eastern China remains unknown. Here, we assigned 78 hepatitis B surface antigen (HBsAg)-carrier mothers to two groups: 41 mothers from whom transmission of HBV to their children was successfully prevented and 37 mothers whose children were HBsAg positive 1 year after HBV vaccination. The DNA loads in mothers of the failure group (4.17E + 07 copies/ml) were significantly higher than those in the success group (8.40E + 06 copies/ml). However, no difference was found in the S gene mutation rate and genotypes between the groups. Interestingly, Thr123Ala and Gly145Arg were observed only in failure-group mothers, whereas Thr126Asn, Thr126Ser, Thr143Asn, Asp144Gly, and Asp144Ala were seen in the success group. Thus, high viral load is an important risk factor for HBV vaccination failure, which is correlated with the positions of mutations in the S gene, but not with mutant frequencies or genotypes. She-Lan Liu and Ying Dong have contributed equally to this work.  相似文献   
993.
J. Li  B. Sun  Y. Huang  X. Lin  D. Zhao  G. Tan  J. Wu  H. Zhao  L. Cao  N. Zhong 《Allergy》2009,64(7):1083-1092
Background: The prevalence of sensitization in patients with asthma and rhinitis in mainland China remains unclear. Objective: Our aim was to estimate the prevalence of allergy in patients with respiratory allergic diseases such as asthma and/or rhinitis attending respiratory clinics within mainland China. The study also investigated regional and annual differences in the prevalence and pattern of sensitization among the patients in China. Method: A cross‐sectional survey was performed in 6304 patients suffering from asthma and/or rhinitis in 17 cities from 4 regions of China. Patients completed a standardized questionnaire asking for the presence of respiratory and allergic symptoms. They also underwent skin prick tests with 13 common aeroallergens. Results: Among the 6304 patients, 4545 (72.1%) had at least one positive skin prick reaction. The overall prevalence of positive skin prick responses was 59.0% for Dermatophagoides farinae, 57.6% for Dermatophagoides pteronyssinus, 40.7% for Blomia tropicalis, 16.1% for American cockroach, 14.0% for dog, 11.5% for Blatella germanica, 11.3% for Artemisia vulgaris, 10.3% for cat, 6.5% for Ambrosia artemisifolia, 6.3% for mixed mould I, 4.4% for mixed mould IV, 3.5% for mixed grass pollen and 2.2% for mixed tree pollen. Sensitizations to common allergens varied widely between geographical areas and demonstrated unique pattern in patients by stratification with age groups, with asthma and/or rhinitis. Severity of rhinitis and asthma was significantly correlated with skin index of reactivity to Artemisia vulgaris, Ambrosia artemisifolia and to D. pteronyssinus, D. farinae and Blomia tropicalis respectively (P < 0.001). Positive reactivity to the tested allergens and concomitant reactivity to multiple allergens including to house dust mites and Blomia tropicalis was markedly increased in patients with both asthma and rhinitis. Conclusion: House dust mites were the most prevalent allergens in patients with asthma and/or rhinitis in China. There were significant differences in patterns of sensitizations in patients from different geographical areas, age groups as well as asthma and/or rhinitis.  相似文献   
994.
Poly(ethylene glycol) diacrylate (PEGDA) hydrogel scaffolds were engineered to promote contractile smooth muscle cell (SMC) phenotype via controlled release of heparin. The scaffold design was evaluated by quantifying the effects of free heparin on SMC phenotype, engineering hydrogels to provide controlled release of heparin, and synthesizing cell-adhesive, heparin releasing hydrogels to promote contractile SMC phenotype. Heparin inhibited SMC proliferation and up-regulated expression of contractile SMC phenotype markers, including smooth muscle α-actin, calponin, and SM-22α, in a dose-dependent fashion (6 μg/ml to 3.2 mg/ml). Heparin release from PEGDA hydrogels was controlled by altering PEGDA molecular weight (MW 1000–6000) and concentration at polymerization (10–30% w/w), yielding release profiles ranging from hours to weeks in duration. Heparin released from PEGDA gels, formulated for optimized heparin loading and release kinetics (30% w/w PEGDA, MW 3000), stimulated SMCs to up-regulate contractile marker mRNA. A cell-instructive scaffold construct was prepared by polymerizing a thin hydrogel film, with pendant RGD peptides for cell attachment, over the optimized hydrogel depots. SMCs seeded on these constructs had elevated levels of contractile marker mRNA after 3 d of culture compared with SMCs on control constructs. These results indicate that RGD-modified, heparin releasing PEGDA gels can act as cell-instructive scaffolds that promote contractile SMC phenotype.  相似文献   
995.
To elucidate the molecular mechanisms of spinal fusion with different graft materials during an anterior lumbar interbody fusion, we examined the gene-expression profiles after implantation of equine bone protein extract, rhBMP-2 and autograft using microarray technology and data analysis, including hierarchical clustering, self-organizing maps (SOM), KEGG pathway and Biological process GO analyses in a porcine model. The results suggest that equine bone protein extract exhibited a more similar expression pattern with autograft than that of rhBMP-2. rhBMP-2 recruits progenitor cells, proliferation and differentiation possibly by inducing various factors including PGHS-2, IFGBP-2, VEGF and chemokines and then leads to preferable membranous ossification and bone remodeling. Conversely, equine bone protein extract results in endochondral ossification via upregulation of cartilage-related genes. Ossification by inducing direct osteoblastic differentiation and obviating the cartilaginous intermediate phases may increase spinal fusion rate.  相似文献   
996.
目的: 探讨伊贝沙坦联合舒洛地特对大鼠糖尿病肾脏协同保护作用及其机制。 方法:将雄性SD大鼠随机分为5组:正常对照组(C)、糖尿病模型组(D)、伊贝沙坦组(I)、舒洛地特组(S)及伊贝沙坦与舒洛地特联合给药组(I+S),糖尿病大鼠模型用STZ诱导。 12周后观察尿白蛋白的排泄率(UAER),做肾组织病理检查,测定肾组织中MDA含量与SOD、CAT、GSH-PX的活性变化。RT-PCR法检测肾组织中ICAM-1 mRNA的表达。EMSA 检测NF-κB的活性。结果:各给药组均可抑制糖尿病大鼠UAER的增加及肾组织病理结构损害,联合组优于单独给药组。对肾组织MDA含量增加及抗氧化应激的SOD、CAT、GSH-PX活性降低的改善作用,联合组优于单给药组。各给药组均可抑制肾组织NF-κB活性,以联合组最明显;糖尿病大鼠肾组织ICAM-1 mRNA表达明显高于对照组,各给药组肾组织ICAM-1 mRNA表达明显低于模型组,其中以联合组最明显。 结论:伊贝沙坦与舒洛地特联合用药对糖尿病肾脏保护作用优于任一单种用药,其机制可能部分是通过对糖尿病肾组织氧化应激、NF-κB 活性及 ICAM-1 mRNA表达协同抑制而实现的。  相似文献   
997.
大肠癌中Bmi-1的表达及其临床病理意义   总被引:3,自引:1,他引:2       下载免费PDF全文
目的:研究大肠肿瘤组织中Bmi-1蛋白表达情况及其与大肠癌临床病理特征及预后的关系,并探讨Bmi-1蛋白在大肠癌中的表达与Ki67蛋白表达的关系。方法:采用免疫组织化学方法分别检测Bmi-1蛋白在60例大肠癌、30例大肠腺瘤及20例正常大肠黏膜组织3组中的表达情况及其与大肠癌临床病理特征及患者生存率的关系,并探讨大肠癌中Bmi-1 蛋白表达与Ki67蛋白的相关性。应用SPSS13.0软件包对结果进行统计学分析。结果:Bmi-1蛋白在大肠癌、大肠腺瘤及正常大肠黏膜组织中的表达率分别为25.0%、6.7%、0%, Bmi-1蛋白在大肠癌中表达明显高于腺瘤组及正常组(P<0.05),而在腺瘤组及正常组中的表达差异无显著(P>0.05);Bmi-1蛋白高表达与有无远处转移及TNM分期密切相关(P<0.05),而与患者性别、年龄、肿瘤大小、分布部位、分化程度、组织类型及淋巴结转移等临床病理特征无关(P>0.05);Kaplan-Meier生存分析显示Bmi-1蛋白高表达患者生存率明显低于低表达患者(P<0.05);大肠癌中Bmi-1蛋白高表达与Ki67蛋白表达无相关关系(P>0.05)。结论:Bmi-1蛋白表达与大肠癌的发生、转移及预后关系密切,可作为评估患者侵润转移及预后的参考指标。  相似文献   
998.
瘦素对缺氧复氧L02肝细胞凋亡及Fas/FasL表达的影响   总被引:1,自引:1,他引:0  
目的: 观察瘦素(leptin)对缺氧复氧人正常肝细胞(L02)凋亡的影响。方法: 将L02细胞分别分为正常对照组、单纯缺氧12 h复氧组(IR组)和缺氧12 h复氧加不同浓度的瘦素(分别为100 μg/L、200 μg/L、400 μg/L、800 μg/L 和1 600 μg/L)干预组, 以流式细胞仪分析、DNA缺口末端标记 (TUNEL) 试验、荧光定量 PCR 等方法观察leptin 对L02肝细胞凋亡、Fas/FasL mRNA表达的影响。结果: (1)与正常对照组相比,IR组细胞凋亡率和TUNEL细胞阳性率增加(P<0.01),加用不同浓度瘦素干预组的细胞凋亡率和TUNEL细胞阳性率与IR组相比明显下降(P<0.05);(2)与正常对照组相比,IR组 L02 细胞中Fas/FasL mRNA表达明显上调(P<0.01);加用不同浓度瘦素干预组与IR组相比,Fas/FasL mRNA表达下降,以400 μg/L瘦素作用明显,结果有显著差异(P<0.05)。结论: 瘦素能减轻缺氧复氧培养L02肝细胞的凋亡,其机制可能与其下调细胞中Fas/FasL mRNA的表达有关。  相似文献   
999.
溶血磷脂酸与血管平滑肌细胞表型转化   总被引:3,自引:2,他引:1  
2003年人类基因组计划的完成开辟了人类遗传学、人类病理学等研究领域的新时代,然而近年来解析人类基因组意义过程中遇到一系列的难题使人们认识到DNA序列本身并不能解释所有关于遗传信息传递、人类疾病生物学基础等问题.随着研究的深入,人们逐渐认识到不仅蛋白编码序列,而且非编码序列、表观遗传机制等也是影响遗传信息传递、疾病发生等过程中的重要因素.  相似文献   
1000.
ObjectiveDepression is a common psychiatric problem in patients with type 2 diabetes (DM2). A common view is that the burden of having DM2 contributes to the development of depression in DM2. Aim of the present study was to compare the levels of diabetes-specific emotional problems of DM2 patients with diagnosed depression with those with a subclinical form of depression and those without depression.MethodsA cross-sectional study was conducted in 101 DM2 patients (51 men and 50 women, mean age = 63,17; SD = 10,74) who completed a standardized, structured psychiatric diagnostic interview (MINI), the Beck Depression Inventory, the Hamilton Depression Rating Scale as well as the Problem Areas in Diabetes (PAID) scale (a 20-item measure, with an overall scale measuring diabetes-related emotional distress and four subscales [negative emotions, treatment-related problems, food-related problems, lack of social support]).ResultsA depression diagnosis was made in 35% (n = 35) of the participants, 24% (n = 24) had a subclinical form of depression, 42% (n = 42) were not diagnosed with any kind of depressive disorder. Diabetes-specific emotional problems were most common in DM2 patients with a depressive disorder (significantly highest PAID score: 39) compared to patients with subclinical depression or no depression. In the group of non-depressed patients, only 14% agreed to have four or more (somewhat) serious diabetes-specific problems. In those with subclinical depression, this percentage was 42% and in those with a depressive disorder 49% (P < 0.001).ConclusionsDiabetes-related emotional problems are particularly common among DM2 patients with comorbid clinical depression and to a lesser extent in patients with subclinical depression, compared to non-depressed DM2 patients. Male diabetes patients with a depressive disorder are particularly vulnerable to develop high levels of diabetes-specific emotional distress. Major differences between the three groups mainly concern the diabetes-specific problems connected with the illness.  相似文献   
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