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101.
Lv F  Gao J  Lin J  Liu Z  Xu Y  Ren X  Zhang H  Xu A 《Tissue antigens》2004,64(5):619-620
A novel human leukocyte antigen (HLA)-DQB1 allele, DQB1*020102, was detected in a 28-year-old woman of Han ethnic in Guangzhou, China. Compared with HLA-DQB1*020101 and HLA-DQB1*0202, they differed in only one nucleotide at the position 167 (C to T) of exon 2, which was a highly conserved position. This is a synonymous mutation, which does not cause any change in the amino acid sequence of mature protein.  相似文献   
102.
 Aquaporin-1 is present in the apical and basolateral membranes in proximal tubules and descending limbs of Henlé’s loop. In order to be able to study the routing of Aquaporin-1 and the regulation of Aquaporin-1-mediated transcellular water flow, we stably transfected LLC-PK1 and MDCK-HRS cell lines with an Aquaporin-1 expression construct. LLC-PK1 clone 7 and MDCK clone K integrated two and one copies, respectively, which was reflected in the amount of Aquaporin-1 mRNA expressed in both clones. The Aquaporin-1 protein levels, however, were similar. In both clones, immuno-electronmicroscopy showed extensive labelling of Aquaporin-1 on the basolateral plasma membrane, endosomal vesicles and the apical plasma membrane, including the microvilli. To measure transcellular water permeation, a simple method was applied using phenol-red as a cell-impermeant marker of concentration. In contrast to the native cell lines, both clones revealed a high transcellular osmotic water permeability, which could not be influenced by forskolin add/3-isobutyl-1-methylxanthine (IBMX) or the phorbol ester 12-O-tetradecanoyl 13-acetate (TPA). After glutaraldehyde fixation, it was inhibitable by HgCl2. These results indicate that targeting of Aquaporin-1 to the apical and basolateral plasma membrane is independent of cell type and show for the first time that water flow through a cultured epithelium can be blocked by mercurial compounds. Received: 9 October 1996 / Received after revision: 3 January 1997 / Accepted: 8 January 1997  相似文献   
103.
长期单采浆的慢性丙型肝炎患者肝脏病理学观察   总被引:1,自引:1,他引:1  
Ren J  Wang L  Wang T  Lu J  Lei C  Liu X 《中华病理学杂志》2000,29(6):428-431
目的 观察既往职业献血员慢性丙型肝炎病毒(HCV)感染者肝脏病理学特征。方法 从250名5年以上抗-丙型肝炎病毒(HCV)抗体阳性的献血员中筛选出丙氨酸转氨酶(ALT)异常的丙型肝炎患者66例,对其进行肝穿活检病理检查。其中63例按1995年《病毒性肝炎防治方案(试行)》进行分级分期,对血清病毒含量〉5.0Meq/ml(bDNA)的20例行NS5免疫组织化学ABC染色观察。结果 病变程度大多较轻,炎症活动度G1 4.8%(3/63),G2 63.5%(40/63),G3 28.6%(18/63),G4 2例。纤维化程度S1 60.3%(38/63)、S2 34.9%(22/63),S3 3.2%(2/63),S4 1例。主要病变为汇管区炎症:即胆管损伤(100.0%),淋巴细胞集聚(82.5%),汇管区周围碎屑  相似文献   
104.
Early-onset cataract and Alzheimer's disease occur with high frequency in Down syndrome (trisomy 21), the most common chromosome duplication in human live births. Previously, we used in vivo and lens organ culture models to demonstrate Alzheimer pathophysiology in oxidative stress-related lens degeneration. Currently, well-characterized Alzheimer transgenic mouse models are used to extend these findings. Here, we report on mice carrying a complete copy of a wild-type human AbetaPP (hAbetaPP) gene from the Down syndrome critical region on chromosome 21. hAbetaPP mice produce fiber cell membrane defects similar to those described in human cataracts and increased age-related lens degeneration. hAbetaPP expression and mRNA alternative splicing in human and mouse lens and cornea favor longer, potentially more amyloidogenic forms. Endogenous mouse AbetaPP expression is increased in transgenic lenses, consistent with the cycle of oxidative stress proposed in the mechanism of Alzheimer pathophysiology. Alternative splicing previously designated as neuron-specific occurs in human lens and cornea, and is maintained by hAbetaPP expressed in mouse tissues. These present data implicate AbetaPP in fiber cell formation and in early-onset cataracts in Down syndrome. Finally, our findings provide further support for our hypothesis that Alzheimer pathophysiology contributes to the cataract formation that is increasing in the aging population.  相似文献   
105.
106.
Objective: To investigate the expression of steroidogenic acute regulatory protein (StAR) in macrophages and the effects of inflammatory cytokines on StAR expression. Methods: The macrophages isolated from ApoE knockout mice and C57BL/6J mice and RAW264.7 cells (a cell line from mouse macrophage. ATCC Number: TIB-71TM) were cultured in DMEM containing 10% fetal bovine serum. RAW264.7 cells were treated with different inflammatory cytokines (TNF-α, IFN-γ and TGF-β1) and 8-Br-cAMP, a cAMP analog. RT-PCR and Western blot analysis were applied to evaluate the effects of inflammatory cytokines on StAR expression. Results: RT-PCR and Western blot analysis demonstrated the expression of StAR in the macrophages isolated from ApoE knockout mice, C57BL/6J mice and RAW264.7 cells. Proinflammatory cytokines TNF-α and IFN-γ significantly decreased StAR mRNA and protein levels in RAW264.7 cells. The inhibition was dose- and time-dependent. In contrast, anti-inflammatory cytokine TGF-β1 increased StAR mRNA and protein levels. At 1:15 molecular ratio, TGF-β1 blocked the down-regulation of StAR expression mediated by TNF-α. cAMP also induced StAR expression in RAW264.7 cells. When the cells were co-treated with 8-Br-cAMP and TNF-α, 8-Br-cAMP failed to induce StAR expression. Conclusion: Our results provide interesting evidence that inflammatory cytokines regulate StAR expression in macrophages. Received 12 August 2006; returned for revision 28 September 2006; returned for final revision 28 May 2007; accepted by M. Katori 22 June 2007  相似文献   
107.
目的:探讨高压氧治疗重度颅脑损伤的疗效。方法:重度颅脑损伤患者35例为治疗组,20例为对照组,观察高压的氧治疗前后临床、脑电地形图的变化及预后。结果:治疗组临床(GCS)、脑电地形图及预后经高压氧治疗后均明显改善,而对照组改善不明显。结论:高压氧能够明显改善重度颅脑损伤患者的临床,脑电地形图及预后。  相似文献   
108.
With an incidence of approximately 1 in 500 male newborns, the 47,XXY genotype is one the most common sex chromosome anomalies. It is also the most frequent genetic cause of human infertility. Some non-mosaic 47,XXY patients have sperm production which allows infertility treatment to be offered by ICSI. Therefore, the risk of transmitting a chromosome anomaly to the next generation is an important problem in reproductive genetic counselling of these patients. Here, we report on a twin pregnancy where two karyotypically normal neonates 46,XX and 46,XY were born after the use of ICSI in assisted reproduction of a patient with a non-mosaic 47,XXY syndrome. To date, only 38 evolving pregnancies including the present cases, have been reported after ICSI using sperm from non-mosaic 47,XXY patients. Although these data are scarce, they suggest that the risk of chromosome anomaly in the offspring of these patients is low; hence, their reproductive genetic counselling can be reassuring, and management of the pregnancy can proceed with caution.  相似文献   
109.
243例健康人血红细胞悬浮液射频介电特性的研究   总被引:8,自引:0,他引:8  
本文应用同轴传输线反射法建立的细胞悬浮液介电测量系统,测量了243例健康人(男120,女123名)血红细胞悬浮液在1~500MHz频率范围的介电常数和电导率。结果表明不同性别和不同血型之间的红细胞悬浮液的介电参数无显著差异。将19~80岁之间的受试者按10岁年龄间隔分成六个组,探讨年龄差别对介电参数的影响;发现50岁左右是人红细胞介电参数有显著差异的临界年龄,49岁后三个高年龄组的介电参数显著地低于49岁前的三个低年龄组的数值(P<0.05)。本文的结果证明年龄对人血红细胞的介电参数有明确的影响。  相似文献   
110.
Attention deficit hyperactivity disorder (ADHD) is a prevalent disorder in children. The etiology of this disease is not clear. Genetics studies have suggested the involvement of the dopamine DRD-4 receptor gene and dopamine transporter gene (DAT1). Clinical studies have shown that monoamine oxidase-B (MAO-B) inhibitors are effective in the treatment of ADHD. These findings suggest that monoamine oxidase (MAO) genes might be involved in the origin of ADHD. In the present work, the DXS7 locus of chromosome X, which is closely linked to MAO genes, was selected as a marker to study the possible association between ADHD and MAO genes in the Chinese population. Haplotype-based haplotype relative risk (HHRR) and the transmission disequilibrium test (TDT) methods were employed to analyze the association and the linkage disequilibrium, respectively. Significant association (X(2) = 15.86; 1 df; P < 0.001) and linkage (X(2) = 14.88; 1 df; P < 0.001) were detected between the 157-bp allele of the DXS7 locus and the DSM-III-R-diagnosed ADHD (N = 72) in trios composed of father, mother, and affected offspring. The data suggested that ADHD was associated and in linkage with DXS7 locus.  相似文献   
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