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961.
目的研究1例散发多发性外生性骨疣患者的基因突变情况,确定其致病基因。方法采用聚合酶链反应结合DNA直接测序法检测EXT1以及EXT2基因的突变热点区域;并应用错配引物PCR扩增引入酶切位点结合限制性片段长度多态性方法检测和鉴定突变。结果经测序证实在患者EXT1基因的第7内含子3’剪接位点上游26bp处发现一杂合突变,此杂合突变不存在于其表型正常的父母双亲中,是一个新生突变;错配引物扩增与限制性片段长度多态性分析结果表明在150名家系外正常对照者中没有此突变。结论EXT1基因1633-26(C→A)突变可能是导致这个患者发生多发性外生性骨疣的致病突变。 相似文献
962.
Bahram Dalir-Naghadeh Siamak Asri-Rezaei Naser Alidady 《Comparative clinical pathology》2006,15(3):149-153
Odds ratio was used to evaluate relationship between sepsis in cattle less than 1 year old and mastitis in cows and erythrocyte glutathione peroxides (GSH-PX) activity as an indicator of selenium status. Data were from 178 blood samples collected from referred cases to Urmia University, Veterinary Teaching Hospital. Low activity of GSH-PX was significantly associated with higher odds of developing sepsis (P=0.005) in young cattle and mastitis (P=0.044) in adult cows. The odds ratios for the low activity of GSH-PX on incidence of sepsis and mastitis were 4.74 and 3.95, respectively. Selenium deficiency was associated with sepsis in young cattle and mastitis in cows, i.e., cattle with low activity of erythrocyte GSH-PX were at increased risk of sepsis and mastitis. 相似文献
963.
目的研究转录因子HESR1在血管新生中的作用。方法检测内皮细胞激活状态HESR1表达的影响,克隆HESR1基因,转染到HUVEC,绿色荧光和PCR观察HESR1在内皮细胞的表达,流式细胞仪检测它对血管内皮细胞增殖,boyden小室检测对细胞迁移的影响,建体外二维血管模型,观察HESR1对血管形成的影响。结果内皮细胞激活状态HESR1的表达下降,HESR1基因能抑制内皮细胞的增殖和迁移,减少血管新生。结论HESR1基因通过抑制内皮细胞的增殖和迁移,使内皮细胞从激活状态转入安静状态,减少血管的形成,维持血管的稳定状态。 相似文献
964.
Paramyxoviruses of type 1 (PMV-l) isolated from pigeons were genetically analyzed. A part of the fusion and the matrix protein genes were amplified and sequenced, Typical amino acid sequences associated with virulence were determined at the fusion protein cleavage site in all PMV-1 isolates. All Slovene pigeon PMV-1 strains share high amino acid sequence similarity with other pigeon strains. In the phylogenetic tree, they are clustered together with pigeon PMV-1 isolates with moderate pathogenicity. Phylogenetic analysis obtained from the fusion and the matrix protein gene alignments showed the same branching order. Viruses circulating among pigeons were found to form quite unique lineage of virulent NDV strains. 相似文献
965.
We studied the kinetics of thietazole distribution in the liver, brain, kidneys, spleen, heart, skeletal muscles, lungs, adipose
tissue, and testicles after single and repeated administration of this drug. Single and repeated administration of thietazole
was followed by elimination of this drug from the blood into organs and tissues. After repeated administration, thietazole
was selectively accumulated in the spleen.
__________
Translated from Byulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 145, No. 5, pp. 555–557, May, 2008 相似文献
966.
Eleven single nucleotide polymorphisms and one triple nucleotide insertion of the human TGF-β III receptor gene 总被引:1,自引:0,他引:1
Zippert R Bässler A Holmer SR Hengstenberg C Schunkert H 《Journal of human genetics》2000,45(4):250-253
We found 11 single nucleotide polymorphisms and one triple nucleotide insertion in the cDNA of the human transforming growth
factor β (TGF-β) III receptor gene (TGFBR3) located on 1p33–p32, encoding betaglycan, a component of the TGF-β receptor system. Inside the 5′ untranslated region (UTR),
a G→A polymorphism was identified at position 311. In the open reading frame (ORF), a non-conservative T→C polymorphism was
identified at position 392, and three conservative polymorphisms were found at positions 563 (G→A), 1548 (G→A), and 2370 (C→T).
A triple nucleotide insertion (GCA) was identified at position 1419. Inside the 3′ UTR, six polymorphisms were identified:
four G→A, at positions 2918, 3055, 3098, and 3355; one T→A, at position 3183; and one G→C, at position 3966. In addition to
these changes, some divergences from the published sequence were observed in all 12 chromosomes tested. These included, in
the ORF, an additional C after position 555, two additional G after position 563, and an additional T after position 1388.
No T was found at position 1394. The alterations translate to a changed amino acid sequence. Inside the 3′ UTR, additional
discrepancies were identified. The discovered changes and polymorphisms may be useful for further genetic studies of TGFBR3 receptor deficiencies.
Received: December 22, 1999 / Accepted: February 25, 2000 相似文献
967.
Yu WH Zhao KW Ryazantsev S Rozengurt N Neufeld EF 《Molecular genetics and metabolism》2000,71(4):573-580
The Sanfilippo syndrome type B (MPS III B) is an autosomal recessive disease caused by deficiency of alpha-N-acetylglucosaminidase (EC 3. 2.1.50), one of the lysosomal enzymes required for the degradation of heparan sulfate. The disease is characterized by profound neurodegeneration but relatively mild somatic manifestations, and is usually fatal in the second decade. A mouse model had been generated by disruption of the Naglu gene in order to facilitate the study of pathogenesis and the development of therapy for this currently untreatable disease. Recombinant human alpha-N-acetylglucosaminidase (rhNAGLU) was prepared from secretions of Lec1 mutant Chinese hamster ovary cells. The enzyme, which has only unphosphorylated high-mannose carbohydrate chains, was endocytosed by mouse peritoneal macrophages via mannose receptors, with half-maximal uptake at ca. 10(-7) M. When administered intravenously to 3 month-old mice, rhNAGLU was taken up avidly by liver and spleen but marginally if at all by thymus, lung, kidney, heart, and brain (in order of diminishing uptake). The half-life of the enzyme was 2.5 days in liver and spleen. Immunohistochemistry and electron microscopy showed that only macrophages were involved in enzyme uptake and correction in these two organs, yet the storage of glycosaminoglycan was reduced to almost normal levels. The results show that the macrophage-targeted rhNAGLU can substantially reduce the body burden of glycosaminoglycan storage in the mouse model of Sanfilippo syndrome III B. 相似文献
968.
Malamachanahalli B. Vasudevachari Norman P. Salzman Daniel R. Woll Christopher Mast Katharina W. Uffelman Gary Toedter David Hoefheinz Julie A. Metcalf H. Clifford Lane 《Journal of clinical immunology》1993,13(3):185-192
The presence of p24 core antigen in the serum of individuals with human acquired immunodeficiency syndrome has been used as one of the important prognostic markers of HIV-1 infection and also as an end point in evaluating antiviral drugs and vaccines. Unfortunately the majority of p24 antigen present in serum exists as an antigenantibody complex and is not detected with the commercial kits currently available to measure p24 antigen. In this study, we report a simple procedure utilizing treatment of serum samples with glycine buffer (pH 1.85) to dissociate antigen-antibody complexes prior to assaying for p24 antigen. A 300% increase in the number of p24-reactive samples and a 3- to 12-fold increase in the quantity of antigen detected were observed when samples were pretreated with 1.5M glycine buffer (pH 1.85) for 1 hr. Glycine treatment of samples did not result in nonspecific positive tests and samples previously shown to be reactive remained positive. In reconstruction experiments the release of antigen was found to be inversely proportional to the amount of p24 antibody present in the serum. The percentage of HIV-1-infected patients positive for p24 antigen was clearly a function of CD4 count. Forty-nine percent of patients with more than 500 CD4 cells and 100% of patients with less than 200 CD4 were p24 positive. The improved sensitivity for detection of p24 provided by this procedure enhances our understanding of the pathogenesis of AIDS by showing that the majority of patients with HIV-1 infection is p24 positive and facilitates the analysis of data obtained in clinical trials involving anti-HIV compounds. 相似文献
969.
A Orozco C E Contreras P Sánchez O Meilijson N E Bianco 《Journal of immunological methods》1983,59(2):237-243
A C1q solid phase microassay was designed for the rapid detection of circulating immune complexes. Its level of sensitivity is comparable to that of the Raji cell and greater than the C1q binding assay; furthermore, it is faster and low in cost. These conditions make it more practical and applicable in the clinical setting. 相似文献
970.
The density dependence of the maximum expiratory flow-volume curve, functional residual capacity (FRC), and specific airway conductance (SGaw) were determined before and during bronchial provocation with ragweed extract in 27 subjects with ragweed hypersensitivity and a history of either bronchial asthma (16 subjects) or allergic rhinitis (11 subjects). Mean baseline SGaw was significantly lower while mean volume of isoflow (Visov) and FrC were significantly higher in subjects with bronchial asthma. During antigen challenge, 10 of 16 subjects with bronchial asthma (63%) and five of 11 subjects with allergic rhinitis (45%) showed a greater than 35% decrease in SGaw ("reactors"): mean relative decreases in SGaw from baseline were 46% and 53%, respectively. The remaining subjects showed a less than 35% decrease in SGaw ("nonreactors") with mean relative decreases of 9% (allergic asthma) and 6% (allergic rhinitis). Mean Visov increased in all subjects with bronchial asthma and in eight of 11 subjects with allergic rhinitis. A significant increase in FRC (6%) was seen only in the "reactors" with bronchial asthma. Following antigen challenge, the beta adrenergic agonist, isoetharine, increased SGaw and decreased Visov. We conclude that in asymptomatic subjects with ragweed hypersensitivity, (1) central and peripheral airway function is more abnormal in subjects with bronchial asthma than in subjects with allergic rhinitis, (2) subjects of both groups show quantitatively and qualitatively comparable airway responses during antigen challenge with a decrease in SGaw or an increase in Visov, possibly representing increase in central and/or peripheral airflow resistance, respectively, (3) Visov may be a more sensitive indicator of airway response to antigen challenge than SGaw, and (4) the bronchodilator effects of a beta adrenergic agonist on antigen-induced bronchospasm are similar in both groups. 相似文献