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131.
An increasing demand for polycistronic vectors that express multiple genes simultaneously has arisen in recent years to obtain an efficient gene therapy. Armed with the knowledge that the expression of transgene in mammalian cells often requires tight control, we constructed in this study a tetracycline-regulated double-gene adeno-associated virus (AAV) vector carrying green and red fluorescent protein genes and expressed it in PC12 cells. When detected by fluorescence microscope and fluorescence-activated cell sorting, gene expression was induced by 44-66-fold and could be reversibly controlled by doxycycline. This double-gene AAV vector may be useful for regulated expression of two genes or a marker to monitor transgene expression.  相似文献   
132.
BACKGROUND: Schneider's first-rank symptoms involve an alienated feature of the sense of one's own mental or physical activity. To clarify the brain morphological basis for the production of these symptoms, volumes of the frontal and medial temporal regions and their clinical correlates were examined in patients with schizophrenia. METHOD: Twenty-two patients with schizophrenia and 44 age- and gender-matched healthy control subjects were included. All patients were in their psychotic episodes with definite Schneiderian symptoms, rated by using the Scale for Assessment of Positive Symptoms. Volumetric measurements of high-resolution magnetic resonance imaging were performed in the prefrontal area, cingulate gyrus, and precentral gyrus, and the medial temporal structures such as the amygdala, hippocampus, and parahippocampal gyrus. RESULTS: Patients had significantly decreased volumes in the cingulate gray matter and the amygdala compared to controls. In the patient group, Schneiderian symptom severity showed significant inverse correlations with volumes of the right posterior cingulate gray matter and of the left anterior parahippocampal gyrus. CONCLUSIONS: Schneiderian symptoms may be associated with morphological abnormalities in the limbic-paralimbic regions such as the cingulate gyrus and parahippocampal gyrus, which possibly serve the self-monitoring function and the coherent storage and reactivation of information.  相似文献   
133.
目的: 观察非选择性一氧化氮合酶(NOS)抑制剂NG-硝基-L-精氨酸(L-NA)对急性肺损伤大鼠肺线粒体功能的影响,并探讨其改善急性肺损伤的作用机制。方法: 将SD大鼠随机分为空白对照组、急性肺损伤组、L-NA治疗组,采用舌静脉注射脂多糖(LPS)复制大鼠急性肺损伤模型,于大鼠急性肺损伤3h后给L-NA治疗3h,断头放血处死大鼠,迅速取出肺脏,匀浆器混匀后,低温差速离心法提取肺线粒体,测定线粒体总ATP酶、超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、总一氧化氮合酶(T-NOS)、诱生型一氧化氮合酶(iNOS)、结构型一氧化氮合酶(cNOS)的活性,以及线粒体肿胀度、膜流动性和线粒体一氧化氮(NO)、丙二醛(MDA)含量;电镜观察大鼠肺线粒体超微结构的改变及治疗药对此改变的影响。结果: 在大鼠内毒素性急性肺损伤后,肺脏组织中线粒体表现为肿胀、膜流动性降低,线粒体中的T-NOS和iNOS活性显著升高,线粒体NO生成明显增加,而cNOS活性无明显变化;线粒体总ATP酶、SOD、GSH-Px活性均明显下降,线粒体MDA含量明显升高。急性肺损伤3h给予L-NA治疗3h,与急性肺损伤组相比,一氧化氮合酶活性有所改变,NO生成显著下降,总ATP酶、SOD、GSH-Px活性均显著升高,MDA含量下降。电镜结果显示内毒素性急性肺损伤后肺脏组织细胞水肿,线粒体肿胀、嵴断裂、溶解、消失;L-NA能改善内毒素性急性肺损伤引起的细胞水肿、线粒体肿胀和空泡化。结论: L-NA能明显抑制急性肺损伤后线粒体一氧化氮合酶活性,减少NO生成,改善线粒体能量供应,增加线粒体抗氧化作用,从而减轻急性肺损伤。  相似文献   
134.
Recent clinical trials showed that bortezomib, a novel proteasome inhibitor, had therapeutic activity in multiple myeloma. However, there was no data about the feasibility of bortezomib in Korean patients. We performed a pilot study of bortezomib in patients with relapsed or refractory myeloma (1.3 mg/m2 twice weekly for 2 week in a 3-week cycle). Seven patients were enrolled. The median age of patients was 59 yr. All patients previously received VAD (vincristine, doxorubicin and dexamethasone) and thalidomide chemotherapy. Three patients previously received alkylator-containing chemotherapy and 4 patients, autologous stem cell transplantation. Bortezomib monotherapy resulted in 3 partial remissions (43%), 3 no changes (43%) and 1 progressive disease (14%). One patient who had no response to bortezomib monotherapy experienced partial remission after addition of dexamethasone to bortezomib. The most common serious toxicity was thrombocytopenia (grade 3/4, 10 of 20 cycles (50%)) and grade 3 peripheral neuropathy was developed in 2 of 20 cycles (10%). Drug-related adverse event led to discontinuation of bortezomib in 1 patient. There was no treatment related mortality. Overall, bortezomib seems to be effective and feasible. Conduction of larger clinical studies on Korean patients is necessary to characterize clinical efficacy and safety of bortezomib more precisely.  相似文献   
135.
A solid-phase blocking ELISA for detection of antibodies to Nipah virus   总被引:4,自引:0,他引:4  
A monoclonal antibody (MAb) based solid-phase blocking ELISA was developed for detection of antibodies to Nipah virus. The ELISA was designed to detect remaining antigens on the plate with anti-Nipah MAb conjugate after the reaction with sample serum, and enabled simple procedure, detection of neutralizing antibody to Nipah virus, and application of samples from different animal species. Forty of 200 swine reference sera examined were positive by the ELISA, of which thirty seven were found positive by serum neutralization test. Sera from a total of 131 fruit bats captured in Malaysia were also tested and all found negative by the both tests. It is considered that the solid-phase blocking ELISA can be used as a screening test for Nipah virus infection followed by the serum neutralization test as confirmatory test.  相似文献   
136.
人MASP1 N端片段原核表达载体的构建及其表达   总被引:1,自引:0,他引:1  
目的:在大肠杆菌中表达人甘露聚糖结合凝集素(MBL)相关丝氨酸蛋白酶1(MASP1)N端片段.方法:采用PCR技术从含人MASP1 cDNA的质粒pGEM-MASP1中扩增MASP1-N端基因片段,将其插入原核表达载体pGEX4T-1,转化BL21(DE3)感受态菌诱导表达MASP1-N端蛋白,通过GSTrap亲合层析柱纯化目的蛋白,以SDS-PAGE和Westernblot进行鉴定,并以ELISA分析了目的蛋白与重组MBL-CLR、重组MBL的结合活性.结果:从pGEM-MASP1中扩增得到约860 bp的基因片段,构建成重组载体经酶切出现约4 900 bp和860 bp片段,测序结果与预期的完全一致.纯化蛋白经SDS-PAGE可见Mr60000蛋白带,该蛋白可与抗GST抗体反应并能与重组人MBL-CLR、重组人MBL蛋白结合.结论:获得了表达人MASP1 N端片段的大肠杆菌菌株和重组人MASP1 N端片段/GST融合蛋白,为MASP1分子的进一步研究提供了条件.  相似文献   
137.
Non-alcoholic duct-destructive chronic pancreatitis is a new entity that differs morphologically and pathogenetically from alcoholic chronic pancreatitis. Some clinical and imaging features of this entity resemble those of pancreatic cancer, and hence most of the reported cases underwent pancreatic resections including an invasive pancreaticoduodenectomy. Recognition of this new entity before a definitive treatment is therefore important to avoid an unnecessary pancreatic resection. Recently, we experienced a case of non-alcoholic duct-destructive chronic pancreatitis in an 80-year-old man presenting with obstructive jaundice and whose radiologic features were characteristic as originally described. Recognition of this new entity before definitive treatment enabled us to manage this patient optimally. In addition, the relation between non-alcoholic duct-destructive chronic pancreatitis and chronic pancreatitis with diffuse irregular narrowing of the main pancreatic duct is discussed.  相似文献   
138.
对不同工艺和条件制备的 7个类金刚石薄膜 (Diamondlikecarbon ,DLC)试样 ,经X光电子能谱 (XPS)碳相成分分析后 ,分别进行了血小板黏附实验、黏附血小板的形貌观察、分类计数和形态指数计算 ,并通过灰色关联分析 ,研究了碳相成分对血小板黏附量、黏附血小板的形态指数的影响。结果显示 :来自全方位离子注入离子束增强沉积工艺的DLC ,其血小板黏附量和形态指数明显小于等离子体化学气相沉积工艺制备的样品 ;在DLC的 5种碳相成分中 ,DLC碳相与血小板黏附量和形态指数的 (负 )关联度远大于其它碳相成分 ,除此之外只有C H和C O碳相与血小板形态指数的 (正 )关联度较大。表明 :(1)DLC碳相对血小板黏附的影响远较其它碳相成分为大 ,增加DLC碳相的含量是优化DLC血液相容性的关键所在 ;(2 )C H和C O碳相对黏附血小板的变形有促进作用 ,须从工艺上抑制其产生或尽可能降低其含量 ;(3)采用全方位离子注入离子束增强沉积工艺有助于改善DLC的血液相容性。这些结论对设计与改进DLC的制备工艺具有重要的指导意义。  相似文献   
139.
脑红蛋白在成年男性生殖系统的表达及意义   总被引:1,自引:0,他引:1  
目的:探讨脑红蛋白(neuroglobin,Ngb)在成年男性生殖系统的表达及其意义。方法:用免疫组织化学SP法观测Ngb在成人男性生殖系统的表达、分布与定位。结果:Ngb在生殖系统内神经节细胞、睾丸间质细胞有较强表达,在睾丸支持细胞、生精细胞、附睾管腔上皮、前列腺腺上皮及精囊黏膜上皮呈弱阳性表达。结论:Ngb在男性生殖系统中分布广泛,其功能值得研究。  相似文献   
140.
目的探讨交感神经递质去甲肾上腺素(NE)对体外培养的肝星状细胞(HSCs)凋亡的影响。方法体外培养HSCs,用四甲基偶氮唑盐(MTT)法检测NE对HSCs增殖的影响;原位杂交凋亡检测(TUNEL)法观察NE及各受体亚型的阻滞剂对HSCs凋亡的影响;流式细胞术检测凋亡率。结果(1)不同浓度NE均促进HSCs增殖,并呈时间依赖性;NE浓度为10μmol/L时促增殖作用最显著;(2)10μmol/L浓度NE作用于HSCs24h,TUNEL和流式细胞术检测HSCs凋亡率均显著低于对照组(P<0.05);(3)加入各肾上腺素受体(AR)阻滞剂后HSCs凋亡率升高,其中α-AR和β2-AR阻滞剂作用最显著。结论交感神经递质NE对体外活化的HSCs具有促增殖作用,并可以抑制HSCs凋亡,主要是通过α-AR和β2-AR起作用的。  相似文献   
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