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991.
目的:评价双盘封堵器介入治疗继发孔型房间隔缺损(ASD)的临床疗效及安全性。方法:在X线透视和经食道超声心动图(TEE;13岁以下儿童经胸超声心动图,TTE)监视下,采用经皮穿刺放置封堵器方法治疗继发孔型ASD16例,术后立刻、24h、1月、3月进行TEE或TTE和X线胸片检查,以评价其疗效。结果:本组16例封堵器置入均获成功。其中9例术后胸闷症状立即消失,第2天即能下床活动,无特殊不适主诉;另7例症状任2周后逐渐好转。1例术后仍有微量分流,3个月后分流才消失;术后1个月有8例右房及右室内径较术前缩小。14例术后3个月TTE显示ASD无残余分流,封堵器位置良好;另2例失访。结论:经皮封堵治疗继发孔型ASD,是一种有效的介入治疗方法,具有安全、有效、操作简便,成功率高的特点。  相似文献   
992.
采用小鼠神经母细胞瘤细胞无血清培养,建立神经细胞老化实验研究模型。以流式细胞光度术观察精氨酸加压素(AVP)对老化过程中实验性神经细胞的细胞周期和细胞总蛋白的影响。结果发现AVP可产生延缓细胞老化的细胞周期和细胞总蛋白的变化。提示AVP通过使细胞周期、DNA和细胞总蛋白等发生变化来发挥其延缓实验性神经细胞老化的作用。  相似文献   
993.
The kinetics of the polymerization of isoprene with the heterogeneous rare earth catalyst system isopropoxyneodymium dichloride/triethylaluminium (Nd(OPri)Cl2-AlEt3) was examined in a specially designed dilatometer. The rate of polymerization is expressed as Rp ≈ ?d[M]/dt = k[Nd]1.40 [M]. The main kinetical parameters such as the concentration of active propagating chain, the efficiency of lanthanide catalyst used (ELCU), the absolute rate constant of propagation as well as the average life time of growing chains, were determined at 30°C, 40°C, 45°C and 50°C.  相似文献   
994.
The expression of Fas antigen at the surface of renal cell carcinoma and the susceptibility to Fas-mediated lysis by a tumor specific CTL clone were investigated. Renal cell carcinoma cell lines expressed Fas antigen and were susceptible to apoptosis mediated by antibodies to Fas/APO1. Using RT-PCR, we further showed that these cell lines expressed mRNA for Fas deleted transmembrane region, corresponding to a soluble form of Fas/APO-1. To investigate the role of the Fas/FasL pathway in the cytotoxic response against RCC cells, we analyzed the induction of Fas-L on a tumor specific T cell clone (CTL 8C2), previously generated against one RCC cell line. Fas-L expression on CTL 8C2 was detected by RT-PCR after stimulation with autologous tumor cells. However, the cytotoxic activity of CTL 8C2 was completely abolished when EGTA was added, suggesting that the cytolysis was mainly mediated by a Ca++-dependent pathway, perforin/granzyme-based.  相似文献   
995.
研究了成纤维细胞介导的IL-3基因疗法,IL-6基因疗法以两者联合后对造血系统的影响。结果发现,单用IL-基因疗法的小鼠白细胞总数,中性粒细胞,骨髓CFU-GM,CFU-MK等显著上升,但血小板上升程度经,单用IL-6基因疗法的小鼠血小板,中性粒细胞,骨髓CFU-GM,CFU-MK上晚为显著。  相似文献   
996.
以51例晚期肿瘤患者作为研究对象,对其不同来源的肿瘤浸润淋巴细胞(TIL)进行治疗研究,发现肿瘤组织来源的TIL其有效率及一年生存率明显高于胸腹水及转移淋巴结的TAL;其中肿瘤组织的TIL,胸腹水、转移淋巴结的TAL有效率分别为80.9%、40.0%、46.6%;三者治疗肿瘤患者的一年生存率分别为81.0%、46.7%、60.0%;另外发现胸腹水TAL对实质性肿块治疗疗效较低,为40%,其中静脉滴  相似文献   
997.
实验用构建的正向连入人IFN-γcDNA片段的重组表达载体pMAMneo-γ-IFN,以Lipo-fectin介导法将重组载体转染入胃癌细胞7901中,挑选出G418抗性克隆,地塞米松诱导其分泌IFtI-γ经活性测定筛选出高分泌IFN-γ的细胞株RPM7901-7(1725IU/ml),Southernblot证实IFN-γcDNA确已导入该细胞株中。体外培养过程中,RpM7901细胞与转染了对照质粒pMAMneo的细胞pM7901及野生型7901细胞在形态,生长能力等方面无明显差别,而经地塞米松诱导的RpM7901细胞则与之有显著差异。裸鼠体内接种显示,经诱导的RpM7901细胞在致瘤性上显著低于野生型7901细胞及pM7901细胞。经基因转移后可高分泌IFN-γ的肿瘤细胞为肿瘤的基因治疗提供了资料。  相似文献   
998.
J Cai  X Liu  J Wang  W Tian 《Human immunology》2012,73(10):1023-1030
In this study, we investigated the killer cell immunoglobulin-like receptor (KIR) genes and HLA-C1/C2 dimorphism in 819 healthy, unrelated individuals composed of two southern Chinese Han populations (Hunan Han and Guangdong Han) and two northern Chinese populations (Inner Mongolia Han and Inner Mongolia Mongol), using polymerase chain reaction-sequence-specific priming (PCR-SSP) method. Fifty-one Chinese families were used to determine KIR haplotypic configuration. Our data showed that KIR2DL4, KIR3DL2, KIR3DL3, and KIR3DP1 genes were present in all of the 819 individuals. However, KIR2DL4 and KIR3DP1 genes were not detected in two members of a northern Chinese family. None of the KIR genes showed significant difference between the four populations. Thirty-five different KIR gene profiles were identified, one of which has not been previously reported in the Allele Frequencies KIR database. Eleven distinct KIR haplotypic configurations were determined through family analysis. Individuals with KIR2DLl and KIR2DL3 genes but lacking KIR2DSl and KIR2DS2 genes, coupled with HLA-C1 (Asn(80)) homozygosity, predominated in each population. At least one known inhibitory KIR-HLA pair was detected in each individual. The findings shown here are valuable for future studies of the potential role of KIR genes as well as KIR-HLA interaction in disease susceptibility in related ethnic groups.  相似文献   
999.
A computer simulation model based on an analytic flow velocity distribution is proposed to generate Doppler ultrasound signals from pulsatile blood flow in the vessels with various stenosis degrees. The model takes into account the velocity field from pulsatile blood flow in the stenosed vessels, sample volume shape and acoustic factors that affect the Doppler signals. By analytically solving the Navier-Stokes equations, the velocity distributions of pulsatile blood flow in the vessels with various stenosis degrees are firstly calculated according to the velocity at the axis of the circular tube. Secondly, power spectral density (PSD) of the Doppler signals is estimated by summing the contribution of all scatterers passing through the sample volume grouped into elemental volumes. Finally, Doppler signals are generated using cosine-superposed components that are modulated by the PSD functions that vary over the cardiac cycle. The results show that the model generates Doppler blood flow signals with characteristics similar to those found in practice. It could be concluded that the proposed approach offers the advantages of computational simplicity and practicality for simulating Doppler ultrasound signals from pulsatile blood flow in stenosed vessels.  相似文献   
1000.
Zhao A  Xiang Y  Xu J  Li Q  Wang L  Xing Q  Zhang Z  Liu Y  Feng G  He L  Zhao X 《Neuroscience letters》2012,522(2):85-91
The missing heritability of polygenic schizophrenia after genome-wide association studies (GWAS) can be potentially accounted for by the fact that most dynamic multiallelic copy number variants (CNVs) overlap segmental duplications (SDs). The FCGR locus covers this category of complex CNVs and it has long been postulated to harbor variants conferring the risk of schizophrenia. However, such association remains unproven. We used a case-control design to investigate CNV-based association with the disease. Data were obtained from 598 unrelated schizophrenia patients and 959 normal controls of Han ancestry from Shanghai. A total of four copy number (CN) probes in the FCGR locus were detected using TaqMan® Copy Number Assay. SPSS version 16.0 was used for the statistical analyses. And the frequency distributions of target CN in FCGR locus were very similar between controls and cases, whereas the CNV frequency differed markedly among different target CN analyzed in the two cohorts. When compared with the predominant two copies per diploid genome, a distinct non-protein-coding CN deletion region containing regulatory sequences was detected by probe Hs04194069_cn. Taken together, we found no evidence of association of target CNVs in the FCGR locus with schizophrenia. However, our negative findings suggest that more detailed next generation sequencing-based association studies are needed to fully evaluate the contribution of this category of complex CNVs to the disease.  相似文献   
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