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991.
992.
Background: The FAS and FASL system plays a key role in regulating apoptotic cell death and corruption of this signalling pathway has been shown to participate in immune escape and tumorigenesis. There is reduced expression of FAS but elevated expression of FASL in many types of human cancers including lung cancer. We recently reported an association between functional polymorphisms in FAS (–1377G→A) and FASL (–844T→C) and risk of oesophageal cancer.  相似文献   
993.
中国广东汉族群体HLAⅡ类基因多态性的研究   总被引:3,自引:1,他引:3  
为探讨中国广东汉族群体HLAⅡ类基因多态性,采用PCR/SSO方法,随机选择102名广东籍汉族人进行了HLAⅡ类基因的DNA分型。测定了包括HLA-DRB1,DRB3,DRB5,DQA1,DQB1和DPB1等6个基因座位的等位基因。结果:共检出23种DRB1,3种DRB3,4种DRB5,8种DQA1,12种DQB1和12种DPB1基因。该人群的HLAⅡ类等位基因多态性的典型性表现在HLA-DRB*1202的不寻常优势和DRB1*02单倍型的结构的高度复杂性。还发现了很高频率的一个近年才被正式命名的DP新型:HLA-DPB1*2101,并且此型具有极不寻常的DRB1*1202-DPB1*2101的连锁不平衡。为分子流行病学研究提供了资料。  相似文献   
994.
<正> Spinal cord injury(SCI)is such a serious disease that itwould bring heavy burdens of both health and economy tothe victims as well as the society.Although worldwide med-ical researchers of neuroscience have made great efforts toattempt to solve this big problem for nearly a century, there  相似文献   
995.
We studied the development of respiratory syncytial virus (RSV)-specific IgE and the release of histamine in nasopharyngeal secretions from 79 infants with various forms of respiratory illness due to RSV. RSV-IgE was measured by an enzyme-linked immunosorbent assay; specificity was confirmed by appropriate blocking experiments. Histamine content in the secretions was determined by fluorimetric methods. RSV-IgE was detectable in only one of 19 patients with RSV infection without wheezing, but was detectable in the majority of 60 patients with wheezing (P less than 0.01). Titers of RSV-IgE were significantly higher in patients with wheezing (P less than 0.05). Histamine was detectable in secretions of some patients with all forms of illness but was detected significantly more often (P = 0.05) and in higher concentrations in patients with wheezing. Peak titers of RSV-IgE and concentrations of histamine correlated significantly with the degree of hypoxia (P less than 0.001). Formation of RSV-specific IgE and release of histamine may adversely affect the outcome of RSV infection.  相似文献   
996.
A pulsatile left ventricular assist device (LVAD) was used to support the aortic blood pumping function of an injured left ventricle, and as a result helped its recovery. It is important to observe a left ventricle's pumping status and to adjust the operating status of a LVAD to reduce the left ventricle's pumping load and thus to enhance its recovery. To observe the left ventricle's pumping status, an electrocardiogram (ECG) signal is generally used because it is a result of the natural heart's blood pumping function. In this paper, we describe the development of an ECG based counterpulsation control algorithm that prevents simultaneous aortic blood co-pumping by a left ventricle and a moving-actuator type pulsatile LVAD and as a result, reduces the natural heart's pumping load. In addition, to verify the algorithm's applicability for LVAD control we designed three ECG based automatic pump control algorithms that use a developed counterpulsation control algorithm. These algorithms control the operating status of a LVAD automatically and, at the same time, maintain a counterpulsing status. The results of in vitro experiments show that the counterpulsing effect between a left ventricle and a LVAD was successfully produced and that the newly designed automatic pump control algorithms met their own control purposes with a counterpulsing effect.  相似文献   
997.
探讨一种由结肠癌细胞表达的细胞外基质Reelin在淋巴结转移中的作用.构建了99例结肠癌及其癌旁组织的组织芯片进行免疫组织化学染色,探测其表达强度并结合临床资料进行分析.结果显示,Duke's A,B,C,D分期与结肠癌细胞Reelin表达强度无关,结肠癌细胞Reelin表达强度与其淋巴结转移潜能相关,结肠癌细胞Reelin表达强度每增加一个单位,其转移进入淋巴结的能力将增加3.523倍.结肠癌细胞表达Reelin与其淋巴结转移密切相关,Reelin可以作为结肠癌淋巴结转移预测的一个新指标.  相似文献   
998.
OBJECTIVE: To investigate the relationship between the plasminogen activator inhibitor (PAI-1) polymorphisms and endometrial hypoplasia in infertile women. METHODS: The study was conducted in 105 primary infertile patients with endometrial hypoplasia diagnosed by pathology and the thickness of endometrium by B-mode ultrasound and 85 controls who were not pregnant and had normal fertility. The -675 4G/5G polymorphism in the PAI-1 gene was detected by polymerase chain reaction-restriction fragment length polymerphim analysis. RESULTS: The frequencies of 4G/4G genotype and 4G allele of the PAI-1 gene were higher in the patient group (48.6% and 66.2%) than in the normal controls (22.4% and 47.1%) (P < 0.01). ThePAI-1 4G/4G genotype was significantly associated with endometrial hypoplasia in the infertile patients (OR=4.9, 95% CI: 2.10-10.12). CONCLUSION: The present findings suggest that the 4G/5G polymorphism of the PAI-1 gene was associated with endometrial hypoplasia in infertile patients.  相似文献   
999.
肺癌患者血清TSGF、CEA、CYFRA21—1和NSE水平的临床价值   总被引:1,自引:2,他引:1  
目的:探讨血清TSGF、CEA、CYFRA21-1和NSE水平的临床价值。方法:采用放射免疫分析测定了179例肺癌、48例肺良性病变和51例正常对照组的血清TSGF、CEA、CYFRA21-1和NSE的水平。结果:在NSCLC中,37例I~II期鳞癌血清中TSGF、CEA和NSE水平与肺良性病变无明显差异(P均>0.05),32例I~II期腺癌血清中NSE也与肺良性病变无明显差异(P>0.05);其余,NSCLC和SCLC血清中TSGF、CEA、CY-FRA21-1和NSE水平明显增高,均与肺良性病变具有明显差异(P<0.05~0.01),从总体而言,随着病变的严重程度增加,肺癌标志物水平也增高。51例正常对照组血清TSGF、CEA、CYFRA21-1和NSE水平分别为(64.1±14.8)U/ml,(3.51±1.1)ng/ml,(2.6±1.4)ng/ml和(5.1±3.6)ng/ml。结论:肺癌的诊断中,以血清CY-FRA21-1测定为最佳,其次为TSGF和CEA,最差NSE,故肺癌标志物的联检是诊断肺癌的最佳选择。  相似文献   
1000.
目的:构建抗角蛋白抗体基因的真核表达载体,并在CHO(dhfr^-)细胞中表达。方法:从含抗角蛋白抗体基因的原核Fab表达载体中,扩增VH及VL基因。以回收的PCR产物为模板,用重叠PCR扩增带有前导序列的VH、VL基因。经XbaⅠ/BamHⅠ和XhoⅠ/HindⅢ酶切后,分别插入真核表达载体pWD中,构建重组载体pWDkH。经PCR和测序鉴定正确后,用lipofectAMINE2000转染CHO(dhfr^-)细胞。取培养上清检测抗人角蛋白全IgG的表达。结果:构建了抗人角蛋白基因的真核表达载体pWDkH,并在CHO(dhfr^-)细胞中表达:结论:在CHO(dhfr^-)细胞中成功地表达了具有抗原结合活性的抗人角蛋白IgG,为其临床应用奠定了基础。  相似文献   
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