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71.
目的 :构建重组真核表达质粒pcDNA3.1/IL 18,并在哺乳动物细胞COS 7和Rlc310中进行瞬时和稳定性表达。方法 :从含hIL 18基因的中介载体 pGEM TEasy( pGEM T/hIL 18)中 ,以限制性内切酶酶切方法获得目的片段 ,克隆入真核表达质粒 pcDNA3.1( )中。以脂质体法转染COS 7和Rlc310细胞 ,用RT PCR检测IL 18mRNA的水平 ,免疫组化染色法检测蛋白表达。结果 :构建了hIL 18基因的重组真核表达质粒pcDNA3.1/IL 18,并可在哺乳动物细胞中瞬时、稳定表达 ,获得了可稳定表达hIL 18基因的Rlc310细胞株。结论 :pcDNA3.1/IL 18的构建及表达 ,为IL 18抗肿瘤作用的研究奠定了基础  相似文献   
72.
We compared the effects of in vivo administration of the anti-T-cell receptor (TCR) alpha beta monoclonal antibody (mAb) (H57-597) to those of the anti-CD3 mAb (145-2C11), with or without anti-NK1.1 mAb (PK136), on xenogeneic skin graft survival in mice. In anti-TCR alpha beta mAb-treated B6 mice, F344 rat skin grafts survived for about 54 days, whereas in anti-CD3 mAb-treated B6 mice with or without anti-NK1.1 mAb treatment grafts survived about 25 days. In anti-TCR alpha beta mAb-treated B6 mice, TCR alpha beta-bearing T-lymphocyte function was completely abrogated, although TCR gamma delta-bearing T-lymphocyte function was still intact on day 9. In the anti-CD3 mAb-treated mice, the functions of both types of T lymphocytes were completely abrogated. On day 32, when most of the skin xenografts had been rejected in the anti-CD3 mAb-treated mice, the functions of both T lymphocytes had recovered considerably, and could actually respond to F344 antigens. In contrast, the function of TCR alpha beta-bearing cells had only partially recovered in the anti-TCR alpha beta mAb-treated mice. Finally, natural killer (NK) activity in the anti-TCR alpha beta mAb-treated mice was intact on day 32, when rat skin grafts still survived. In contrast, NK activity in the anti-CD3 mAb plus anti-NK1.1 mAb-treated mice did not recover on day 32, when skin xenografts had already been rejected. These results suggest that TCR gamma delta-bearing T cells and NK cells by themselves, at least in the absence of TCR alpha beta-bearing T cells, do not mediate xenogeneic skin graft rejection in mouse/rat combinations.  相似文献   
73.
促肝细胞生长素诱导人肝癌细胞(BEL-7402)凋亡   总被引:1,自引:0,他引:1  
本文从细胞学、DNA凝胶电泳、流式细胞术三方面研究促肝细胞生长素(pHGF)在体外对肝癌细胞增殖活性的影响。结果表明:pHGF对肝癌BEL-7402细胞增殖有抑制作用,并存在剂量和时间相关性。其48h的半数抑制浓度(ID50)为0.37mg/ml±0.04mg/ml。而37℃灭活的pHGF对BEL-7402细胞增殖在15h无抑制作用,在24和48h抑制作用很弱(ID50>1.5mg/ml)。DNA凝胶电泳结果表明,pHGF可诱导BEL7402细胞产生细胞凋亡(Apoptosis)。流式细胞术(FCM)结果显示:pHGF抑制BEL-7402细胞增殖过程是先使细胞停留在G0/G1期,继而诱导细胞产生凋亡。后两项结果均显示pHGF对人肝癌细胞凋亡的诱导里时间和剂量相关性。  相似文献   
74.
AIMS: Nodal expression of the carcinoembryonic antigen (CEA), cytokeratin 20 (CK20), and guanylyl cyclase C (GCC) genes was measured in tandem in patients with colorectal cancer (CRC) to assess whether there would be sufficient agreement between these markers in their ability to detect micrometastasis to qualify one of them as a universal marker, and whether frozen and paraffin wax embedded tissues would yield similar results. METHODS: One hundred and seventy five frozen lymph nodes (FT) and 158 formalin fixed, paraffin wax embedded lymph nodes (PET) from 28 CRC cases were analysed using gene specific quantitative real time polymerase chain reaction, carried out on the LightCycler system with SYBR Green chemistry. RESULTS: There was significant disparity in positive detection of the three biomarkers in FT versus PET, with notable agreement achieved only for CEA (66.6%) in FT versus PET in Dukes' B disease, and between CK20 and GCC (44.6%) in FT, also in Dukes' B disease. One patient with full concordance in all three tumour markers with both tissue types suffered a relapse and died within two years of follow up. CONCLUSIONS: There was considerable discordance in the positive detection of the three tumour markers in both tissue types (FT versus PET). This brings into question whether using a single tumour marker to detect micrometastasis in one tissue type (FT or PET) is adequately representative, and challenges the concept of universal markers for molecular CRC metastatic detection. Multiple tumour markers would predict more accurately the metastatic potential of Dukes' B CRCs.  相似文献   
75.
目的探求青少年归因方式与人际信任的关系。方法运用一般情况调查表、I—E量表、信任量表对413名青少年进行测查。结果①青少年的归因方式在性别、是否留守上均存在显著差异;②青少年的人际信任在性别、是否留守上均不存在显著差异;③青少年的归因方式对人际信任有极其显著的影响。结论青少年的归因方式极其显著地影响其人际信任。  相似文献   
76.
儿童退缩和同伴关系的相关   总被引:6,自引:2,他引:6  
目的:用元分析方法对近20年关于儿童退缩和同伴关系相关的研究结果进行总结。方法:用多水平分析技术对儿童退缩和同伴接受的相关、退缩和同伴拒绝相关的研究结果进行总结分析。结果:儿童退缩和同伴接受之间有显著的负相关关系,退缩和同伴拒绝之间有低度的非负相关关系,各研究结果之间的变异显著。结论:退缩导致儿童不良的同伴关系。  相似文献   
77.
Serotype distribution and antibiotic resistance (AR) among group B streptococci (GBS) affect GBS disease prevention strategies, but vary among patient groups. A multiplex PCR-based reverse line blot (mPCR/RLB) hybridisation assay was used to compare the distributions of GBS serotypes, serotype III subtypes and AR-associated genes among 666 invasive isolates from 663 patients, divided into five age groups: infants, early-onset (EO; 0-6 days) and late-onset (LO; 7-90 days); children (aged 3 months to 14 years); women of childbearing age (WCBA; aged 15-45 years); and other adults (males aged >15 years; females aged >45 years). Serotypes Ia and V and serosubtype III-1 accounted for 60% of infections. Serosubtype III-2, which corresponds to a virulent clone belonging to sequence type (ST)17, was relatively uncommon overall (7%), but was associated strongly with LO infant infections, in which it was significantly more common than in adult infections (25/104 (24%) vs. 9/392 (2%), p <0.0001) or in EO infections (25/104 (24%) vs. 14/155 (9%), p <0.005). Erythromycin resistance genes were found in 8% of all isolates (ermB 3%, ermA 2.5% and mefA/E 2%), in 11-15% of isolates of serotypes II and V and subtype III-1, but in none of the isolates of serosubtype III-2 (III-2, 0/49 vs. all others, 54/618 (9%), p <0.04). In summary, the virulent serosubtype III-2 was associated strongly with LO infant GBS infection, but was less likely than other serotypes or serosubtype III-1 to carry AR genes.  相似文献   
78.
沈燕  仲人前 《现代免疫学》1998,18(4):210-211
本文采用生物素-亲合素-碱性磷酸酶法(ABC-AKP)检测10例正常人血清和7例系统性红斑狼疮(SLE)病人血清中IgG类抗-Sm/抗-U_1RNP抗体对Hep-2细胞的进入作用.结果表明:自身抗体能够进入存活的Hep-2细胞,患者组阳性者4例(57.14%),对照组皆为阴性(P<0.05).讨论了自身抗体进入活的靶细胞在自身免疫性疾病发病中的意义.  相似文献   
79.
目的:为带臂外侧上皮神经及其营养血管筋膜皮瓣提供解剖学基础.方法:32例经灌注红色乳胶的成人上肢标本,对臂外侧上皮神经及其营养血管等进行了较详细的应用解剖学研究.结果:臂外侧上皮神经在均由腑神经发出,起点横径为1.5±0.4mm,在三角肌深方斜向外下3.6±1.1cm从该肌后缘中1/3浅出肌间隔,分为上支和下支,分布于三角肌后部、外侧部和臂外侧上部.该神经的营养血管起源于旋肱后动脉,起点外径为0.9±0.4mm;其行程、分支和分布均同在神经,供血范因为14.8×9.8cm~2,并与周围的皮动脉存在丰富吻合.结论:带臂外侧上皮神经及其营养血管筋膜皮 瓣可视受区需要设计成游离瓣或旋转瓣,用于修复邻近部位、手或颌面部缺损.  相似文献   
80.
The TGF-1(–/–) mouse is a murine model for systemic autoimmune disease. The aim of this study is to elucidate the immunological mechanism that leads to multifocal tissue inflammation and autoantibody production in TGF-1(–/–) mice. Heart, lung, liver, and salivary gland from TGF-1(–/–) were assessed for CD154 expression by RT-PCR and immunohistochemistry. Compared to wild-type littermates, CD154 expression was elevated in all tissues studied. Furthermore, IL-12 mRNA was expressed in the salivary gland and heart of TGF-1(–/–) mice and not in wild-type littermates. This suggests that the CD154 pathway is activated in these tissues. This shows that TGF-1 regulates CD154 expression leading to spontaneous IL-12 production and autoimmunity.  相似文献   
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