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981.
膜型/分泌型MICA对NK细胞受体NKG2D的相反调节效应及其对NK细胞受体谱的影响 总被引:21,自引:0,他引:21
目的 观察膜型和分泌型MICA对NK细胞受体表达的影响 ,以探讨NK细胞抗肿瘤活化机制及肿瘤细胞表达MICA分子的意义。方法 用MTT法测定人NK细胞系 (NK92 )的细胞毒活性 ;用RT PCR或FACS检测NK细胞受体 (NKG2D ,NKG2A B ,KIR2DL1,KIR2DS1)及NKG2D的识别配体MICA的表达。结果 肿瘤细胞表面的MICA分子可上调NKG2D的表达 ,下调抑制性受体NKG2A B和KIR2DL1的表达 ;而分泌型MICA (sMICA)分子对NKG2D及抑制性受体的表达均有抑制作用。结论 膜型MICA分子可上调NKG2D的表达 ,激发NK细胞对肿瘤细胞的细胞毒效应 ;分泌型MICA分子则通过降低NKG2D的表达下调机体的抗肿瘤免疫效应 ,肿瘤细胞分泌sMICA分子为肿瘤发生免疫逃逸的机制之一。 相似文献
982.
GABRD encoding a protein for extra- or peri-synaptic GABAA receptors is a susceptibility locus for generalized epilepsies 总被引:11,自引:0,他引:11
Dibbens LM Feng HJ Richards MC Harkin LA Hodgson BL Scott D Jenkins M Petrou S Sutherland GR Scheffer IE Berkovic SF Macdonald RL Mulley JC 《Human molecular genetics》2004,13(13):1315-1319
A major challenge in understanding complex idiopathic generalized epilepsies has been the characterization of their underlying molecular genetic basis. Here, we report that genetic variation within the GABRD gene, which encodes the GABAA receptor delta subunit, affects GABA current amplitude consistent with a model of polygenic susceptibility to epilepsy in humans. We have found a GABRD Glu177Ala variant which is heterozygously associated with generalized epilepsy with febrile seizures plus. We also report an Arg220His allele in GABRD which is present in the general population. Compared with wild-type receptors, alpha1beta2Sdelta GABAA receptors containing delta Glu177Ala or Arg220His have decreased GABAA receptor current amplitudes. As GABAA receptors mediate neuronal inhibition, the reduced receptor current associated with both variants is likely to be associated with increased neuronal excitability. Since delta subunit-containing receptors localize to extra- or peri-synaptic membranes and are thought to be involved in tonic inhibition, our results suggest that alteration of this process may contribute to the common generalized epilepsies. 相似文献
983.
骨髓间充质干细胞复合羟基磷灰石/磷酸三钙植骨材料的体外研究 总被引:1,自引:1,他引:1
目的研究兔骨髓间充质干细胞(BMSCs)在羟基磷灰石/磷酸三钙(HA/TCP)植骨材料上的黏附增殖情况。方法抽取兔股骨骨髓,进行贴壁培养BMSCs。在成骨诱导液中诱导BMSCs,于7d用钙钴法检测碱性磷酸酶活性,10d进行茜素红矿化结节染色;在成脂诱导液中诱导BMSCs,于21d进行油红O染色。将BMSCs接种到HA/TCP植骨材料上,加入成骨诱导液,采用倒置显微镜、荧光显微镜及扫描电镜检测,并采用四氮唑蓝(MTT)比色法测定HA/TCP植骨材料上BMSCs的增殖情况。结果BMSCs在成骨诱导液中7d碱性磷酸酶呈强阳性,10d矿化结节染色呈橘红色;在成脂诱导液中,21d油红O染色呈阳性。BMSCs在HA/TCP植骨材料上孔隙周围及孔隙内生长良好并大量增殖。MTT分析结果显示,HA/TCP对BMSCs的体外增殖无抑制作用。结论BMSCs与HA/TCP植骨材料有良好的生物相容性。 相似文献
984.
报道用骨间前血管腕背支骨膜瓣移位修复骨不连、骨坏死的手术方法及疗效。方法:根据应用解剖学研究,设计以骨间前动脉腕背支为蒂的骨膜瓣,顺行移位修复尺、桡骨骨不连,逆行移位修复手舟骨、月骨不连与骨坏死。结果:临床应用19例,随访1年,在术后3~6月均达到骨愈合和骨坏死修复,关节活动功能明显改善。结论:骨间前血管腕背支为蒂的骨膜瓣移位术适合邻近骨不连、骨坏死修复。 相似文献
985.
BRI基因在一对转移能力不同的肺腺癌细胞系中的序列分析与表达研究 总被引:1,自引:0,他引:1
目的 确认淀粉样纤维蛋白基因(amyloid fibrils,BRI)基因在l对同源但转移能力不同的肺腺癌细胞系AGZY83-a和Anip973中的序列并分析其表达。方法 采用测序技术,Northern印迹杂交。G显带后荧光原位杂交分析BRI基因在肺腺癌细胞系的序列与表达。结果 BRI基因在高转移肺腺癌细胞系Anip973中高表达,在其低转移母系AGZY83-a中低表达,两细胞系BRI基因染色体定位区均存在断裂重排。该基因染色体定位区在Anip973中出现扩增。已知BRI基因的-116bp~-5bp处碱基序列和-115bp~-5bp处碱基序列在AGZY83-a和Anip973中分别突变为CTCAGCAGCCCGC和TCAGCCGC。结论 BRI基因在转移能力不同的肺腺癌细胞系差异表达与该基因的染色体定位区域的断裂重排无关,与该基因染色体定位区拷贝数增加及5′非翻译区存在不同的突变可能相关。 相似文献
986.
Recurrent genetic alterations in 26 colorectal carcinomas and 21 adenomas from Chinese patients 总被引:5,自引:0,他引:5
He QJ Zeng WF Sham JS Xie D Yang XW Lin HL Zhan WH Lin F Zeng SD Nie D Ma LF Li CJ Lu S Guan XY 《Cancer Genetics and Cytogenetics》2003,144(2):112-118
Colorectal cancer (CRC) is one of the most common malignancies worldwide. The incidence of CRC in the Chinese population has increased dramatically during the last two decades; however, nonrandom chromosomal alterations in Chinese patients have not been described. In the present study, comparative genomic hybridization (CGH) was applied to detect recurrent chromosome alterations in 26 primary colorectal carcinomas and 21 colorectal adenomas from Chinese patients. In CRC, several recurrent chromosomal changes were found, including gains of 8q (14/26 cases, 54%), 20q (54%), 3q (50%), 13q (50%), 5p (46%), 7p (42%), 7q (42%), and 12p (38%) and losses of 18q (65%) and 17p (42%). From comparison with previous CGH studies, the frequent gains of 3q and 12p might be distinctive occurrences in Chinese patients. The distribution of frequently found chromosomal alterations in different locations was studied. The gain of 20q was more frequently found in colon cancer (P<0.01) and the gain of 12p was more frequently found in rectal cancer. Chromosomal alterations were found in 19/21 of adenomas; the most frequent chromosomal alteration was the loss of 18q (9/21 cases, 43%). These recurrent alterations provide several starting points for the isolation of candidate oncogenes and tumor suppressor genes. 相似文献
987.
背景:目前临床上多数认为,肩部疾病如肩锁关节脱位、肩峰下撞击综合征等与肩锁关节的解剖形态有很大的关系,但国内外文献很少有关于肩锁关节的形态学数据支持,特别对于肩锁关节关节盘的解剖学研究。同时肩锁关节属于微动关节,参与肩关节的联合运动,现临床上有关肩锁关节脱位的手术方式繁多,较流行的手术方式多为刚性固定,并未保留其微动特点以及锁骨和肩胛骨的运动特点,其中关节盘的取舍目前国内外并无大样本多中心对照研究。目的:对肩锁关节及关节盘行相关解剖学研究,用于更好地指导肩部疾病的诊治。方法:对58具肩锁关节尸体标本(同济大学解剖教研室提供)进行形态学及组织结构研究,共获得58个肩峰、58个锁骨和36个关节盘(包括完全型和不完全型)。采用BIGLIANI肩峰形态分型、DEPALMA锁骨形态分型、EMURA肩锁关节盘分型,获得各肩峰与锁骨组合下关节盘出现的频率并行苏木精-伊红染色(上海市普陀区人民医院提供)。结果与结论:①在58个肩锁关节尸体中,肩锁关节盘type1型共15例,所占比例最高,为25.9%;type3a型共4例,所占比例最少,为6.9%。②Ⅰ型肩峰32个,所占比例最高,为55.2%;Ⅲ型肩峰3个,所占比例最低,为5.2%。③Ⅰ型锁骨27个,所占比例最高,为46.6%;Ⅲ型锁骨9个,所占比例最低,为15.5%。④以Ⅰ型及Ⅱ型肩峰与Ⅰ型锁骨组合所占比例较大,分别为24.1%和22.4%,以Ⅲ型肩峰对Ⅰ型锁骨所占比例最小,为0%。⑤而在Ⅰ型肩峰与Ⅰ型锁骨组合下type1型和type2b型关节盘所占比例最大,分别为35.7%和28.6%;Ⅱ型肩峰与Ⅰ型锁骨组合下type2a型和type1型关节盘所占比例最大,分别为38.5%和23.1%。⑥苏木精-伊红染色在组织切片中可以发现,关节盘中的细胞外基质清晰可辨,细胞形态饱满,含有丰富的细胞质,提示为软骨细胞,即形成纤维软骨的主要成分。此外,从关节囊顶端和底端两侧可见部分骨膜纤维层移行至关节盘内侧,考虑共同组成关节盘结构,即关节盘由近骨面的软骨细胞及远离骨面的纤维层共同构成。 相似文献
988.
Mice with the scid mutation have a defect in the V(D)J recombinase. In order to
determine whether the SCID product is normally present in mature B cells that do not
have the recombinase activity, scid pre-B cells were fused with myeloma cells. It was
found that in the hybrid cells, a rearrangement test gene was correctly joined
immediately after fusion. The same test gene was aberrantly rearranged in the scid pre-B
cells. Stable hybrids between the scid pre-B and the myeloma cells had lost the
expression of RAG-1 and RAG-2 genes, supporting the previous finding of an inhibitor
of rearrangement in myeloma cells that acts shortly after fusion. Thus, mature B cells
apparently contain the SCID product, the wild type SCID function is not competitively
interfered with by products present in scid pre-B cells, and the SCID product seems not
to be a target for the recombinase inhibitor. 相似文献
989.
Yen Yi Chou Te Yu Lin Jung Chung Lin Ning Chi Wang Ming Yieh Peng Feng Yee Chang 《Journal of microbiology, immunology, and infection》2008,41(2):124-129
BACKGROUND AND PURPOSE: Vancomycin-resistant enterococci (VRE) have emerged as important nosocomial pathogens. This study was conducted to clarify the clinical features and outcome of patients with vancomycin-resistant enterococcal bacteremia. METHODS: Patients with vancomycin-resistant enterococcal bacteremia treated at a medical center in northern Taiwan between November 1998 and July 2006 were reviewed. Clinical and bacteriological characteristics of Enterococcus faecium and Enterococcus faecalis were compared. RESULTS: Twelve patients (6 males and 6 females) were included for analyses. The mean age was 69.3 years (range, 40 to 86 years), and 8 cases (66.7%) were older than 65 years. All patients had underlying disease. Two patients received total hip replacement before development of VRE bacteremia. Twelve patients had prior exposure to broad-spectrum antimicrobial therapy. Ten patients had prior intensive care unit stay and prior mechanical ventilation before VRE bacteremia. All of the patients (n = 12) had an intravascular catheter in place. Bacteremia was caused by E. faecalis in 4 patients and by E. faecium in eight. The portals of entry included urinary tract (8.3%), skin, soft tissue and bone (41.7%) and unknown sources (50.0%). E. faecium showed a higher rate of resistance to ampicillin and teicoplanin than E. faecalis (87.5% vs 0.0%, p=0.01). The 60-day mortality rate was higher in patients with E. faecium bacteremia than E. faecalis bacteremia (62.5% vs 0.0%), although statistical significance was not obtained (p=0.08). CONCLUSIONS: VRE bacteremia may have an impact on the mortality and morbidity of hospitalized patients. Patients with bacteremia caused by vancomycin-resistant E. faecium had a grave prognosis, especially immunosuppressed patients. The prudent use of antibiotics and strict enforcement of infection control may prevent further emergence and spread of VRE. 相似文献
990.
阐述了遗传算法优化多点超声聚焦的方法以及球面相控阵声场计算方法。对实验室研发的256阵元相控阵聚焦超声治疗系统作了简介。利用此遗传算法和声场计算方法,对轴上和离轴单焦点以及轴对称六焦点和非轴对称四焦点进行了256阵元相控阵的声场仿真,并观察了实验室研发的256阵元相控阵聚焦超声治疗系统作用于有机玻璃和透明仿体的实验结果。用遗传算法和声场计算方法的仿真和系统实验结果表明,此方法可在实际聚焦手术中准确地控制3维单焦点和3维多焦点。 相似文献