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101.
Fasth AE Cao D van Vollenhoven R Trollmo C Malmström V 《Scandinavian journal of immunology》2004,60(1-2):199-208
CD4+ T cells lacking the costimulatory molecule CD28 have been described both in elderly individuals and in chronic inflammatory disorders, one being rheumatoid arthritis (RA). We, in this study, provide a comprehensive characterization of cell surface markers on and function of such CD28nullCD4+ T cells, as well as correlations with clinical parameters. We conclude that of all surface markers associated with these cells, only CD57 and CD11b are expressed on the majority of them. This CD28null population occurred in one-third of patients with RA and was independent of clinical characteristics. The population was persistent and expanded in peripheral blood, but was excluded from the joint in most patients. Functionally, CD28nullCD4+ T cells were potent effector memory cells with regard to their proliferation and cytokine-secretion profiles. This capacity correlated with a hitherto unpublished surface phenotype, the cells being uniformly CCR7- and CD43high. Moreover, a new terminally differentiated CD45RA+CCR7- population of CD4+ T cells was identified. We would like to suggest that in the unbalanced immune system of patients with autoimmune disease and chronic infection an expanded CD28nullCD4+ T-cell population able to secrete high levels of cytokines is likely to contribute to disease manifestations. 相似文献
102.
Pan J Zhang M Wang J Wang Q Xia D Sun W Zhang L Yu H Liu Y Cao X 《Immunology letters》2004,94(1-2):141-151
Maturation of dendritic cells (DC) is critical for efficient antigen presentation and initiation of an immune response. Interferon-gamma (IFN-gamma) is an important Th1 cytokine. In this study, we investigated the role of IFN-gamma in DC maturation using either IFN-gamma receptor deficient- or IFN-gamma overexpression-models. We showed that immature DC generated in vitro from bone marrow (BM) progenitor cells produced low level of IFN-gamma. After LPS stimulation, DC produced more IFN-gamma, and IFN-gamma productions were at comparable levels among C57BL/6 mice-derived DC (C57BL/6 DC), wild-type 129 mice-derived DC (129 DC) and IFN-gamma receptor deficient 129 mice-derived DC (IFN-gammaR-/-DC). We found that IFN-gammaR-/-DC exhibited decreased expression of CD54, CD86, reduced capacity to secrete IL-1beta and IL-12p70, and impaired capacity to stimulate alloreactive T cells and to drive Th1 differentiation. Transfection of IFN-gamma gene into DC promoted DC to express higher CD40, CD54, CD80, CD86, CCR7 and I-Ab, secrete more IL-1beta and IL-12p70, and more potently activate both CD4 and CD8 T cells. These data suggest that IFN-gamma signaling pathway is important for the maturation of DC in an autocrine fashion. 相似文献
103.
Sbracia M Baldi M Cao D Sandrelli A Chiandetti A Poverini R Aragona C 《Human reproduction (Oxford, England)》2002,17(2):320-324
BACKGROUND: In babies born after ICSI procedures, an increase of de-novo sex chromosome abnormalities has been observed. Several hypotheses have been proposed to explain these findings: an increased rate of sex chromosome aneuploidy in sperm of oligozoospermic men, or a preferential location of the sex chromosomes in the sub-acrosomal region of the sperm nucleus which leads to a reduced DNA decondensation of this region. In order to investigate which theory may be more reliable, we studied the localization of sex chromosomes and their aneuploidy rate in sperm in men undergoing ICSI. METHODS: Using fluorescent in-situ hybridization we studied sex chromosome localization and the aneuploidy rate for sex chromosomes and chromosome 18 in 20 oligospermic men undergoing ICSI and in 10 controls. RESULTS: In 40.94 and 52.92% of cases, the X and Y chromosomes respectively were localized in the sub-acrosomal region of the sperm nucleus compared with only 14.29% of cases of chromosome 18 (P < 0.001). An increase of sex chromosome aneuploidy in sperm of oligospermic men was observed; 2.91 versus 0.69% of controls (P < 0.001). CONCLUSIONS: Sex chromosomes are localized preferentially in the sub-acrosomal region of sperm and sex chromosome aneuploidy rate in the sperm of oligozoospermic men is higher than in controls. 相似文献
104.
根据自身免疫性甲状腺疾病发病机制的独特型-抗独特型免疫免疫学说,用兔抗人TSHAb检测TSH抗独特型抗体(TSHAb2)。以正常人为对照,以其结合率^-x+2s为正常值上限,大于此值为阳性。60例TRAb阳性病人,65%病人TSHAb2阳性,而40例TRAb阳性病人中,只有5%病人TSHAb2阳性。两组差异显著(P〈0.05)。TRAb和TSHAb2呈正相关(r=0.645,P〈0.01)。同时用 相似文献
105.
In this paper, we report a pregnancy at risk for beta thalassaemia in which the fetal red blood cell volume was reduced while that of the mother was relatively great, so that the presence of a fetal red blood cell population in a mixed maternal-fetal sample was difficult to recognise. The molecular basis for these haematological phenotypes was clarified by follow up examination and alpha globin gene mapping. These indicated that the fetus was heterozygous for beta thalassaemia and had deletion of three alpha globin structural genes, while the mother, heterozygous for beta thalassaemia, also had deletion of two alpha globin structural genes. When the coinheritance of alpha thalassaemia is suspected, it is necessary to examine carefully the red blood cell distribution of a placental sample, so that the presence of a population of fetal red blood cells is not missed. 相似文献
106.
The deltaccr5 mutation conferring protection against HIV-1 in Caucasian populations has a single and recent origin in Northeastern Europe 总被引:6,自引:0,他引:6
Libert F; Cochaux P; Beckman G; Samson M; Aksenova M; Cao A; Czeizel A; Claustres M; de la Rua C; Ferrari M; Ferrec C; Glover G; Grinde B; Guran S; Kucinskas V; Lavinha J; Mercier B; Ogur G; Peltonen L; Rosatelli C; Schwartz M; Spitsyn V; Timar L; Beckman L; Vassart G 《Human molecular genetics》1998,7(3):399-406
The chemokine receptor CCR5 is encoded by the CMKBR5 gene located on the
p21.3 region of human chromosome 3, and constitutes the major co- receptor
for the macrophage-tropic strains of HIV-1. A mutant allele of the CCR5
gene, Delta ccr5 , was shown to provide to homozygotes with a strong
resistance against infection by HIV. The frequency of the Delta ccr5 allele
was investigated in 18 European populations. A North to South gradient was
found, with the highest allele frequencies in Finnish and Mordvinian
populations (16%), and the lowest in Sardinia (4%). Highly polymorphic
microsatellites (IRI3.1, D3S4579 and IRI3.2, D3S4580 ) located respectively
11 kb upstream and 68 kb downstream of the CCR5 gene deletion were used to
determine the haplotype of the chromosomes carrying the Delta ccr5 variant.
A strong linkage disequilibrium was found between Delta ccr5 and specific
alleles of the IRI3.1 and IRI3.2 microsatellites: >95% of the Delta ccr5
chromosomes carried the IRI3.1-0 allele, while 88% carried the IRI3.2-0
allele. These alleles were found respectively in only 2 or 1.5% of the
chromosomes carrying a wild-type CCR5 gene. From these data, it was
inferred that most, if not all Delta ccr5 alleles originate from a single
mutation event, and that this mutation event probably took place a few
thousand years ago in Northeastern Europe. The high frequency of the Delta
ccr5 allele in Caucasian populations cannot be explained easily by random
genetic drift, suggesting that a selection advantage is or has been
associated with homo- or heterozygous carriers of the Delta ccr5 allele.
相似文献
107.
Sun Chang-ti孙昌惕 Cao Lu-cheng曹履诚and Han Ke-han韩可汉Institute of Urology Beijing Medical University Beijing 《中华医学杂志(英文版)》1987,100(12):935-939
The formation of calcium oxalate nephrolithiasis
can be estimated by measuring the concentration of
calcium oxalate versus the inhibitory role of crystal
formation in the urine. In recent studies, the
calcium oxalate saturation index and the inhibitory
activity (by modified Sarig's method) of the urine
during fasting and after oral calcium loading in
normal subjects and in patients with calcium nepliro-
lithiasis were determined. It was shown that, in
normal comrols after calcium loading the inhibitory
activity of the urine increased in parallel with the
increase in urinary excretion of calcium oxalate; in
contrast, in patients with kidney stones, it remained
unchanged or fell slightly. This abnormal response
might result in a disturbance of the saturation-inhibi-
tion balance and formation of kidney stone. In
normal individuals, there may be a "protective re-
sponse" to prevent the precipitation of calcium
oxalate when the urrine is oversaturated with calcium
oxalate while a defect of the "protective response"
in patients may be an important factor in calcium
oxalate stone formation. 相似文献
108.
目的观察高频重复经颅磁刺激(rTMS)联合认知行为治疗对脑卒中后焦虑(PSA)、脑卒中后抑郁(PSD)共病状态患者的影响。 方法采用随机数字表法将160例脑卒中后焦虑抑郁状态患者分为对照组和观察组。两组患者均给予脑卒中常规治疗、抗抑郁药物治疗和认知行为治疗,对照组同时给予高频rTMS假刺激治疗,观察组则给予高频rTMS真刺激治疗。观察4周后2组患者抑郁症状、焦虑症状、睡眠质量、日常生活能力改善情况。 结果两组患者汉密尔顿抑郁量表(HAMD)评分、汉密尔顿焦虑量表(HAMA)评分、匹兹堡睡眠指数量表(PSQI)、改良Barthel指数(MBI)在治疗前差异无统计学意义(P均>0.05)。治疗4周后,对照组和观察组的HAMD评分、HAMA评分、PSQI较治疗前下降,差异有统计学意义(P均<0.05),其中观察组下降更为明显,与对照组相比,差异有统计学意义(P<0.05)。对照组和观察组MBI与治疗前相比,均有明显提高,差异有统计学意义(P<0.05),而观察组和对照组相比,观察组分数提高更显著,差异有统计学意义(P<0.05)。观察组治疗有效率为87.50%,高于对照组的71.25%。两组之间差异有统计学意义(Uc=-3.45,P<0.001)。 结论高频rTMS治疗联合认知行为治疗和认知行为治疗均能有效改善PSA+PSD患者的焦虑抑郁症状、睡眠质量及日常生活能力,但高频rTMS治疗联合认知行为治疗的效果更加明显。 相似文献
109.
目的探讨基于胸痛中心急救流程在急性心肌梗死(AMI)患者救治中的应用效果。 方法选取镇江市急救中心2017年8月至2021年8月接诊的94例AMI患者为研究对象,其中男性50例,女性44例;年龄42~81岁,平均(60.37±4.31)岁。根据就诊顺序分为对照组和研究组,每组各47例,对照组患者接受常规急救流程,研究组患者接受基于胸痛中心基础上的急救流程,比较两组患者急救各环节时间、不良心血管事件发生率及患者满意度。 结果研究组患者急救各环节时间较对照组更短,两组比较差异有统计学意义(P<0.05);研究组患者不良心血管事件发生率显著低于对照组(6.38%比23.40%),两组比较差异有统计学意义(P<0.05);研究组患者满意度显著高于对照组(93.62%比78.72%),两组比较差异有统计学意义(P<0.05)。 结论基于胸痛中心急救流程可有效缩短急救过程中各环节时间,最大限度降低不良心血管事件发生风险,患者满意度高,对提高AMI患者救治效果、改善预后具有积极意义。 相似文献
110.
目的探讨妊娠期糖尿病(GDM)患者产后糖代谢异常(AGM)转归及其影响因素。方法选择2019年1月至12月,于四川大学华西第二医院孕期被诊断为GDM,并于产后4~12周进行75 g口服葡萄糖耐量试验(OGTT)筛查的1175例单胎妊娠产妇为研究对象。根据其产后糖代谢是否正常,将其分为研究组(n=361,产后AGM者)与对照组(n=814,产后糖代谢正常者)。采用回顾性分析方法,收集受试者一般临床资料及孕期与产后4~12周75 g OGTT结果等,并采用成组t检验或χ^(2)检验进行统计学分析。对GDM患者产后AGM转归相关影响因素进行单因素分析与多因素非条件logistic回归分析,探讨其AGM转归的独立影响因素。本研究遵循的程序符合病例收集医院伦理委员会制定的伦理学标准,得到该伦理委员会批准[审批文号:医学科研2021伦审批第(181)号]。结果①24~28孕周时,1175例GDM患者75 g OGTT结果提示,空腹血糖(FPG)及OGTT 1、2 h血糖指标中,1、2、3项升高者分别为639例(54.4%)、373例(31.7%)与163例(13.9%)。②产后4~12周时,1175例GDM患者75 g OGTT结果提示,产后糖代谢正常者为814例(69.3%),AGM为361例(30.7%),包括空腹血糖受损(IFG)为19例(1.6%),糖耐量受损(IGT)为294例(25.0%),IFG+IGT为23例(2.0%),疑似2型糖尿病(T2DM)患者为25例(2.1%)。③产后AGM转归影响因素的单因素分析结果显示,研究组GDM患者年龄、糖尿病家族史发生率,24~28孕周OGTT 1、2 h血糖值,以及2项血糖指标(OGTT 1、2 h血糖)均升高与3项血糖指标(FPG及OGTT1、2 h血糖)均升高者所占比例,均显著高于对照组,而研究组仅1项血糖指标(FPG或OGTT 1 h血糖)升高者所占比例,则显著低于对照组,2组比较,差异均有统计学意义(P<0.05)。④多因素非条件logistic回归分析结果:模型1将受试者年龄、糖尿病家族史及24~28孕周OGTT 1、2 h血糖值进行多因素logistic回归分析结果显示,糖尿病家族史及24~28孕周OGTT 1、2 h血糖值,均为GDM患者产后AGM转归的独立危险因素(OR=1.693、1.205、1.355,95%CI:1.208~2.373、1.088~1.335、1.204~1.524,P=0.002、<0.001、<0.001)。模型2将受试者年龄、糖尿病家族史、24~28孕周OGTT血糖指标升高项目进行多因素logistic回归分析结果显示,糖尿病家族史及24~28孕周OGTT 2项血糖指标(OGTT 1、2 h血糖)升高与3项血糖指标均升高,均为GDM患者产后AGM转归独立危险因素(OR=1.668、1.421、1.747,95%CI:1.192~2.333、1.035~1.952、1.195~2.553,P=0.003、0.030、0.004);24~28孕周仅FPG或OGTT 1 h血糖升高为其独立保护因素(OR=0.401、0.646,95%CI:0.240~0.670、0.418~0.997,P<0.001、=0.048)。结论对于GDM患者产后AGM转归,临床应关注其年龄、糖尿病家族史、孕期OGTT结果等指标。对GDM高危人群进行上述指标持续监测与规范干预,是健全GDM孕前-孕期-产后全程管理的重要环节。 相似文献