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31.
The granuloma formation is a host defense response against persistent irritants. Osteopontin is centrally involved in the formation of granulomas. Three osteopontin alleles, designated a, b, and c, have been found in mice. Here we used a murine model of zymosan (beta-glucan)-induced granuloma formation in the liver to determine possible functional differences between the osteopontin alleles in cell-mediated immunity. In contrast to mice with alleles a or c, mice with the allele b was defective in granuloma formation. As detected by mRNA expression, cytokines and chemokines known to be critically involved in granuloma formation were elicited in liver tissue, regardless of the osteopontin allele expressed. Alignment of the deduced amino acid sequences showed that unlike osteopontin c, b differs from a in 11 amino acids. All three osteopontin alleles had normal cell-binding properties. However, only the b allelic form was defective in the induction of cell migration as tested with dendritic cells. In conclusion, generation of a granulomatous response in mice depends critically on the presence of a functional osteopontin allele. Defective granuloma formation in mice with allele b is likely to be because of an impaired chemotactic function of the osteopontin b protein on immunocompetent cells.  相似文献   
32.
Yu F  Wang H  Qian H  Kaushik R  Bownes M  Yang X  Chia W 《Genes & development》2005,19(11):1341-1353
Heterotrimeric G proteins mediate asymmetric division of Drosophila neuroblasts. Free Gbetagamma appears to be crucial for the generation of an asymmetric mitotic spindle and consequently daughter cells of distinct size. However, how Gbetagamma is released from the inactive heterotrimer remains unclear. Here we show that Locomotion defects (Loco) interacts and colocalizes with Galphai and, through its GoLoco motif, acts as a guanine nucleotide dissociation inhibitor (GDI) for Galphai. Simultaneous removal of the two GoLoco motif proteins, Loco and Pins, results in defects that are essentially indistinguishable from those observed in Gbeta13F or Ggamma1 mutants, suggesting that Loco and Pins act synergistically to release free Gbetagamma in neuroblasts. Furthermore, the RGS domain of Loco can also accelerate the GTPase activity of Galphai to regulate the equilibrium between the GDP- and the GTP-bound forms of Galphai. Thus, Loco can potentially regulate heterotrimeric G-protein signaling via two distinct modes of action during Drosophila neuroblast asymmetric divisions.  相似文献   
33.
目的 为了观察儿童自身免疫病患者 (以SLE为代表 )在应用地塞米松 2 4h前后细胞凋亡情况 ,对其外周血淋巴细胞早期凋亡率进行了检测。方法 应用最新的AnnexinV检测试剂盒及流式细胞仪检测早期凋亡细胞。结果 儿童SLE初发活动期患者外周血淋巴细胞早期凋亡率 (2 .36 6± 1.5 34% )明显低于经静脉注射地塞米松 2 4h后的患儿 (10 .6 96±2 .830 % )及同年龄段正常儿童 (12 .4 95± 2 .4 78% ) ;而后两者相比则无明显差异。结论 儿童SLE活动期患者经过静脉注射地塞米松以后 ,外周血淋巴细胞凋亡率明显升高。其可能的机制为固醇类激素通过激活促进凋亡基因 ,从而促进大量淋巴细胞凋亡 ,使自身免疫病的发生受到控制。  相似文献   
34.
Background: Investigation of haplotype/allele frequency data of Y-STR loci in ethnically diverse populations is essential for forensic reference database construction and genetic application. However, the population genetic characteristics of the Chinese Miao minority from Guizhou Province remain uncharacterised.

Aim: To assess forensic characteristics for 23 Y-Chromosomal STR loci in Guizhou Miao and explore population genetic relationships with geographically neighbouring populations.

Subjects and methods: Twenty-three Y-Chromosomal STRs were genotyped using the Powerplex® Y23 system in 103 unrelated Chinese Miao males from Guizhou Province, southwest China. Haplotypes and forensic parameters were obtained. Population relationships of Guizhou Miao with others were revealed using AMOVA and an MDS plot.

Results: A total of 96 haplotypes were identified with overall haplotype diversity (HD) and discrimination capacity (DC) of 0.9985 and 0.9320, respectively. Genetic differentiation was observed with most of the comparison populations, prominently for Guizhou Shui.

Conclusion: The 23 Y-STR loci were highly polymorphic and discriminating in the Guizhou Miao population and could be used for forensic practice and population genetic studies. Population relationship analysis revealed Guizhou Miao had a close genetic relationship with geographically close Guizhou Gelao, as well as Han majorities derived from different regions.  相似文献   

35.
Infantile anaemia has been a severe public health problem in China for decades. However, it is unclear whether there are regional differences in the prevalence of anaemia. In this study, we used data from the China Nutrition and Health Surveillance (CNHS) to assess the prevalence of anaemia and the risk factors associated with its prevalence in different regions. We included 9596 infants aged 0–23 months from the CNHS 2013 database. An infant was diagnosed with anaemia if he/she had a haemoglobin concentration of <110 g/L. We used multivariate logistic regression to investigate the potential risk factors associated with the development of anaemia. We found that anaemia was present in 2126 (22.15%) of the infants assessed. Approximately 95% of these cases were classified as mild anaemia. Based on the guidelines laid out by the World Health Organization, 5.5% and 43.6% of the surveillance sites were categorized as having severe and moderate epidemic levels of anaemia, respectively. The prevalence of infantile anaemia in Eastern, Central and Western China was 16.67%, 22.25% and 27.44%, respectively. Premature birth, low birth weight, breastfeeding and residence in Western China were significantly associated with higher odds of developing anaemia. Female sex and having mothers with high levels of education and maternal birth age >25 years were associated with lower odds of developing anaemia. In conclusion, we observed significant regional disparities in the prevalence of infantile anaemia in China. Western China had the highest prevalence of infantile anaemia, and rural regions showed a higher prevalence of anaemia than urban regions.  相似文献   
36.
目的通过对北京市5年先天性脑积水(CH)监测资料分析,了解北京市胎儿及婴儿的CH发生率、诊断及转归。 方法选择2015年1月至2019年12月,北京市出生缺陷监测系统内监测对象(胎龄为13周至生后1岁)中,407例CH患儿(胎儿或婴儿)为研究对象。对其出生缺陷诊断资料进行分析。采用χ2检验,对孤立性与非孤立性CH活产儿婴儿期存活率进行统计学比较。本研究遵循的程序符合2013年新修订的《世界医学协会赫尔辛基宣言》要求。 结果本研究时间(5年)内,北京市胎儿及1岁内婴儿的CH发生率为3.60×10-4(407/1 129 861)。这407例CH患儿中,82例(20.15%)合并颅外畸形,20例(4.91%)合并染色体异常;CH胎儿的产前诊断率为92.38%(376/407),超声检出CH胎儿时,其胎龄为24周(23~35周),其中胎龄≥28周者占26.06%(98/376)。376例产前被诊断的CH胎儿中,44例采取产前胎儿超声联合MRI检查,而且通过胎儿MRI检查对4例胎儿的颅内畸形具体类型进行了补充诊断。本研究未发现CH患儿的孕母合并宫内感染;103例CH活产儿中,73例孤立性CH患儿的婴儿期(1岁内)存活率为72.6%(53/73),高于30例非孤立性CH患儿的婴儿期存活率(60.0%,18/30),二者比较,差异无统计学意义(P>0.05)。 结论北京市在预防出生缺陷发生的三级防控体系中,对CH胎儿与婴儿的一级、二级防控已取得效果。对孕妇全孕期多次动态胎儿超声检查,必要时联合胎儿MRI检查,对非孤立性CH胎儿同时采取细胞遗传学和分子遗传学检测,可进一步提高CH患儿的防控效果。  相似文献   
37.
目的 了解郑州市新型冠状病毒肺炎患者定点收治医院护理人员的心理状况,从而为应对突发公共卫生事件医务人员的心理卫生、心理干预咨询提供参考的理论依据及指导.方法 选择本市新型冠状病毒肺炎疑似及确诊患者定点救治医院护理人员,共收集到462名护理人员信息,采用填写网络问卷SCL-90量表的方法进行调查,并与常模数据做对比,用SPSS19.0统计软件进行统计分析.结果 最终完成436名护理人员调查统计与分析,SCL-90量表总得分为(144.51±36.20),高于1986年全国常模(129.96±38.26)分以及2006年全国常模(130.021±33.626)分.其中,躯体化、强迫、抑郁、焦虑、恐怖因子分高于护士常模(P<0.05)及全国常模(P<0.05).结论 新型冠状病毒肺炎疫情期间,本市护理人员存在一定的心理压力.我们应注意到护理人员的心理压力以及引起压力的主要危险因素,并采取积极有效的方式应对,采取针对性措施进行疏导,减轻护理人员的心理压力,保证护理人员工作有效顺利进行.  相似文献   
38.
血清胆红素与冠脉病变程度及血脂的相关性分析   总被引:15,自引:4,他引:11  
目的分析血清胆红素与冠脉病变程度及血脂的关系。方法对冠状动脉造影术确诊的冠心病者和非冠心病者进行病例-对照研究。结果冠心病组血清胆红素水平低于非冠心病组,差异有显著性(P<0.05)。多元逐步回归分析血清直接胆红素进入回归方程,提示血清直接胆红素与冠脉病变程度呈独立负相关,其相关强度与甘油三脂(TG)和空腹血糖(FBS)相似。血清胆红素与血脂直线相关分析提示血清胆红素与甘油三脂、总胆固醇(TCHO)和低密度脂蛋白胆固醇(LDL-C)呈显著负相关。结论血清直接胆红素水平与冠脉病变程度呈独立负相关,低血清胆红素是冠状动脉粥样硬化的危险因素,血清胆红素与甘油三脂、总胆固醇和低密度脂蛋白胆固醇呈负相关。  相似文献   
39.
广东省绿头鸭场鸭乙肝病毒自然携带状况调查   总被引:1,自引:0,他引:1  
目的 调查两个鸭场携带乙肝病毒(DHBV)状况。方法 在对广东省家养绿头鸭分布状况进行系统调查的基础上,对南海市和顺镇、里水镇两个绿头鸭场作了随机抽样调查,采集了雏鸭、青年鸭和种鸭的血标本共519份,应用斑点分子杂交(DotBlot)测定法观察绿头鸭乙型肝炎病毒(DHBV)自然携带率。结果 两鸭场绿头鸭的DHBV自然携带率为36.0%(187/519),其95%可信限为31.0%~44.0%。不同鸭龄组绿头鸭DHBV自然携带比较,两鸭场同日龄绿头鸭DHBV自然携带率比较,绿头鸭DHBV自然携带率的性别比较,差异均无显著意义。不同鸭龄的绿头鸭DHBV-DNA含量定量分析(A值),差异有非常显著性(P<0.01),其含量由高到低顺序为雏鸭>种鸭>青年鸭,和顺鸭场的绿头鸭DHBV-DNA含量高于里水鸭场。结论 两鸭场绿头鸭携带的DHBV可能源于不同的亚株。  相似文献   
40.
目的探讨"互联网+护理服务"的研究现状、热点情况及发展趋势,以期为我国"互联网+护理服务"的持续健康发展提供参考。方法以中国知网作为检索源,选取主题为"互联网+护理服务"的文献,检索从建库至2020年7月31日发表的相关研究文献,使用文献计量学软件Citespace5.6.R5对文献进行计量分析。结果共检索出有效文献231篇,发文量整体呈上升趋势,研究方向多集中在单一护理领域,作者和机构间合作较少,热点关键词为延续护理、专科护士、临床护士、慢性病、老年人、养老服务、医师多点执业等,研究热点变化从临床护士、护理管理者、养老服务到专科护士、质性研究、伤口造口、信息化平台、慢性病等方向。结论"互联网+护理服务"日益受到研究者关注,但仍存在诸多问题。需加强"互联网+护理服务"研究的深度和广度,注重学科间、作者和机构间的交流与合作,拓展研究主题,从而使"互联网+护理服务"得到健康发展,为患者提供更好的护理服务。  相似文献   
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