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31.
目的运用锥形束CT(CBCT)分析惠州市颌骨特发性骨硬化症(IO)的影像学特征。方法回顾性分析427例口腔疾病患者的CBCT影像学资料,观察颌骨IO的发病情况、分布情况、好发部位以及类型。结果 427例口腔疾病患者经CBCT发现36例颌骨IO,发病率为8.43%。所有颌骨IO皆为单发,男19例(52.78%),女17例(47.22%)。颌骨IO多发生于50~59岁,发病率为27.78%,不同年龄段患者颌骨IO发病率比较,差异无统计学意义(P>0.05)。颌骨IO发生于下颌34例,发生于上颌2例,好发于下颌前磨牙区,发生率为30.56%。颌骨IO的分类中V型、中央硬化型、根尖-骨皮质型均较高。结论 CBCT更能详细反映颌骨IO的形态及周围结构关系,一般无需治疗,但应该定期复查,一旦发现牙根吸收或对周围结构产生挤压等需进行干预。 相似文献
32.
Adaptation of the viral polymerase to host factors plays an important role in interspecies transmission of H5N1 viruses. Several adaptive mutations have been identified that, in general, determine not only host range, but also pathogenicity and transmissibility of the virus. The available evidence indicates that most of these mutations are found in the PB2 subunit of the polymerase. Particularly prominent mutations are located in the C-terminal domain of PB2 involving the amino acid exchanges E627K and D701N. Both mutations, that are also responsible for the adaptation of other avian viruses to mammalian hosts, have been described in human H5N1 isolates. In animal models, it could be demonstrated that they enhance pathogenicity in mice and induce contact transmission in guinea pigs. Mutation E627K has also been identified as a determinant of air-borne H5N1 transmission in ferrets. We are only beginning to understand the underlying mechanisms at the molecular level. Thus, mutation D701N promotes importin-α mediated nuclear transport in mammalian cells. Mutation E627K also enhances the replication rate in an importin-α dependent fashion in mammalian cells, yet without affecting nuclear entry of PB2. Numerous other adaptive mutations, some of which compensate for the lack of PB2 E627K, have been observed in PB2 as well as in the polymerase subunit PB1, the nucleoprotein NP, and the nuclear export protein NEP (NS2). 相似文献
33.
《Annals of human biology》2013,40(1):12-21
Background: The population of the island of Cres presents one of the few persisting Eastern Adriatic isolates and is thereby suitable for human population differentiation analyses.Aim: The aim of this study was to analyse the genetic structure of the island of Cres with respect to its eight sub-populations and to compare the genetic variation of the island of Cres with other Eastern Adriatic islands and the Croatian mainland.Subjects and methods: Fifteen AmpFlSTR identifiler loci were analysed in a sample group of 122 unrelated autochthonous individuals from the island of Cres, Croatia.Results: Analysis of STR polymorphisms revealed genetic homogeneity among sub-populations of the island of Cres and small but significant levels of genetic heterogeneity among geographically distant Eastern Adriatic islands.Conclusion: Despite a considerable degree of genetic homogeneity among the studied Eastern Adriatic islands, small but significant differentiation between distant islands indicates geographic sub-structuring which follows the isolation by distance model. This study is supportive of the notion that STR markers are useful for genetic differentiation between larger and geographically more distant regions. 相似文献
34.
Streptococcus suis (S. suis) serotype 2 usually cause infection in swine. Recently, two large-scale outbreaks in China with severe streptococcal toxic shock syndrome (STSS) and high mortality raised worldwide concern to human S. suis infection. To reveal the molecular pathogenesis of S. suis 2 during human infection, in-vivo induced antigen technology (IVIAT) was applied to identify the in-vivo induced genes (ivi genes) of S. suis 05ZYH33. The ivi genes are specifically expressed or up-regulated in-vivo and always associated with the in-vivo survival and pathogenicity of pathogens. In present study, convalescent sera from S. suis 05ZYH33 infected patients were pooled and fully adsorbed with in-vitro grown S. suis 05ZYH33 and Escherichia coli BL21 (DE3). Genomic expression library of 05ZYH33 was repeatedly screened with colony immunoblot assay using adsorbed sera. Finally, 19 genes were assessed as ivi genes of 05ZYH33. Fifteen of 19 genes encode proteins with biological functions in substance transport and metabolism, cell structure biogenesis, cell cycle control, replication, translation and other functions. The 4 remaining genes encode proteins with unknown functions. Of the 19 ivi genes, five (SSU05_0247, 0437, 1577, 1664 and 2144) encode proteins with no immunoreactivity to control sera from healthy individuals never exposed to 05ZYH33. The successful identification of ivi genes not only sheds light on understanding the pathogenesis of S. suis 05ZYH33 during its human infection, but also provides potential targets for the developments of new vaccines, therapeutic drugs and diagnostic reagents against human S. suis infection. 相似文献
35.
Alicia Zou Sudarshini Ramanathan Russell C. Dale Fabienne Brilot 《Cellular & molecular immunology》2021,18(2):294
Autoimmune neurological disorders, including neuromyelitis optica spectrum disorder, anti-N-methyl-D-aspartate receptor encephalitis, anti-MOG antibody-associated disorders, and myasthenia gravis, are clearly defined by the presence of autoantibodies against neurological antigens. Although these autoantibodies have been heavily studied for their biological activities, given the heterogeneity of polyclonal patient samples, the characteristics of a single antibody cannot be definitively assigned. This review details the findings of polyclonal serum and CSF studies and then explores the advances made by single-cell technologies to the field of antibody-mediated neurological disorders. High-resolution single-cell methods have revealed abnormalities in the tolerance mechanisms of several disorders and provided further insight into the B cells responsible for autoantibody production. Ultimately, several factors, including epitope specificity and binding affinity, finely regulate the pathogenic potential of an autoantibody, and a deeper appreciation of these factors may progress the development of targeted immunotherapies for patients. 相似文献
36.
陈传俊 陈伟良 孙长伏 何悦 蒋灿华 彭歆 尚政军 韩正学 李劲松 侯劲松 林李嵩 韩新光 魏建华 王志勇 吴煜农 郑家伟 李龙江 王慧明 李祖兵 郭传瑸 杨驰 石冰 张志愿 《中国口腔颌面外科杂志》2021,19(5):385-391
颏下岛状瓣(submental island flap, SMIF)是面动脉分支颏下动脉恒定供血的轴型皮瓣,与口腔颌面部缺损区相邻,其质地、色泽与头面部相似,血运充分。该组织瓣制备较简单,且成活率高,适用于修复口腔颌面部中型缺损。然而,国内外对于SMIF的应用仍然存在争议,主要集中在颈淋巴转移患者使用该皮瓣的肿瘤安全性、皮瓣的制备方法等方面。为统一和规范SMIF在口腔颌面-头颈部缺损修复中的应用,本文集中国内多家医学院校口腔颌面外科专家的智慧,达成专家共识,供同道参考。 相似文献
37.
38.
《The British journal of oral & maxillofacial surgery》2020,58(7):759-765
We evaluated the functional outcomes and health-related quality of life (HRQoL) of 117 patients (who had had primary operations for oral and oropharyngeal squamous cell carcinoma) using the University of Washington Quality of Life Questionnaire version 4 (UW- QOL V4), European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire version 3 (EORTC QLQ-C30 v3) and Head and Neck version 1 (EORTC H&N35 v1). The patients were divided into groups according to the reconstruction techniques used: primary closure, submental island pedicled flap (SIPF), and radial forearm free flap (RFFF). Patients who had reconstruction with RFFF had better HRQoL as measured by swallowing, mastication, speaking, and overall score, than the primary closure group (p < 0.05). There was no significant difference (p > 0.05) between the RFFF and SIPF groups in overall QOL one year postoperatively. The HRQoL of the SIPF group was also better than that of the primary closure group in terms of mastication, speaking, and loss of appetite. Swallowing, mastication, and speaking are major factors that affect the HRQoL of patients one year after operation for oral and oropharyngeal cancer. Flap reconstruction can improve patients’ QoL postoperatively. They can regain their ability to speak and swallow through training, and the importance of this issue must be addressed postoperatively. 相似文献
39.
目的 比较新的CpG岛甲基化表型(CIMP)筛选标记基因和经典CIMP筛选标记基因在CIMP肺癌筛选中的作用,并分析CIMP肺癌的临床病理特征.方法 取第二军医大学长海医院呼吸科50例肺癌患者的肺癌组织和癌旁组织,提取DNA,进行甲基化转换后,利用甲基化特异性PCR (MSP)对新的CIMP筛选标记基因(SHISA3、CTSL1、C1ORF103和TMEM200B)和经典的CIMP筛选标记基因(CACNA1G、IGF2、NEUROG1、RUNX3)的启动子CpG岛区域进行扩增,采用琼脂糖凝胶电泳分析其甲基化状态.运用SPSS统计软件对结果进行统计分析.结果 肺癌组织发生明显的甲基化,所研究的8个基因甲基化水平均明显高于癌旁组织(P=0.014).其中RUNX3甲基化与淋巴结转移及功能状态(PS)评分有关(P值分别为0.017、0.018).年龄>60岁的肺癌患者甲基化率高于≤60岁者(P=0.031).吸烟对CTSL1基因甲基化的影响也很大(P=0.018).结论 CpG岛甲基化表型肺癌具有独特的临床病理特征;新的和经典的甲基化基因组合在CIMP肺癌筛选上都具有较高的灵敏度和特异性. 相似文献
40.
【摘要】 目的 本研究利用基因工程技术全基因合成B型流感病毒冷适应株B/Yamagata/16/88的8个基因节段,并利用反向遗传技术从体外拯救B型流感病毒冷适应株B/Yamagata/16/88,同时建立BALB/c小鼠感染模型,为下一步研究B型流感病毒致病机制、传播机制以及开发新型疫苗奠定基础。方法 通过基因合成和反向遗传技术体外拯救B型流感病毒冷适应株B/Yamagata/16/88。全基因组测序验证拯救病毒基因组序列与Genbank序列的一致性。将拯救病毒以105EID50的攻毒剂量人工感染BALB/c小鼠,通过体重变化、生存率、肺脏病毒复制等方面进行致病性分析,建立小鼠感染模型。结果 成功从体外拯救出B型流感病毒冷适应株B/Yamagata/16/88,命名为B-S9。全基因组测序结果表明,B-S9基因组序列与Genbank公布序列一致。B-S9能够人工感染BALB/c小鼠,但不致死,对BALB/c小鼠呈现低致病性; 攻毒后第3天,B-S9感染小鼠体重出现下降,攻毒后第8天,小鼠体重开始回升;攻毒后第3天和第6天,B-S9感染小鼠的肺脏内均能检测到病毒复制,且攻毒后第3天的小鼠肺脏病毒滴度比攻毒后第6天的小鼠肺脏滴度高132倍。结论 成功搭建B型流感病毒冷适应株B/Yamagata/16/88反向遗传操作平台,并建立BALB/c小鼠感染模型。目前国内外对B型流感病毒的研究还较少,该反向遗传操作平台的建立为B型流感病毒致病机制和传播机制的研究奠定了基础,同时也为包括B型流感病毒减毒活疫苗在内的新型疫苗的研制开辟了新途径。 相似文献