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991.
Guangqiang Ye Hongyang Liu Qiongqiong Zhou Xiaohong Liu Li Huang Changjiang Weng 《Viruses》2022,14(3)
The non-specific innate immunity can initiate host antiviral innate immune responses within minutes to hours after the invasion of pathogenic microorganisms. Therefore, the natural immune response is the first line of defense for the host to resist the invaders, including viruses, bacteria, fungi. Host pattern recognition receptors (PRRs) in the infected cells or bystander cells recognize pathogen-associated molecular patterns (PAMPs) of invading pathogens and initiate a series of signal cascades, resulting in the expression of type I interferons (IFN-I) and inflammatory cytokines to antagonize the infection of microorganisms. In contrast, the invading pathogens take a variety of mechanisms to inhibit the induction of IFN-I production from avoiding being cleared. Pseudorabies virus (PRV) belongs to the family Herpesviridae, subfamily Alphaherpesvirinae, genus Varicellovirus. PRV is the causative agent of Aujeszky’s disease (AD, pseudorabies). Although the natural host of PRV is swine, it can infect a wide variety of mammals, such as cattle, sheep, cats, and dogs. The disease is usually fatal to these hosts. PRV mainly infects the peripheral nervous system (PNS) in swine. For other species, PRV mainly invades the PNS first and then progresses to the central nervous system (CNS), which leads to acute death of the host with serious clinical and neurological symptoms. In recent years, new PRV variant strains have appeared in some areas, and sporadic cases of PRV infection in humans have also been reported, suggesting that PRV is still an important emerging and re-emerging infectious disease. This review summarizes the strategies of PRV evading host innate immunity and new targets for inhibition of PRV replication, which will provide more information for the development of effective inactivated vaccines and drugs for PRV. 相似文献
992.
Linlin Ma Zhujing Ye Yarui Zhang Wenyu Shi Jingdong Wang Hongying Yang 《Journal of radiation research》2022,63(2):192
Radiation-induced neurocognitive dysfunction (RIND) has attracted a lot of attention lately due to the significant improvement of the survival of cancer patients after receiving cranial radiotherapy. The detailed mechanisms are not completely understood, but extensive evidence supports an involvement of the inhibition of hippocampal neurogenesis, which may result from radiation-induced depletion of neural stem cells (NSCs) as well as the damage to neurogenic niches. As an important component of neurogenic niches, vascular cells interact with NSCs through different signaling mechanisms, which is similar to the characteristics of radiation-induced bystander effect (RIBE). But whether RIBE is involved in neurogenesis inhibition contributed by the damaged vascular cells is unknown. Thus, the purpose of the present study was to investigate the occurrence of RIBEs in non-irradiated bystander NSCs induced by irradiated bEnd.3 vascular endothelial cells in a co-culture system. The results show that compared with the NSCs cultured alone, the properties of NSCs were significantly affected after co-culture with bEnd.3 cells, and further change was induced without obvious oxidative stress and apoptosis when bEnd.3 cells were irradiated, manifesting as a reduction in the proliferation, neurosphere-forming capability and differentiation potential of NSCs. All these results suggest that the damaged vascular endothelial cells may contribute to neurogenesis inhibition via inducing RIBEs in NSCs, thus leading to RIND. 相似文献
993.
994.
目的:探讨涎腺腺泡细胞癌(AciCC)的临床病理特征及与生物学行为相关的病理因素。方法 :收集1988—2011年,四川大学华西口腔医院的腺泡细胞癌病例68例,进行临床病理学分析和随访调查。结果:平均发病年龄为44.4岁,20岁以下4例(5.9%),男女比例为1∶1.13;就诊平均病程为45.2个月。肿瘤发生于腮腺为57例(83.8%)、腭部为4例(5.9%)、颊部为3例(4.4%)、颌下腺为2例(2.9%)。68例AciCC中,56例获随访信息,随访率为82.4%。复发率为26.5%,颈部淋巴结转移率为8.82%,5年生存率为98.21%。肿瘤间质中有大量淋巴样细胞浸润的患者,复发率较低(P<0.05)。结论:AciCC肿瘤间质中大量淋巴样细胞浸润,是提示患者预后较好的一个病理指标。 相似文献
995.
目的探究微孔钛网在犬下颌牙槽骨增量术中的作用效果。方法选择6只成年健康杂种犬,建立双侧下颌牙槽骨缺损动物模型。将每只犬的左侧下颌牙槽骨缺损区作为第Ⅰ组,右侧作为第Ⅱ组。两组均采用GBR+自体骨修复牙槽骨缺损,第Ⅰ组采用微孔钛网,第Ⅱ组采用海奥口腔修复膜。观察植骨术后4周、8周、12周时两组大体标本、Masson染色、HE染色、荧光素标记、CT三维重建后骨微结构参数的结果。结果术后12周第Ⅰ组及第Ⅱ组植骨区域表面均形成明显新生软骨组织,移植骨与原骨之间界限模糊,其中第I组新生成骨面积略大于第Ⅱ组,新生成骨形态略优于第Ⅱ组,其它方面大体标本上肉眼观察结果差异不明显,两组牙槽嵴高度比较也无显著差异(P>0.05)。Masson染色及HE染色显示两组均有明显新生骨组织、骨小梁生成。术后12周两组骨矿化率比较无显著差异(P>0.05)。术后12周两组骨小梁数量、骨小梁厚度、骨体积比较也无显著差异(P>0.05)。结论微孔钛网在犬下颌牙槽骨缺损的GBR手术中能获得良好成骨效果,临床中可根据患者具体情况,合理应用。 相似文献
996.
目的 统计分析四川地区成年人群中分叉下颌管发生概率,并总结下颌管各分叉类型及发生率与走行方式和各自形态特征。方法 根据纳入和排除标准收集500例患者(共计1 000侧下颌骨)的锥形束CT(CBCT)影像资料,对所收集的资料进行观察分析,并记录数据,对下颌神经管分支的类型及其特征进行归纳和分类。结果 500例患者中分叉下颌管的发生率为13.8%(69/500),共发生于92侧(9.2%)的下颌骨中。其中最常见的类型为磨牙后管,其次为向牙根及颊舌向分支,最少见的类型为向前走行的分支。分支的平均直径和长度分别为0.90、9.39 mm。结论 本研究使用CBCT作为研究手段,得出的分叉下颌管在四川地区成年人群中的发生率要明显高于以前报道的使用全景片作为研究手段的研究;并且CBCT对下颌管及其分支的三维走行及形态特征的表现能力优于全景片。 相似文献
997.
目的:通过对阻塞性睡眠呼吸暂停低通气综合征(obstructive sleep apnea hypopnea syndrome,OSAHS)患者的颞下颌关节(temporomandibular joint,TMJ)行磁共振扫描分析,探讨OSAHS患者与正常人群颞下颌关节形态的差异.方法:选取2014年1月-2016年5月收治的18例OSAHS患者和18例健康成人,分别记为研究组和对照组;按照呼吸暂停及低通气指数(apnea and hypopnea index,AHI),将OSAHS患者分为轻、中、重3个亚组(n=6).对所有纳入人群行TMJ的MRI扫描并测量关节间隙,采用SPSS 17.0软件包对测量数据进行统计学处理.结果:2组患者在年龄、性别构成、关节上间隙及髁突有无移位方面差异均无显著性(P>0.05).OSAHS患者TMJ左侧前间隙[(2.61±0.19)mm:(2.47±0.18)mm,P<0.05]、右侧前间隙[(2.63±0.18)mm:(2.48±0.17)mm,P<0.0S]大于正常人群.OSAHS患者TMJ左侧后间隙[(2.43±0.20)mm:(2.51±0.19)mm,P<0.05]、右侧后间隙[(2.44±0.20)mm:(2.60±0.13)mm,P<0.05]小于正常人群.轻度OSAHS组TMJ左侧前间隙[(2.53±0.26)mm:(2.73±0.07) mm,P<0.05]、右侧前间隙[(2.54±0.11)mm:(2.74±0.14)mm,P<0.05]均小于重度组;轻度OSAHS组TMJ左侧后间隙[(2.56±0.29)mm:(2.29±0.09)mm,P<0.05]、右侧后间隙[(2.55±0.23) mm:(2.31±0.09)mm,P<0.05]均大于重度组.结论:OSAHS患者的髁突相比正常人群处于关节窝偏后位置.髁突位于关节窝偏后位置的趋势与OSAHS的严重程度相关. 相似文献
998.
目的:探讨钛表面锌元素注入沉积改性后,材料表面的化学组成及其对变形链球菌黏附和形态的影响。方法:应用全方位离子注入与沉积技术,对纯钛试件表面进行锌元素注入沉积,通过X射线光电子能谱分析,研究其表面化学组成及各元素百分比;将变形链球菌接种于锌元素注入沉积前、后不同注入沉积时间组的钛样品表面,扫描电镜观察细菌在其表面黏附数量和菌体形态的变化。采用SPSS13.0软件包中的单因素方差分析对数据进行统计学分析。结果:XPS全谱图显示,锌元素注入沉积改性后,样品由钛、氧、锌和碳元素组成。随着锌元素注入沉积时间的延长,材料表面锌元素含量增高;变形链球菌相应减少,各实验组(Zn-Ti)与商业纯钛组(cp-Ti)间均有显著差异(P<0.01);各实验组间差异显著(P<0.05),菌体未见明显变化。结论:全方位锌离子注入沉积技术可使纯钛表面形成含有锌离子的改性层,并增加了抗变形链球菌的黏附功能。 相似文献
999.
目的:评价前牙区直接法纤维增强复合桥(FRC bridge)修复单颗切牙缺失伴邻牙松动的牙周炎病例临床应用效果。方法:采用直接法FRC bridge连接所有同颌前牙修复单颗切牙缺失伴邻牙松动的牙周炎病例12例,以弹性义齿修复14例同类病例作为对照,修复后1、6及18个月随访,对临床修复效果以及牙周状况进行评价。结果:修复后1、6或18个月,直接法FRC bridge修复组和对照组解剖外形和边缘适应性均优于弹性义齿修复组(P<0.05);牙周袋探诊深度(PD)及探诊出血指数(BOP)随着观察时间延长而逐渐减小;修复前后PD、BOP、牙齿松动度(TM)差异均存在显著性(P<0.05)。结论:直接法FRC bridge修复单颗切牙缺失伴邻牙松动的牙周炎病例,能达到良好的临床美学修复效果,并可改善邻牙牙周状况。 相似文献
1000.
Chujia Liang Jing Cheng Shaoqian Chen Zhuangjian Ye Fan Zhang 《Hematology (Amsterdam, Netherlands)》2018,23(2):65-76
Background: Although dysplasia plays an important role in the diagnosis of myelodysplasia syndrome (MDS), its morphologic variety and irregularity result in difficulties in its clinical application.Methods: Bone marrow smears from cases with MDS and non-clonal disease were collected and performed microscopy analysis. We respectively recorded the percentage of specific dysplastic cells (PSDC) and incidence of specific dysplasia (ISD) of each dysplastic type in three hematopoietic cell lineages for the comprehensive analysis of diagnostic efficacy to MDS.Results: Compared with non-clonal anemia, the PSDCs and ISDs of the four specific dysplastic types as petal nucleus and internuclear bridging in erythroid lineage, pseudo-Pelger-Huet in granulocytic lineage and lymphoid small megakaryocyte in megakaryocytic lineage were significantly higher in MDS; and their area under the curves were all greater than 0.600. If the dysplastic rate in each lineage was higher than 10%, their corresponding false positive rates (FPRs) were below 0.033, 1?×?10?4 and 1?×?10?4, respectively. If the dysplastic rates in three cell lineages reached 0.065, 0.045 and 0.040, respectively, their corresponding FPRs were all below 0.050.Conclusion: Four specific dysplastic types possess higher diagnostic efficacy for the diagnosis of MDS. Though the dysplastic rate over 10% in any hematopoietic cell lineage presents a lower FPR, it is possibly considered to lower the diagnostic threshold of MDS if a specific dysplastic type with higher diagnostic efficacy presents. 相似文献