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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
《Vaccine》2020,38(39):6141-6152
Influenza vaccination is considered the most valuable means to prevent and control seasonal influenza infections, which causes various clinical symptoms, ranging from mild cough and fever to even death. Among various influenza vaccine types, the inactivated subunit type is known to provide improved safety with reduced reactogenicity. However, there are some drawbacks associated with inactivated subunit type vaccines, with the main ones being its low immunogenicity and the induction of Th2-biased immune responses. In this study, we investigated the role of a single-stranded RNA (ssRNA) derived from the intergenic region in the internal ribosome entry site of the Cricket paralysis virus as an adjuvant rather than the universal vaccine for a seasonal inactivated subunit influenza vaccine. The ssRNA adjuvant stimulated not only well-balanced cellular (indicated by IgG2a, IFN-γ, IL-2, and TNF-α) and humoral (indicated by IgG1 and IL-4) immune responses but also a mucosal immune response (indicated by IgA), a key protector against respiratory virus infections. It also increases the HI titer, the surrogate marker of influenza vaccine efficacy. Furthermore, ssRNA adjuvant confers cross-protective immune responses against heterologous influenza virus infection while promoting enhanced viral clearance. Moreover, ssRNA adjuvant increases the number of memory CD4+ and CD8+ T cells, which can be expected to induce long-term immune responses. Therefore, this ssRNA-adjuvanted seasonal inactivated subunit influenza vaccine might be the best influenza vaccine generating robust humoral and cellular immune responses and conferring cross-protective and long-term immunity. 相似文献
42.
S. Natoli V. Oliveira P. Calabresi L. F. Maia A. Pisani 《European journal of neurology》2020,27(9):1764-1773
The current coronavirus disease (COVID‐19) outbreak, caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2), has raised the possibility of potential neurotropic properties of this virus. Indeed, neurological sequelae of SARS‐CoV‐2 infection have already been reported and highlight the relevance of considering the neurological impact of coronavirus (CoV) from a translational perspective. Animal models of SARS and Middle East respiratory syndrome, caused by structurally similar CoVs during the 2002 and 2012 epidemics, have provided valuable data on nervous system involvement by CoVs and the potential for central nervous system spread of SARS‐CoV‐2. One key finding that may unify these pathogens is that all require angiotensin‐converting enzyme 2 as a cell entry receptor. The CoV spike glycoprotein, by which SARS‐CoV‐2 binds to cell membranes, binds angiotensin‐converting enzyme 2 with a higher affinity compared with SARS‐CoV. The expression of this receptor in neurons and endothelial cells hints that SARS‐CoV‐2 may have higher neuroinvasive potential compared with previous CoVs. However, it remains to be determined how such invasiveness might contribute to respiratory failure or cause direct neurological damage. Both direct and indirect mechanisms may be of relevance. Clinical heterogeneity potentially driven by differential host immune‐mediated responses will require extensive investigation. Development of disease models to anticipate emerging neurological complications and to explore mechanisms of direct or immune‐mediated pathogenicity in the short and medium term is therefore of great importance. In this brief review, we describe the current knowledge from models of previous CoV infections and discuss their potential relevance to COVID‐19. 相似文献
43.
目的采用网络药理学和分子对接法分析款冬花在清肺排毒汤治疗新型冠状病毒肺炎(COVID-19)中发挥的作用。方法基于课题组前期研究,确定款冬花中的主要成分。采用SwissTargetPrediction和BATMAN-TCM数据库对款冬花主要化学成分的潜在靶点进行整理;在GenCLiP 3和GeneCard数据库搜索COVID-19相关靶点,运用Cytoscape 3.7.1软件绘制款冬花成分-靶点-疾病网络图;使用String数据库构建靶点PPI网络;通过DAVID数据库进行GO富集分析和KEGG通路富集分析;将各成分与新型冠状病毒(SARS-CoV-2)3CL水解酶和血管紧张素转化酶II(ACE2)进行分子对接。结果款冬花治疗COVID-19的化合物-靶点-疾病网络包含化合物14个、靶点104个、疾病4个。GO功能富集分析得到GO条目444个(P0.05),其中包括生物过程(BP)条目325个、细胞组成(CC)条目44个、分子功能(MF)条目75个。KEGG通路富集筛选得到94条信号通路(P0.05)。分子对接结果显示异绿原酸B(3,4-dicaffeoylquinicacid)和异绿原酸C(4,5-dicaffeoylquinic acid)与蛋白的亲和力要优于瑞德西韦。结论款冬花中主要化合物能通过与SARS-Co V-2 3CL水解酶和ACE2结合,作用于多靶点调节多条信号通路,从而发挥对COVID-19的防治作用。 相似文献
44.
Eric W. Dickson MD Gary V. Doern PhD Leo Trevino PhD Michelle Mazzoni PhD Stephen O. Heard MD 《Academic emergency medicine》2003,10(10):1019-1023
OBJECTIVES: Patients undergoing emergent endotracheal intubation are at increased risk for developing pneumonia. Although numerous strategies have been investigated to reduce ventilator-associated pneumonia (VAP), the incidence of VAP and its associated mortality remains high. This investigation tested the hypothesis that LiquiVent (Alliance Pharmaceutical, San Diego, CA-LV) delivered antibiotics (via spray-dried microspheres-SDM) would improve survival in a rat model of descending gram-negative pneumonia. METHODS: Wistar rats (n = 49) were randomized to receive prophylaxis with 1). nothing (controls); 2). intramuscular (IM) tobramycin, 3). intratracheal LV plus SDM shells (vehicle), 4). intratracheal LV plus SDM shells plus IM tobramycin, or 5). intratracheal LV plus SDM containing 1 mg/kg of tobramycin. All interventions were given 24 hours before a bacterial challenge with 10(8) colony-forming units of intratracheal Klebsiella pneumoniae. Mortality at ten days was the sole outcome measure. Survival in individual groups was compared with controls by Fisher's exact test with Bonferroni correction for multiple comparisons. RESULTS: All animals in the control group died of pneumonia within ten days of bacterial inoculation (0% survival). Prophylaxis with either IM tobramycin or SDM vehicle plus IM tobramycin provided no protection (0% survival). This is in sharp contrast to the cohort receiving pretreatment with tobramycin-containing SDM delivered via LV, in which 60% of the animals survived to study completion (p < 0.05). CONCLUSIONS: Prophylaxis with SDM containing antibiotics delivered in low-dose LV provided significant protection in a rat model of descending gram-negative pneumonia. These data support the hypothesis that perfluorocarbon-delivered intratracheal antimicrobials may be useful in the prevention of VAP. 相似文献
45.
暴发流行的肺炎衣原体肺炎影像学表现分析 总被引:1,自引:0,他引:1
目的研究肺炎衣原体肺炎暴发流行的胸部影像学特征表现。方法对经过痰和咽试子标本,PCR,MIF检测证实的15例暴发流行的肺炎衣原体肺炎住院患者胸部X线和高分辨CT表现进行分析。结果本组暴发流行的肺炎衣原体肺炎患者均有发热,头痛,全身肌肉酸痛,干咳,声音嘶哑,咽痛等症状。肺部呼吸音减低或细湿啰音4例(26.7%),出现明显肺部影像学表现10例(66.7%)。10例暴发流行的肺炎衣原体肺炎常表现为多发或单发以小叶为中心阴影和腺泡状结节影(100%),病变以两中、下肺叶,外、中带分布;以小叶分布的气腔实变和磨玻璃样阴影(分别为100%和40%)和支气管血管束增厚(90%)。无肺门或纵隔淋巴结增大和胸腔积液。结论暴发流行的肺炎衣原体肺炎具有群体发病,临床和影像学表现有相似的特征,早期CT检查更能真实地反映病变大小、多少和分布范围。 相似文献
46.
47.
黄连解毒汤对高胆固醇兔血液流变学和动脉粥样硬化干预作用 总被引:3,自引:0,他引:3
目的:观察黄连解毒汤对肺炎衣原体(Cpn)感染后高胆固醇饮食兔血液流变学和动脉粥样硬化的影响.方法:造模前60只新西兰兔经采血检测Cpn IgG均为阴性.随机选取8只兔作正常组,其余52只以含2.5 g·kg~(-1)胆固醇的饲料喂养并接种Cpn.经检测血清Cpn IgG阳性者随机分为4组:黄连解毒汤高、低剂量(3.34,1.67 g·kg~(-1)·d~(-1))组、阳性药阿奇霉素(20 mg·kg~(-1)·d~(-1))组和模型组(生理盐水),每组11只,灌胃给药6周;Cpn IgG阴性者作高胆固醇组,不予药物干预.治疗结束后采血测定高、中、低全血黏度、血浆黏度和红细胞压积,并计算RBC聚集指数、变形指数和刚性指数;取主动脉弓近左颈总动脉分叉处血管,测定和计算最大血管内膜厚度(MIT)、动脉粥样硬化病变占管周百分比(P_(LCI))、动脉粥样硬化斑块面积指数(Ⅰ_(PA)).结果:高胆固醇组和模型组血液流变学均显著紊乱,主动脉均有典型的动脉粥样硬化病理变化,后者最大MIT(23.65±8.19 vs 12.76±4.06)μm、动脉粥样硬化病变P_(LCI)(41.08±12.51 vs 22.43±9.45)%、动脉粥样硬化斑块Ⅰ_(PA)(9.57±1.82 vs 2.84±0.25)%显著较前者高(均P<0.01);黄连解毒汤高、低剂量组、阿奇霉素组血液流变学紊乱和动脉粥样硬化病理变化与模型组比较显著改善,其中黄连汤高剂量组MIT(6.45±1.27 vs 23.65±8.19),(P<0.01),P_(LCI),(22.39±6.74 vs41.08±12.51),(P<0.05);Ⅰ_(PA)(1.44±0.33 vs 9.57±1.82),(P<0.01)显著降低.结论:Cpn感染加重高胆固醇饮食兔血液流变学紊乱和动脉粥样硬化损害,黄连解毒汤可减轻Cpn感染所致高胆固醇饮食兔的血液流变学紊乱和动脉粥样硬化损害. 相似文献
48.
49.
68例社区获得性肺炎病原及临床特征分析 总被引:5,自引:3,他引:2
目的 68例外周血白细胞正常或降低的社区获得性肺炎 (CAP)病原及临床特点分析。方法 检测CAP患者呼吸道及血液标本的常见病原体 ,并分析其临床特点。结果 军团菌属占 2 2 .1 % (1 5/ 68) ,肺炎支原体占 1 1 .8% (8/ 68) ,病毒占 1 6 .2 % (1 1 / 68) ,其中甲型流感病毒 2例、乙型流感病毒 5例 ,副流感病毒 1例 ,腺病毒 1例 ,艾滋病病毒 2例。细菌占 2 .9% (2 / 68) ,有 47.1 % (32 / 68)不能明确病原体 ,混合感染率为 8.8% (6/ 68)。病毒性肺炎、军团菌肺炎及肺炎支原体肺炎的临床症状、体征、外周血白细胞、胸部影像均无特异性 ,其鉴别需靠病原学检查。结论 外周血白细胞正常或降低的CAP病因主要为非典型病原体和病毒 ,对此类CAP的经验治疗应首选大环内酯类抗生素或抗病毒药物。 相似文献
50.
94例有肺外并发症的儿童肺炎支原体肺炎临床分析 总被引:3,自引:3,他引:0
目的探讨肺炎支原体肺炎(myeoplasma pneumoniae pneumonia,MPP)临床、肺外并发症和诊治。方法对94例确诊为MPP患儿进行回顾性分析。结果发病多集中在学龄前及学龄儿童,3~10岁55例(58.4%),发热69例(73.4%),持续性咳嗽80例(85.1%),多数肺部可闻及干啰音,胸片呈斑点状阴影41例,呈阶段性肺炎26例,呈间质性损害16例,表现肺门影增浓11例,大多患者(84.0%)外周血白细胞总数正常,血红蛋白低于正常值29例,全部病例均有肺外并发症,72例静脉使用红霉素,后改阿奇霉素口服治疗,47例痊愈。结论MPP好发学龄前及学龄儿童,其肺外并发症常见,红霉素、阿奇霉素序贯治疗安全、疗效满意。 相似文献