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《Vaccine》2015,33(41):5365-5370
Current live attenuated vaccines for control of Salmonella in poultry persist in the ceca and may persist in the environment. In this paper we report the construction and characterization of the vaccine efficacy of a Salmonella mutant strain with inducible mviN expression and rapid clearance from the host. The mutant was effective in oral immunization of the broiler chicken host against a virulent Salmonella oral challenge strain, having a mean 7 × 106 CFU/g in the ceca of unvaccinated controls compared to a mean 2 × 103 CFU/g in the ceca of vaccinated chickens at 4 weeks post-challenge (6 weeks of age). The mutant strain also demonstrated immunogenicity, reduced organ colonization, and rapid clearance in broiler chickens within 3 weeks of inoculation. 相似文献
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《中国现代医生》2020,58(31):37-39+封三
目的 探讨脂蛋白相关磷脂酶A2(Lp-PLA2)、胰岛素样生长因子-1(IGF-1)与老年血管性痴呆(VD)患者认知功能的关系及预测价值。方法 选择2019 年3~6 月在我院接受治疗的VD 患者60 例为研究对象,同时选取同期在我院接受检查的健康者60 例为对照组,比较两组患者的Lp-PLA2、IGF-1、简易智力状态检查量表评分(MMSE)水平;采用Pearson 相关性分析法对Lp-PLA2、IGF-1 与MMSE 评分的相关性进行分析;采用受试者工作曲线(ROC)下面积(AUC)比较Lp-PLA2、IGF-1 对VD 的预测价值。结果 观察组患者的Lp-PLA2 水平明显高于对照组(P<0.05),观察组患者的IGF-1、MMSE 评分明显低于对照组(P<0.05);Lp-PLA2 与MMSE 评分呈负相关性,IGF-1 与MMSE 评分呈正相关性;Lp-PLA2 与IGF-1 诊断VD 的AUC 值分别为0.940、0.954。结论Lp-PLA2 水平越低,IGF-1 水平越高,患者的认知功能越好,且Lp-PLA2、IGF-1 对老年VD 患者均具有较高的预测价值。 相似文献
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《Enfermería intensiva / Sociedad Espa?ola de Enfermería Intensiva y Unidades Coronarias》2020,31(2):82-89
In January 2020, the Chinese authorities identified a new virus of the Coronaviridae family as the cause of several cases of pneumonia of unknown aetiology. The outbreak was initially confined to Wuhan City, but then spread outside Chinese borders. On 31 January 2020, the first case was declared in Spain. On 11 March 2020, The World Health Organization (WHO) declared the coronavirus outbreak a pandemic. On 16 March 2020, there were 139 countries affected. In this situation, the Scientific Societies SEMICYUC and SEEIUC, have decided to draw up this Contingency Plan to guide the response of the Intensive Care Services. The objectives of this plan are to estimate the magnitude of the problem and identify the necessary human and material resources. This is to provide the Spanish Intensive Medicine Services with a tool to programme optimal response strategies. 相似文献
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Inflammation plays a critical role in the development of ventilator-induced lung injury (VILI). Endoplasmic reticulum (ER) stress is associated with a variety of diseases through the modulation of inflammatory responses. However, little is known about how ER stress is implicated in VILI. In this study, murine mechanical ventilation models were constructed. Total protein and inflammatory cytokines were measured in bronchoalveolar lavage fluid (BALF), and lung tissue injury was assessed by histology. Our data revealed that mice subjected to high tidal ventilation (TV) for 4 h showed more severe pulmonary edema and inflammation than those of mice with spontaneous breathing and low TV-treatment. In addition, the high TV-treated animals upregulated the ER stress markers GRP78, CHOP, p-IRE1α, TRAF2, and p-NF-κB expression at both the mRNA and protein levels in lung tissue. Administration of thapsigargin exacerbated the histological changes, inflammation and expression of GRP78 and CHOP after high TV, but treatment with ER stress and IRE1α kinase inhibitors attenuated the pathological damage and downregulated the high expression of GRP78, CHOP, p-IRE1α, TRAF2, and p-NF-κB, suggesting that ER stress is involved in VILI though the IRE1α/TRAF2/NF-κB signaling pathway in mice. 相似文献
108.
《Clinical neurophysiology》2020,131(1):213-224
ObjectiveSystematically review the abnormalities in event related potential (ERP) recorded in Rett Syndrome (RTT) patients and animals in search of translational biomarkers of deficits related to the particular neurophysiological processes of known genetic origin (MECP2 mutations).MethodsPubmed, ISI Web of Knowledge and BIORXIV were searched for the relevant articles according to PRISMA standards.ResultsERP components are generally delayed across all sensory modalities both in RTT patients and its animal model, while findings on ERPs amplitude strongly depend on stimulus properties and presentation rate. Studies on RTT animal models uncovered the abnormalities in the excitatory and inhibitory transmission as critical mechanisms underlying the ERPs changes, but showed that even similar ERP alterations in auditory and visual domains have a diverse neural basis. A range of novel approaches has been developed in animal studies bringing along the meaningful neurophysiological interpretation of ERP measures in RTT patients.ConclusionsWhile there is a clear evidence for sensory ERPs abnormalities in RTT, to further advance the field there is a need in a large-scale ERP studies with the functionally-relevant experimental paradigms.SignificanceThe review provides insights into domain-specific neural basis of the ERP abnormalities and promotes clinical application of the ERP measures as the non-invasive functional biomarkers of RTT pathophysiology. 相似文献
109.
目的对附加钢板技术治疗股骨干髓内钉术后骨不连的历史、现状和进展进行综述。方法广泛查阅国内外关于附加钢板技术治疗股骨干髓内钉术后骨不连的临床研究文献,并进行综合分析。结果自 1997 年附加钢板技术已成功用于治疗股骨干髓内钉术后骨不连,根据原髓内钉是否失效,可分为保留原髓内钉和更换原髓内钉两类。该技术不仅适用于简单骨不连,还可用于合并严重畸形的复杂性骨不连。相比更换髓内钉、更换外侧钢板和双钢板技术,附加钢板技术手术创伤更小,骨折愈合时间更短,骨折愈合率更高,患者能更早重返社会和工作。然而,该技术也存在一些问题有待解决,包括双皮质螺钉固定困难、缺乏适合股骨干解剖型附加钢板以及缺乏术后功能和生活质量的评估研究。结论相比其他翻修固定方式,附加钢板技术能够获得更高的骨折愈合率和更好的临床预后。然而,术后患者能否在功能和生活质量方面进一步获益还有待证实。此外,还需要更高质量的临床对照研究深入证明其是否确实优于其他翻修固定方式。 相似文献
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