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71.
目的研究降钙素原(PCT)及乳酸水平在早期诊断颅脑术后颅内感染的意义。方法颅脑术后颅内感染患者(n=20)和非颅内感染患者(n=20)的脑脊液和血液样本,检测脑脊液和血清PCT,脑脊液和血液乳酸水平等指标并进行统计分析。结果感染组脑脊液和血清PCT、乳酸水平较非感染组显著升高,差异有统计学意义(P0.05)。脑脊液PCT和乳酸水平诊断敏感性及特异性均较血清PCT和乳酸水平高。结论脑脊液PCT、乳酸在颅脑手术术后颅内感染的诊断中均有意义,其中脑脊液PCT较乳酸敏感性更高,临床应用价值更大。 相似文献
72.
Xue Yao Yan Zhang Jian Hao Hui-Quan Duan Chen-Xi Zhao Chao Sun Bo Li Bao-You Fan Xu Wang Wen-Xiang Li Xuan-Hao Fu Yong Hu Chang Liu Xiao-Hong Kong Shi-Qing Feng 《中国神经再生研究》2019,(3)
Ferroptosis is an iron-dependent novel cell death pathway. Deferoxamine, a ferroptosis inhibitor, has been reported to promote spinal cord injury repair. It has yet to be clarified whether ferroptosis inhibition represents the mechanism of action of Deferoxamine on spinal cord injury recovery. A rat model of Deferoxamine at thoracic 10 segment was established using a modified Allen's method. Ninety 8-week-old female Wistar rats were used. Rats in the Deferoxamine group were intraperitoneally injected with 100 mg/kg Deferoxamine 30 minutes before injury. Simultaneously, the Sham and Deferoxamine groups served as controls. Drug administration was conducted for 7 consecutive days. The results were as follows:(1) Electron microscopy revealed shrunken mitochondria in the spinal cord injury group.(2) The Basso, Beattie and Bresnahan locomotor rating score showed that recovery of the hindlimb was remarkably better in the Deferoxamine group than in the spinal cord injury group.(3) The iron concentration was lower in the Deferoxamine group than in the spinal cord injury group after injury.(4) Western blot assay revealed that, compared with the spinal cord injury group, GPX4, xCT, and glutathione expression was markedly increased in the Deferoxamine group.(5) Real-time polymerase chain reaction revealed that, compared with the Deferoxamine group, mRNA levels of ferroptosis-related genes Acyl-CoA synthetase family member 2(ACSF2) and iron-responsive element-binding protein 2(IREB2) were up-regulated in the Deferoxamine group.(6) Deferoxamine increased survival of neurons and inhibited gliosis. These findings confirm that Deferoxamine can repair spinal cord injury by inhibiting ferroptosis. Targeting ferroptosis is therefore a promising therapeutic approach for spinal cord injury. 相似文献
73.
目的探讨支气管哮喘患儿中性粒细胞胞外诱捕网水平与患者免疫功能及临床预后的关系。方法选取本院2017年9月-2018年9月支气管哮喘患者80例作为观察组,并以同期健康体检的30例儿童作为对照组,采用pico Green dsDNA荧光染色定量检测支气管哮喘患者NETs水平,采用T淋巴细胞亚群评价患者免疫功能,对比不同NETs水平患者免疫功能及临床特点,采用Logistic回归分析探讨小儿支气管哮喘急性发作的风险因素。结果观察组白细胞、中性粒细胞、单核细胞、Cf-DNA/NETs水平均高于对照组(P <0. 05),而淋巴细胞水平低于对照组,差异均有统计学意义(P <0. 05)。Logistic回归分析显示,哮喘家族史、呼吸道感染、Cf-DNA/NETs水平上升、有害气体接触、被动吸烟均是支气管哮喘急性发作的独立危险因素(P <0. 05)。结论中性粒细胞胞外诱捕网水平与支气管哮喘患者免疫功能及预后密切相关,值得临床重点关注。 相似文献
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77.
Sheng Zhang Yan Wang Jie Xu Bokyung Kim Wenbin Deng Fuzheng Guo 《The Journal of neuroscience》2021,41(2):251
The developing CNS is exposed to physiological hypoxia, under which hypoxia-inducible factor α (HIFα) is stabilized and plays a crucial role in regulating neural development. The cellular and molecular mechanisms of HIFα in developmental myelination remain incompletely understood. A previous concept proposes that HIFα regulates CNS developmental myelination by activating the autocrine Wnt/β-catenin signaling in oligodendrocyte progenitor cells (OPCs). Here, by analyzing a battery of genetic mice of both sexes, we presented in vivo evidence supporting an alternative understanding of oligodendroglial HIFα-regulated developmental myelination. At the cellular level, we found that HIFα was required for developmental myelination by transiently controlling upstream OPC differentiation but not downstream oligodendrocyte maturation and that HIFα dysregulation in OPCs but not oligodendrocytes disturbed normal developmental myelination. We demonstrated that HIFα played a minor, if any, role in regulating canonical Wnt signaling in the oligodendroglial lineage or in the CNS. At the molecular level, blocking autocrine Wnt signaling did not affect HIFα-regulated OPC differentiation and myelination. We further identified HIFα–Sox9 regulatory axis as an underlying molecular mechanism in HIFα-regulated OPC differentiation. Our findings support a concept shift in our mechanistic understanding of HIFα-regulated CNS myelination from the previous Wnt-dependent view to a Wnt-independent one and unveil a previously unappreciated HIFα–Sox9 pathway in regulating OPC differentiation.SIGNIFICANCE STATEMENT Promoting disturbed developmental myelination is a promising option in treating diffuse white matter injury, previously called periventricular leukomalacia, a major form of brain injury affecting premature infants. In the developing CNS, hypoxia-inducible factor α (HIFα) is a key regulator that adapts neural cells to physiological and pathologic hypoxic cues. The role and mechanism of HIFα in oligodendroglial myelination, which is severely disturbed in preterm infants affected with diffuse white matter injury, is incompletely understood. Our findings presented here represent a concept shift in our mechanistic understanding of HIFα-regulated developmental myelination and suggest the potential of intervening with an oligodendroglial HIFα-mediated signaling pathway to mitigate disturbed myelination in premature white matter injury. 相似文献
78.
骨质疏松症是老年人,尤其是绝经后妇女最为常见的退行性骨代谢疾病,是导致老年人病理性骨折的重要原因。由于骨质疏松的发生毫无预警容易被忽视,因此成为人类健康的“隐形杀手”。钙、磷、维生素D等营养元素对维护骨骼健康有着重要的意义,但现在大多数营养流行病学研究都只关注单个营养元素对骨骼健康的影响,无法充分解释营养素之间相互作用的复杂关系,而从膳食模式角度来阐明典型的饮食模式和骨骼健康之间存在的关联更具有科学性,本文将从对骨骼健康有益的地中海饮食和具有争议的素食饮食展开讨论和探究。 相似文献
79.
80.
目的分析真菌性血流感染的病原菌分布以及耐药特征,为真菌血流感染的早期合理用药提供理论依据。
方法回顾性分析武汉大学人民医院2016年1月至2018年12月收治的真菌性血流感染者的菌群、科室分布以及耐药性。
结果入组192例真菌血流感染者的血培养样本中共分离192株真菌,其中白色念珠菌检出率为31.77%(61/192),其次热带念珠菌检出率为18.75%(36/192);重症医学科检出率最高为33.85%(65/192)。所有菌株均对两性霉素B敏感,对其他抗菌药物耐药率分别为5-氟胞嘧啶4.49%(9/192)、伊曲康唑5.73%(11/192)、氟康唑10.94%(21/192)和伏立康唑11.46%(22/192);除两性霉素B外,2016至2018年真菌对其他抗菌药物的耐药率均逐年上升,其中2018年所分离192株光滑念珠菌对伊曲康唑耐药菌率达46.7%。
结论真菌血流感染病原菌以念珠菌属为主,对目前抗真菌药物具有较高敏感性,但耐药率逐年上升,加强监测血培养病原菌变化及耐药趋势对指导临床用药至关重要。 相似文献