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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   
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Background and objectivesThe ideal timing of tranexamic acid administration in total knee arthroplasty with tourniquet remains unclear. Our primary objective was to prove if administering it before surgical incision, instead of before releasing the tourniquet, reduces postoperative bleeding. A second objective was to determine whether a second dose reduces post-operative bleeding.Material and methodsA prospective, double-blind clinical trial was performed on 212 patients scheduled for total knee arthroplasty. They were randomised into 4 groups. Tranexamic acid was administered before the surgical incision in “pre-induction groups” (1 and 2), and just before the tourniquet release in “pre-release groups” (3 and 4). Groups 2 and 4 received a second dose 3 hours post-surgery. Main outcome was postoperative bleeding (visible blood loss and calculated total bleeding). Secondary outcomes were haemoglobin variations, complications and transfusion rate.ResultsThe mean calculated total bleeding was 1563 ml (95%CI: 1445 to 1681) in preinduction groups versus 1576 ml (95%CI: 1439 to 1713) in pre-release groups (P = .9); 1579 ml (95%CI: 1452 to 1706) in single-dose groups versus 1559 ml (95%CI: 1431 to 1686) in double-dose groups (P = .82). One patient was transfused. The mean haemoglobin at discharge was 10.4 g/dl (95%CI: 10.2 to 10.7) in singledose groups versus 10.8 (95%CI: 10.6 to 11.1) in double-dose groups (P = .06).ConclusionsThere were no differences in bleeding or transfusion regarding the time of tranexamic acid administration. The second dose had not impact on outcomes.Trial registration: EudraCT 2016-000071-24.  相似文献   
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目的:建立HPLC/TQ-MS测定益母草中阿魏酸含量的方法并测定不同产地益母草中阿魏酸含量,评价益母草中阿魏酸对中成药调经止痛片及新生化颗粒的质量影响,为制定含有益母草并以阿魏酸为定量指标的中成药质量标准提供参考。方法:采用薄层色谱法及UPLC-Q/TOF定性鉴别及分析益母草中阿魏酸,采用HPLC/TQ-MS定量分析10批不同产地益母草中阿魏酸含量。基于定量分析结果及处方用量探讨益母草中阿魏酸含量对其中成药质量标准的影响。结果:薄层鉴别及UPLC-Q/TOF定性分析结果显示,10批不同产地益母草中均含有阿魏酸。HPLC/TQ-MS定量分析结果显示,益母草中阿魏酸含量在0.004 2%~0.006 5%之间。结论:益母草与当归、川芎等含有阿魏酸的药材配伍且其用量较大时,益母草中阿魏酸含量会对其质量评价产生一定的影响。  相似文献   
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In a biological microenvironment, free fatty acids (FFA) as ubiquitous biological molecules might interact with nanoparticles (NPs) and consequently change the toxicological responses. However, whether the chemical structures of FFA could influence their interactions with NPs remain unknown. This study investigated the interactions between ZnO NPs and saturated or unsaturated FFA (complexed to BSA), namely stearic acid (SA, C18:0), oleic acid (OA, C18:1), and α-linolenic acid (ALA, C18:3). It was shown that BSA, SA, OA, and ALA increased the atomic force microscope (AFM) heights as well the polydispersity index (PDI) of ZnO NPs. BSA modestly protected THP-1 macrophages from ZnO NP exposure, whereas OA and ALA led to relatively less cyto-protective effects of BSA. Moreover, only co-exposure to ZnO NPs and SA significantly promoted the release of interleukin-8. BSA, SA, OA, and ALA equally changed intracellular ROS and Zn ions associated with ZnO exposure, but co-exposure to ZnO NPs and OA/ALA particularly activated the expression of endoplasmic reticulum stress-apoptosis genes. In combination, these results showed that FFA could influence the colloidal aspects and toxicological signaling pathway of ZnO NPs, which is dependent on the number of unsaturated bonds of FFA.  相似文献   
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工作相关肌肉骨骼疾患(WMSDs)是常见的慢性非传染性疾病。WMSDs已成为影响工人健康、降低工人生命质量和造成经济损失的重要因素,可见于多个行业、工种。本文对WMSDs流行现状及人体工效学负荷相关研究进行综述,以期找到职业人群保护的可行方法。  相似文献   
70.
1. The present study is designed to investigate the brain distribution and plasma pharmacokinetics profiles of chlorogenic acid (CGA) after intranasal administration in Charles–Foster rats to evaluate whether the CGA molecules are transported directly via the nose-to-brain path.

2. The CGA is administered intravenously (IV) and intranasally (IN) at the dose of 10?mg/kg. Further, its concentration in the plasma, cerebrospinal fluid (CSF) and the whole brain is analyzed by HPLC-UV method.

3. The study observes that CGA is rapidly absorbed in plasma with tmax of 1?min similar to IV route after IN administration. The peak plasma concentration and AUC0–24 are higher by 3.5 and 4.0 times respectively in IV administration, compared to IN delivery that represents the significant less systemic exposure of CGA in IN route.

4. However, the concentration of CGA in the brain is 4, 6.5, 5.3, 5.2 and 4.5 times higher at 30, 60, 120, 240 and 360?min, respectively in IN administration compared to IV administration. The exposure of CGA in the brain after IN administration (AUCbrain, IN) was significantly greater (4 times) as compared to the exposure of CGA in the brain (AUCbrain, IV) after IV administration reflecting significant brain uptake of CGA through nasal route. Therefore, IN delivery of CGA can be a promising approach for the treatment of stroke and neurodegenerative disorders.  相似文献   

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