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21.
An experimental animal hypoxia model has been developed. It consists of two sensors (an in vitro and in vivo model), an experimental device and a computer signal processing system. This method can easily be applied to determine and analyse blood oxygen saturation at various hypoxia levels. It can also be used to evaluate the accuracy of pulse oximetry over a wide range of oxyhemoglobin desaturation levels. The DC and AC components of recorded red and infra-red signals, the dual-wavelength ratio R12 and the reading of a pulse oximeter (SpO2) can be automatically calculated and displayed on a computer screen. Preliminary results of the animal hypoxia test indicate that the measurements made by the instrument correlate well with the oxygen saturation readings of the automatic blood gas analyser AVL945. The computer analysis system is suitable for repeated estimations in the animal model.  相似文献   
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医疗机构实施ISO9001,其目的是为了提高医疗服务质量,满足病人一切明确和隐含的需求。那么,内审是否发挥作用,直接关系管理体系的有效性。文章对此进行了初步的探讨,即:①明确内审的目的是检查体系满足标准要求的程度;②建立正规的内审机构,要选拔责任心强、综合素质高的人担任内审员;③编制合理且有特色的内审计划,是内审有效性的关键;④适当增加专题审核;⑤医院最高管理者应重视内审结果。  相似文献   
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Interleukin (IL)-17 is a proinflammatory cytokine primarily secreted by Th17 cells, which are a CD4+ T-cell subset. Th17 cells and IL-17 are important in the pathogenesis of multiple sclerosis and in its established animal model, experimental autoimmune encephalomyelitis (EAE). However, it is unclear whether IL-17 contributes to EAE immune tolerance. We used the myelin basic protein (MBP) peptide MBP 68–86 to induce nasal tolerance to EAE, and simultaneously interfered with the tolerance by treatment with different doses of IL-17. We found that IL-17 dramatically interfered with MBP 68–86-induced immune tolerance. IL-17 administration increased IL-6 release, skewing T cell differentiation towards Th17 cells and decreasing the number of Treg cells. This led to an imbalance between Treg cells and Th17 cells and spurred the development of EAE.  相似文献   
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Objective:To investigate whether ketamine could inhibit lipopolysaccharide (LPS)-induced intracellular calcium elevation and NF-kappa B activation in monocytes. Materials and methods:Isolated rat monocytes were challenged with 10 g/ml LPS with or without the presence of various concentrations of ketamine (10, 100, 1000 M). Intracellular calcium was monitored by laser confocal microscopy. NF-kappa B activity of the nuclear extracts of monocytes was analyzed by electrophoretic mobility shift assay (EMSA). Results:LPS provoked a significant calcium elevation and enhanced NF-kappa B activity in monocytes. Ketamine above concentration of 100 M inhibited endotoxin-induced intracellular calcium elevation and NF-kappa B activity. Ketamine itself had no effect on either of them. Conclusions:These findings suggest that ketamine could suppress NF-kappa B in monocytes exposed to endotoxin, and this anti-inflammatory effect might act through attenuating intracellular calcium elevation.Received 31 October 2003; returned for revision 18 December 2003; accepted by I. Ahnfelt-Rønne 26 Januaryy 2004  相似文献   
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BackgroundPyriform sinus fistula (PSF) is a rare congenital anomaly, and the preferred definitive treatment is yet to be verified. In this study, we investigated the treatment outcomes of PSF specifically comparing endoscopic-assisted surgery and endoscopic radiofrequency ablation (RA).MethodsThe medical records of patients treated for PSF at the Shanghai Children's Hospital between October 2016 and September 2019 were retrospectively evaluated.ResultsThere were 93 girls and 98 boys. The median age at onset and operation was 3 years and 5 years, respectively. Endoscopic-assisted surgery was performed in 143 patients. During the same period, RA was performed in 48 patients, and 10 of them concurrently underwent incision and drainage of neck abscesses. Longer hospital stay was found in the endoscopic-assisted surgery group than in the RA group (10.50 ± 3.93 vs. 5.02 ± 3.30 days, P < 0.001). Postoperative complications were not significantly different between the two groups, except for neck infection (0 vs. 8.3%, P = 0.004). After a median follow-up period of 21 months, no significant difference was found between the two groups in terms of recurrence (1.4% vs. 0, P = 0.560).ConclusionPatients treated with RA had a significantly shorter hospital stay than those treated with endoscopic-assisted surgery. Outcomes of endoscopic-assisted surgery and RA were not significantly different for the management of PSF and treatment method should be tailored to the patient.Level of evidenceIV.  相似文献   
28.

Bauxite residues are a mass of industrial wastes derived from aluminum metallurgy. This work provided a simple pyrolysis method to magnetize the bauxite residue to serve as a magnetic adsorbent towards heavy metals removal. The X-ray diffraction patterns and Mossbauer spectrum results confirmed the partial reduction of iron species with an obvious enhancement in magnetization. The magnetized bauxite residue exhibited excellent removal efficiencies for Cu2+, Cd2+ and Pb2+ with maximum adsorption capacities of 219.0 mg g?1, 275.4 mg g?1, and 100.4 mg g?1, which could be quickly separated through a magnet. The adsorption equilibrium data were fitted to the Langmuir isotherm model, while the adsorption kinetics followed a pseudo-first-order model. According to the characterization results, chemical precipitation and sorption was the major mechanism for the removal of Cu2+, Pb2+, and Cd2+. Thus, the magnetized bauxite residue exhibited promising applications for heavy metals removal in wastewater.

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29.
目的 :探讨不育男性精浆转铁蛋白 (Tf)含量与精子顶体完整性的关系。方法 :149例不育男性患者按精子密度≥ 2 0× 10 6 / ml和 <2 0× 10 6 / ml分正常精子密度组和少精子组 ,同时进行精浆 Tf和精子顶体完整率 (PIA)分析。结果 :不育男性少精子组精浆 Tf含量显著低于正常精子密度组 (P<0 .0 1) ;正常精子密度的不育男性精子 PIA<80 %组精浆 Tf含量显著低于精子 PIA≥ 80 %组 (P<0 .0 1)。结论 :正常精子密度的不育男性精子 PIA下降与精浆 Tf水平有密切的关系  相似文献   
30.
目的建立注射用阿莫西林钠克拉维酸钾细菌内毒素检查方法.方法按中国药典2000年版附录细菌内毒素检查法要求进行试验.结果注射用阿莫西林钠克拉维酸的浓度为2.5mg/ml时不干扰鲎试剂与细菌内毒素的凝胶反应.结论细菌内毒素检查法适用于检测注射用阿莫西林钠克拉维酸钾中的内毒素.  相似文献   
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