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51.
本文报导混合浓缩人血清工作标准(89-1)的制备和用WHO相应参考标准血清标定出其中五类免疫球蛋白(Igs)及IgG4亚类含量。该制剂主要用于体外测定IgG、IgA、IgM的工作标准,也可供作体外测定IgD、IgE、IgG4的工作标准。混合前每份血清均无乙型肝炎表面抗原、转氨酶正常。定量分装为每安瓿0.5ml,经冷冻干燥后,4℃保存。参照国际参考标准血清67/97及67/37,分别以免疫单扩散法标定89-1中IgG、IgA、ISM含量;以酶联免疫吸附试验(ELISA)标定IgD、IgG4和IgE含量。其中IgG、IgG4、IgA、IgM含量,应用本室制备的相应单克隆抗体(McAb)标定,而IgD和IgE应用多克隆抗体(PcAb)进行标定。并用五剂量法及四剂量法分别计算Igs含量。 相似文献
52.
Experiments on conscious rabbits were performed using the oddball paradigm, in which a rare (deviant) and common (standard) stimuli were of the same color but different intensities. Deviant stimuli were of lesser intensity. Recordings were made of evoked potentials induced by series of uniform deviant stimuli (without using standard stimuli), which were presented at the beginning and end of stimulation. Visual evoked potentials recorded in response to deviant stimuli in the visual cortex and hippocampus showed increases in the amplitudes of phases, shifted towards positivity as compared with responses to standard stimuli and uniform deviant stimuli at the beginning and end of stimulus blocks. Significant changes affected phases P1 and P2 of visual evoked potentials in the cortex and phases P1, N1, and P2 in the hippocampus. The most significant increase in evoked potentials in the cortex was seen for the P2 peak (P130). It is suggested that changes in responses to oddball-deviant stimuli result from an orienting reflex to rare, unexpected stimuli and that the P2 (P130) peak in the cortex is associated with transmission of information regarding changes in the intensity of the light. The amplitude of this peak was shown to be decreased in responses to uniform deviant stimuli at the beginning and end of stimulus blocks. It was also demonstrated that the clearest and most contrasting changes in visual evoked potentials in responses to deviant and standard stimuli were seen with the smallest differences in intensity between these types of stimulus, this reflecting increases in the orienting reflex at threshold differences. 相似文献
53.
Time course of the increase in airway responsiveness associated with late asthmatic reactions to toluene diisocyanate in sensitized subjects 总被引:4,自引:0,他引:4
C E Mapp R Polato P Maestrelli D J Hendrick L M Fabbri 《The Journal of allergy and clinical immunology》1985,75(5):568-572
To understand better the mechanism of the increase in airway responsiveness associated with late asthmatic reactions, we determined the time course of toluene diisocyanate (TDI) effect on airway responsiveness in six sensitized subjects who exhibited a late asthmatic response after TDI exposure (0.018 +/- 0.005 ppm, 30 min) in the laboratory. Airway responsiveness was assessed before TDI exposure and then at 8 hr, 1 day, 1 wk, and 1 mo after TDI exposure. To assess responsiveness we determined the provocative dose of methacholine causing a decrease in FEV1 of 20% (PD20FEV1). The methacholine PD20 decreased from 0.50 mg geometric standard error of the mean (GSEM = 1.54) to 0.06 mg (GSEM = 1.55) (p less than 0.001) at 8 hr after exposure to TDI, was still decreased to 0.15 mg (GSEM = 1.93) (p less than 0.05) at 1 day, returned to 0.26 mg (GSEM = 1.91) (p greater than 0.05) at 1 wk, and returned to 0.43 mg (GSEM = 1.71) at 1 mo, indicating that full recovery occurred within 1 to 4 wk. These results demonstrate that TDI-induced late asthmatic response is associated with a reversible increase in airway responsiveness to methacholine and suggest that the TDI effect is linked to an acute inflammatory response in the airways. 相似文献
54.
Dr. Eric Delcourt Philippe Franken Andre Lenaers 《European journal of nuclear medicine and molecular imaging》1985,11(4):123-126
When performing equilibrium radionuclide angiocardiography with two successive acquisition views, absolute left-ventricular volumes can be calculated using an internal standard generated by a computer in the left-ventricular cavity. The method is based on the computed ratio of maximum to global activity in the 40°-left-anterior-oblique view after background correction and on the measured depth of the left ventricle in almost-orthogonal, 30°-left-posterior-oblique Fourier first-harmonic images. The method does not require blood sampling or correction for self attenuation. The intra- and interobserver reproducibility is excellent, even in patients with severe impairment of the ventricular-contractility pattern. When compared with a classical method requiring venous-blood counting and an attenuation correction factor, the accuracy of the internalstandard method was fairly good, with a regression coefficient of 0.90. 相似文献
55.
作者自行设计的CSS-Ⅱ型心电图微型计算机自动诊断系统试用于临床,受试者1160例,其中波形异常和心律失常共247份心电图,从913份正常心电图中随机抽样106份,两者共计353份图纸,用本研究诊断确定的“金标准”(Gold standard)与该系统的自动诊断结论进行比较。结果:波形诊断及心律失常的诊断一致率均在90%以上,排除了机遇诊断一致率,其波形为90%,心律失常为88%。 相似文献
56.
Optimum support properties for protein separations by high-performance size exclusion chromatography
Optimum chromatographic properties of high performance size exclusion chromatography (HPSEC) of proteins, such as resolution, molecular weight accuracy and recovery, are obtained on packings and columns with tailor-made physical and chemical structures, employed at properly adjusted eluent compositions and operation conditions. SEC-theory suggests that a broad molecular weight fractionation range and high linearity of the log-linear calibration plot can be achieved by the use of two packings (10- and 80-nm pore size, characterized by a pore-size distribution (psd) equal to or less than 1 decade and by equal internal column porosity (p)), rather than a single 30- to 50-nm pore-size packing with a wide psd. Favourably high-phase ratios of (p)/(o)/ 1.0 for HPSEC columns were accomplished with a minimum interstitial column porosity (o) and a high value for the internal column porosity (p) (the specific pore volume, nu(p), multiplied by the packing density, varrho(p).) Ligands such as diol, N-acetoxyamino and oligomeric ether with a propyl- or propoxy-spacer bonded to the silica at the highest density appear to provide high mass recovery and bioactivity as well as chemical stability. Such packings, available in 3-5 mum particle size ranges of narrow distribution, packed into columns 6 mm i.d. and 500 mm in length, offer the best compromise with respect to resolution, speed and pressure drop. More careful studies are required to explain the effects of protein conformational changes and interconversions during elution on HPSEC columns. 相似文献
57.
目的 探讨单病种护理质量控制在小儿特发性血小板减少性紫癜中的应用效果。方法 将我院2020年1月—2021年6月收治的60例特发性血小板减少性紫癜患儿按照随机数字表法进行编号和分组,其中单号患儿纳入为对照组(30例),接受传统护理模式;双号为观察组(30例),按照小儿特发性血小板减少性紫癜护理质量控制标准分阶段实施评估,制定护理计划,落实护理措施。比较两组患儿:⑴临床治疗相关指标(治疗有效率、平均住院时间及住院费用);⑵护理水平相关指标(护理质量、护理人员业务能力);⑶护理效果相关指标(护理依从性、健康教育知晓率及护理满意度)。结果 ⑴观察组治疗总有效率为80.00%(24/30)高于对照组53.33%(16/30)(χ2=4.800,P=0.028);观察组住院时间及住院费用少于对照组(P<0.001);⑵观察组护理质量及护理人员业务能力高于对照组(P<0.001);⑶护理后,观察组护理依从性、健康教育知晓率及护理满意度高于对照组(P<0.006~0.010)。结论 实施单病种护理质量控制标准管理,有利于提高患儿临床治疗效果及护理效果,提升护理水平,缩短住院时间及费用。 相似文献
58.
针对团标《日间手术中心设施建设标准》结合日间手术中心的特点,阐述了日间手术环境控制暖通空调方面的编写思路、条文要求与实施措施。 相似文献
59.
随着我国医疗器械技术的发展,上下肢康复机器人作为一种新型的医疗器械出现在大众面前,很大程度上替代了传统的康复训练,提高了康复训练的效率。但是上下肢康复机器人的出现也伴随着一些问题,文章结合上下肢康复机器人的一些标准及广东省医疗器械质量监督检验所近年来对上下肢康复机器人的检测情况进行探讨,并提出一些问题和建议,以期能够规范上下肢康复机器人的市场和提高上下肢康复机器人的产品质量。 相似文献
60.
【目的】 勘察国际OA期刊的OA实践及其期刊政策声明,为我国OA期刊建设提供借鉴。【方法】 以DOAJ图情类期刊为研究对象,调查并分析期刊的出版形式如发行媒介、出版周期、收费情况等,以及存档政策、许可条款、OA模式等版权管理政策。【结果】 揭示OA期刊在出版频率、APC、OA模式方面出现的新形式、新模式,分析OA期刊在可访问性、透明性和开放性方面存在的问题。【结论】 OA已经成为学术期刊发展的必然方向,在版权管理方面仍处在初级阶段,认证环节较为混乱,现阶段处于多模式探索尝试阶段;OA期刊的出版管理应在保持适度灵活性的同时,着力加强规范建设。 相似文献