共查询到19条相似文献，搜索用时 671 毫秒
1.
《赤峰学院学报(自然科学版)》2008,(12)
目的:了解内蒙古赤峰市0～5岁儿童血清维生素A水平现状,为采取相应的干预措施提供参考依据.方法:抽取内蒙古赤峰市市区和农村5岁以下儿童208名,取其末梢血并提取血清,采用微量荧光法测定血清中维生素A含量.结果:城市儿童血清维生素A水平为(32.758±6.215)μg/dl,农村儿童血清维生素A水平为(28.535±6.742)μg/dl,城市儿童血清维生素A水平明显高于农村儿童,差异有统计学意义;市区和农村不同年龄儿童血清维生素A肯定缺乏所占比例不同,差异有统计学意义;农村儿童维生素A肯定缺乏所占比例较高.结论:维生素A缺乏是发展中国家普遍存在的公共卫生问题,特别是儿童,要加强对儿童维生素A缺乏状况及影响因素的了解,以便尽早采取干预措施以预防其发生. 相似文献
2.
本文用日立7150型全自动生化仪及国产脂蛋白试剂盒(免疫透射比浊法)参考有关文献设定参数,测定了40名健康人和132名不同疾病患者的血清APOA—Ⅰ及B。结果正常对照组和部分疾病组间APOA—Ⅰ及B含量有显著差异(P<0.05)。本法操作简便、精密度、准确度良好,线性范围APOA—Ⅰ达3.78 g/L,APOB达2.98 g/L;平均OCV和RCV:APOA—Ⅰ为2.31％、2.62％,APOB为1.92％、2.81％;回收率APOA—Ⅰ为95—101％、APOB为96—104％;与手工法比较,r=0.982,二法相关性良好。胆红素62.1μmol/L以下,血红蛋白18.2 g/L以下对本法无干挠,适于自动分析仪批量样本的检测。 相似文献
3.
目的:评价酶循环法(ECM)定量检测血清同型半胱氨酸(Hcy)的技术性能。方法:参考NCCLS评价方案,评价ECM定量检测血清Hcy的准确度、精密度、线性范围和干扰因素。结果:ECM定量检测低、高水平定值质控血清Hcy的相对偏差分别为2.52%和4.28%;正常值和高值血清测定的批内变异系数(CV)和总CV分别为1.63%~1.58%和4.65%~3.88%;3.12~49.98 umol/L范围内测定的线性相关系数(r2)达到0.9971;胆红素(20 mg/dL)、乳糜(1000 mg/dL)和维生素C(10 mg/dL)对该检测方法无显著性干扰(P>0.05)。结论:酶循环法不仅实用性高,而且可靠性强,因此在各级医疗机构的检验科均可普及使用。 相似文献
4.
利用维生素C对高锰酸钾的褪色效应建立了褪色光度法测定维生素C的新方法。在1 moL／L H2 SO4介质中,维生素C使高锰酸钾褪色。在波长525 nm处,测定高锰酸钾溶液褪色前后吸光度,吸光度的变化值△A与维生素C的浓度在0～20μg／mL范围内成线性关系,R2＝0.9998。用于样品中维生素C的含量测定,回收率在101％～105％之间,RSD为1.1％。 相似文献
5.
分光光度法测定药片中维生素C的含量 总被引：2，自引：0，他引：2
在1mol／L H2SO4介质中，维生素C使高锰酸钾褪色。在525nm处测高锰酸钾的吸光度的变化值△A。△A与维生素C的浓度在0～240μg／mL范围内成线性关系，R=0．9993。用于样品中维生素C的含量测定，回收率在97％～110％之间。 相似文献
6.
一、选择题饮用天然水理化指标测定结果1.日常生活中,我们经常饮用钙≥4.0mg/L镁≥0.5mg/L矿泉水。右图是某饮用天然水部分钾≥0.35mg/L钠≥0.8mg/L商标图,图中列出了理化指标。这偏硅酸≥1.8mg/L里的钙、镁、钾、钠指的是pH值(25℃)7.1A.单质B.原子C.分子D.元素2.下列粒子结构示意图中表示阳离子的是A.+1028B.+828C.+1228D.+9283.2003年10月15日,我国用“长征”二号F捆绑式火箭将“神舟五号”载人飞船成功送上太空。火箭用联氨(N2H4)作燃料,一氧化氮作氧化剂。反应的化学方程式是:N2H4+2NO点燃2X+2H2O则X的化学式A.N2B.NO2C.N… 相似文献
7.
我园在省儿童保健院的协助下,对新入园的220名幼儿进行了血清维生素 A 水平测定。检查结果显示,维生素 A 缺乏(即测定值20μg/dl)者5人,占2.27%,亚临床维生素 A 缺乏(即20～39.8μg/dl)者59人,占39.8%。由此可见,维生素 A不足的幼儿占有相当大的比例。维生素 A 对人体很多系统具有重要作用,它不仅能促进体内组织蛋白的合成,加速生长发育,且能提 相似文献
8.
采用紫外分光光度法测定了赣南脐橙中的维生素C含量,探讨了波长、静置时间等相干实验条件.结果表明,最大吸收波长243 nm,宜静置时间40 min,最佳pH=10,得到的回归方程ΔA=0.05496C+0.00651,相关系数r=0.9999,维生素C浓度在1.00—12.0μg/mL范围内与紫外吸收值呈良好的线性关系,利用此方法测定样品中维生素C含量最低检出限0.014μg/mL,回收率98.4%—101.0%之间,相对标准偏差RSD<5%. 相似文献
9.
1选用常用化学药品全日制义务教育《生物课程标准》(实验稿)为教师提供了模拟“血型签定”的案例,实验材料器具为:模拟配制的A型血(0.02mol/L的Pb(NO3)2,硝酸铅),B型血(0.02mol/L的BaCl2,氯化钡),O型血(蒸馏水),AB型血(上述A型血和B型血等量混合)和A型血清(0.02mol/L的AgNO3,硝酸银),B型血清(0.02mol/L的碘化钠);载玻片,吸管等。根据同型血不产生凝集反应,异型血产生凝集反应的原理,笔者重新设计选用了以下药品:硫酸镁Mg-SO4溶液代表A型血和A型血清,氯化钡BaCL2溶液代表B型血和B型血清,碳酸钠Na2CO3和氢氧化钠NaOH的混和溶液… 相似文献
10.
目的:探讨肝硬化患者血清中抗心磷脂抗体(ACA)的含量变化及其与肝硬化病情的演变关系.探索抗心磷脂抗体(ACA)与Child-Pugh分级和普通肝功能及肝纤维化指标间的联系与影响.方法:应用酶联免疫吸附法(ELISA)分别对不同分级的肝硬化患者血清中抗心磷脂抗体(ACA)的含量进行了测定;用酶法测定了ALT、AST与胆汁酸并计算AST/ALT值;用Peariman和Lee改良法测定血清胆红素;用溴甲酚氯比色法测定血清白蛋白;用放射免疫分析法测定透明质酸(HA)、Ⅲ型前胶原氮端肽(PⅢNP)、层粘连蛋白(LN)与Ⅳ型胶原(Ⅳ.C);并测定了凝血酶原时间(PT)与血小板计数等相关指标.结果:肝硬化患者血清抗心磷脂抗体(ACA)的阳性率Child-Pugh A、B、C三级逐级升高,随肝硬化病情加重而增加;血清胆红素和凝血酶原时间(PT)与ACA呈显著正相关(P＜0.01),血清白蛋白与血小板计数与ACA呈显著负相关(P＜0.01);ALT、AST、AST/ALT、胆汁酸与ACA相关无显著性(P＞0.05);ALT、AST、AST/ALT对ACA的影响有显著性(P＜0.01),以AST/ALT为最强;透明质酸(HA)、Ⅲ型前胶原氮端肽(PⅢNP)、层粘连蛋白(LN)及Ⅳ型胶原(Ⅳ.C)与ACA均呈显著正相关(P＜0.01,P＜0.05);HA、PⅢNP、LN、Ⅳ.C四者中,只有HA与PⅢNP对ACA的影响有显著性(P＜0.01),以HA为最强.结论:肝硬化患者血清抗心磷脂抗体(ACA)的阳性率随病情的严重而升高;抗心磷脂抗体(ACA)与Child-Pugh分级和普通肝功能及肝纤维化三者间存在着一定的联系与影响;抗心磷脂抗体(ACA)在肝硬化患者中可能有一定的临床意义. 相似文献
11.
目的：消除血红蛋白和胆红素两种因素对碱性苦味酸速率法测定肌酐的负干扰。方法：用苦味酸速率法测定未溶血、人为溶血、人为溶血后加0．88mol／L H2O2 37℃水浴20min、人为溶血后加0．88mol／L H2O2 37℃水浴30min、未溶血加0．88mol／L H2O2 37℃水浴20min五种处理的血液样品中肌酐值。结果：其他四组与第一组差异均有统计学意义（P〈0．01）;第三组与第二组、第五组测定结果有差别（P〈0．01或P〈0．05）,而第三组与第四组的测定结果则无差别（P〉0．05）。结论：用0．88mol／L H2O2处理溶血样品后,再进行肌酐测定。可消除血红蛋白和胆红素对肌酐测定的影响,使测定结果更真实。 相似文献
12.
信用证支付方式下的收汇风险主要由伪造信用证和"软条款"信用证引起,出口商防范外汇风险的措施包括:慎重选择贸易伙伴;提高业务人员素质;严格审证,认真备单,等等。 相似文献
13.
Xin-bo Wu Guo-xin Fan Xin Gu Tu-gang Shen Xiao-fei Guan An-nan Hu Hai-long Zhang Shi-sheng He 《Journal of Zhejiang University. Science. B》2016,17(7):553-560
Objectives
This study aimed to compare the learning curves of percutaneous endoscopic lumbar discectomy (PELD) in a transforaminal approach at the L4/5 and L5/S1 levels.Methods
We retrospectively reviewed the first 60 cases at the L4/5 level (Group I) and the first 60 cases at the L5/S1 level (Group II) of PELD performed by one spine surgeon. The patients were divided into subgroups A, B, and C (Group I: A cases 1–20, B cases 21–40, C cases 41–60; Group II: A cases 1–20, B cases 21–40, C cases 41–60). Operation time was thoroughly analyzed.Results
Compared with the L4/5 level, the learning curve of transforaminal PELD at the L5/S1 level was flatter. The mean operation times of Groups IA, IB, and IC were (88.75±17.02), (67.75±6.16), and (64.85±7.82) min, respectively. There was a significant difference between Groups A and B (P<0.05), but no significant difference between Groups B and C (P=0.20). The mean operation times of Groups IIA, IIB, and IIC were (117.25±13.62), (109.50±11.20), and (92.15±11.94) min, respectively. There was no significant difference between Groups A and B (P=0.06), but there was a significant difference between Groups B and C (P<0.05). There were 6 cases of postoperative dysesthesia (POD) in Group I and 2 cases in Group IIA (P=0.27). There were 2 cases of residual disc in Group I, and 4 cases in Group II (P=0.67). There were 3 cases of recurrence in Group I, and 2 cases in Group II (P>0.05).Conclusions
Compared with the L5/S1 level, the learning curve of PELD in a transforaminal approach at the L4/5 level was steeper, suggesting that the L4/5 level might be easier to master after short-term professional training.14.
A method was proposed to determine boron trifluoride in boron trifluoride complex using fluoride ion selective electrode(ISE). Hydroxide was chosen to mask aluminum for the determination of 0.01—0.1 mol/L of fluoride. The simulation indicated that the permissible aluminum masked at a certain p H value was limited and hardly related to F-concentration and boric acid. It is better to control p H value below 11.5 and the aluminum concentration within 0.025 mol/L to minimize the interference of hydroxide to the fluoride ISE. The decomposition conditions of boron trifluoride by aluminum chloride were investigated. It is found that the F-detection ratio will approach 1.0 if the Al/F molar ratio is 0.3—0.7 and aluminum concentration is no more than 0.02 mol/L when heated at 80 ℃ for 10 min. In one word, hydroxide is quite fit to mask aluminum for samples which contain high content of fluoride and aluminum and the BF3 content can be successfully determined by this method. 相似文献
15.
Mi Song Kim Wei Loong David Hung Azilawati Bte Jamaludin Seo Hong Lim 《Interactive Learning Environments》2013,21(6):704-720
Learning happens not only in schools, but also in every context that affords new experiences and opportunities for metacognition. We aim to maximize the different activity-milieux in which learners are engaged in developing their life-long learning dispositions to learn within and across contexts. This paper is a follow up of an earlier published paper in which a framework on interpreting learning as how the self interacts with phenomena and reifications was proposed. Grounded in this learning framework, our research seeks to expand the “within context” learning to “across contexts” learning with evidence from a case study examining a 10-year-old boy's learning process. Through the case study, we will describe the interplay between bowling and schooling and how strategies learned from one context is situated into another drawing upon Ito et al.'s (2010) developmental trajectory of “hanging out-messing around-geeking out” perspectives. The findings show that for learning to be meaningful and authentic for the twenty-first century, it is essential for the learner(s) to be in constant dialectical interactions and relationship with oneself, others, and with the social-cultural artifacts that afford the learning. We conclude with practical implications derived from the study. 相似文献
16.
As the City of Houston's Bureau of Air Quality Control embraced new policies, technologies, and rhetorical strategies, they simultaneously moved through Lukensmeyer and Torres's “four levels of public involvement,” which include the information, consultation, engagement, and collaboration levels (Lukensmeyer & Torres, 2006). Because of the technical and scientific nature of air quality inspections, increasing public involvement, especially the involvement of those in a predominantly African American and a predominantly Hispanic neighborhood, has been a challenge. This article describes the Bureau's journey through the information level, where the Bureau opens public access and participation in the investigation and reporting process; the consultation level, where Bureau staff go door-to-door in poor and minority neighborhoods collecting citizen feedback regarding perceived environmental hazards; the engagement level, where the Bureau conducts monthly environmental meetings with neighborhood residents; and the collaboration level, where citizens are taught to collect evidence of environmental violations. 相似文献
17.
Brooke E. E. Montgomery Amy Jones Sharon E. Sanders Angela McGraw Barbara Williams Katherine E. Stewart 《American journal of sexuality education》2018,13(1):40-64
Experiences of violence and behaviors that increase the risk of acquiring a sexually transmitted infection are high among women in the United States, and they often intersect (Meyer, Springer, &; Altice, 2011; Montgomery et al., 2015; World Health Organization (WHO), 2010). However, there are few evidence-based HIV-prevention interventions that address the special needs and challenges faced by female survivors of violence (Centers for Disease Control and Prevention, (CDC), 2017a). To address this gap, we adapted and pilot-tested an existing evidence-based women-focused sexual risk-reduction intervention (The Future Is Ours) with 23 self-identified female survivors of violence. The intervention comprised eight-weekly, two-hour cognitive behavioral group sessions focusing on reducing sexual-risk and improving trauma-based coping skills. Using mixed-methods analyses, the adapted intervention was determined feasible and acceptable to participants, and preliminary results suggest that participation could reduce risk factors for sexually transmitted infections. Therefore, testing on a larger scale is warranted. 相似文献
18.
(R)-2-hydroxy-3-phenylpropionic acid (PLA) is an ideal antimicrobial compound with broad-spectrum activity against a wide range of Gram-positive bacteria, some Gram-negative bacteria, and fungi. We studied the bioconversion of phenylpyruvate (PPA) to PLA using whole recombinant Escherichia coli cells in a series of buffer/organic solvent systems. Octane was found to be the best organic solvent. The optimum volume ratio of the water phase to the n-octane phase, conversion temperature, substrate concentration, and cell concentration were 6:4, 40 °C, 12.5 g/L, and 30 g/L wet cells, respectively. Under the optimized conditions, the average PLA productivity in the aqueous/n-octane system was 30.69% higher than that in the aqueous system, and 32.31 g/L PLA was obtained with the use of a stirred reactor (2-L scale). Taken together, our findings indicated that PLA biosynthesis was more efficient in an aqueous/n-octane biphasic system than in a monophasic aqueous system. The proposed biphasic system is an effective strategy for enhancing PLA yield and the biosynthesis of its analogues. 相似文献
19.
曾炜 《江苏经贸职业技术学院学报》2010,(4)
信用证的软条款从"单"和"证"两个方面给受益人(出口商)的安全收汇设置障碍,使其无法顺利获得货款。信用证本身机制上的缺陷、出口商的管理不善以及进口商出于自身利益目的,使得信用证软条款在外贸实践中大行其道。对此,应采取针对性的防范措施,谨慎处理好信用证使用过程中的各个环节,以防止和避免软条款给出口商带来损失。 相似文献