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131.
文章实验通过高效磨矿分级技术、铅锑浮选新药剂、高效锌硫分离技术、细泥锡石回收新技术的研究,研究出了更适合105号矿体矿石的工艺流程和新技术,解决了过去100号矿选矿存在的磨矿锡石过粉碎、铅锑精矿含锌较高、锌硫分离精矿质量难保证、作业回收率低、矿泥锡石选别指标差等长期存在的技术难题。 相似文献
132.
Walter G. Guder 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2014,24(1):25-30
In the 70ies of the last century, ther term “preanalytical phase” was introduced in the literature. This term describes all actions and aspects of the “brain to brain circle” of the medical laboratory diagnostic procedure happening before the analytical phase. The author describes his personal experiences in the early seventies and the following history of increasing awareness of this phase as the main cause of “laboratory errors”. This includes the definitions of influence and interference factors as well as the first publications in book, internet, CD-Rom and recent App form over the past 40 years. In addition, a short summary of previous developments as prerequesits of laboratory diagnostic actions is described from the middle age matula for urine collection to the blood collection tubes, anticoagulants and centrifuges. The short review gives a personal view on the possible causes of missing awareness of preanalytical causes of error and future aspects of new techniques in regulation of requests to introduction of quality assurance programs for preanalytical factors. 相似文献
133.
Giuseppe Lippi Massimo Daves Camilla Mattiuzzi 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2014,24(1):80-88
The use of contrast media such as organic iodine molecules and gadolinium contrast agents is commonplace in diagnostic imaging. Although there is widespread perception that side effects and drug interactions may be the leading problems caused by these compounds, various degrees of interference with some laboratory tests have been clearly demonstrated. Overall, the described interference for iodinate contrast media include inappropriate gel barrier formation in blood tubes, the appearance of abnormal peaks in capillary zone electrophoresis of serum proteins, and a positive bias in assessment of cardiac troponin I with one immunoassay. The interference for gadolinium contrast agents include negative bias in calcium assessment with ortho-cresolphthalein colorimetric assays and occasional positive bias using some Arsenazo reagents, negative bias in measurement of angiotensin converting enzyme (ACE) and zinc (colorimetric assay), as well as positive bias in creatinine (Jaffe reaction), total iron binding capacity (TIBC, ferrozine method), magnesium (calmagite reagent) and selenium (mass spectrometry) measurement. Interference has also been reported in assessment of serum indices, pulse oximetry and methaemoglobin in samples of patients receiving Patent Blue V. Under several circumstances the interference was absent from manufacturer-supplied information and limited to certain type of reagents and/or analytes, so that local verification may be advisable to establish whether or not the test in use may be biased. Since the elimination half-life of these compounds is typically lower than 2 h, blood collection after this period may be a safer alternative in patients who have received contrast media for diagnostic purposes. 相似文献
134.
?erif Ercan Mustafa ?al??kan Erhan Koptur 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2014,24(3):391-395
Introduction:
There are a number of pre-analytical and analytical factors, which cause false results in the complete blood count. The present case identifies cold agglutinins as the cause for the mismatch between hematocrit and hemoglobin values.Materials and methods:
70-year old female patient had a history of cerebrovascular diseases and rheumatoid arthritis. During routine laboratory examination, the patient had normal leukocyte and platelet counts; however, the hemoglobin (Hb: 105 g/L) and hematocrit (HCT: 0.214 L/L) results were discordant. Hemolysis, lipemia and cold agglutinin were evaluated as possible reasons for the mismatch between hematocrit and hemoglobin values.Results:
First blood sample was slightly hemolysed. Redrawn sample without hemolysis or lipemia was analyzed but the mismatch became even more distinct (Hb: 104 g/L and HCT: 0.08 L/L). In this sample, the titration of the cold agglutinin was determined and found to be positive at 1:64 dilution ratios. After an incubation of the sample at 37°C for 2 hours, reversibility of agglutination was observed.Conclusion:
We conclude that cold agglutinins may interfere with the analysis of erythrocyte and erythrocyte-related parameters (HCT, MCV, MCH and MCHC); however, Hb, leukocyte and platelet counts are not affected. 相似文献135.
卢建玲 《六盘水师范高等专科学校学报》2014,(1):84-88
高中数学有效性教学是高中数学新课程改革的必然要求,具有教学目标明晰、学生全员参与、教学方式灵活、师生良性互动、教学评价多元等特点。本文针对当前高中数学教学出现教学目标片面化、教学内容宽泛化、教学方式单一化、教学活动形式化、教学评价简单化、教学效果低效化等问题,提出新课程视阈下高中数学有效性教学的基本路径。 相似文献
136.
长期以来,高校公共教育学教学一直处于无效或低效状态,原因主要是专业定位出现偏差、教学过程中的教法低效、教材低效、评价低效等问题。要想解决这些问题,改变学生对教育学的错误认识,必须同时改变教学法、使用更好的教材、提高评价的水平和质量。 相似文献
137.
“数学是人类文化的重要组成部分,数学素养是现代社会每一个公民应该具备的基本素养”。课堂教学是传播数学文化的重要途径,本文探讨了数学课堂教学中渗透数学文化的有效途径。 相似文献
138.
小组合作模式促进班级有效管理 总被引:1,自引:0,他引:1
班级常规管理面临的问题复杂,涉及学生的道德教育、文明礼仪、环境卫生、教学常规、集体活动等方面的内容。由于这些班级管理内容繁琐,本人认为在班级常规管理实践中应运用积极心理学的理论作为指导,实施“小组竞争”班级常规管理模式,不仅大大提高学生的学习积极性,还可以培养学生自主学习的积极性和与他人合作的能力,更能提高个人的管理能力,从而达到班级班风和学风提升的有效管理效益。 相似文献
139.
从复杂性理论视角出发,探讨大学专业课程有效教学问题,集中探讨大学专业课程有效教学的理论、特征,大学专业课教师怎样进行有效教学以及如何成为有效教师等问题,以提高大学专业课教师的教学能力和教学有效性,最终促进大学专业课教学质量的提高。 相似文献
140.
优化实验教学内容,改良教学方法,创新教学手段,量化考核办法,提高学生的实验技术水平和分析解决问题的能力,为社会输送高层次技术性、应用型人才打下基础。 相似文献