Roles of reference method in clinical biochemistry were introduced.Reference method is an important component of the reference system.Reference methods are primarily used for the establishment and assurance of the traceability of measurement results through calibrating and evaluating routine methods and assigning values to reference materials.Calibration biases and non-specificities of routine methods and the commutability of reference materials are the major issues in the standardization of clinical biochemistry.Standardization also requires availability of commutable reference materials.Reference methods are irreplaceable tools to identify the issues and to characterize reference materials.

Good patient care requires accurate and comparable laboratory test results. To achieve standardization, a reference system consisting of a hierarchal framework of validated and reliable analytical methods linked by reference materials must be in place. Supported by national and municipal research programs, construction of reference systems has been pursued and progress been made. Candidate reference methods have been set up or developed for some important tests, and the methods have been used in the calibration or evaluation of routine methods, study of commutability of control materials and characterization of reference materials. Phenomenal roles of reference systems are expected in diagnostic reagent manufacturing, internal quality assurance and external quality assessments.

specifications are essential for total quality management in laboratory medicine. A consensus among worldwide professionals has been achieved and a hierarchy of strategies for setting analytical quality specifications has been proposed based on their relevance to medical decision-making. Quality specifications derived from biological variations have been widely accepted because of their objectivity and practicability and have more and more been used in the quality management in laboratory medicine.

This article summarized recent correlative literatures focusing on international standards on glycated hemoglobin.The basic concept,determination of glycated hemoglobin,the present review in laboratory measurement and metrological traceability was introduced.The international community has established reference system and metrological traceability to the International System of Units on HbA1c.Determination in glycated hemoglobin is still in incipient stage in our country.Both clinical laboratorians awareness and clinical determination need to be strengthened.

Objective To investigate preanalytical and intraindividual biological variations of 19 biochemistry analytes. Methods For the study of preanalytical variations, 10 consecutive blood specimens were taken from each of 21 individuals and the specimens were taken from different arms and with various evacuated blood tubes and venous occlusion durations and processed with different storages before and after centrifugal separation of serum. Another 3 aliquots of blood, each at an interval of 1 week, were taken from the individuals for the study of intraindividual biological variations. All the serum samples were analyzed in duplicate for 19 biochemistry analytes. Analysis of variance was performed on the results for the estimation of preanalytical and biological variations. Results Various preanalytical treatments or factors caused some systematic variations but random specimen errors were the main contributors of preanalytical variations. Chloride, sodium and calcium showed preanalytical variations of less than 1% and other analytes ranging from 1%-7%. Different analytes showed varied intraindividual biological variations. The least biological variations ( <2% ) were observed on chloride, sodium and calcium and the largest ( >20% ) on bilirubin,triglycerides, alanine aminotransferase and creafine kinase. Conclusions Preanalytical variations under laboratory settings in China and intraindividual biological variations in Chinese for 19 biochemistry analytes have been estimated. These data will be useful in the estimation of measurement uncertainty and the interpretation of clinical laboratory results.

Objective To investigate the effect of standardized usage of antibiotics and hand hygiene on carbapenem-re-sistant Enterobacteriaceae (CRE) infection in neonates. Methods According to the situation of standardized management of an-tibiotics in our hospital, the study period, from January 2011 to December 2013, was divided into pre-intervention, transition and post-intervention. Retrospective study was employed to analyze the antibiotics use density (AUD), the hand hygiene compliance rate among the medical staff, the positive rate of CRE and the nosocomial infection percentage of the neonatology department. Results From pre-intervention to post-intervention period, the AUD was decreased from 12.93 DDDs to 8.10 DDDs;hand hy-giene compliance rate of medical staff was increased from 53.49%to 83.33%;the detection rate of CRE was decreased from 3.71%to 2.27%. The differences were all signiifcant among different periods (P<0.01). The nosocomial infection percentage decreased from 0.22%to 0.17%and there was no signiifcant difference (P=0.441). Conclusions Standardized usage of antibiotics and hand hygiene can be served as economical yet effective approaches to controlling CRE infection in neonates.

AIM: To establish a method for determination of astragloside Ⅳ in Danqi Injection (Radix Salviae Miltiorrhizae,Radix Astragali). METHODS:HPLC-ELSD with Hypersil C_(18) column was used.The mobile phase was composed of acetonitrile-water(38∶62).The flow rate was 0.85 mL?min~(-1).An evaporative light-scattering detector(ELSD) model 2000 was used as detector. RESULTS:For astragloside Ⅳ,the linear range was 1.074-(3.408 ?g),and the average recovery was 100.71%,RSD was 1.79%. CONCLUSION:The method is simple,accurate,reproducible and can be applied to the quality control of the preparation. anqi

A reference system for the completed blood count (CBC) have been established in National Center for Clinical Laboratory (NCCL) according to the standards published by International Council for Standardization in Hematology (ICSH) and International Organization for Standardization (ISO) in order to calibrate hematology analyzer.The contents of our study mainly include:(1)Establishment of calibration laboratory for CBC, which is the first calibration laboratory accepted by China National Accreditation Board for Laboratories in all medical laboratories.(2)We firstly set up the reference method for CBC in China. In addition, the data between NCCL and a foreign reference laboratory have been compared. (3)We have calibrated some instruments from routine laboratories by the fresh blood or calibrator valuated by the reference system, which acts as a new way to calibrate hematology analyzer.(4) A secondary standard assay system has been established and the data between it and the foreign reference laboratory have been compared chronically. The experience has been introduced to local laboratories in 26 provinces.(5) We have drafted out several documents about technical standard for laboratory medicine. The main institution of applications includes: local center for clinical laboratory, clinical laboratories for routine examination, institutions for identification to instruments and reagents, centers for disease control and prevention, and so on.

Objective To assess the diagnostic value of the CT-guided percutaneous lung biopsy in diffuse lung diseases. Methods CT-guided percutaneous lung biopsy was performed using 18G or 20G biopsy needle in 68 patients with diffuse lung diseases. The main imaging changes of these patients included network of diffuse nodular or nodular, diffuse reticular lines shadow and diffuse ground-glass density in the lungs. Results Punctures were successful in all 68 patients, and the diseases were clearly diagnosed, including 19 patients with malignant (9 bronchioloalveolar carcinoma and 10 metastatic carcinoma) and 49 with benign (27 disseminated pulmonary tuberculosis, 8 sarcoidosis, 7 silicosis and coal worker's lung, 2 interstitial pneumonia, 4 pulmonary alveolar proteinosis allergic and 1 pneumonia) lesions. The major complications of puncture were pneumothorax and bleeding, and the incident rate of complications was 17.65%. Conclusion CT-guided percutaneous lung biopsy is a useful, safe technique with low complications, high accuracy rate for the diagnosis of diffuse lung diseases.

Objective To investigate the application and effect of aerobic exercise of pulmonary rehabilitation in patients with chronic obstructive pulmonary disease (COPD).Methods Ninety-four hospitalized patients with COPD from June 2011 to June 2012 were enrolled.The clinical curative effect and safety of aerobic exercise of pulmonary rehabilitation in patients with COPD were observed and compared.Results After 3 months treatment,first second forced expiratory volume (FEV1) and forced vital capacity (FVC) were increased compared with those before treatment [(3.25 ± 0.49) L vs.(2.59 ± 0.55) L,(1.95 ± 0.41) L vs.(1.44 ± 0.48) L],and there were significant differences (P ＜ 0.05).There was no significant difference in FEV1/FVC before and after treatment (P ＞ 0.05).After 3 months treatment,arterial partial pressure of oxygen and arterial oxygen saturation were increased compared with those before treatment [(87.61 ± 8.56) mm Hg(1 mm Hg =0.133 kPa) vs.(63.88 ± 8.79) mm Hg,0.9648 ±0.0449 vs.0.7632 ± 0.0477],partial pressure of arterial carbon dioxide was decreased compared with that before treatment [(30.57 ± 9.47) mm Hg vs.(49.23 ± 9.54) mm Hg],and there were significant differences (P ＜ 0.05).There was no signifi.cant difference in blood pressure and heart rate before and after treatment (P＞ 0.05).No obvious adverse reactions were observed.Conclusions The aerobic exercise of pulmonary rehabilitation can improve significantly lung function.It is safe and rehable,and has less adverse reaction in patients with COPD.It is worthy of promotion and use.