Lead is a kind of poisonous heavy metal which is widely existed in our environment. It is so harmful for children’s health. The whole society has paid much attention to this problem all the time. Blood lead level is an important index which can measure how seriously children have been exposed to lead. By consulting the papers on the studies of children's blood lead levels,the sources and influencing factors of blood lead levels of children in China were reviewed in the present paper,meanwhile,some suggestions were provided to decrease the lead contact probability and improve children's health.

lschemic postconditioning(IPo)is a way that after long ischemia on liver graft,animals are given one or several brief reperfusion-ischemia before persistent reperfusion to improve the hepatic tolerance and relieve the ischemie reperfusion injury.It has been proved an effective and controlled method to attenuate the ischemic reperfusion injury.Protective mechanism of ischemic postconditioning on hepatic graft is related with protecting sinus hepaticus endotheliocyte and hepatic microcirculation,relieving hepatic cells injury and inflammatory reaction induced by oxygen free radicals,relieving calcium ovedoad in hepatic cells and mitochondria,regulating apoptosis genes,transforming ion channels condition in mitochondria.This article will makes a brief review on protective mechanism ofhepatic ischemic posteanditioning.

OBJECTIVE:To develop a method for concentration determination of voriconazole in human plasma and apply it in the clinic. METHODS:UPLC-MS/MS method was adopted. Using ketoconazole as internal standard,the determination was per-formed on Shim-pack VP-ODS column with mobile phase consisted of water(containing 1‰ formic acid and 2 mmol/L ammonium acetate)-acetonitrile(gradient elution)at flow rate of 0.3 ml/min and column temperature of 40℃.The electrospray ion source,pos-itive ionizing pattern and multiple reaction monitoring were used;the mass transition ion-pairs of voriconazole and internal standard were m/z 351.2→282.2 and m/z 532.1→490.2. RESULTS:The linear range of voriconazole were 1-10 000 ng/ml (r=0.999 5,n=5),and the limit of quantitation was 1 ng/ml;RSDs of inter-day and intra-day were all lower than 10%;method recovery was higher than 90%(RSD<8%),and extraction recovery was higher than 70%(RSD<8%). The plasma concentrations of voriconazole in 10 patients with invasive fungal infection determined by this method were 507.33-7 011.24 ng/ml,and those of 3 patients were outside the recommended treatment concentration range. CONCLUSIONS:The established method is fast,accurate and sensitive,and can be applied for the therapeutic drug monitoring of voriconazole.

Objective To explore the relationship between pathological changes of liver,serum ALT,expression of P-selectin in serum of mice and different dose of venom,the poisoning time induced by Agkistrodon Halys Pallas venom.Methods Using two -factor factorial design,72 male Kunming mice of clean grade were randomly ( random number) divided into 9 groups (n =8).As per the different doses of snake venom injected and different lengths of time after venom injected,the 9 groups were 0-dose (0.0 mg/kg) 3 hours after saline given group,0-dose 8 hours after saline given group,0-dose 24 hours after saline given group,low-dose (0.5 mg/kg) 3 hours after venom given group,low-dose 8 hours after venom given group,low-dose 24 hours after venom given,high-dose ( 1.0 mg/kg) 3 hours after venom given group,high-dose 8 hours after venom given group and high-dose 24 hours after venom given group.The pathological change of liver tissue was determined,and ALT and expression of P-selectin in serum were detected.Results In the venom given groups,the liver histopathologic scores,serum ALT value and expression of Pselectin in serum were significantly higher than those in control group ( P ＜ 0.05 ),and those in high-dose group were higher than those in low-dose group (P ＜ 0.05 ),and those in 8h groups were higher than those in 3h groups (P＜0.05),and those in 24 h groups were higher than those in 8 h groups (P ＜0.05).As the dose of venom increased and the length of time after venom given extended,the liver histopathologic scores,serum ALT and expression of P-selectin in serum were higher.A positive correlation between Pselectin expression and liver histopathologic scores was found after correlation analysis ( r =0.98,P ＜0.05 ).Conclusions Agkistrodon snake venom can cause acute liver injury with elevated ALT and Pselectin in mice.As higher dose of venom given and longer length of time after venom given extended,more serum ALT and P-selectin are produced.Between acute liver injury and high expression of P-selectin exists a correlation,suggesting overexpression of P-selectin is one of the mechanisms of acute liver injury induced by Agkistrodon Halys Pallas venom.

Objective To estimate the impact of cold wave on daily death of cerebra-cardiovascular diseases in Beijing by using case-crossover design. Methods The data of death counts was provided by Beijing Center for Disease Control and Prevention while the meteorological data was provided by Institute of Urban Meteorology,China Meteorological Administration (CMA),Beijing. The impact of six cold waves from Jan 1,1998 to Jun 30,2000 on daily death of cerebra-cardiovascular diseases were analyzed by using 1∶1 one-directional retrospective design and 1∶2 bi-directional symmetry control design. The cases were the people who dead during winter. Controls were the seventh day before or after the date of cases (or the fourteenth day). Results There were six cold waves in the investigation duration. The third cold wave in which minimum temperature declined obviously with decreasing humidity and increasing air pressure had significantly statistical significance in OR and the lag time of this cold wave was 0 day,the OR values were 1.500 (95%CI:1.032-2.181) for cardiovascular disease (CVD),respectively 1.913 (95%CI:1.066-3.432) for acute myocardial infarction,1.679 (95%CI:1.139-2.474) for cerebra-vascular disease(CBD) respectively. The other five cold waves do not have significant impact on cerebra-cardiovascular diseases. Conclusion Most cold waves studied in Beijing do not impact the daily death counts caused by cerebra-cardiovascular diseases. The cold wave with significant increased air pressure may increase the risk of death of cerebra-cardiovascular diseases without any lag time in Beijing.

Objective To investigate and analyze the current situation of reference intervals and decision limits of reticulocyte count in China.Methods The information related to upper/lower limits,decision limits,data resources,method principles, instruments and reagents of reticulocyte count in 2014 was collected via the external quality assessment software system based on website.The participants were divided according to their methods and instruments.The SPSS 1 9.0 was used for conducting the data analysis and statistics of results for each group.Results There were 276 laboratories submitting the val-id results.The major resources for reference intervals came from national guide to clinical laboratory procedures (53.99%), instructions of instrument manufacturers (16.30%),textbook (9.78%),instructions of reagents manufacturers (9.06%) and others.The major resources for decision limits were national guide to clinical laboratory procedures (56.06%),instruc-tions of instrument manufacturers (16.67%),textbook (7.58),instructions of reagents manufacturers (7.58%)and others. The medians and averages of upper/lower limits and decision limits among subgroups were close,whereas the P2.5 and P97.5 were significant discrepancies.Only 45.65% and 48.48% of participant laboratories had verified reference intervals and deci-sion limits before clinic use.The lower limits and decision limits among subgroups had nostatistical difference (P>0.05), where as the upper limits of different instrument groups had significant differences (P<0.001).Conclusion The current situation of reference intervals and decision limits of reticulocyte count is unsatisfactory.It is certain to establish a uniformed reference interval and decision limits for reticulocyte count,which provides a reference for the standardization of reticulocyte count testing.

Objective Discussthe reference intervals and their sources of lymphocyte subsets by flow cytometry tests by all Chinese clinical laboratories at 2014 with a comparison of difference between different test systems.Methods Questionnaires about reference intervals were distributed to 212 clinical laboratories participating in October 2014 national external quality assessment scheme of lymphocyte subsets by flow cytometry tests of National Center for Clinical Laboratory.Relevant information about reference intervals of 5 relative counting items CD3 + (％),CD3 + CD4 + (％),CD3 + CD8 + (％),CD3-CD16 + CD56 + (％) and CD3-CD19 + (％) was collected by a internet-based external quality assessment software systems.Microsoft Excel 2010 and SPSS 19.0 were used to sort out raw data,eliminate unreasonable or incorrect data,and only analyze source distribution,arithmetic average,median,minimum value,maximum value and percentiles (P2.5 and P97.5) of upper and lower limits about healthy adults' reference intervals.Laboratories derived from the highest percentage of source distribution whose reagent and instrument were matching with each other were grouped according to the test systems used and the differences of reference intervals between different systems were compared with Mann-Whitney test.Results For five items collected,in the clinical laboratories who accepted statistical analysis,respectively 39.32％ (81/ 206),37.44％ (79/211),37.68％ (78/207),37.11％ (72/194),36.98％ (71/192) of them had verified the reference intervals they used.The top three sources of reference intervals were instructions of reagent and instrument manufactures (49.70％-52.54％),calculations by laboratories themselves (18.64％-20.00％),and calculations by other laboratories (14.12％-15.43％).The arithmetic averages and medians of upper and lower limits about every item were relatively close.But the minimum and maximum values of upper and lower limits of certain items had moderate differences.As Mann-Whitney test later showed,all items with the P values of upper and lower limits between different test systems,except for the lower limit of CD3 + CD4 + (％) (P value is 0.052) and the upper limit of CD3-CD19 + (％) (P value is 0.117),were lower than 0.05 which meant an existing statistical difference.Conclusions The sources of lymphocyte subsets by flow cytometry tests in all Chinese clinical laboratories were different and the instructions of reagent and instrument had the highest percentage,but the reference intervals among differenttest systems had statistically significance.

The aims of this article is to provide the quality control requirements of preanalytical variation for the determination of trace element aluminum,arsenic,chromium,cadmium and mercury in samples of human origin,reduce the influence of preanalytical variation on the test results.Refer to the Clinical and Laboratory Standards Institute (CLSI) documents,Control of Preanalytical Variation in Trace Element Determinations and other references and guidelines,the methods of quality control of aluminum,arsenic,chromium,cadmium and mercury determination have been made,including:the factors needed to be considered in collection,preservation,transportation and other preanalytical factors,the abilities and considerations of laboratory staff,etc.Hope this article provide some useful suggestions and help to the laboratories of determination of aluminum,arsenic,chromium,cadmium and mercury in samples of human origin.

Objective To describe the reference intervals and their sources of tumor markers in clinical laboratories all over China.And make a comparison of difference between different testing systems.Methods The questionnaires about reference intervals of tumor markers testing were distributed to participants.The information was collected by external quality assessment software system based on website, which including upper and lower limits, sources, validation information and testing systems.The analytes were AFP, CEA, total-PSA, CA125, CA153, CA199, ferritin and free-PSA. The participants were classified according to the testing systems they used.The mean, median, maximum and minimum of each group were calculated using Microsoft Excel 2007.The difference of reference intervals between different testing systems were compared by Kruskal-Wallis test.Results The main source of reference intervals was instructions of testing system manufactures ( 83.1% for mean of 8 ratios ) .The next in sequence were instructions of reagent manufactures(8.4% for mean), National Guide to Clinical Laboratory Procedures (4.6%for mean), determined by their own laboratory(2.0% for mean) and the rest (1.9% for mean). There were 48.0% ( 1 906/3 967 ) of analytes whose reference intervals had been validated.Difference of reference intervals which was with P value of Kruskal-Wallis test with <0.05 was found between different testing system groups except the upper limit of free prostate specific antigen ( PSA ) .Conclusions Most clinical laboratories establish the reference intervals of tumor markers on the basis of instructions of testing system manufactures.The reference intervals among different testing systems have statistically significance.

Objective To carry out the current status of internal quality control by statistical analysis of the Internal Quality Control (IQC)data of homocysteine in 2014 March.Methods Web-based External Quality Assessment (EQA)system was used to collect IQC data of homocysteine from 292 EQA participant laboratories nationwide.The data include thecoefficient of variation (CV)of IQC data under control in March 2014 and long-term cumulative data.Acceptable rates of CVs of two-lot internal quality controls in homocysteine were calculated according to 5 criteria,that were 1/3TEa,1/4TEa and the speci-fications based on biological variation including the minimal,appropriate and optimal allowable imprecision.The instrument the participant laboratories used were sorted into 6 groups and the passing rate of each group were calculated by the 5 crite-ria.Results 292 laboratories reported the data of level 1 IQC for homocysteine,106 of which reported the data of level 2 IQC.The passing rate was different according to different criteria.The passing rate had few difference by the criteria of 1/3TEa and the minimal allowable imprecision based on biological variation,which were from 63.36% to 76.42%.It was also true for 1/4TEa and the appropriate allowable imprecision based on biological variation,which were from 34.25% to 57.55. The passing rate was only 10.62%~16.98% by the criteria of appropriate allowable imprecision based on biological varia-tion.Statistical results showed that instruments the participant mainly used were HITACHI (77/292),Olympus (61/292), Roche (19/292),Beckman (14/292),Abbott (10/292)and Simens (10/292).The passing rates of all the instrument group had few difference except Simens group.Conclusion Most of the laboratories could meet the criteria of 1/3TEa and the min-imal allowable imprecision based on biological variation.But less than half of the laboratories could meet the criteria of 1/4TEa and the appropriate and optimal allowable imprecision based on biological variation.The precision performance of ho-mocysteine among laboratories needs further improvement.