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 discuss the application of allowable total error (Tea) and allowable imprecision derived from biological variation in routine chemistry external quality assessment ( EQA) and internal quality control (IQC) and set up quality specifications of routine chemistry in our country.Methods Data of test items including K,Na,CI,Ca,P,Glu,Urea,UA,Cre,Alb,TP,TC,TG,AST,ALT,Tbil,ALP,AMY,CK,LDH,Fe,Mg,Cu,Zn and GGT was collected and evaluated by a nationwide EQA.At the same time the coefficients of variation (CVs) of these test items during the month were acquired from the IQC reports of each laboratory and then the results were analyzed.Results Percent of pass was different in these test items based on Tea derived from biological variation in EQA results.Except for items of CI,Mg,Cu and Zn,about 80％ of participant laboratories could achieve the minimum performance of biological variation.About 80％ of participant laboratories could achieve the desired performance of biological variation for K,P,Glu,Urea,UA,Cre,TC,TG,ALT,AST,Tbil,AMY,CK,LDH,Fe and GGT.About 80％ of participant laboratories could achieve the optimum performance of biological variation for Urea,UA,TC,TG,ALT,AST,Tbil,C K,and GGT.And the IQC results showed that acceptable percents of different items based on three allowable imprecision were different.More than 80％ of participant laboratories could achieve the minimum allowable imprecision for K,P,Glu,Urea,UA,TC,TG,ALT,AST,Tbil,AMY,CK,LDH,Dbil,Fe,GGT,the desirable imprecision for P,Urea,UA,TG,ALT,AST,Tbil,CK,Dbil,Fe,GGT and the optimum imprecision for TG,ALT,CK,Dbil,Fe.Conclusions The quality specifications derived from biological variation can be as evaluation criteria for EQA and IQC in order to know the detection ability of each laboratory more completely and objectively,set up quality specifications derived from allowable total error and allowable imprecision in routine chemistry and to provide basis for mutual recognition of routine chemistry test results.

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 investigate the longitudinal systolic ventricular function of children with single ventricle, and to appraise the feasibility and clinical value of velocity vector imaging (VVI) on assessing it. Methods The study group consisted of 30 patients with functional single ventricle. The control group consisted of 30 age- and gender-matched normal children. Using Sequoia C512 echocardiography machine,the peak velocity(V),peak displacement(D) ,strain(S) ,and strain rate(SR) were measured. Results Basel and median velocities,as well as basel and median displacements of rudimentary chamber side(RCS), were lower than those of septum[Basel velocity (1. 93 ± 0. 71)cm/s vs (3. 53 ± 1. 07)cm/s;Median velocity (1.19±0. 57)cm/s vs (2. 03 ± 0. 90) cm/s; Basel displacement (2. 53 ± 1.65) mm vs (6.21 ± 2. 12)mm;Median displacement(1. 26 ± 1. 06)mm vs (3. 21 ± 1.37)mm]. The values of strain of all the six segments of single ventricle were significantly lower than Corresponding segments of the control group [ basel nonrudimentary chamber side(NRCS) ( - 16. 17 ± 4. 37) % vs ( - 19. 66 ± 3. 47) % ; Median NRCS ( - 15. 23 +4.36)% vs (-19.64± 4. 75)%; Apical NRCS (-13.84 ± 5.79)% vs ( - 16. 7 ± 4. 15)%; Basel RCS(-10. 54±5.35)% vs (-19.49±3. 74)%;Median RCS ( - 10. 16 ± 5. 26)% vs ( -20. 83 ± 3. 82)% ;Apical RCS ( - 10. 97 ± 5. 22) % vs C - 18. 11 ± 4.43) %]. Aside from basel strain rates of NRCS, strain rates of all the other five segments of single ventricle were significantly lower than Corresponding segments of the control group [Median NRCS ( - 1. 21 ± 0. 42)s-1 vs (- 1.49 ± 0. 24)s-1 ;Apical NRCS ( - 1.10 ±0.41)s-1 vs (-1.47 ± 0.24)s-1;Basel RCS ( - 1.07 ± 0. 35) s-1 vs (- 1. 49 ± 0. 22) s-1; Median RCS (-0.97± 0.34)s-1 vs ( -1.48 ± 0. 20)s-1 (Apical RCS ( - 0. 93 ± 0. 39)s-1 vs ( - 1. 48 ± 0. 22)s-1]. Conclusions Longitudinal systolic ventricular function is impaired in children with functionally single ventricle. VVI can be used to asses ventricular systolic performance in children with functionally single ventricular.

Objective To investigate the current application status of reference intervals in routine chemistry and compare with the current health industry standards .Methods By using web-based external quality assessmentsoftware system , data were collectedfrom the laboratories which attended 2012 national reference intervals investigation , including the sources of reference intervals , upper and lower limits , subgroups and grouping rules , test methods, instruments and reagents , etc.Microsoft Excell2007 and SPSS 13.0 were used to analyze the trimmed data .Results There were 385 laboratories submitting the reference intervals they had been using .Only a few of laboratories'reference intervalsweregrouped .There are some differences in grouping rulescompared with the currentstandards .Even though some of the laboratories adopt the grouping rules as the same as the standards , there are still significantstatistical differences in reference intervals between the laboratories and the health industry standards (P <0.01).Conclusions The reference intervals of routine chemistry items suggested by the health industry standards have quite big differences from thoseused in current clinical laboratories dailywork ,that might be related from the population they served and many internal influence factors. If the health industry standards are used , the evaluation and validation of reference intervals should be done first.

Objective To summarize and analyze the results of national external quality assessment (EQA) of maternal serum prenatal screening in second trimester during 2004-2013,in order to provide a assistance for the quality improvement of the prenatal screening testing.Methods Five different concentration samples were distributed to each participated laboratories and were measured at each external quality assessment program during 2004 to 2013.The results reported in a specified time.The testing performance of alpha fetoprotein (AFP),total human chorionic gonadotropin (HCG),total β-human chorionic gonadotropin (β-HCG),free β-human chorionic gonadotropin (free β-HCG),unconjugated estriol (uE3) were evaluated.Results During 2004-2013,the number of laboratory participated increased from 57 to 500.The robust variation coefficient increased from 2.77％ to 18.98％ for AFP,5.6％ to 36.12％ for HCG,4.69％ to 24.38％ for β-HCG,2.66％ to 81.54％ for free β-HCG,and 3.83％ to 26.51％ for uE3.The percentage of passing rate reached 93％ (463/496) for AFP,66％ (35/53)for HCG,85％ (137/ 161) for β-HCG.The percentage of passing of free β-HCG (μg/L) increased from 52 ％ (24/46) to 94％ (248/264),but the passing percentage of free β-HCG (mIU/ml) were 47％ (18/38).The percentage of passing of uE3 reached 84％ (252/299).Conclusions The testing performance of AFP is best in prenatal screening,followed by β-HCG,other item testing have some problems.It is great important to improve the quality of maternal serum prenatal screening by strengthening external quality assessment and building comprehensive quality control system in China.