OBJECTIVE:To provide reference for evaluating the new round of essential medicine bidding and purchase policy in China,ensuring the stability of essential medicine supply and improving national essential medicine system.METHODS:Based on the theoretical analysis,taking Shanghai and Yunan province as sample,the questionnaire was designed to investigate the difficulty to implement essential drug purchase policy in essential medicine supply system,and the bidding situation evaluation of production enterprises by both sides of local drug bidding among staff in production enterprises,circulation enterprises,primary health care institutions and other institutions.The types of influential factors for the implementation of essential medicine purchase policy were determined finally.Factor analysis method was used to screen the key influential factors.RESULTS & CONCLUSIONS:Four common factors had a great influence on the implementation of essential medicine policy in China.The impact of the large to small is the rationality of the tender procurement program,the standardization of pharmaceutical production,the stability of demand for drug use and macroeconomic policy regulation and protection.It is suggested to further improve the drug recruitment system,select the products that have quality assurance and production specifications,and fully meet the diverse needs of the market,while provide relatively stable usage information for manufacturers.If necessary,"drug purchase with target quantity" of Shanghai model can be forced to carry out by policy so as to ensure that the interests of all parties in the pharmaceutical supply chain are treated fairly.

Objective To verify and monitor the performance of accuracy, precision and comparability of 26 clinical biochemical analytes (29 methods) in the six centers involved in multi-centers reference intervals research, and to ensure the reliability of theirmeasurement results.Methods During the period of the systems evaluating, two levels of commercial quality control materials and fresh frozen human serum reference materials were applied to verify the performance of inter-laboratory precision and accuracy of analysis systems. During the period of samples testing, the commercial quality control materials were measured whenever samples were analysed, the fresh frozen serum reference materials were measured once a month.The coefficient of variations (CVs), bias and total errors were calculated to assess the precision, accuracy and comparability.Results Verification of precision and accuracy: ( 1 ) the ranges of CVs of 29 methods in the six laboratory laboratories were 0.4%-6.0%, the CVs of all 29 methods met the criterion . (2) The overall average bias of the analysis systems of 21 analytes (24 methods) ranged from -5.15%( ALT) to 4.46% ( Ur ) .Among 24 methods the overall average bias of TP, Glu-GOD, Ur, Cl, Ca exceeded the acceptable range.The quality assessment during the period of samples testing:(1) The overall average bias ranged from -1.95%(Ca) to 2.92%(Ur), median 1.26%, they all met the requirements of relevant standards.( 2 ) When commercial control materials were tested, the requirements of CVs were fulfilled for most methods in the six laboratories,and the CVs of TP, Alb, Cl, Ca exceeded the acceptable range.The overall average TE of all methods met the quality specification for the C-N controls material.For the C-P control material, only the overall average TE of TP (5.05%) exceeded thearceptable range while the other methods met the requirement in criterion.Conclusions The performance of precision and accuracy of the analysis systems used in the six laboratories passed the verification.During the period of sample testing, the performance of precision and accuracy of the most methods in the 6 laboratories met the requirements of quality specifications, and the overall performance was good.Because of the limitation of current technology the performance of some methods didn't fulfill the requirement of specifications, and need to be improved.

Objective To investigate left ventricular (LV) strain in patients with hypertension (HT)and myocardial hypertrophy using three-dimensional speckle tracking echocardiography.Methods Myocardial movement was analyzed in 37 primary HT patients with myocardial hypertrophy and 27 healthy volunteers.LV longitudinal,circumferential,radial and area strains were measured.The correlation between each global strain parameter and LV ejection fraction (LVEF) was analyzed.Results LV global longitudinal strain(GSL),global radial strain (GSR) and global area strain (GSA) of HT patients with myocardial hypertrophy were significantly lower than the contrast group,whereas global circumferential strain(GSC) showed no significant difference between the two groups.Longitudinal,radial and area strains were decreased in LV basal and middle levels,while decreased circumferential strain was detected only in basal level.There were significant correlations between LVEF and GSL,GSC,GSR,GSA.Conclusions Impairment of LV regional myocardial contractility can be detected by three-dimensional speckle tracking echocardiography.

Objective To evaluate the value and characteristics of left ventricular global systolic strain and its relation to the left ventricular global systolic function in patients with myocardial infarction(MI) by three-dimensional speckle tracking echocardiography (3D-STI).Methods In 24 patient subjects and 20 control subjects,the myocardial motion was tracking by 3D-STI,left ventricular ejection fraction(LVEF),and global longitudinal peak systolic strain(LVGLS),global circular peak systolic strain(LVGCS),global radial peak systolic strain(LVGRS),global area peak systolic strain(LVGAS) were measured.The values were compared between the two groups,the correlations between LVEF and LVGLS,LVGCS,LVGRS,LVGAS were analyzed respectively.Results (1)There was significant difference of each index about LVEF and global strain between normal group and MI group (all P ＜0.05).(2)The correlations among LVEF and LVGLS,LVGCS,LVGRS,LVGAS were found (r =-0.626,-0.770,0.772,-0.748 respectively,P ＜0.01 for all).(3) Bland-Altman analysis showed there were good agreements in both patients with MI and control subjects.Conclusions 3D-STI could be applied non-invisibly and objective to assess alteration of myocardial global systolic function by accurately measuring strain.Therefore,3D-STI appears to be a reliable and useful tool to estimate the left ventricular systolic function of MI.

Objective To assess the two-dimensional carotid strain as an index of arterial stiffness in patients without carotid atherosclerotic plaques,and its clinic value in cardiovascular risk stratification.Methods All patients were divided into three groups (low risk,intermediate risk,high risk group) by Framingham cardiovascular risk scores,two-dimensional carotid circumferential strain (CS),carotid intimamedia thickness (IMT) were evaluated.CS was adjusted for pulse pressure (CS/PP).Results CS,CS/PP,IMT were significant difference between low risk and intermediate risk groups,low risk and high risk groups (P ＜0.05).IMT and CS were not significant difference between intermediate risk and high risk group (P =0.23,P =0.57).CS/PP was significant difference between three groups (P ＜0.05).Both CS and CS/PP were correlated with IMT (r =-0.30,r =-0.33,P ＜0.05).Conclusions Two dimensional strain could assess the carotid arterial mechanics.IMT and CS could evaluate the structural and functional alternations of carotid stiffness.Combining these two indices allowed more accurate evaluation of the subclinical phase of the atherosclerotic disease.

ObjectiveTo investigate the ability of three-dimensional(3D) speckle tracking imaging (STI) for assessing left ventricular (LV) strain,and measure the value and angle of myocardial main strain vector.MethoodsLongitudinal,circumferential and radial strain of LV were measured in 31 healthy adults by 3D-STI and two-dimensional(2D) STI.The main strain vector and the angle between main strain vector and the LV short-axis plane were calculated from longitudinal and circumferential strains.Results The global longitudinal,circumferential strains and strains at basal,middle,apical level of LV by 3D-STI were significantly smaller than those by 2D-STI,whereas radial strain showed an opposite trend.The 3D strains presented significant difference between different levels of LV,longitudinal,circumferential and radial 3D strains were greater at middle level than at basal and apical level of LV,meantime 2D stain didn't show such obvious trend.Calculated from three-dimensional longitudinal and circumferential strain,the main strain vector was greatest at middle level of LV,whereas the angle between main strain vector and LV short axis plane didn't show any significant difference between three levels of LV.Conclusions3D-STI provides us a new and reproducible method for the evaluation of LV regional function by measuring LV strains.

Objective To assess the usefulness of contrast echocardiography in differential diagnosing space-occupying lesions of the heart.Methods Contrast echocardiography was assessed for 38 patients of space-occupying lesion of the heart (SOLH).Contrast enhancement of SOLH was assessed visually,comparing with that in the adjacent myocardium:significant contrast enhancement,intensity higher than or equal to the adjacent myocardium; mild or partial contrast enhancement,intensity lower than the adjacent myocardium,or no contrast enhancement.Respectively,malignant tumors,benign tumors,and thrombus were diagnosed.Twenty-eight patients among the 38 cases had gold standard diagnosis.The consistency between visual assessment diagnosis and gold standards were compared with Kappa statistic.Results Visual semi-quantitative diagnosis of contrast echocardiography:thrombus,benign tumors and malignant tumors were diagnosed for 8,8 and 12 cases,separately.Except two highly vascular benign tumors (1rhabdomyoma and 1 paraganglioma) were misdiagnosed as malignant tumors,the rest 26 cases matched gold standard diagnosis.Quantitative analysis of contrast echocardiography,16 cases were suitable for quantitative an alysis,10 cases were diagnosed as benign tumors or thrombus (quantitative analysis could not differentiate the two),the rest 6 cases were diagnosed as malignant tumors.Quantitative analysis got the same 2 misdiagnosis as visual semi-quantitative diagnosis.Kappa value on visual semi-quantitative diagnosis of contrast echocardiography comparing with gold standard diagnosis was 0.892.Conclusions The characteristics of vascularity of SOLH can be accurately determined by the contrast enhancement level in diseased region through visual semi-quantitative analysis with contrast echocardiography.Contrast echocardiography can be mainly used in SOLH except thrombus that has been clearly diagnosed,especially for patients with on going or fore-past malignancy in other organs.

Objective To evaluate the features of carotid atherosclerotic plaques on ultrasonographic elastography. Methods A total of 45 atherosclerotie plaques of the carotid artery in 33 patients were found with routine ultrasonography, all the 45 atherosclerotic plaques were divided into soft plaque, fibrous plaque, mixed plaque and calcified plaque. The elastograms of the plaques were oberseved and the strain contrast(stiffness ratio) of blood tissue in common carotid artery to plaques were calculated. Results Seventeen soft plaques, 15 mixed plaques and 13 calcified plaques were founded using routine ultrasonography, but 0 fibrous plaques were founded. The soft plaques were shown in green, the mixed plaques were showen as mosaic of green and blue and the calcified plaques were showen in blue by ultrasonographic elastography. The strain contrast in patients with calcified plaques and mixed plaques were significantly higher when compared with the soft plaques group(P 0. 001, P <0.05). The strain contrast in patients with calcified plaques was significantly higher than the mixed plaques group (P < 0.001). Conclusions Ultrasonographie elastography could be used in carotid arteries atherosclerotic plaques. Various of acoustic characteristics plaques has different elastography and strain contrast.

Objective To evaluate the dyssynchrony of left ventricle in patients with coronary artery disease(CAD) by two-dimensional strain echocardiography (2-DS). Methods The myocardium of left ventricle of 33 patients with CAD and 30 nomal controls were detected by 2-DS. The time from onset QRS complexes to peak systolic longitudinal strain(Ts) and the standard deviation of Ts of 18 left ventricular segments (Ts-SD)were measured. Results There were 168 segments whose flow was provided by coronary artery with stenosis≤75% ,210 segments whose flow was provided by coronary artery with stenosis 75 %. ①Ts was delayed significantly and Ts-SD was obviously higher in patients with stenosis≥75% when compared with the control group. ②Ts was delayed and Ts-SD was higher in patients with stenosis≥75% compared with those whose stenosis was ≤75%. ③There were no statistical differences in Ts and Ts-SD between the patients with stenosis ≤75% and the control group. ④When left ventricular systolic dyssynchrony was defined as Ts-SD≥33.0 ms, there were 22 patients with systolic dyssynchrony of all 26 patients whose coronary artery stenosis≥75%, there were no patient with systolic dyssynchrony of all 7 patients whose stenosis ≤75%. Conclusions Although there are no evident regional wall motion abnormalities by routine echocardiography,in patients with severe coronary artery stenosis,2-DS can detect exactly the dyssynchrony of left ventricle.

Objective To assess the myocardial strain in patients with coronary artery disease by two dimensional strain echocardiography.Methods Forty-three patients with coronary artery disease and thirty five healthy subjects were included.High frame rate two-dimensional images were recorded from the left ventricular short-axis views at the levels of mitral annulus,papillary muscle and apex,and the apical four chamber view,two-chamber view and long-axis view of the left ventricle respectively.The longitudinal strain was measured in the apical views,radial strain and circumferential strain were measured in the left ventricular short-axis views using two-dimensional strain software.Results There were 96 segments whose flow was provided by coronary artery with stenosis＜75%,147 segments whose flow was provided by coronary artery with stenosis≥75%.The peak systolic longitudinal strain of different segments in patients with stenosis≥75% significantly reduced when compared with the control group(P＜0.05).The peak systolic radial strain and circumferential strain of different segments in patients with stenosis≥75% had no statistical difference compared with the control group(P＞0.05).When taking peak systolic longitudinal strain≥-16.1% as cut-off value for coronary artery stenosis of≥75%,the sensitivity and specificity were 78.7% and 76.4% respectively.There was no significant difference in systolic longitudinal strain,radial strain and circumferential strain between normal myocardium and stenosis＜75%(P＞0.05).Conclusions Although there are no evident regional wall motion abnormalities by two dimensional echocardiography,in patients with severe coronary artery stenosis,the longitudinal strain which can reflect the subendocardial myocardial function significantly reduced.