0.999 5), RSD were no more than 3.0%. The recovery rates were 98.0%-102.0%. There was no significant difference between the results of this method and EDTA-Na2 titration. Conclusion The method is rapid, accurate, simple, little disturbance and is acceptable in determination of total hardness in drinking water.

Objective:To examine the relationship between brain natriuretic peptide (BNP) and the recurrence of atrial fibrillation (AF) after successful electrical cardioversion (EC) by a meta analysis approach.Methods:Based on PubMed,Medline and China National Knowledge Infrastructure (CNKI) databases,related literatures,published from 1980-2008,were searched; a manual search was also performed.The included trials were analyzed by RevMan4.2 software for meta analysis.Results:Totally seven studies were finally included.The analysis revealed that the baseline BNP level were greater in patients with AF recurrence than those without AF recurrence,with the standardized mean difference in the BNP levels being 0.82 units (95% confidence interval 0.12 to 1.52).The test for overall effect Z-score was 2.30,with a P value of 0.02; there was significant difference.Conclusion:It is suggested that the higher BNP level after successful electrical cardioversion is associated with greater risk of AF recurrence.The level of BNP may serve as an indicator for AF recurrence after successful EC.

AIM:To study the effect of panax notoginseng saponins on the left atrial appendage(LAA)of the guinea pigs.METHODS:Standard microelectrode intracellular recording technique was used to record the LAA action potential(AP)and the effective refractory period(ERP)in the guinea pigs during the pouring with different density of PNS.RESULTS:The effect of PNS in concentration of 0.7,7,70,700 mg/L was significant at 20 min,the APD50 and APD80 of the pouring at 20 min,30 min,40 min of the 70 mg/L was longer than the reference group(P

Mid-ventricular hypertrophic obstructive cardiomyopathy (MVHOCM) is a rare type of cardiomyopathy thatcan be accompanied by apical aneurysm.We presented here a case report of MVHOCM with cornary artery disease.The sixty-fouryears old man was sent to hospital because of ventricular tachycardia.Large inversion T wave was showed on electrocardiography in the presence of abnormal coronary arteries and normal cardiac enzyme.Echoeardiogmphy showed an hourglass appearance of the leftventricle with an aneurysm in the apex and a pressure gradient between the outflow tract of left ventricle and the middle of the leftventricle was revealed by left-heart catheterization.

Objective To prepare totel glucosides in paeony(TGP) pellets by extrusion-spheronization and to optimize the formulation of TGP sustained-release pellets coated with Eudragit RS 100.Methods The TGP sustained-release pellets were prepared by mini Glatt fluidized bed coating method.The factors to influence the drug release behaviors and their properties were evaluated.Results The optimal TGP sustained-release pellet was shown significant sustained-releasing at the loading weight of copolymers of 6% and the plasticizer concentration of 10%.And the curves of cumulative drug release were fit for Peppas and Higuchi equation.Conclusion The pellets showed an obviously sustained-release effect.

To increase the rescue competency of residents, also the critical thinking, team dynamics, and the capability to handle with emergencies, Shanghai East Hospital developed a rescue course integrated with 24 standardized simulation cases learning and medical simulation education for residents training pro-gram. The instructor candidates should complete the simulation training and pass the instructor certification. Every course was monitored by the course director to ensure the teaching quality. After two and a half years of practice, it is found that the teaching of case teaching and simulation teaching is better than traditional teaching, and it plays an important role in the security of medical security.

Objective To approach the effects of full Marathon on striated muscle and renal function of Marathon amateurs without complaints. Methods A prospective self-paired design study was conducted. The amateurs without body discomfort, hematuria, brown urine, or persistent muscle pain within 1 week after the 2012 Xiamen International Marathon Race were enrolled voluntarily. The peripheral blood and random urine specimens of all subjects under static status 1 week before the race and after the race instantly (within 10 minutes after finishing the race) were collected to detect markers of renal function and striated muscle injury. Results Sixty-one subjects were included in the final analysis of the study with full Marathon of 42.195 km and mean race time of (297.05± 55.60) minutes. Compared with those under static status before the race, the markers of renal function including the levels of urinary N-acetyl-beta-D-glucusamidase [NAG (U/L): 64.00 (54.50, 85.50) vs. 9.50 (8.10, 11.50)], urinary β2-microspheres protein [β2-MG (μg/L): 261.00 (128.50, 1 608.00) vs. 66.60 (33.75, 123.00)], random urinary creatinine [UCr (μmol/L): 19 066.56±10 938.31 vs. 5 872.52±4 363.20] and serum creatinine [SCr (μmol/L): 129.97±25.84 vs. 97.39±14.51] immediately after the race were significantly increased (all P < 0.01); the markers of muscle injury including the levels of serum creatine kinase [CK (U/L): 864.00 (504.00, 1 644.00) vs. 164.00 (128.00, 256.00)], lactic dehydrogenase [LDH (U/L): 383.26±141.69 vs. 182.23±41.12], myoglobin [Mb (mg/L): 1 880.00 (1 080.00, 3 300.00) vs. 42.00 (36.00, 54.50)], alanine aminotransferase [ALT (U/L): 27.0 (19.5, 38.0) vs. 24.0 (15.0, 29.5)] and aspartate transaminase [AST (U/L): 52.07±25.13 vs. 28.28±11.86] were also significantly increased (all P < 0.01), and the increase in CK, Mb, and LDH were more significant. It was shown by correlation analysis that CK after race was negatively correlated with age (r = -0.352, P = 0.005) and body mass index (r = -0.271, P = 0.035), and it was positively correlated with racing time (r = 0.387, P = 0.002) and urinary β2-MG after the race instantly (r = 0.364, P = 0.004). Mb after race was negatively correlated with body mass index (r = -0.331, P = 0.009), and it was positively correlated with urinary β2-MG after the race instantly (r = 0.315, P = 0.013). LDH after race was negatively correlated with age (r = -0.275, P = 0.032) and body mass index (r = -0.377, P = 0.003), and it was positively correlated with urinary β2-MG after the race instantly (r = 0.424, P = 0.001). Conclusion Full Marathon could significantly impact striated muscle and renal function of Marathon amateurs without complaints.

Objective To prepare urokinase plasminogen activator (uPA)-loaded anionic lipid microbubbles (uPA-MBs) for thrombolysis with low-frequency ultrasound in vitro.Methods Anionic microbubbles composing of 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC),1,2-dipalmitoyl-sn-glycero-3-phospho-(l'-rac-glycerol) (DPPG),1,2-distearoyl-sn-glycero-3-phosphoethanol amine-N (succinyl PEG2000) (DSPE-PEG2000) and perfluoropropane (C3F8) were prepared by the mechanical vibration method.Then,the resulting anionic microbubbles were incubated with uPA.uPA-MBs were obtained via electrostatic adsorption.Bubble size and distribution were measured by particle size analyzer.FITC-labeled uPA-MBs were obtained and observed under fluorescence microscope.The surface potential of uPA-MBs and plain microbubbles (P-MBs) were detected by Zeta potential analyzer.Sodium dodecyl sulfonate-polyacrylamide gel electrophoresis (SDS-PAGE) was used for confirming the binding of uPA protein and anionic microbubbles.The encapsulation efficiency of uPA-MBs was determined by bicinchoninic acid (BCA) protein assay kit under three different dosages of uPA (10 000,50 000 and 100 000 U).The thrombolysis efficiency of uPA-MBs combined with low-frequency ultrasound was examined in vitro.Two-sample t test,one-way analysis of variance and Bonferroni test were performed to analyze the data.Results UPA-MBs were successfully obtained with the mean particle size of (1.76±0.29) μm.The surface potential of these bubbles was significantly higher than that of P-MBs:(-36.64±0.21) mV vs (-66.33±2.38) mV (t =21.538,P＜0.05).Fluorescence microscope showed a green shell of FITC-labeled uPA-MBs.The encapsulation efficiency of uPAMBs with the added dosage of 10 000 U was (42.01±2.02) ％,which was significantly higher than those of 50000 and 100 000 U ((33.24±1.95)％ and (33.10±1.65)％ respectively,F=22.340,P＜0.05).The thrombolysis efficiency by saline was (4.09±0.80)％,saline + ultrasound (8.50±1.48)％,MBs + ultrasound (14.27± 1.59) ％,uPA-MBs + ultrasound (35.72±6.31) ％ and uPA (16.87±0.46) ％,respectively (F =48.783,t =-8.613,-7.273,-5.942,-6.908,all P＜0.05).Conclusion Anionic microbubbles can successfully load uPA,and achieve significantly better thrombolysis effect when combined with low-frequency ultrasound.

Abstract Social media use and mental health problems in adolescents have long been a concern, but there is controversy in the conclusions on the direction of the relationship and the size of the effect. In order to clarify the relationship between social media and mental health, the paper mainly summarizes the concepts, mediating and moderating factors, as well as protective and risk factors, it also summarizes the limitations of past studies, so as to provide theoretical basis for future research directions.