Objectives:To compare the biomechanical characteristics of 3D-printed titanium alloy artificial vertebral bodies(AVB)with standard,self-stabilizing,and truss structures in spinal reconstruction after total en bloc spondylectomy(TES).Methods:A finite element model of the normal spine was constructed based on the CT data of the T10-L2 segments of a healthy adult male and was subsequently validated.The defect after vertebral column resection was simulated by removing the T12 vertebra,and three types of 3D-printed titanium alloy AVBs were implanted:standard(cylindrical),self-stabilizing(with two pairs of screws at the upper and lower ends),and truss(with bilateral ring holes for screw-rod connection).A 200N axial load and a 7.5N·m torque were applied using Abaqus software to simulate flexion,extension,lateral bending,and rotation movements.The overall stiffness of the"vertebra-prosthesis-vertebra"composite structure,the stress distributions on the posterior column connecting rod,the endplate,and the fusion device were analyzed.Results:The range of motion of the T10-L2 normal spinal finite element model established in this study was consistent with previous literature reports,therefore validating the model.Stiffness analysis showed that the displacement difference among the standard,truss,and self-stabilizing AVBs under the same load was 0.1mm,with the self-stabilizing structure AVB exhibiting the smallest displacement;The truss structure had smaller displacement in left-right bending.Stress analysis results indicated that the posterior column connecting rods of the three kinds of morphological AVBs bore the maximum Von Mises stress(174.90-175.00MPa)during rotation.Compared with the standard structure,the truss structure reduced the mid-segment stress of the posterior column connecting rod by 18.5％-24.3％during flexion-extension and lateral bending.Endplate stress analysis revealed that the maximum Von Mises stress on the endplate occurred during flexion,with values of 32.54MPa,30.76MPa,and 24.37MPa for the standard,truss,and self-stabilizing structures,respectively.The self-stabilizing structure reduced endplate stress by 14％-30％compared with the other two structures.Analysis of the internal fixation system showed that the cage stress of the self-stabilizing AVB was significantly lower than that of the standard and truss structures:reduced by 57％and 61％in flexion;52％-62％and 59％-64％in lateral bending;and 61％-62％and 46％-61％in rotation,respectively.Conclusions:Compared to the standard structure,the truss structure AVB reduces the stress concentration of the posterior column connecting rod through a multi-segment stress dispersion mechanism.The self-stabilizing structure AVB enhances the stability of the prosthesis-vertebral body interface through screw fixation.

Objectives:To compare the biomechanical characteristics of 3D-printed titanium alloy artificial vertebral bodies(AVB)with standard,self-stabilizing,and truss structures in spinal reconstruction after total en bloc spondylectomy(TES).Methods:A finite element model of the normal spine was constructed based on the CT data of the T10-L2 segments of a healthy adult male and was subsequently validated.The defect after vertebral column resection was simulated by removing the T12 vertebra,and three types of 3D-printed titanium alloy AVBs were implanted:standard(cylindrical),self-stabilizing(with two pairs of screws at the upper and lower ends),and truss(with bilateral ring holes for screw-rod connection).A 200N axial load and a 7.5N·m torque were applied using Abaqus software to simulate flexion,extension,lateral bending,and rotation movements.The overall stiffness of the"vertebra-prosthesis-vertebra"composite structure,the stress distributions on the posterior column connecting rod,the endplate,and the fusion device were analyzed.Results:The range of motion of the T10-L2 normal spinal finite element model established in this study was consistent with previous literature reports,therefore validating the model.Stiffness analysis showed that the displacement difference among the standard,truss,and self-stabilizing AVBs under the same load was 0.1mm,with the self-stabilizing structure AVB exhibiting the smallest displacement;The truss structure had smaller displacement in left-right bending.Stress analysis results indicated that the posterior column connecting rods of the three kinds of morphological AVBs bore the maximum Von Mises stress(174.90-175.00MPa)during rotation.Compared with the standard structure,the truss structure reduced the mid-segment stress of the posterior column connecting rod by 18.5％-24.3％during flexion-extension and lateral bending.Endplate stress analysis revealed that the maximum Von Mises stress on the endplate occurred during flexion,with values of 32.54MPa,30.76MPa,and 24.37MPa for the standard,truss,and self-stabilizing structures,respectively.The self-stabilizing structure reduced endplate stress by 14％-30％compared with the other two structures.Analysis of the internal fixation system showed that the cage stress of the self-stabilizing AVB was significantly lower than that of the standard and truss structures:reduced by 57％and 61％in flexion;52％-62％and 59％-64％in lateral bending;and 61％-62％and 46％-61％in rotation,respectively.Conclusions:Compared to the standard structure,the truss structure AVB reduces the stress concentration of the posterior column connecting rod through a multi-segment stress dispersion mechanism.The self-stabilizing structure AVB enhances the stability of the prosthesis-vertebral body interface through screw fixation.

Objective: To analyze Internet behaviors of children and adolescents and their influencing factors, and to provide scientific basis for health education guidance and prevention measures. Methods: A stratified cluster sampling method was used. From January to June 2019, 30 955 primary school students in 16 provinces (municipalities), from eastern, central, and western economic zones of China were selected to conduct a questionnaire survey, regarding general demographics, diet and exercise, tobacco, alcohol and sleep, Internet and electronics usage, etc. Results: Among them, 43.1% of students had never been online with girls (44.7%) higher than boys (41.8%)(χ2=21.04, P<0.01); 1.3% of students reported online time for more than 4 hours a day, boys were significantly higher than girls(χ2=15.87, P<0.01); Internet addiction was detected in 2.4% of elementary school students, with boys (3.0%) higher than girls(1.7%)(χ2=331.77, P<0.01), and the trend increases with grade. With sixth grade (3.3%) were significantly higher than children from the first grade (0.8%) and other grades(χ2=163.96, P<0.01). Children’s tendency to Internet addiction was 11.9%, of which boys were 13.0% and girls were 10.6%, boys were significantly higher than girls(χ2=117.66, P<0.01). Pearson correlation analysis revealed that, after controlling gender age, boarding school, family relationship, single parents and regrouped families, smoking, drinking sugary drinks, eating fried foods, and left-behind were positively related to Intenet addiction(r=0.06, 0.07, 0.27, 0.44, 0.07, 0.11, 0.09, P<0.01), while medium and high intensity sports, effective physical education, health education in school, AIDS education and parental restrictions on TV and computer games, were negatively associated with internet addiction(r=-0.74, -0.65, -0.04, -0.05, -0.63, P<0.01). Conclusion The internet addiction of Chinese primary school students is common and increases by year. High-intensity, high-density sports, effective physical education, and health education could help prevent Internet addiction among children.

Valproic acid is a first-line broad-spectrum antiepileptic drug, however, the pharmacokinetics of valproic acid are affected by many factors, such as heredity, drug combination and so on. So, how to realize the individualized dosing regimen of valproic acid has received much attention. Population pharmacokinetics combines classical pharmacokinetic principles and population statistical models to quantitatively evaluate the influence factor of drug concentration in the patient population. Thus, it can optimize characterization of the differences among individuals. This article reviews the researches about valproic acid in recent years, and summarizes the effect of the factors on the metabolism of valproic acid, such as drug combination and gene polymorphism. Additionally, focus on the latest research progress of individual administration of valproic acid under the guidance of population pharmacokinetics.

Objective:To study the influence of chloroquine combined with decitabine in the apoptosis of leukemia K562 cells and KG-1a1Aor1a cells,to explore the effect of autophagy on the leukemia cell apoptosis induced by decitabine,and to clarify its mechanism.Methods:The leukemia K562 and KG-1a1Aor1a cells were cultivated in vitro and divided into blank control group,decitabine group (10 μmol · L 1) and chloroquine (50 μmol · L 1) combined with decitabine group (combined group).The leukemia cells in combined group were pre-treated with chloroquine for 6 h before experiment.After treatment with drugs for 24 and 48 h,the number of cells was detected and by CCK-8 method the inhibitory rates of proliferation cells were calculated;the apoptotic rates and mitochondrial membrane potential were detected by flow cytometry.Q-PCR method was carried out to determine the gene expression levels of Atg7 and Atg12,and Western blotting was used to test the protein expression of LC3.Results:After treatment for 24 and 48 h,the number of K562 and KG-1a1Aor1a cells in decitabine group and combined group were decreased compared with blank control group (P＜0.05 or P＜0.01);the apoptotic rates and mitochondrial membrane potential were remarkably increased (P＜0.05 or P＜0.01).Compared with decitabine group,the number of K562 and KG-1a1Aor1a in combined group was significantly decreased,and the apoptotic rates were remarkably increased (P＜0.05).After treatment for 24 h,the expression levels of Atg7,Atg12 and LC3-Ⅱ/LC3-Ⅰ in the leukemia K562 and KG-1a1Aor1a cells in decitabine group were significantly increased compared with blank control group (P＜0.05 or P＜0.01);the expression levels of Atg7,Atg12 and LC3-Ⅱ/LC3-Ⅰ in the leukemia K562 and KG-1a1Aor1a cells in combined group were significantly decreased compared with decitabine group (P＜0.05 or P＜0.01).Conclusion:Decitabine could promote the apoptosis of leukemia cells,and the inhibition of autophagy by chloroquine can promote the apoptosis induced by decitabine.

Objective To investigate the relationship between the trauma severity and the usage of antibacterial drugs and to provide reference for standard protocol of proper antibiotic use in wound care.Methods ICD-10 and AIS were used to set up the relationship and to analyze the use of antibiotics in patients with different trauma score.Results 25 035 trauma patients were enrolled in this study.Those patients were divided into five groups according to the AIS score with least severe as group 1 to most severe as group 5.The patient percentage in group 1 to 5 was 21.92％,67.73％,8.86％,0.97％ and 0.52％ respectively.The five most frequently used antibiotic classes are second generation cephalosporins,third generation cephalosporins,first generation cephalosporins,fluoroquinolones and penicillin/beta lactamase inhibitor combination, accounted for 29.69％,22.57％,20.33％,4.66％ and 4.47％ of total DDDs of antibacterial drugs.Individually, the top 10 antibiotics are cefuroxime (12.21％), cefazolin (8.31％), ceftriaxone (7.74％), cefathiamidine (7.34％), cefotiam (4.87％), ceftazidime (3.68％), amoxicillin/clavulanic acid (3.63％), levofloxacin (3.59％), cefoxitin (3.56％), flucloxacillin (3.52％);gentamicin (2.27％), ornidazole (2.00％) and cefoperazone/tazobactam (1.44％) were used most in their categories respectively.The variety and quantity of antibacterial drugs used for different trauma patients were different.Conclusion The trauma score based on ICD-AIS can reflect the severity of trauma.The use of antibiotics in patients with different trauma score can provide reference for the clinical applications of antibiotics in wound care.

A new method was developed for the determination of 11 fat_soluble vitamins ( A, D, E and K) and its derivatives in vitamin tablets by ultra performance convergence chromatography ( UPC2 ) . The mobile phase was the mixture of supercritical CO2 and acetonitrile at a flow rate of 1 mL/min. The separation was carried out on the Waters Acquity UPC2 HSS C18 SB 100 mm × 3. 0 mm i. d. , 1. 8 μm column. The UV detector was set at a wavelength of 284 nm. The limits of detection ( LOD) were 1. 5-2. 0 mg/L, and the calibration linear for VK1 , VK2 , VK3 and VB3 was 3-300 mg/L, linear for VA, VA palmitate, VA formic acid, VE, VE acetate, VD2 and VD3 was 5-300 mg/L, respectively. Its spiked recoveries were 97. 31%-98. 76%, and the relative standard deviations ( RSDs) were 0. 41%-0. 96%. The method is applicable for the determination of fat_soluble vitamins ( A, D, E and K) and Their derivatives in vitamin tablets.

A method was developed for the determination of bifenthrin in tea by ultra performance convergence chromatography ( UPC2 ) . The samples were extracted with petroleum ether and cleaned up with Waters Sep-Pak:Carbon NH2 , and then detected by UPC2 . The mobile phase was the mixture of supercritical CO2 and acetonitrile at a flow rate of 1. 5 mL/min. The separation was conducted on a column of ACQUITY UPC2 TM BEH (100 mmí3. 0 mm,1. 7 μm). The UV detector was set at a wavelength of 220 nm. The detection limit was 20 μg/L. The linear range of bifenthrin was 0. 32-10. 30 mg/L. The recoveries ranged from 88. 7% to 98. 2%. The relative standard deviations (RSD) were from 1. 4% to 2. 8%. The result showed that the UPC2 was more efficient, rapid and low-cost than GC-MS. The method can meet the testing requirements of bifenthrin in tea. The efficacy of UPC2 on testing the concentration of bifenthrin in tea was compared with GC-MS based on National Proficiency Testing and the results were satisfactory.

To compare the concepts of pharmaceutical care and health management , analyze their internal connections both in present background and implementation process .Further development and practice of pharmaceutical care under the new health manage -ment model were discussed .

Objective To identify potential serum biomarkers specific for hepatocellular carcinoma (HCC).Methods Eighty-one patients wilh hepatitis B-related HCC and 80 healthy controls were randomly divided into a training set (48 HCC,47 controls) and a testing set (33 HCC,33 controls).Serum proteomic profiles were measured using surface-enhanced laser desorption/ionization time-offlight mass spectroscopy (SELDI-TOF-MS).A classification tree was established by the Biomarker Pattern Software.Candidate biomarkcrs were separated by HPLC and identified by MA1DI-MS/MS and database searching.Forty-eight patients with HCC,54 cirrhotic patients and 42 healthy subjects were clinically validated using candidate biomarkers by SELDI-Immunoassay.Real-time reverse transcriptase-polymerase chain reaction was performed to observe GRO-1 and Thrombin in 55 HCC tissues and 13 normal hepatolage tissues.Results Two up-regulated protein peaks were automatically chosen as a classification tree in the training set.These biomarkers were identified as thrombin light chain and CXC chemokines ligand 1 (GRO-1).The sensitivity and specificity of this classification tree were 89.6％.The multivariate model using the two biomarkers and alpha-fetoprotein (AFP) resulted in a sensitivity of 91.7％ and specificity of 92.7％,which was significantly better than AFP alone.The mRNA expression of GRO-1 and Thrombin were found in all HCC tissues.There were significant associations between GRO-1 gene expression and some clinical and pathological findings such as metastasis and recurrence (P＜0.05).Significant differences of 5-year survival rates wee observed among subgroups according to the expression of GRO-1 (P＜0.05).There were significant associations between Thrombin gene expression and some clinical and pathological findings such as recurrence and AFP (P＜0.05).Significant differences of 5-year survival rates were observed among the subgroups according to the expression of THROMBIN (P＜0.05).A positive correlation was found between GRO-1 and Thrombin (r=0.73,P＜0.01).Conclusion Thrombin light chain and GRO-1 are potential biomarkers of HCC.The expression of GRO-1 in HCC tissues was a valuable indicator in estimating metastasis and recurrence in HCC patients.