This paper analyzed the main problems in the thesis of postgraduates with specialized master degree of public health.The problems existed were the poor quality of students,untargeted topics of the thesis and unsound evaluation system,etc.Specific measures were proposed for the construction of quality assurance system for postgraduates with specialized master degree of public health including four focus management,multiple evaluation system and post thesis evaluation.

ABSTRACT:Objective To explore the differential expression of microRNAs (miRNAs)in steroid-induced osteonecrosis (ON).Methods Bone tissues were selected from patients with steroid-induced ON between the necrotic zone of femoral heads and its femoral neck to analyze the miRNA expression profile using the microarray. The most differentially expressed miR-125a-3p and miR-1 7-5p in microarray analysis were further confirmed by real-time quantitative PCR.Results According to the microarray screening,8 miRNAs were upregulated and 3 miRNAs were downregulated in the necrotic zone of femoral heads samples (Fold>2,P <0.05 ).Results of real-time PCR revealed that miR-125a-3p was upregulated and miR-1 7-5p was downregulated in the necrotic zone of femoral heads samples,which were in agreement with the microarray data.Conclusion MiRNA’s differential expression profile of human steroid-induced ON samples was obtained.Among the differentially expressed miRNAs, miR-125a-3p and miR-1 7-5p are the most apparently differentially expressed miRNAs,which may be related to the pathogenesis and development of steroid-induced ON.

Objective: To investigate the effects of vitamin B 1, C and orange juice on human lung cancer cell proliferation in vitro. Methods: Vitamin C degradation in culture medium was evaluated. The methods included: methy thiazolyl tetrazolium (MTT) assay, colony forming assay and 3H TdR incorporation test. The final concentrations of factors in medium were: orange juice (vitamin C 30,60,120 ?g/ml), vitamin C(30,60,120 ?g/ml), vitamin B 1 (0.01,0.1,1 ?g/ml). Results: (1) In MTT test, orange juice at each level had significant inhibitory effect on the growth of lung cancer cells (P

Objective: To assay the content and stability of vitamin C(VC) in serum by a simple, specific method. Methods: Serum samples were extracted by metaphosphoric acid, and analyzed on a column C 18 of HPLC with DAD detector at 234 nm. Mobile phase was 100 mmol/L KH 2PO 4, pH3.00. The flow rate was 1 ml/min. Results: Under this condition, the retention time of VC was 5.76 min. The within run and between run reproducibilities tests were 0.42% and 2.11% respectively, and the recovery rate ranged from 82% to 88.5%. Stored at -70 ℃ and compared to that of its metaphosphoric acid extract, serum VC content was stable only for two days, and then decreased rapidly, whereas it did not decrease in metaphosphoric acid extract until the fifth day. Conclusion: A simple, sensitive and reliable method of HPLC with DAD detector is established for measuring VC in either serum or fruit, such as orange juice. VC should be determined immediately or should be extracted with metaphosphoric acid as soon as possible, then the extracts are kept at -70 ℃, and analysed within 5 d.

Objective To evaluate the outcome of percutaneous K-wire leverage reduction and fixation for O'Brien Ⅱ,Ⅲ pediatric radial neck fracture.Methods From March 2010 to February 2013,16 children with O'Brien Ⅱ,Ⅲ pediatric radial neck fracture were operated in our hospital.There were 6 females and 10 males aged from 6 to 14 years old.There were 12 left arms and 4 right arms.Concomitant injuries included proximal ulna fractures in 2 cases and medial epicondyle fracture of humerus in 1 case.All children present a swollen and painful elbow with loss of rotation and pain on pronation and supination.The mean visual analogue score (VAS) was 7.9 (range,6.5-9.2).The flextion,extention,pronation and supination of elbow were 78°±3°,-54°±4°,9°±3° and 5°±3° in average.All cases were classified by the O'Brien system,including 9 cases of Ⅱ type and 7 cases of Ⅲ type.Mechanism of injury was fall from a height.The interval between injury and surgery averaged 2.8 days.Percutaneous leverage reduction and fixation were performed for 16 patients.After confirming successful reduction,the wire was advanced to the far cortex of the radius and penetrated into the far cortex to maintain the reduction status.4 weeks of long-arm cast followed by functional exercises were carried out for all patients.We analyzed radiographs and clinical results according to the criteria suggested by Metaizeau.Results 16 patients were followed up for 11.8 month in average after operation.14 patients were gained anatomical reduction.No patient had posterior interosseous nerve injury,fracture redisplacement and pin site infection.All fractures healed in a mean of 4.1 weeks.The follow-up flextion,extention,pronation and supination of elbow were 136°±4°,-2°±2°,81 °±4° and 75°±4° in average.Follow-up radiographs showed no patient had avascular necrosis of radial head.One patient had physeal arrest after 15 months of operation and outpatient follow-up observation were conducted.According to Metaizeau function scale,8 were excellent,7 good and 1 fair.The healing rate was 93.8％ (15/16).Conclusion Percutaneous joystick reduction and fixation technique have good effect for O'Brien Ⅱ,Ⅲ pediatric radial neck fracture,which is simple and easy to master.

Objective To review our experiences of diagnostic methods and surgical treatment of the left superior vena cava (LSVC) draining into the left atrium.Methods Nineteen patients with LSVC draining into the left atrium were diagnosed and treated surgically from February 1998 to January 2012.All the cases were combined with other congenital heart diseases including patent ductus arteriosus,ventricular septal defect,atrial septal defect,single atrium,triatriatum,partial endocardial cushion defect,anomalous pulmonary venous drainage,right ventricle outflow stenosis,pulmonary valve stenosis,tetralogy of Fallot,double outlet right ventricle,complete endocardial cushion defect,tricuspid atresia.The patients were diagnosed through different methods including echocartiographic examination,cardiac catheterization,computer tomography,and explored during the operation,even postoperatively.All were treated surgically with four techniques including simple ligation to the LSVC,including ligation during a redo procedure; intra atrial rerouting to drainage the flow from the LSVC to the right atrium,atrial septum reconstruction to make the outlet of the LSVC lying in the right side of the patched atrial septal,and bidirectional Glenn shunt to get a physiological result.Results No mortality postoperatively.All the cases were uneventful postoperatively.And the main postoperative course was related only to the main diagnosis of congenital heart disease,not to the left superior vena cava draining into the left atrium.The echo examination result was satisfied before the discharge.The early and long term follow-up(1-11 years) results are excellent,no arrhythmia,no cardiac deficits after echo examination,including stenosis obstruction and residual shunt.No death.Conclusion The diagnostic methods of the LSVC draining into the left atrium are difficult,the only way to make the diagnosis clearly enough before the operation is depending on improving of more and more comprehending to this rare cardiac anomaly,by the pediatric cardiologists,the sinologist,the intensive care unit,and the pediatric cardiae surgeons.The choice of different surgical treatment is depending on the diagnosis and the findings during the operations,and the results are excellent after a suitable choice made.

Objective Exogenous small-diameter vascular grafts have been developed with tissue-engineered small-di-ameter vascular grafts for the reconstructive surgery in the treatment of patients with coronary artery diseases in whom restenosis of the initially transplanted autografts occurred.This study was conducted to develop decellularized umbilical arteries (HUAs) and evaluate their physical and mechanical properties,as well as to assess the usefulness of decellularized HUAs in the coronary artery bypass grafting procedures.Methods After HUAs were harvested,their inner diameters were measured with a sliding caliper and the blasting pressure was measured with a pressure gauge.HUAs were firstly infused with a compound liquid consisted of 0.25％ Trypsin and 0.01％ Ethylene Diamine tetraacetic Acid(EDTA) and then with 1％ Sodium Lauryal Sulfate (SDS).Fragments of the vessels were collected and observed under light microscope and electron microscope.The mechanical characteristics of HUAs were identified with an electronic experiment machine before and after decellularization.Fibroblasts and endothelial progenitor cells growing along the lining of decelluarized human umbilical arteries(dHUAs) could be observed.Results The average inner diameter of HUAs was ( 3.50 ± 0.55 ) mm.Two of thirty HUAs were broken at a pressure of 300 mm Hg.The process for the lining of HUAs to be decellularized with a peristaltic pump took 0.5 hour with 0.25％ Trypsin and 0.01％ EDTA and 3 hours with 1％ SDS.Observations with light microscope and electron microscope demonstrated that all of the original lining cells were decellularized.The ultimate stress of the HUAs did not change significantly after decellularization ( P ＞0.05 ).Attached fibroblasts and endothelial progenitor cells could be seen along the decellular lining of the grafts and the ultimate stress of the HUAs did not change significantly after implantation of the two kinds of cells.Conclusion dHUAs,with good histocompatibility and properties mentioned above,may be used as potential vascular grafts in CABG.

More and more DNA sequences have been obtained since the start-up of human genome project. Powerful system is badly needed for data mining on these DNA sequences. Based on a personal computer and Linux operating system, the Phred/Phrap/Consed software and Blast software were used to construct a platform for batch analysis of the sequences, including identifying raw DNA sequence from chromatogram file, vector sequence removing, contig analysis (sequence assembly), repeat sequence identifying and sequence similarity analysis. Result demonstrated that this robust platform could accelerate data analysis for large-scale DNA sequencing.

Objective To establish gastric bypass surgery model with SD rat and analyze the influence factors and preventive measures so as to accumulate experience and skills for further developing gastric bypass surgery model on diabetic rat( GK rat) . Methods Gastric by-pass surgery was operated on 30 SD rats. Summarized modeling experience and analyzed various factors affecting modeling success. Results 17 rats weresuccessfully survived after surgery and 13 failed, with the mortality rate 43. 3%. Three rats died during operation, including two for anesthesia and one for heart failure;one died due to anastomotic bleeding two hours after surgery. Eight died in the third day after surgery, including two for infection, two for intestinal necrosis, four for anastomotic stenosis or obstruction. One died because of anastomotic leakage caused by mistaking and satiety the fifth day after surgery. There were no other complications such as wound dehiscence occurred in this group . Conclusion Establishing models of gastric bypass surgery with SD rats which is regarded as pre-experiment of building models of gas-tric bypass surgery with GK rats is economical and feasible. Anesthesia and perioperative management, surgical techniques and infection pre-vention and control are the main factors affecting modeling. The survival rate of rat model could be increased if related factors well controlled.

Objective To investigate the protective effects of dexmedetomidine on lung injury during one lung ventilation in patients undergoing lobectomia pulmonalis.Methods Sixty-four patients undergoing lobectomy in our hospital from May 2014 to February 2017 were selected.There were 38 males and 26 females,aged 42-75 years,ASA physical status Ⅱ or Ⅲ.Patients were divided into two groups according to different treatments,n=32 in each group.The patients in the observation group were given dexmedetomidine 0.5 μg· kg-1 · h-1 at 20 min before the induction of anesthesia,and adjusted to 0.2-0.5 μg·kg-1 ·h-1 after 10 min.The control group was given equal volume normal saline.The changes of polymorphonuclear neutrophil (PMN),myeloper oxidase (MPO),intra-pulmonary shunt rate(Qs/Qt),xanthine oxidase (XOD),vascular endothelial growth factor (VEGF) and nitric oxide (NO) concent ration were recorded at 10 min before induction (T0),beginning of OLV (T1),OLV for 60 min (T2),90 min (T3),postoperative 24 h (T4).Results Compared with T0,the PMN counts increased significantly at T2-T4 and the serum MPO and XOD concentrations were significantly increased (P＜0.05).The PMN counts,serum MPO and XOD concentration in the observation group were significantly lower than those in the control group (P＜0.05).Compared with T0,the serum VEGF concentration was significantly increased at T2 and T3,and the serum VEGF concentration in the observation group was significantly lower than that in control group at T3 (P＜0.05).The serum NO concentration at T2 and T3 in observation group was significantly higher than that in control group (P＜0.05).Conclusion Dexmedetomidine can reduce the inflammatory response of the lungs and has a protective effect on ischemia-reperfusion and injury in patients with single lung ventilation,and reduce the degree of oxidative stress,which plays a protective effect on lung.