Objective:This paper investigates the difference of chronic disease in different social class of the elderly in Beijing .Method: Date of a representative sample included 1717 residents aged 60 and above are drawn from Beijing elderly household survey 2013 conducted by Peking university school of public health .With income , ed-ucation , occupation and residence household as indicators of social class , logistic regression model is used for analy-zing the difference of chronic disease prevalence among different socio-economic status .Result:The non-agricultural household group , middle and highest income group , the least and highest groups of education have a lower probability and the farming , forestry, animal husbandry and fishing water production personnel before retired have a higher risk of suffering from chronic disease .In terms of multiple chronic diseases , second lowest 20%income group tie to high-er risk of suffering three or more chronic conditions simultaneously .Conclusion: Strategies development of chronic disease prevention and control should take full account of social determinants of health such as the social stratifica -tion , not just for the direct cause of chronic diseases .Agricultural household , low-income and low-education group of people should be priorities in Beijing elderly chronic disease prevention and control .

Objective: To construct a core competency training indicator system for high-level public health talents using the Delphi method, so as to provide insights into optimization of high-level public health talents training. Methods: Based on review of publications pertaining to core competency training for high-level public health talents, in combination with public health priorities and development needs in China, a preliminary indicator system was constructed. Twenty public health experts were invited for two rounds of Delphi expert consultation. Indicators were screened based on the frequency of full marks, mean score and coefficient of variation (CV), and the weight of indicators was determined using the Entropy weight method. The effectiveness of the Delphi expert consultation was evaluated using the active degree, authority coefficient and the consistency degree. Results: Twenty experts participated in the consultation, including 12 men, and there were 6 experts at ages of 30 to 39 years, 8 at ages of 40 to 49 years, and 6 at ages of 50 years and older. There were 17 experts with an educational level of master and above, 19 with senior professional titles and all experts had working experiences for 10 years and longer. The active degrees were 95.24% and 100.00% for two rounds of consultations, and the overall authority coefficient was 0.87. Following two rounds of consultations, all CVs were reduced to below 0.25, and the coordination coefficients were all statistically significant (P<0.05), with a higher coordination coefficient in the second round of consultation than in the first round. The constructed core competency training indicator system for high-level public health talents included four primary indicators, including health protection, health service improvement, health promotion, and essential quality, with weights of 0.388, 0.310, 0.122 and 0.180, 11 secondary indicators, with high weights seen for protection of human health from threats (0.178), monitoring and assessment of health service utilization (0.157) and promotion of health service quality and access (0.112), and 70 tertiary indicators, with high weights seen for Chinese writing (0.038), capability for health policy suggestions (0.034) and global perspective (0.030). Conclusion The core competency training indicator system for high-level public health talents constructed in this study may provide insights into training of high-level public health talents.

Objective:To probe the method of isolating outer hair cells (OHC) from each of four turns of the guinea-pig cochlea. Method:From eight guinea pigs the organ of Corti from each of four turns of the cochlea were dissected, and then treated using enzyme. Result:A fair amount of living OHCs from each of four turns were obtained. The length of OHCs from each of four turns were 23.81,34.50,60.48 and 71.37 μm. Conclusion:The key to success in isolating OHCs from each of four turns of the cochlea is to know very well the anatomical characteristics of each of four turns of the cochlea and be operated in accordance with normal rules.

Objective:To observe the bone regeneration capacity of bone defects around BLB implants covered with or without membranes.Methods:Implants were installed into femoral bone of grown-up dogs.Near implants,3 mm horizontal width,5 mm vertical depth and 1,2,3,4 mm horizontal length(along the macroaxis of femoral bone) standard gradient bone defects were made.On one side,the incisions were directly sutured by lamination,and on the other side the incisions were sutured by lamination after using collagen membrane to cover on the defects.Three months after the operation the specimens were observed by stereomicroscopy.Results:In the groups with 1,2 and 3 mm defects,the defect areas had been filled completely with new bone which was mainly compact cortex.In the group with 4 mm defects,the defect areas were filled with new bone which was mainly trabecular bone.Bigger lacunes could be observed in the groups without membranes.Conclusion:If the defect is less than 3 mm,whether bioresorbable collagen membrane is used or not,osseointegration is well in the implant-bone interface.Improving bone regeneration should be done when the bone defect extension is bigger.

Objective To investigate the diagnostic value of UL-16 binding protein 2 (ULBP-2,macrophage inhibitory cytokine-1 (MIC-1) for pancreatic cancer.Methods The serum samples of 152pancreatic cancer patients,20 precursors of pancreatic cancer,91 chronic pancreatitis patients and 96 age/sexmatched healthy persons were collected.The serum ULBP-2 and MIC-1 levels were determined by using the ELISA kit and were compared with level of CA19-9.A receiver operating characteristic (ROC) curve was constructed to evaluate their diagnostic values for pancreatic cancer.Results The serum levels of ULBP-2 in patients with pancreatic cancer,precursors of pancreatic cancer,chronic pancreatitis and healthy persons were (219.9 ± 182.5),(62.6 ± 11.4),(68.4 ± 36.8),(76.5 ± 40.9) μg/L,the corresponding values of MIC 1 were (3521.3±3903.4),(973.6±589.0),(959.6±879.0),(427.6±317.0) μg/L,while the corresponding values of CA19-9 were (1448.8 ± 3707.0),(12.0 ± 9.3),(38.2 ± 139.0),(7.7 ± 5.0)kU/L.The parameters in pancreatic cancer patients were significantly higher than those in control group (x2 =40.628,71.662,45.505,15.827,36.433,63.494,26.264,73.427,49.088,P ＜ 0.01).The area under ROC curves(AUC) of ULBP-2,MIC-1,CA19-9 were 0.909,0.864,0.818,and ULBP-2 was superior to CA19-9 and MIC-1,however the combined measurement of three markers produced the highest diagnostic yield(AUC =0.982).For early stage pancreatic diseases (precursors to pancreatic cancer and IA stage pancreatic cancer),AUC of ULBP-2,MIC-1,CA19-9 were 0.506,0.837,0.684,MIC-1 was superior to ULBP-2 and CA19-9,however the combined measurement of MIC-1 and CA19-9 produced the highest diagnostic yield(AUC =0.897).Conclusions Serum ULBP-2,MIC-1 levels are significantly elevated in pancreatic cancer patients.The combined measurement of ULBP-2,MIC-1 and CA 19-9 can increase the diagnostic yield for pancreatic cancer.

Objective To establish a method for measuring serum cotinine by isotope dilution liquid chromatography tandem mass spectrometry (ID-LC/MS/MS) and provide an assay that can be applied to theevaluation of the level of smoke exposure and to the risk analysis of smoking related diseases.Methods Blood samples were collected from 94 apparently healthy subjects from October to December in 2010 and centrifuged,and the sera were separated.Serum samples were mixed with [ D3 ] -cotinine ( as the internal standard) and treated with acetonitriles to precipitate protein.After centrifugation,the supernatants were transferred and evaporated under a stream of nitrogen until dryness and reconstituted with mobile phase.Then the residuals were analyzed by LC/MS/MS system with multiple reaction monitor model; the concentration of cotinine were quantified by the isotope internal standard method and the stand curve was employed with a series of calibration.To estimate the precision of the method,five frozen serum pools were repeatedly analyzed in five runs,and every pool was analyzed in triplicate.In addition,the recovery rates were analyzed with the serum sample added with different levels of standard.The stability of cotinine in serum preserved at room temperature,4 ℃ and - 80 ℃,respectively.Finally,the levels of cotinine of 94 healthy subjects were measured to evaluate the distribution of cotinine with different smoke statuses.Results Serum cotinine measured by ID-LC/MS/MS was separated well with few interferences.The correlation coefficients between the peak area ratios and cotinine concentrations were higher than 0.9993.The values of within-run coefficients of variation (CV) of five frozen serum pools (0.68,48.42,94.34,250.95 and 287.04 μg/L) were 2.19％,0.78％,0.75％,0.65％ and 0.67％,respectively.The values of total CV were 4.71％,1.40％,1.98％,1.10％ and 1.03％,respectively.The limit of detection (LOD) and limit of quantitation ( LOQ ) were 0.013 and 0.050 μg/L,respectively.The analytical recoveries ranged from 99.22％ to 102.67％.The samples could maintain stability within 2 d at room temperature,7 d at 4 ℃ and 3 months at -80 ℃ resulting the accuracy of measurements from 99.28％ to 100.87％ and the CV＜5％.The levels of cotinine of 94 healthy subjects were measured and shown skewed and leptokurtic distribution.The concentrations of twenty smokers,fourteen former smokers and sixty non-smokers were 116.40 (63.17 -241.12),0.67 (0.15 - 0.95 ) and 0.22 (0.15 - 0.42 ) μg/L,respectively.Furthermore,the level of cotinine of former smokers (Z =-2.12,P ＜0.05) and smokers (Z =-6.67,P ＜0.001) were statistically higher than non-smokers.Conclusions An ID-LC/MS/MS method for serum cotinine detection has been established.It is hoped that the method will be applied to the assessment of smoke exposure and its association with the risks of smoking related diseases since it is simple,specific,precise,sensitive and accurate.

Objective To investigate the mechanism of venous reverse-flow flap in the differentperiod after operation.Methods The rabbits wero randomly allocated into 3 groups.In group A,including saphenous artery and venae commutante.In group B,saphenous artery without venae commutante.In group C,surface seeping and saphenous artery and venae commutante.Flap appearance,intravenous pressure,vessel diameter,mierocircular and histological examination were mea8ured.Results The difference of introvenous pressure between group A.B and C was obvious.Reverse flow WaS found in group A and C group through microcirculation observation 2 hours post-operation.Venous valve lose efficacy while the vessel diameter wes at maximum just after the pressure peak.Conclusion Venous retrograde return in reverse-flow island flaps can be achieved more easily through"incompetent valves route"than through "communicating and collaterall by pass route".By pass route is a supplementary way.Surface seeping Can slighfly relieve the venous pressure but can cause infection.

Objective:To study the association of air pollution with health service demand of the elderly and middle-age patients with cardiovascular and cerebrovascular diseases,and to provide a scientific ba-sis for development of environmental protection policy and health service policy of the Chinese govern-ment.Methods:This study included survey data on self-evaluated health,outpatient service demand and inpatient service demand of the patients with hypertension,heart disease and stroke in 62 cities of 1 7 provinces from China Health and Retirement Longitudinal Study(CHARLS)in 201 1 and 201 3,and com-bined it with the data on the annual concentrations of inhalable particulate matter(PM1 0 ),sulfur dioxide (SO2 )and nitrogen dioxide(NO2 )of those provinces and cities.Conditional Logistic regression was car-ried out to assess the possible effects of air pollutants on self-evaluated health and health service utiliza-tion.Results:The results showed that turning points existed in the effects of concentrations of NO2 and SO2 on the health service demand of the patients with hypertension,heart disease and stroke.The inpa-tient service demand of the hypertension patients increased with NO2 concentration when it was lower than 35.1 μg/m3 and decreased with NO2 concentration for higher value.Self-evaluated health of the patients with heart disease and stroke decreased with SO2 concentration when it was lower than 63.8 μg/m3 and increased with SO2 concentration for higher value.In addition,no evidence was found for the association between PM1 0 and health service demand.Conclusion:Air pollution may have effects on health service demand of the patients with hypertension,cardiovascular and cerebrovascular diseases,and different air pollutants at high or low concentration may have different health effects.

Objective To develop an HPLC method for the measurement of n-3 fatty acid index of serum cholesteryl esters.Methods Serum triglycerides were hydrolyzed with ethanolic sodium hydroxide and cholesteryl esters (CEs) were extracted with hexane.The extracted CEs were analyzed by reversed phase HPLC with a UV detection at 205 nm.Cholesteryl eicosapentaenoate and docosahexaenoate ( major n-3 fatty acid cholesteryl esters) were identified by liquid chromatography-tandem mass spectrometry and cholesterol in each CE fraction was measured.Peak areas of CEs were corrected for cholesterol and CE n-3 index was calculated using the corrected peak area and expressed as the percentage of n-3 fatty acid CEs in total CEs.Results The HPLC analysis can be finished in 6 minutes.Triglycerides which interfere with the determination of n-3 fatty acid index, were hydrolyzed with ethanolic sodium hydroxide (4 mol/L) in 30 seconds.The within-run and total CVs for CE n-3 index averaged 0.66% and 0.90%, respectively.CE n-3 indexes of 70 volunteers and 36 coronary heart disease patients apparently healthy subjects and patients with coronary heart disease in Beijing Hospital appeared to be positively skewed and leptokurtic distribution ( skewness = 1.25, kurtosis = 1.70 ).The median of n-3 indices were 0.98% ( 0.37% - 2.40% ).The logarithm of n-3 index appeared to be normal distribution and the average is 0.003 7% with standard deviations of 0.15.The distribution of n-3 indices of gender groups was similar with the total.The medians of females and males were 1.08% (0.60% -2.40%) and 0.95% (0.37% -2.11%) respectively, and the former were significantly higher than the latter( t = - 3.021, P = 0.003 ).Conclusion A new method for the measurement of n-3 index of serum cholesteryl esters by HPLC has been established.It is simple and precise and can be used in predicting cardiovascular diseases risks and monitoring dietary intake of n-3 fatty acids.

Objective:To verify the accuracy and feasibility of radioactive 125I seed implantation assisted by an optical navigation system and a 3D-printing non-coplanar template in the treatment of recurrent head and neck cancers. Methods:A total of 12 patients with recurrent head and neck cancer treated with radioactive 125I seed implantation assisted by an optical navigation system and 3D-printing non-coplanar template were enrolled from Dec 2018 to Dec 2019.The pre-plan and post-implant implantation needle number and implanted seed number were recorded.Meanwhile, their dosimetric parameters were compared, including D90, minimum peripheral dose (MPD), V100, V150, V200, conformity index (CI), external index (EI), and the homogeneity index (HI) of the target volume. Results:The median lesion volume was 31.5 cm 3, the median number of seeds was 61.5, and the median prescription dose was 130 Gy.The means of the pre-plan D90, MPD, V100, V150 and V200 were 134.2, 64.6, 93.3, 75.3 and 39.3 Gy, respectively, while those of post-implant D90, MPD, V100, V150, and V200 were 146.7, 68.94, 97.47, 80.40 and 48.30 Gy, respectively, with no statistically significant difference ( P>0.05). Meanwhile, there was no statistically significant difference between the pre-plan and post-implantation needle number, implanted seed number, CI, HI, and EI ( P>0.05). In terms of postoperative dose quality assessment, eight cases were rated excellent (66.6%) and four cases were rated good (33.3%). Conclusions:Radioactive 125I seed implantation assisted by an optical navigation system and 3D-printing non-coplanar template can be accurately performed in the treatment of recurrent head and neck cancer, with good consistency between pre-plan and post-implant dosimetric parameters and thus of prospective potential in clinical application.