Holistic education is an important philosophy of medical education.Medical graduate students can show their skills of medical specialties,improve their abilities of communication and cooperation,and promote their sense of social responsibility through social practice.Through conducting questionnaire among medical graduate students of Peking University Third Hospital who major in internal medicine,we have got to know the effect of social practice on holistic education philosophy.Meanwhile,social practice is a crucial approach to implementing holistic education.

To accurately analyze metabolites in industry-important photosynthetic microbes, LC-MS based metabolomics protocol needs to be optimized specifically for individual species. In this study, an LC-MS based metabolomics method was optimized for cyanobacterium Synechocystis sp. PCC 6803. With the optimized extraction, liquid chromatographic and mass spectral parameters, the method was capable of detecting 24 important metabolites related to central carbohydrate and energy metabolism in Synechocystis sp. PCC 6803. The study laid an important foundation for the metabolomics analysis of cyanobacteria.
Chromatography, Liquid ; Mass Spectrometry ; Metabolome ; Metabolomics ; Photosynthesis ; Synechocystis ; metabolism

Objective To observe the lung protection of Astragalus membranaceus against radiotherapy to intermediate-stage and terminal thoracic neoplasm, and its influence on TNF-α and ET expression.Methods The patients with intermediate-stage and terminal thoracic neoplasm under radiotherapy were divided into a treatment group and a control group.Patients in the treatment group took 10 ml of Asragalus membranaceus twice a day.for consecutive 6 months from the beginning of radio therapy.TNF-α and ET in the plasma were measured before and after the radiotherapy.The clinical symptom,iconographic changes and lung diffusion were observed from the 15th day of radiotherapy.Results The TNF-α and ET in plasma afterthe radiotherapy were(2.48±0.75)as/ml and(69.32±23.03)pg/ml for the treatment group,and(5.12±1.01)ns/ml and(97.87±37.83)pg/ml for the control group with the statistial difference(x2=7.49,6.57,P<0.001).The decrease of CO diffusion 5 and 10 months after the radiotherapy in the treatment group was statistically different compared with that in the control group(x2=3.98,3.78,P<0.05).There was a statistical difference of the incidence of acute radiation pneumonitis and pulmonary fibrosis between these two groups(P<0.05).Conclusions Astragalus membranaceus could inhibit the excess expression of TNF-α and ET in plasma and reduce the deterioration of diffusion after radiotherapy,so that it can be used for intervention of lung injuries from radiotherapy.

Objective To assess the differences in carotid artery stiffness properties and endothelium-independent dilation (EID)between elderly and young patients,and evaluate the echotracking (ET)system for vascular stiffness at different ages.Methods A total of 79 outpatients with multiple cardiovascular risks were recruited.Clinical data including medical history,height,weight,blood pressure,fasting blood glucose and blood lipid were collected.We evaluated the arterial stiffness parameters of carotid artery and EID using an ultrasonic ET system in 46 elderly subjects,compared with 33 sex-matched non-elderly subjects.The impaired EID function was defined as brachial artery nitroglycerin mediated dilation (NMD)below 4％.Results All stiffness parameters including pressure-strain elasticity modulus stiffness index β (Ep),pulse wave velocity β (PWVβ)and augmentation index (AI)were significantly increased in elderly group compared with the non-elderly group [(138.9±64.7)kPa vs.(100.6±30.8)kPa,(10.9±4.7)vs.(8.2±2.3),and (6.9±1.4)m/s vs.(6.1±0.9)m/s,P＜0.05 respectively],while the exception of arterial compliance (AC)was reduced (0.9±0.3)mm2/kPa vs.(1.0±0.5)mm2/kPa(P＜0.05).The incidence of impaired EID in elderly group was higher than in non-elderly group [56.5％ (26 cases) vs.33.3％ (11 cases),P＜0.05].ET parameters including Ep,stiffness index β,PWVβ,AC and AI were related to age (r=-0.44,-0.45,-0.40,-0.40,0.34,all P＜0.01)； Ep,stiffness index β,PWVβ and AC were also related to impaired EDI (r=-0.38,-0.40,-0.34,-0.29,all P＜0.01).Conclusions Arterial stiffness properties and EID measured by ET system was more serious in elderly with multiple cardiovascular risks than in non-elderly subjects.As a convenient and accurate assessment of stiffness parameters,ET system is optimal option for measuring arterial stiffness and EID in elderly people.

Objective To assess the difference in left atrial properties between elderly and younger control subjects and the role of left atrium remodeling in patients of different ages with atrial fibrillation.Methods A total of 194 patients with non-valvular atrial fibrillation were enrolled from September 2014 to June 2016.Based on age,patients were divided into an elderly group (≥60 years,n=129) and a younger group (＜60 years,n=65).We evaluated remodeling parameters for the left atrium using an Ultrasound Cardiography (UCG) system in 125 elder subjects,together with 64 control subjects.All remodeling parameters were recorded,including left atrial diameter (LAD),left atrial square (LAS),left atrial pressure (LAP) and left ventricular end-diastolic dimension (LVEDD).Results The elderly group had more female patients and more patients with persistent atrial fibrillation.Meanwhile,scores of CHA2DS2Vsc and levels of N-terminal pro-brain natriuretic peptide (NT-ProBNP) were significantly increased in elderly patients (both P＜0.05).Moreover,the elderly group was associated with increased values of LAD and LAS[(39.1±4.4)mm vs.(37.1±5.3)mm,P＜0.01;and(23.3±4.5)cm2 vs.(21.4±4.8)cm2,P＜0.01;respectively],compared with those in the control group.Spearman's correlation analysis showed that LAD,LAS and LAP were all markedly related to age (r=0.213,P＜0.05;r=-0.175,P＜0.05;r=0.170,P＜0.05;respectively),persistent onset of atrial fibrillation (r=0.401,P＜0.05;r=0.446,P＜0.05;r=0.160,P＜0.05;respectively),and impaired heart function,measured by left ventricular ejection fraction (r=-0.4371,P＜0.05;r=-0.403,P＜0.05;r=-0.364,P＜0.05;respectively) and NT-ProBNP (r=0.485,P＜0.01;r=0.483,P＜ 0.01;r =0.293,P＜ 0.01;respectively).Conclusions Left atrial remodeling properties measured by the UCG system in the elderly with non-valvular atrial fibrillation are more serious than those in mid-aged and young subjects.As a convenient and accurate assessment of remodeling parameters,the UCG system is an excellent option for measuring left atrial remodeling in the elderly population.