Electrocardiogram generation principle is the foundation of learning electrocardiogram and contains the knowledge system of the electrocardial vector,projection and lead system.Teaching contents should be appropriately selected according to the inner logic of the above three knowledge systems and the teaching rule.In classroom teaching,the knowledge of the lead system should be taught by step one,the knowledge of electrocardial vector should be taught by step two and the knowledge of projection should be taught by step three.The three steps help students understand and grasp the mechanism which causes the electrocardiogram more easily.

Objective To explore the use of lamivudine alone induced the poor response,especially the related factors of the occurrence of YMDD.Methods Retrospective analysis of 160 cases of the poor answering cases after lamivudine treatment,the baseline parameter values,the time appearing to the poor answering and the HBVDNA load in treatment were analyzed,to study their relationship with poor response.Results The lamivudine prolonged,the poor response to the probability gradually increase.The mutation rate in the 12nd month was 19.67％ and in the 36th month was 49.18％ ( P ＜ 0.05 ).Response to the many reasons,the YMDD mutation is the more common one.The relationship among HBVDNA load,ALT level on baseline and the rate of poor response emergence,the YMDD mutation rate was clear.By comparison in groups,the difference was significant (P＜0.05).Conclusion The lower baselins of ALT level,the higher of HBVDNA load,the greater probability of the poor response and the YMDD mutation.

Objective To evaluate CT and MRI findings of portal vein aneurysm(PVA)in order to improve its diagnostic accuracy.Methods CT and MRI findings of 9 patients with PVA proved by pathology and direct angiography were reviewed retrospectively.CT scanning was performed in 7 patients,including plain scan (n=2),both plain and enhanced scan (n=5),CT angiography (CTA)(n=3).Plain and enhanced MRI scan were performed in 3 patients.Results (1 )PVA showed a high predilection for old adults.(2 )Of the 9 tumors,4 located in portal vein trunk,2 located in junction of superior mesenteric vein and portal vein trunk,1 located in intrahepat-ic-extrahepatic portal vein,2 located in intra-hepatic portal vein.(3)8 tumors were characterized as well-defined and quasi-circular mass.1 patient occurred portal hypertension,thrombus as the portal vein trunk was oppressed by the tumor.(4)Plain CT showed the mass was slightly higher than pancreas parenchyma density,and uniform with the density of the liver parenchyma.Enhancement scanning showed 4 tumors represented mild or moderate enhancement in portal venous phase except for 1 patient accompany with portal vein thrombus.CTA showed clearly the relationship mass with portal vein,and classified the type of PVA .The 3 lesions represented hypo-intensity on T1 WI and even hyper-intensity on T2 WI.Enhancement scanning showed the tumor was significantly enhancement in portal venous phase on T1 WI.Conclusion CT and MRI have their own advantages in the diagnosis of portal vein aneurysm.Com-bination of CT and MRI could improve the diagnostic accuracy of portal vein aneurysm.

BACKGROUND: Osteogenesis-related molecules were detected in osteosarcoma tissues, which have closely association with the occurrence, development and prognosis of osteosarcoma. OBJECTIVE: To study the expression of bone morphogenetic protein 7 (BMP-7), vascular endothelial growth factor (VEGF) and core binding factor ?1 (RUNX2) in osteosarcoma cell Lines MG63. DESIGN, TIME AND SETTING: A molecular biology observation was performed at the Central Laboratory of Changhai Hospital between March 2007 and November 2007. MATERIALS: Osteosarcoma cell line MG63 was purchased from Institute of Biochemistry and cell biology, ISBS, CSA. METHODS: Cell line MG63 was counted with blood cell counting, inoculated in 100 mL culture flask with density of 1?104/cm2, stimulated at 37 ℃ with 5% CO2 air and saturated humidity. Then adherent cultured with DMEM containing 10% fetal bovine serum. When the cells reached 70%-80% confluency, the cells were digested with 0.25% pancreatic enzyme for 5 minutes, followed by terminating the digestion with adding DMEM containing 10% fetal bovine serum, and passaged at a ratio of 1:3. MAIN OUTCOME MEASURES: The expressions of BMP-7, VEGF and RUNX2 in MG63 were detected by RT-PCR and immunohistochemistry. RESULTS: BMP-7, VEGF and RUNX2 were positive expressed in MG63. CONCLUSION: The expression of BMP-7, VEGF and RUNX2 in MG63 was confirmed by gene and protein levels, which suggested that osteogenesis-related molecules may play important roles in the development of osteosarcoma.

Objective To evaluate the effect of montelukast combined with seretide in treatment of patients with asthma and its influence on balance between Th17 and Treg cells, and expression of IL-4 and IFN-γ.Methods 110 patients with asthma were randomly divided into observation group and control group, observation group of 55 cases, using montelukast combined with seretide, control group of 55 cases, using seretide,compared two groups of patients with pulmonary function changes, peripheral inflammatory factor changes and influence on Th17 and Treg cells balance. Results Before treatment, observation group and control group,FEV1 and FEV1 /FVC value was no significant difference.FEV1 and FEV1 /FVC after treatment were significantly improved compared with before treatment in two groups, differences were statistically significance (P<0.05).Between two groups, FEV1 values were significantly difference (t=8.1156, P=0.0001), FEV1 /FVC also had significant difference (t=4.8933, P=0.0001) .Before treatment, observation group and control group, IL-4 and IFN-γdid not have a statistically significant.After treatment, IL-4 and IFN-γdecreased significantly, with statistical difference compared with before treatment (P<0.05).Between two groups, IL-4 had significant difference (t=6.0273, P=0.0001), IFN-γalso had statistically significant (t=6.6042, P=0.0001).Before treatment, there was no significant difference between Th17 and Treg percentage, after 12 weeks of treatment and 24 weeks, Th17 in observation group were(0.53 ±0.02),(0.32 ±0.01), the control group were (0.78 ±0.03),(0.62 ±0.02), which had differences (P<0.05).After 12 weeks and 24 weeks,observation group Treg respectively(2.21 ± 0.22),(2.47 ±0.10),in control group were(1.50 ±0.11),(1.84 ±0.14), Treg percentage at different time after treatment, the differences had statistically significant (P<0.05).Conclusion Montelukast combined with Seretide in treating with asthma, pulmonary function of patients is obviously improved, and it can improve Th17, Treg cell.

Objective To explore the protective effect of resveratrol (RSV) on intestine barrier injury induced by hemorrhagic shock and its mechanism in rats.Methods According to random number table method,sixty-four SPF grade male Sprague-Dawley (SD) rats were divided into four groups:Sham operation group (only the catheters were indwelled in arterial and venous passages after anesthesia),hemorrhagic shock model group (model group,the catheters were indwelled in arterial and venous passages after anesthesia,and 0.3 mL solvent was administrated after hemorrhagic shock),RSV group (the catheters were indwelled in arterial and venous passages after anesthesia,15 mg/kg RSV was administered after hemorrhagic shock),superoxide dismutase 2 (SOD2) specific inhibitor,2-Methoxyoestradiol (2-ME) group (on the basic treatment of RSV group,0.1 mmol/L 2-ME was administered).The hemorrhagic shock model was reproduced by femoral artery bleeding.After drug administration,all rats were divided into two parts.One part was used for observations on 24-hour survival rate and survival time,while in the other part,2 hours after the hemorrhagic shock,the blood was collected for determination of the content of serum D-lactic acid,and afterward the rats were executed to obtain small intestine tissues for the examination of histopathological changes and Chiu's score.Moreover,differences of expression levels of tight junction proteins (Occludin,Claudin,ZO-1) of small intestine tissue and the oxidative stress related indexes SOD2 activity and reduced glutathione (GSH),oxidized glutathione (GSSH),malonaldehyde (MDA) contents were compared among the groups.Results Compared with the sham group,the model group demonstrated decreased survival rate,SOD2 activity,GSH content,GSH/GSSH ratio,reduced survival time,significantly increased serum D-lactic acid activity,Chiu's score and MDA content,and decreased expressions of tight junction proteins in small intestine tissue.Compared with model group,the RSV group showed significant increased survival rate [75.0％ (6/8) vs.37.5％ (3/8)] and prolonged survival time (hours:21.0±4.3 vs.10.4±5.8,P ＜ 0.05),significantly decreased serum D-lactic acid (μg/L:380.18 ± 70.59 vs.500.88 ± 97.53) and Chiu's score (1.75 ± 0.71 vs.4.00± 0.53) in small intestine (both P ＜ 0.05),obviously increased expressions of tight junction proteins,SOD2 activity,GSH and GSH/GSSG [Occludin (gray value):0.89 ± 0.10 vs.0.43 ± 0.77,Claudin (gray value):0.78±0.06 vs.0.33 ± 0.05,ZO-1 (gray value):0.83 ± 0.06 vs.0.34 ± 0.07,all P ＜ 0.05],and the elevated SOD2 activity (kU/L:0.85 ± 0.12 vs.0.51 ± 0.11,P ＜ 0.05],as well as increased GSH content and GSH/GSSG ratio [GSH (μmol/L):7.25±1.01 vs.3.86±0.54,GSH/GSSG:6.39± 1.14 vs.1.56±0.25,both P ＜ 0.05] in the small intestine,and markedly reduced MDA content (ng/g:5.00± 1.31 vs.8.63±0.92,P ＜ 0.05).Compared with RSV group,the 2-ME group demonstrated significantly decreased survival rate [50.0％ (4/8) vs.75.0％ (6/8)] and further shorter survival time (hours:12.2 ± 5.7 vs.21.0±4.3),increased serum D-lactic acid (μg/L:463.88 ± 60.16 vs.380.18 ± 70.59),obviously elevated Chiu's score (3.13 ± 0.99 vs.1.75±0.71,P ＜ 0.05),decreased expressions of tight junction proteins [Occludin (gray value):0.55±0.04 vs.0.89±0.10,Claudin (gray value):0.38±0.05 vs.0.78±0.06,ZO-1 (gray value):0.41±0.04 vs.0.83±0.06,all P ＜ 0.05];moreover,the activity of SOD2,GSH content,GSH/GSSG ratio were greatly reduced [SOD2 activity (kU/L):0.58 ± 0.13 vs.0.85 ± 0.12,GSH (μmol/L):4.49 ± 0.52 vs.7.25 ± 1.01,GSH/GSSG:1.57 ± 0.39 vs.6.39 ± 1.14,all P ＜ 0.05],and increased MDA content (ng/g:6.25 ± 1.04 vs.5.00 ± 1.31,P ＜ 0.05).The small intestine tissue was basically normal in Sham group,and no significant pathological changes were seen;in the model group,the small intestine epithelial mierovilli were collapsed and the mucosal barrier was destroyed obviously;in the RSV group the damages of small intestine microvilli and barrier were markedly alleviated;in 2-ME group the pathological changes were more evident compared with those in the RSV group.Conclusion RSV can improve intestinal barrier injury following hemorrhagic shock in rats;its mechanism may be related to SOD2 activation.

Objective To explore the practice teaching model of human anatomy through re-forming the practice teaching of system anatomy and regional anatomy. Methods Three classes of clinical medicine (5-year program) were randomly selected as reform experimental classes and the other 3 classes of the same grade were used as control classes. The teaching content of practice teach-ing was reformed in the experimental classes. In the system anatomy practice teaching, the teacher controlled the teaching process and developed the theme and requirements of each experimental class while the student completed the experiment developed by the teacher. In the regional anatomy practice teaching, students' interest in learning was stimulated by the content , which was related with the surgery, and the teacher guided students to complete the operation. In control classes, the forms of student observation as well as teacher answering questions and helping students were adopted. The student grading was divided into theoretical knowledge examination and specimen assessment and the achievement was analyzed by using a Simple Analysis of Variance (ANOVA) in SPSS 16.0. Results Compared with those of control classes, the scores of system anatomy and regional anatomy in experi-mental classes were significantly increased (80.7±5.8) vs. (67.4±17.4), (85.1±4.6) vs. (62.6± 12.4) and the theoretical scores of system anatomy were also improved significantly. But no significant difference in theoretical scores of regional anatomy was observed. Conclusions The teaching mode based on the practice teaching highlights the academic characteristics of the human anatomy, increas-es students' interest in learning and improves the effectiveness of practice teaching in human anatomy.

0.05).Conclusion Acupuncture has an effect on I/O curve amplitude of EPSP and PS,and on LTP induction of PS of dentate gyrus(DG) in rats after cerebral ischemia.However,the difference of effect of acupuncture at different doses on LTP induction is insignificant.

Objective To investigate the effects of hyperbaric oxygen preconditioning (HBOP) on brain edema, inflammatory reaction and neuronal cell apoptosis induced by experimental hemorrhage in rats. Method Eighteen male Spraque-Dawley rats, weighing 300 - 350 g,received five successive sessions of HBOP with 3 atmosphere absolute pressure and 100% O2 one hour daily for five successive days, and other eighteen rats received five successive sessions of pretreatment with one atmosphere absolute pressure, air, one hour daily for five successive days. Twenty-four hours after the final pre-conditioning, rats received an infusion of 100 μL autologous blood into the basal ganglion. Seventy-two hours later, rats were sacrificed for brain edema measurements in 12 rats of each group. The histopathological changes around the hematoma were observed microscopically, and the neuronal cell apoptosis was detected by using the terminal deoxynucleotidyl transferase-mediated nick end labeling (TUNEL) in six rats of each group. Data of brain water content were analyzed by using Stata 7.0 software and statistical analysis was carried out by two-tailed Student t -test. Results Compared with the control group, HBOP significantly attenuated brain edema 72 hours after intra-cerebral hemorrhage in experimental rats (81. 6± 0. 7% vs. 82. 8± 0.9%, P < 0.01). Inflammatory cell infiltration and neuronal cell apoptosis were also significantly decreased in the HBOP group. Conclusions HBOP protects the rats against brain edema formation, and quells inflammatory reaction and neuronal cell apoptosis following intra-cerebral hemorrhage in experimental rats.

Objective To identify whether the helper T lymphocyte 1 (Th1)/helper T lymphocyte 2 (Th2) of patients' serum and bronchoalveolar lavage fluid (BALF) at admission could represent the severity of idiopathic pulmonary fibrosis (IPF) and whether its change at six months could predict the progression of the disease.Methods Eighty-three patients with IPF were subjected to pulmonary function tests (PFFs),dyspnea scores,arterial blood gas analysis,six-minute walk test (6MWT) and high-resolution computed tomography (HRCT).The serum and BALF specimen of these patients were obtained as well as 20 control serum and 10 control BALF specimen.A total of 55 patients were followed up,and their BALF and serum levels of interferon γ (IFNγ) and IL-4 were detected by enzyme-linked immunoadsorbent assay (ELISA).The correlation between the IFNγ/IL-4 levels (at admission and the change of that at six months follow-up) and the clinical,physiological and image features in the IPF patients were analyzed.Results The baseline serum and BALF level of IFNγ/IL-4 (0.8 ± 0.3) in the IPF patients was lower than that in the control group (1.4 ± 0.2),which showed significant correlation with the course of disease,dyspnea scores,FEV1 ％,FVC％,TLC％,maximum desaturation,6MWD and CT-fib (all P values ＜ 0.05).The serum level of IFNγ/IL-4 showed positive correlation with CT-alv (r =0.340,P ＜ 0.01).During follow-up,no statistic difference was found in the serum levels of IFNγ,IL-4 and IFNγ/IL-4 between the IPF patients with or without glucocorticoids treatment.There were significant aggravation in the dyspnea scores,FEV1％,FVC％,CT-alv,CT-fib,IFNγ and IL-4 at six months follow-up.Significant correlation had been showed between the change of the serum IFNγ/IL-4 level with the changes of the dyspnea scores,FVC％,TLC％,DLCO％,6MWD and CT-fib in the IPF patients (P ＜0.05).Conclusions There are disequilibrium of the Th1/Th2 in the serum and the BALF of the IPF patients.The Th1/Th2 level could represent severity of the disease,and the serum level change of Th1/Th2 in the follow-up could predict the progression of the diseases in the IPF patients.