Both the lecture based learning mode and problem based learning mode have their advantages and disadvantages in imparting knowledge and cultivating students'ability.Therefore according to the characteristics of clinical education,two kinds of methods should be used together to complement each other in clinical education of surgery so that knowledge can be systematically imparted to students through lecture based learning,and the abilities such as self-study,oral expression,cooperate and innovation can be cultivated through problem based learning to improve the quality of education.

Objective To study the CT characteristics of rare renal malignant tumors.Methods 7 cases with rare renal malignant tumors confirmed by operation and pathology were reviewed and their CT manifestations were analyzed retrospectively.In clinical, all cases had abdomen pain,6 cases had macroscopic haematuria,and 1 case had asymptomatic by chance.Results Of 7 cases,3 ca-ses were sarcomatoid carcinoma,1 case was carcinosarcoma,1 case was malignant mesenchymal tumor,1 case was lymphoma,and 1 case was neuroendocrine carcinoma.The diameter was about 4.0-12.3 cm.1 case had uniform density,6 cases uneven,and the boundary was not clear.Conclusion The rare renal malignant tumors are misdiagnosed easily.Combined clinical data with imaging performance are helpful to make comprehensive analysis,and to improve accuracy rate for diagnosis,definite diagnosis still depends on pathological examination.

"3+2" educational model was performed in our clinical medical college as a reformation based on traditional "4+1" model.After 5 years teaching practice,it obtained some good results as we prospected,however,there still exists some problems.This article analyzes the problems around the aspect of the teachers,the students,the teaching administration and arrangements,and proposes the corresponded measure to improve it.

Objective To test the effect of different flexion angles of knee joint on the myoelectric activity and torque of quadriceps femoris and hamstring muscle when these muscles contracting.MethodsElectromyographic activities and isometric torque measurements were performed on 10 healthy subjects at 30°, 60° and 90° of knee joint flexion.ResultsThe results indicated that the greatest maximal voluntary isometric contracture-torque of quadriceps femoris occurred during knee extension at 60° of knee flexion ( P<0.01). However, no significant relationship of maximal voluntary isometric contracture-electromyography and maximal voluntary isometric contracture-torque of quadriceps femoris were found in 10 subjects. But when knee joint was at 90° flexion, hamstring muscle had a greatest neuro-myoelectric activity.ConclusionThe exercise of maximal voluntary isometric contraction of quadriceps femoris and hamstrings muscles at certain knee joint angle can help to maintain the stability of knee joint.

AIM: To explore the characters of fibroblast-like (F-L) cells cultured from granunocyte clony stimunating factor (G-CSF)-mobilized peripheral blood cell (PBC) harvests. METHODS: The adherent cells in the PBC harvests were cultured for 2 week in the mediums of RPMI-1640/L-DMEM/G-CSF or interleukin-3 (IL-3) plus RPMI-1640, the cultured F-L cells were analyzed by flow cytometry (FC). RESULTS: The adherent non-confluent F-L cells obtained from the four groups were similar in their phenotypes: CD33+, CD11c+, CD64+, CD14+, CD45+, HLA-DR+, CD86+, CD34-, CD38-, CD3-, CD19-, CD56-, CD29-, CD44-, CD105-. The F-L cells are similar to monocytes except CD38-and were distinct from dendritic cells (DC) or mesenchymal stem cells (MSC). CONCLUSION: The cultured F-L cells are macrophages rather than DC or MSC. G-CSF, rhIL-3 enhances their numbers.

Objective To evaluate the result of fresh autologuos pericardium for the reconstruction of new pulmonary arterial root in arterial switch operation (ASO). Methods Between January 2004 and June 2010, 63 consecutive infants with congenital heart disease were treated with ASO. A new pulmonary arterial root was reconstructed with a fresh autologuos pericardium which clipped pants-like. The followed up time was 3 months to 6 years after discharge. Patients were reexamined consecutively at 3- and 6-month; 1-, 2- and 6-year. Two-dimensional echocardiography was performed for measuring the pulmonary artery diameter. The pulmonary arterial blood speed was measured by continuous Doppler during systole. The pulmonary flow and the pulmonary artery diameter of healthy children of same age were also measure as control group. Simplified Bernoulli formula was adopted to calculate the pressure gradient through pulmonary artery anastomose for, evaluating whether it had pulmonary stenosis or not. Results Fifty seven infants were cured and discharged. Forty nine patients were finished follow up with a mean duration of( 18 ±4) months. The blood speed in the pulmonary artery anastomosis was 0.70 -2.16 m/s with a mean of (1.31 ±0.40) m/s. No pulmonary stenosis was found with the simplified Bernoulli formula. There was no significant difference regarding the pulmonary diameter and the pulmonary artery flow velocity as compared with the normal children of the same age. Conclusion The fresh autologuos pericardium is reliable for reconstruction of new pulmonary arterial root in ASO.

Objective To discuss the efficacy of retroperitoneal laparoscopic dismembered pyeloplasty for pediatric ureteropelvic junction obstruction(UPJO). Methods Retroperitoneal laparoscopic dismembered pyeloplasty was performed on 24 patients with UPJO.The age of the patients ranged from 3 to 14 years(mean,7 years).The diagnosis was set up by ultrasonography,IVU,CT or magnetic resonance urography.All the patients had hydronephrosis,with 4 cases mild,10 cases moderate and 10 severe ones. Results All operations were completed laparoscopieally,without conversions to open surgery during operation.The mean operative time was 180 min(range 150 to 200).The mean blood loss was 60 ml(range 40 to 100)and the mean postoperative hospital stay was 7 d (range 5 to 9).All 24 patients were followed-up for 6 to 24 months(mean,1 4 months).There was no stricture at UPJ.Eighteen patients had complete resolution of hydronephrosis and 6 patients showed obvious alleviation in hydronephrosis. Conclusion Retroperitoneal laparoseopie dismembered pyeloplasty could be a mini-invasive,safe,and effective procedure for the treatment of UPJO in pediatric patients.

Objective To investigate the safty and feasibility of simultaneous minimally invasive technique for congenital heart disease (CHD) and pectus excavatum (PE).Methods From July 2006 to June 2011,6 children with PE associated with CHD were treated by simultaneous minimally invasive technique.They were 4 boys and 2 girls,aged from 4 years to 6 years 5 months ( average 5 years and 4 month),.The body weight were from 16 kg to 20 kg [ average ( 18.00 ± 1.79kg ].CT Hailer index were 3.9 - 5.0 ( average 4.35 ± 0.43 ).4 patients with ventricular septal defect (VSD) were treated by minimally invasive closure device,including 3 membranous VSD and 1 subaortic VSD.The defect diameter was 4 - 5 mm.2 cases with atrial septal defect (ASD) were treated using the same technique.the diameter of ASD was 12 - 16 mm.After minimally invasive heart surgery,Nuss operation was carried out in all 6 patients for their PE.Results All operations were successful and patients were extubated 5 - 11 h after operation [ mean ( 8.17 ± 2.04) h ].The pericardial mediastinal drainage was removed at 48 h postoperatively.There were no operative mortality and severe postoperative complications.1 patient had delayed wound healing and was successfully discharged.The plate was removed in 3 cases,and they all had satisfactory outcomes.Conclusion Simultaneous minimally invasive technique is a safe and effeictive mothod for treating pectus excavatum and congenital heart disease.

Objective To investigate the effect of the side of cerebral lesion on the outcome in patients with ischemic stroke.Methods A total of 407 consecutive anterior circulation ischemic stroke patients within 14 days after symptom onset were recruited prospectively.The basic data ofthe e,~ISes were collected,such as the National Institutes ofHealth Stroke Scale (NU-ISS)and the side ofcerebral lesion.The modified Rankin Scale(mRS)was used to evaluate the prognosis of the patients at 6 raomhs.Results Of the 407 patients recruited,230 patients (56.5%)Were left hemisphere stroke,177(43.5%)were fight hemisphere stroke.After multivariable logistic recession analysis,the age(odds ratio[OR]1.022,95% confidence interval[CI]1.001-1.043,P=0.040),the side of lesion(OR 1.999.95%CI1.179.3.389.P=0.010),the time from onset to admission(OR1.006,95%(7/1.002-1.010,P=0.007),the outcome of the anterior circulation ischcmic stroke at 6 months aftel"onset.The outcome of the right hemisphere stroke Was significantly worse than that of the left hemisphere stroke.The onset-admission time in patients with right hemisphere stroke(median 12 h,median 39.61 h)was significantly delayed compared to the patients with left hemisphere stroke(median 12 h,median 22.72 h;Z=-2.962,P=0.003).Condusions The outcome of the left hemisphere stroke at 6 months after onset is superior to the right hemisphere stroke,and it mau be associated with the delayed admission.

Objective To evaluate the effects of electromagnetic irradiation of 2000 μW/cm2 exposure on mRNA and protein expression levels of immunoreactive protein and mRNA of NMDAR1 in rats hippocampal,and to explore the impaired mechanism of electromagnetic irradiation on learning and memory.Methods Rats were randomly divided into normal control group, sham-radiated group, and 1 h/d, 2 h/d, and 3 h/d radiation groups.The rats in the radiation groups were fixed and recieved microwave exposure of 2000 μW/cm2, then their learning and memory abilities were tested by Morris water maze experiment, the change of NR1 protein in hippocampal neurons of each group of rats was measured with immunohistochmistry and western blot techniques, and the expression of NR1 mRNA in hippocampus was determined by RT-PCR.Results In the water maze test,compared with the normal control group (8.8 ± 1.66 ), the escape latency of three radiated groups rats ( 1 h/d ( 12.29 ±1.36) s,2 h/d ( 17.99 ±2.25) s,and 3 h/d (24.66 ±5.56) s) were significantly longer (P＜0.05).In the radiation group,the hippocampal neurons of rats showed evident reduction in the ratio of NR1 positive cells,irregular,and arrayed in disorder.Moreover,compared with the normal control group ( (0.70 ±0.11 ), (0.68 ±0.11 ) ) ,the expession of NR1 protein ( 1 h/d (0.122 ±0.026) ,2 h/d (0.102 ±0.023) ,and 3 h/d (0.060 ± 0.009) ) and its mRNA ( 1 h/d (0.46 ±0.07) ,2 h/d (0.35 ±0.05) ,and 3 h/d (0.12 ±0.02) ) in hippocampal neurons was significantly decreased (P＜0.05).Among the indicators, there was no significant difference between sham-radiated group and normal control group.Conclusions Electromagnetic irradiation of 2000 μW/cm2 exposure can impair the learning and memory abilities of rats possibly through a mechanism correlated with the lower expression of NR1 protein and its mRNA in hippocampus.