Constructivism teaching theory emphasizes the central role of student in learning and this theoretical framework holds that learning always builds upon the active exploring and discovering new knowledge.Department of orthopedics in the first affiliated hospital of Chongqing Medical University introduced and implemented constructivism teaching in teachers' research and teaching activity as well as in students' learning.This mobilized students' learning enthusiasm and improved clinical teaching quality.

A description of the concept,origin and development,and key contents of the system safety theory,and an analysis of the presence and future of China's medical safety management,holding that such a theory enjoys a promising perspective in medical safety managemenL Medical safety management needs to follow such a theory as fl guideline,and its principles to set system safety objectives,and to determine the scope of the safety system_By building a comprehensive feedback mechanism,clarifying the responsibility borders and advocating a safety culture,medical safety management can be significantly upgraded.

Objective To investigate the mechanism of radiosensitization by cetuximab (C225) on human tongue cancer Tca8113 cell line in vitro.Methods Tca8113 cell line with and without C225 treatment received 6 MV X-ray irradiation of different doses (0, 2,4,6, 8 and 10 Gy). Cell proliferation,cell-cycle distribution and clonogenic survival were analyzed through cell counting,MTT,colony formation assay,and flow cytometry,respectively.Results After irradiation of different doses,the growth inhibition rates in C225 group were higher than control (t =- 15.6 - -3.0,P＜0.05),the radiobiological parameters (D0,Dq,N,and SF2 ) in C225 group were lower than control so that SER of C225 group was 1.353,and the proportions of G0/G1 cells in C225 group were higher than control ( t =-7.64,-7.89,-4.78,P ＜0.05 ) at 4,6,8 Gy.When the irradiation doses increased,the early phase apoptosis in both groups increased at first and then decreased with the maximum difference at 4 Gy [(7.96±0.36)％ in C225 group and (4.13 ±0.29)％ in control group,t =-12.75,P＜0.01 ].Conclusions C225 has radiosensitization effect on Tca8113 cell line,possible through Go/G1 arrest and induction of apoptosia.

Objective To evaluate the efficacy of radiosynovectomy with 32P colloid in haemophilic synovitis of adolescents. MethodsRadiosynovectomy with 32P colloid was primary performed on 26 male haemophilic patients(26 joints),whose average age was 16 years(11 to 21 years).The average dose of 32P colloid was 2.1 mCi(1.0 to 3.0 mCi). Results After 6-month interval,haemarthrosis was reduced by no less than 30% in 23 patients,with a total efficacy of 88.5%.The mean frequency of haemarthrosis was reduced from 1.9 per month of presynovectomy to 0.3 per month of postsynovectomy(P

Objective To discuss the surgical indications,relative merits and clinical outcomes of anterior reconstruction plate fixation for treating unstable posterior pelvic ring injuries.MethodsA retrospective study was done on clinical data of 36 patients with unstable posterior pelvic ring injuries treated with anterior reconstruction plate fixation from August 2004 to July 2010 and followed up for minimum one year.There were 25 males and 11 females,at mean age of 35.8 years ( range,13-62 years).There were two patients with anterior dislocation of the sacroiliac joint and 34 with posterior dislocation.According to Tile classification,there were four patients with type B fractures ( B1:3,B2:1 ) and 32 with type C fractures (C1-1:17,C1-2:12,C2:2,C3:1 ).Results All patients were followed up for average 2.3 years ( range,1-6 years).Fat liquefaction and superficial infection were founded in two patients who were cured by dressing change and frequent but low-dose blood transfusion.Eight patients were subjected to iatrogenic lateral femoral cutaneous nerve injury.Meanwhile,five of them was recovered after treatment with neurotrophic drugs,but there were still three patients leaving lateral thigh numbness.One patient had L5 nerve root injury due to pull force,and was recovered after three months of neurotrophic drug therapy.According to Matta and Tometta criteria,the reduction results were excellent in 23 patients,good in 11 and fair in four,with excellence rate of 94％.No reduction loss or implant failure occurred.According to Majeed scoring system,the clinical outcomes were excellent in 17 patients,good in 14,fair in four and poor in one,with excellence rate of 86％.Of the seven patients pre-operatively associated with sacral plexusinjury,three obtained full recovery,two got partial recovery and two were free from recovery.Conclusion The anterior reconstruction plate fixation takes advantages of wide surgical indications,simple exposure,low infection rate,satisfactory reduction and solid fixation and may be a main treatment method for unstable posterior pelvic ring injuries.

AIMTo search for flavonoids which possess stronger vasorelaxation action.

METHODSFour quercetin glycosides (1a - d) were synthesized from quercetin in three steps i. e. selective protection of quercetin, condensation with corresponding acetyiglycosyl bromide, and then removal of the protecting group; Six flavone compounds (2a - f) were prepared from phloroglucinol according to the conventional methods; The structures of synthetic compounds were confirmed by IR, 1H NMR, 13C NMR and MS. Vasorelaxation action of ten synthetic quercetin derivatives (or analogues) and four natural flavonoids compounds were examined on the isolated rat thoracic aorta rings; Comparative octanol-water partition coefficients (logP) were measured using a reversed-phase HPLC method.

RESULTSMost of the tested flavonoids showed concentration dependent relaxation effects against PE-induced contractions of rat aortic rings. These compounds had stronger action with the augment of logP values.

CONCLUSIONCompound 3-bromo-5 ,7-dihydroxyflavone (2d) was identified to have the most potent vasodilating action. These compounds exert vasodilating effects that are related to the logP values. A structure-activity relationship of flavonoids was suggested.

Animals ; Aorta, Thoracic ; drug effects ; Dose-Response Relationship, Drug ; Flavonoids ; chemical synthesis ; chemistry ; pharmacology ; Male ; Molecular Conformation ; Molecular Structure ; Quercetin ; administration & dosage ; analogs & derivatives ; chemical synthesis ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Structure-Activity Relationship ; Vasodilation ; drug effects ; Vasodilator Agents ; administration & dosage ; chemical synthesis ; pharmacology

Virtual slides were applied in experiment teaching of pathology on trial in clinic medicine college of Sichuan university.The resuhs from the Survey showed that students and teachers preferred virtual slides in learning microscopic lesions.Virtual Slides can help us save time,promote quality of observation,carry out discussion based teaching and manage teaching documents.It can be used in network teaching after marking the lesions.

Objective To evaluate the effects of femoral offset (FO) on the stress level of bone cement total hip arthroplasty (THA) in the elder patients by the three-dimensional finite element analysis. Methods The normal bilateral hip joints in two cases was determined with CT imaging,with parameters including FO,neck shaft angle and neck length.The three-dimensional finite element model of THA was built so as to make Von Mises stress analysis of the changes of different neck lengths,neck shaft angles and FO. Results Stress levels in the prosthesis and bone cement reduced monotonically with the increase of neck shaft angles.In the meantime,the stress levels were lowered when neck length was in a range of 35-44 mm,but beyond the range they showed monotonous increase. Conclusions The reduction of stress levels of prosthesis and bone cement,promotion of femur stress and extension of range of motion of hip joints are closely related to FO.FO reconstruction benefits the restoration of abductor force arm and biomechanical function of normal hip joints.

Objective To investigate the inhibition effect of continuous low dose rate radiation by 125Ⅰ radioactive seeds on Hep-2 cells and the corresponding mechanisms.Methods Hep-2 cells were divided into three groups,control group,single dose radiation group with high dose rate form X-rays (SDR) and continuous low dose rate radiation by 125Ⅰ seeds group (125Ⅰ-CLDR).After exposure to SDR and 125Ⅰ-CLDR,colony formation assay was used to determine the radiosensitivity and RBE,trypan blue exclusion assay was used to determine cell proliferation,and flow cytometry was used to detect cell apoptosis and cell cycle arrest.Results The radiosensitivity of Hep-2 cells to 125Ⅰ-CLDR was higher than that to SDR.The RBE of 125Ⅰ-CLDR versus SDR was approximately 1.61.The α/β ratio of 125Ⅰ-CLDR group was higher than that of SDR group.Both SDR and 125Ⅰ-CLDR inhibited cell proliferation (t =30.9,40.7,P＜0.05),in which 125Ⅰ-CLDR was stronger than SDR (t =9.8,P＜0.05).In addition,the incidences of apoptosis and G2/M arrest induced by125Ⅰ-CLDR were also stronger than those induced by SDR (t =5.8,19.8,P ＜ 0.05).Conclusions 125Ⅰ-CLDR generates more serious inhibition effects than SDR on reducing cellular DNA repair capacity,inducing cell apoptosis and G2/M arrest and inhibiting proliferation of Hep-2 cells.

Objective:To analysis the appearances and to evaluate the diagnostic value of X-ray CT and MR imaging in osteoid osteoma.Methods:22 cases 19 females and 3 males of osteoid osteoma proved by surgical pathology and their X-ray,CT and MRI were reviewed.The ability of X-ray,CT and MRI to demonstrate the nidus and surrounding reaction were analyzed.Results:The nidus were appeared as round or oval shape and the diameter was less than 2 cm.It was fomd in 17 cases of X-ray film，22 CT and 20 of MRI .There were different degree of bone sclerosis,periosteal reaction and soft tissues or bone marrow edema around the nidus.The diagnostic accuracy was 77.3% for X-ray，100% for CT and 90.9% for MRI.Conclusion:Most of osteoid osteoma have the typical appearances and is no difficult to make diagnosis.CT scan is the most accuracy method to demonstrate the nidus.It is possible to make misdiagnosis only with X-ray or MRI for the case that the hidus not be demonstodted.