Objective To evaluate the differences in image quality and radiation dose in the neck CTA between low tube voltage scanning method combined with exact calculation of contrast dosage and conventional scanning methods.Methods Ninety patients who had undergone neck CTA examination from October 2012 to June 2013 were prospectively selected to perform study.Patients were randomly divided into Group A,B and C,each with 30 cases.Tube voltage and contrast amount were,respectively,120 kV and 70-80 ml for Group A (conventional group),100 kV and exact calculation for Group B,80 kV and exact calculation for Group C.Using ANOVA test,radiation dose,contrast amount,CNR were statistically analyzed among three groups.Subjective evaluations were made of image quality by two experienced radiologists based on a 5-point system.Results The effective doses in Group B and C were (4.5 ± 0.7) mSv and (2.1 ± 0.4) mSv,respectively,significantly lower than (6.6 ± 0.9) mSv in Group A,with statistically significant difference(F =72.4,P ＜ 0.05).The amounts of contrast were significantly lower in Group B and C than that in Group A,which respectively were (73.2 ± 8.2) ml for Group A and (48.2 ± 5.1) for Group B and (48.6 ± 5.4) ml for Group C,with statistically significant difference (F =56.8,P ＜ 0.05).CNRs increased respectively by 42.2％ in Group B and by 42.2％ in Group C compared with Group A,with statistically significant difference (F =72.6,P ＜ 0.05).Venous artifact images were found in 10 patients of Group A,having different effects on image quality,whereas in Group B and C,there were not vein artifacts to found.Conclusions The low tube voltage (80 kV) scanning method combined with exact calculation of contrast features not only significantly lower radiation dose and lower contrast amount used,but also improved image quality in comparison with conventional method.

Objective To probe the feasibility of gemstone spectral CT in imaging pulmonary angiography with low dose contrast medium.Methods A prospective study with multi-slice spiral CT pulmonary angiography was performed in consecutive 48 patients suspected with pulmonary embolism.Two groups (n=24 respectively)were divided at random including Group A used Gemstone spectral CT with 35 mL of contrast medium and Group B using 64-slice CT with conventional 80~90 mL of contrast medium.The CT values of the pulmonary trunk,lobe artery,pulmonary vein and ascending aorta were measured.The contrast to noise ratio of the pulmonary artery was also calculated.In addition,the image quality of CTA was evaluated independently by two experienced ra-diologists.Results The CT values of the pulmonary trunk and the subsegmental branches,and the CNR in Group A were signifi-cantly higher than those in group B,exhibiting statistical differences (t=8.6,P <0.001;t=12.2,P <0.001;t=1 1.3,P <0.001 respectively).However,the CT value of aorta in Group A was significantly lower than that in Group B (t=-7.6,P <0.001).The evaluation results of the CTA images by two radiologists showed that the image quality in Group A was better than that in Group B (Z =-8.6,P <0.001;Z =-9.0,P <0.001 ).Conclusion The image quality of pulmonary angiography with gemstone spectral CT using low contrast medium dose can be improved compared with the conventional spiral CT.

Objective To study the changes of insulin-like growth factor-1(IGF-1) in serum of patients with obstructive jaundice.Methods The clinical data of 20 patients with obstructive jaundice were collected and the measurement of serum TNF-?,ALT, ALP, endotoxin and IGF-1 were performed. Results The serum IGF-1 in obstructive jaundice was significantly lower than that in gallbladder stone(P

ObjectiveTo evaluate the effectiveness of PBL teaching model for medical students in surgery bed side teaching.MethodsThe method of meta-analysis.ResultsFinally,twenty-six documents met the requirement.The resuhs of Meta-analysis showed that,in the aspect of theory improvement for medical students,WMD=6.46,95 ％ CI 为 2.56 ～ 10.36,P＜0.01 ; in the aspect of skill ability improvement,WMD=5.32,95 ％ CI 为 2.47 ～ 8.16,P ＜0.01.ConclusionThe model of PBL teaching could significantly improve the effectiveness in theoretical knowledge and skill ability.

Objective To systematically review the efficacy and safety of drug-eluting stent(DES) versus coronary artery bypass grafting(CABG) in the treatment of left anterior descending coronary artery(CAD) stenosis.Methods Literature about the efficacy and safety of DES versus CABG for LAD stenosis was retrieved from digital databases of MEDLINE, EMbase, PubMed, and the Cochrane Library by November 2016.Data extraction and quality assessment of included studies were conducted by two independent reviewers.RevMan 5.3 software was used to perform meta-analysis.Results Ten studies involving 9771 patients were finally included.The results of meta-analysis showed that there was no significant difference in mortality [RR=0.88,95%CI(0.70,1.11),P=0.28],major adverse cardiovascular events[MACE,RR=1.04,95%CI(0.88,1.24),P=0.63] or myocardial infarction [MI,RR=0.92,95%CI(0.56,1.53),P=0.75], but PCI-DES significantly increased the risk of TVR [OR=2.43,95%CI(1.61,3.69),P<0.0001].Conclusion For LAD stenosis, PCI-DES strategy causes as high a rate of mortality, MACE and MI as CABG or DES, but PCI-DES can significantly increase the risk of TVR, so we should be cautious clinically.

Objective To evaluate the feasibility of a low-dose contrast medium protocol for 64-slice CT angiography (CTA) of head using a low-tube-voltage setting.Methods ① Phantom study:64-slice spiral CT respectively sets 80,100,120,140 kV and 100,200,300,400,500 and 600 mA as scanning parameter lines.Analysis of the best Signal-to-noise ratios (SNR) and contrast to noise ratios (CNR).②Clinical study:to prospectively continuous select sixty-six patients with suspected intracranial aneurysm and arteriovenous malformation and so on from April to October of 2012 to perform hand CTA inspection.The random number table method for A,B two groups,33 patients in each group.Group A (conventional group)scanning parameters:120 kV,400 mA and amount of contrast agent:1 ml/kg; Group B(test group) scanning parameters:80 kV,600 mA,amount of contrast agent 0.5 ml/kg.Using independent samples t test for each group radiation dose,SNR,CNR were statistically analyzed.By two experienced radiologists to 5 points on two groups of image quality subjective evaluation.Mann-Whitney U test was used for statistical analysis of subjective evaluation.Results Group A and B group CTDIvol respectively is 59.1,27.5 mGy.Group B than in group A,CTDIvol decreased by 53.5％.A,B groups of the SNR,CNR were 71.5 ± 10.7,92.0 ± 7.4; 58.5 ± 10.5,79.6 ± 7.7,Group B than in group A SNR,CNR were enhanced by 22.3％,26.4％,differences were statistics significance (t =584.0,388.6,P ＜ 0.01).The subjective image evaluation of group B was bigher than group A (Z =31.2,23.4,P ＜ 0.05),differences were statistics significance.Two physicians on CTA images to assess the consistency of uniform height(Kappa =0.904,P ＜0.05).Conclusion In the head CTA examination,use of low tube voltage combined with low contrast dose not only can improve the image quality but also radiation dose were significantly lower.

Objective To analyze the factors that influence joint function after plate fixation of unstable pelvic fractures.Methods A retrospective study was conducted to analyze the 109 patients with unstable pelvic fracture who had been treated with plate fixation from January 2007 to September 2014.They were 69 men and 40 women,23 to 72 years of age (average,46.3 years).By the Tile classification,15 cases were type B1,37 type B2,14 type B3,19 type C1,16 type C2,and 8 type C3.Their postoperative joint function was evaluated according to the Majeed criteria for functional evaluation.There were 86 cases in the good-to-excellent group (78.9％) and 23 in the fair-to-poor group (21.1％).Their data were analyzed in terms of gender,age,preoperative injury severity scale (ISS),body mass index (BMI),operation time,fracture type,reduction quality,postoperative complications,bone density,and postoperative weight bearing time.The influential factors were determined using Logistic regression analysis.Results All the 109 patients obtained a mean follow-up of 18.7 months (from 12 to 53 months).Preoperative ISS (P =0.000),fracture type (P =0.008),reduction quality (P =0.009) and postoperative complications (P =0.000) were identified as the factors influencing joint function after plate fixation of unstable pelvic fractures.Conclusion Preoperative assessment by ISS,a clear understanding of the pelvic fracture type,anatomical reduction of the fracture and efforts to reduce postoperative complications can effectively improve functional recovery of the joint after plate fixation of unstable pelvic fractures.

Objective To compare the diagnostic efficacy of bone scintigraphy and MRI on vertebral metastases in patients with nasopharyngeal cancer (NPC). Methods Forty-seven patients of NPC and clinically confirmed metastatic disease in spine underwent bone scintigraphy and MR examination. The number of involved vertebri diagnosed with two methods were calculated and compared retrospectively. Results A total of 187 vertebral metastases were found in 47 patients, among which 153 (81.82%) were detected with bone scintigarphy and 182 (97.33%) were diagnosed with MRI (χ~2＝23.758, P＝0.000). Conclusion Compared with bone scintigraphy, MRI is superior in detecting vertebral metastases from NPC, and can be used as the first choice for the early diagnosis of spinal metastases from NPC.

Objective To investigate the diagnostic accuracy of 13C urea breath test (13C-UBT)in the diagnosis of Helicobacter pylori (Hp) infection in patients with gastric remnant.Methods A total of 94 gastric remnant patients (gastric remnant group) and 100 non-gastric remnant patients (control group) received 13C-UBT.According to the course of the disease,the gastric remnant group were divided into group 1 (29 cases,≤5 years),group 2 (33 cases,6 to 10 years) and group 3 (32cases,＞10 years).Before surgery,the diagnosis of Hp infection was according to 13C-UBT and gastric mucosa tissue staining.After surgery,the diagnosis was according to gastric mucosa tissue staining.The applying value of 13C-UBT in gastric remnant patients was evaluated.The consistency of results between 13C-UBT and gastric mucosa tissue staining were evaluated by the Kappa test.Results In gastric remnant group,the Hp infection rate after surgery (37.2％) was obviously lower than that before operation (79.8％;x2 =35.058,P＜0.01) and that of control group (77.0％).After surgery,the Hp infection rate of patients with Billroth Ⅱ gastrectomy (24.4％) was lower than that of patients with Billroth Ⅰ gastrectomy (47.2％ ; x2 =5.133,P=0.023).Before surgery,the Hp infection rate of gastric remnant subgroups were similar (P＞0.05).With the extension of the postoperative course,the Hp infection rate gradually decreased in gastric remnant subgroups (group 1:58.6％,group 2:36.4％,group 3:18.8％; x2=7.839,P=0.021).Setting the cut-off point at 2.0‰ in the gastric remnant group and 3.5‰ in the control group,the accuracy rate of diagnosis was the highest (92.6％ and 96.0％).There was good consistency between the results of 13C-UBT and gastric mucosa tissue staining (Kappa =0.84,P＜0.01).Conclusion With suitable operation and standard,13C-UBT may be a easy,safe and effective assay applied in the gastric remnant patients.

Objective To investigate the role of renin angiotensin system (RAS) in pathogenesis of nonalcoholic fatty liver disease (NAFLD).Methods Twenty-four Wistar rats were evenly divided into control group and model group.The rats of control group were fed with normal diet,and model group were with high-fat diet.Rats were killed at the eighth week and serum liver function,blood lipid,glucose and insulin were tested.The liver tissues were stained with HE and Picro acid-Sirius red for pathological observation.The liver tissue concentration of angiotensin Ⅱ was determined by ELISA method and the expression of TGF-β1 in liver tissue was examined by immunohistochemistry.Results After eight weeks high fat feeding,weight,liver index,liver function,blood lipids and serum insulin of model group were significantly higher than those of control group (weight:(463.50±22.72) g vs.(404.29±10.32) g; liver index:(3.75±0.21) g vs.(2.66±0.15) g; ALT:(79.8±8.6) U/L vs.(58.8±11.6) U/L; AST:(200.01±51.72) U/L vs.(150.30±37.27) U/L; total cholesterol:(3.67±0.48) mmol/L vs.(1.50±0.23) mmol/L; triglycerides:(2.06±0.40) mmol/L vs.(0.71±0.34) mmol/L; insulin:(17.37±2.89) pmol/L vs.(11.08±2.12) pmol/L),and all the differences were statistically significant (P＜0.01).The histopathological results of model group indicated liver steatosis,inflammatory reaction in part of lobule and portal area and significant fibrosis in part of liver tissue.The liver tissue angiotonin Ⅱ concentration of model group [(32.80 ± 2.81)pg/ml] was higher than that of control group [(22.83 ± 1.75) pg/ml,t =9.559,P＜0.01].The immunohistochemistry results showed that the expression of TGF-β1 of model group was obviously higher than that of control group (Z=-2.540,P =0.011 ).Spearman correlation analysis revealed that the increasing degree of angiotensin Ⅱ concentration was positively correlated with liver steatosis scores (r=0.644,P=0.002) and the expression of TGF-β1 (r=0.470,P=0.037).Conclusion The concentration of angiotensin Ⅱ and TGF-β1 increased in the livers of model rats,which indicated that RAS may participate in the pathogenesis and progress of NAFLD.