Purpoes: To discuss the MRI manifestation and classification of discoid lateral meniscus and improve the accuracy of MRI diagnosis for discoid meniscus.Materials and Methods: 70 cases of discoid meniscus verified by arthroscopy were divided into impuberal group(n=30) and adult group (n =40).Following three quantitative parameters were measured.The meniscal width and tibial plateau width on the coronal slice showing the inttercondyloid spine( a),the number of the spine showing butterfly change when the layer thickness was 4mm(b) and the maximum width showing butterfly change on the sagittal slice(c).The discoid meniscus were classified as slab type (n=33),wedge type(n = 19),hypertrophied - horn type(n= 18) according to their shape.Results:69 cases had torn in different extent,a>or =20% (P<0.01) in all of cases.No significant difference in the incidence of each type existed between two groups(P>0.05).Significant difference in the incidence of each type existed in c(P<0.05).Conclusions: a >or = 20% is the most reliable criterion to diagnose discoid meniscus.Using b as the criterion of discoid meniscus is easy to occur missed diagnosis,c in the wedge type is bigger than the one in the hypertrophied type.Age can impact the classification of discoid meniscus.

Objective To explore the prevalence of multilevel lumbar spondylolysis in operation patients,and to evaluate the diagnostic value of CT reconstruction on multilevel lumbar spondylolysis.Methods A total of 312 patients,who had undergone surgical treatment in our hospital from January 2004 to March 2012 for lumbar spondylolysis,were enrolled in this study.There were 147 males (47％) and 165 females (53％),aged from 12 to 76 years (average,44 years).Every patient underwent lumbar spine X-ray examination including anteroposterior,lateral,over-flexion,over-extension and double oblique X-rays,as well as CT examination.The prevalence of multilevel lumbar spondylolysis in all operation patients and the involved segments were recorded and analyzed.Moreover,the clinical manifestation and radiological features were summarized.Results In all enrolled patients,there were 9 patients (2.9％) with multilevel lumbar spondylolysis,including 5 males and 4 females,aged from 21 to 51 years (average,39 years).As for lesion distribution,there were 8 cases of bilateral spondylolysis located at both L4 and L5,and 1 case of bilateral spondylolysis at L5 combined with right spondylolysis of L4 and discontinuity in the base of left pedicle of L4.Among 9 patients,only 3 patients obtained correct diagnosis by anteroposterior and double oblique X-rays of the lumbar spine,while all patients got final diagnosis by sagittal and oblique coronal reconstruction of lumbar spine CT scan.The oblique coronal CT reconstruction could show the details of bone defect in lumbar vertebral isthmus,bony callus,peripheral osteophytes,as well as fibroplasia.For unilateral lumbar spondylolysis,the oblique coronal CT reconstruction could also show the reactive sclerosis in contralateral lamina of vertebra.Conclusion Multilevel lumbar spondylolysis is not rare in operation patients,and L4 and L5 are most common involved levels.Sagittal and oblique coronal reconstruction of lumbar spine CT scan is more accurate in showing the details of lumbar spondylolysis,which is helpful in decreasing the missed diagnosis and improving therapy.

Objective To study the difference of Han male children and adolescent bone age of wrist-hand in Beijing and Guangzhou.Methods Bone age (BA) of left hand-wrist was assessed using X-ray by two radiologists based on CHN atlas method in 993 healthy children and adolescents (age range:1.0-19.0 years).The radiologists were blinded to the chronological age (CA) of those children.The interobserver variations were analyzed for evaluating the reliability of CHN Atlas method.The difference between CA and BA were separately assessed,and were analyzed by t test.Results Close correlation was found between BA and CA (r =0.969,0.957,P ＜ 0.01) in both two regions.The bone age was advanced at 1.0-3.9,and 7.0-15.9 years in Beijing boys,and at 1.0-2.9,6.0-7.9 years in Guangzhou bpys.There was significant difference at 1.0-1.9,9.0-14.9 years between Beijing and Guangzhou.Conclusions The bone age of Han male children adolescent in Beijing and Guangzhou area has the characteristic of acceleration.There is significance difference at some years between Beijing and Guangzhou,and the results can provide potential value for the further study of BA and clinical medicine.

Objective To construct prokaryotic expression vector of NS5A transactivating protein 7 of hepatitis C virus (NS5ATP7), induce the expression of NS5ATP7 in E. coli, and to predict its structure and function by bioinformatics analysis. Methods NS5ATP7 gene was amplified by reverse transcription PCR (RT-PCR) using HepG2 cells mRNA as template, and was ligated into pGEM-T cloning vector. After verifying the sequence of the inserted fragment by restriction enzyme digestion identification and sequencing, NS5ATP7 was cloned into inducible prokaryotic expression vector pET-32a(+) and transfected into competent E. coli BL21. The protein expression was induced with IPTG and the product was analyzed by SDS-PAGE and Western blotting hybridization. The structure and function of NS5ATP7 were predicted using bioinformatics techniques. Results NS5ATP7 gene with about 891bp was amplified by RT-PCR, which was coincident with that we expected, and it was then inserted into expression vector pET-32a(+). Under the induction of IPTG, the recombinant NS5ATP7 was expressed successfully. SDS-PAGE and Western blotting assay showed that this recombinant protein possessed good immunogenicity. Bioinformatics method such as ExPASy, TMHMM and SignalP analysis indicated that NS5ATP7 was full of helices, had neither transmembranous structure nor signal peptide. Conclusions The recombinant NS5ATP7 gene could be successfully expressed in prokaryotic expression system of E. coli, which might lay the foundation of studying the immunogenicity and biological charactersitics of the NS5ATP7. Bioinformatics analysis may provide a new method to analyze the structure and function of a new protein.

Objective: To evaluate the effect of concomitant chemoradiotherapy for the prevention of recurrence and metastasis of postoperative salivary adenoid cystic carcinoma(SACC).Methods: 14 cases of salivary adenoid cystic carcinoma after operation were treated with concomitant chemoradiotherapy. Regular radiotherapy of 60 Gy and chemotherapy with hydroxycamptothecin (HCPT) at 10 mg/m 2 , 3 times a week, were administered. HCPT was given in 1st, 2nd, 4th and 5th week. Recurrence and metastasis of SACC after operation were observed using CT, MRI, ultrasonography and X ray. Results: After 3～17 months' follow up, relapse free survival was 100%. No recurrence and metastasis of SACC after operation were found. Adverse reactions of the chemotherapy were nausea, vomiting and leukopenia. After suspended in a short time and using ondansetron and /or G CSF the chemotherapy of HCPT was continued and completed. Conclusion: concomitant chemoradiotherapy of HCPT and radiotherapy can prevent recurrence and metastasis of SACC after operation. The efficacy of long term needs further observation.

Objective:To investigate the feasibility of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI)parameters in differentiating musculoskeletal tumors with different behaviours of pathological findings before therapy.Methods:A total of 34 subjects of musculoskeletal tumors were in-volved in this retrospective analysis.DCE-MRI was performed using a fat-saturated 3 D VIBE (volumetric interpolated breath-hold exam)imaging sequence with following parameters:FA,10 degree;TR/TE, 5.6/2.4 ms;slice thickness,4.0 mm with no intersection gap;field of view,310 mm ×213 mm;ma-trix,256 ×178;voxel size,1 .2 mm ×1 .2 mm ×4.0 mm;parallel imaging acceleration factor.The ac-tuation time for the DCE-MRI sequence was 255 s with a temporal resolution of 5 s and 40 image vo-lumes.Using pathological results as a gold standard,tumors were divided into benign,borderline and malignant tumors.Toft’s model was used for calculation of Ktrans (volume transfer constant),Ve (extra-vascular extracellular space distribute volume per unit tissue volume)and Kep(microvascular permeability reflux constant).Those parameters were compared between the lesions and the control tissues using paired t-tests.The one-way analysis of variance was used to assess the difference among benign,border-line and malignant tumors.P values <0.05 difference was statistically significant.Results:Based on the WHO Classification of Tumours of Soft Tissue and Bone(2012)criteria,34 patients were divided into three groups:1 1 for benign tumors,12 for borderline tumors,and 1 1 for malignancies.Compared with control tissues,Ktrans and Kepshowed no difference,but Ve was increased in benign tumors,Kep showed no diffe-rence,butKtransandVewereincreasedinborderlinetumors, Ktrans,KepandVewereincreasedin malignant tumors.Ktrans(P<0.001 )and Kep (P<0.01 )were significantly higher in malignant tumors than in benign and borderline tumors,but did not show any difference between benign tumors and border-line tumors.Ve was significantly higher in malignant tumors than in benign (P<0.05),but did not show any difference between malignant and borderline tumors,benign tumors and borderline tumors (P >0.05 ).Conclusion:DCE-MRI technique is useful to evaluate the pathological behaviour of musculoske-letal tumors.The quantitative analysis of DCE parameters in conjunction with conventional MR images can improve the accuracy of musculoskeletal tumor qualitative analysis.

Objective To evaluate the MR imaging features of chondrnblastoma. Methods MRI examinations of 20 patients with histological proven chondroblastoma were reviewed retrospectively. The MRI findings of chondroblastoma including the signal intensity, the shape, the growth patterns, and the surrounding bone marrow edema and the adjacent soft tissue edema, the periosteal reaction, the adjacent joint effusion were analyzed . Results All 20 cases demonstrated heterogeneous MR signal intensity on T1WI and T2WI images and showed Iobular margins. Sixteen cases demonstrated expansive growth patterns. Surrounding bone marrow edema was found in 18 cases and adjacent soft tissue edema in 14 cases. Periosteal reaction was identified in 6 cases. In 7 cases the tumor extended to adjacent soft tissue. Adjacent joint effusion was visible on MRI in 6 cases. Conclusion Heterogeneous signal intensity, lobular margins and expansive growth pattern, adjacent bone marrow and soft tissue edema were the common features of chondroblastoma on MRI.

Objective: To investigate the effect of open-mouth jaw plate in the treatment of condylar fracture in children. Method: Open-mouth plates in the height of 2～3 cm were respectively made in op e n-mouth position for 12 children aged 3～6 years old with condylar fractures an d used by the children with the help of doctors or parents for 3～6 months.Follo w -up was carried out by clinical observation and X-ray radiograph.Re sults: Satisfactory results were obtained in all the patients examine d by clinical observation and X-ray radiograph. Conclusion: The method of open-mouth plate is effective in the treatment of condylar f racture in children.

Objective:To evaluate the precision of quantitative CT (QCT) in measuring fat content of goose liver and to explore the influence of tube voltage on liver fat measurement.Methods:From January to March 2017, 22 Landes geese were selected to establish fatty liver models with overfeeding. The QCT was performed under 2 different tube voltages, 80 and 120 kV. In addition to the voltage, the other scanning parameters were the same. Three ROI were placed in the centre part of the left lobe, upper and lower half of the right lobe on the 3D reconstructed images. The volume percentage of goose liver fat (Fat% QCT) was calculated according to the formula provided by Mindways. Immediately after the QCT examinations, each goose was dissected, and the whole liver was removed. Then samples were taken in the corresponding areas of the ROI by QCT. The fat (triglyceride) content of the samples was measured by the biochemical extraction method. The Spearman correlation tests were used to determine the correlation between the QCT measurements of 80 kV and 120 kV groups and the results of biochemical extraction method. The Wilcoxon signed-rank test was performed to compare Fat% QCT between 80 kV and 120 kV groups. Bland-Altman plots were used to assess agreement between the two groups′ measurements. Results:The Fat% QCT of both 80 kV and 120 kV group positively correlated highly with biochemical extraction ( r s=0.936, P<0.001, r s=0.927, P<0.001) respectively. No statistically significant difference of Fat% QCT was detected between 80 kV and 120 kV group ( Z=-0.141, P=0.888). Bland-Altman analysis showed a small difference of Fat% QCT between the 80 kV and 120 kV group, in which mean values were 0.20%. Conclusions:Using biochemical extracted triglyceride as the reference, under the conditions of low-dose 80 kV and standard 120 kV tube voltages, QCT measurement of fat content is accurate and reliable in goose liver.

Objective To study the average difference of CHN atlas method bone age (BA) determination (left-vs.right-hand) for children and adolescents.Methods Radiographs of hands of healthy children and adolescent (age range:1.0-19.0 years) were analysed to determine BA,producing analysis results for 1380 hand images.The images were assessed by two radiologists based on CHN atlas method,who were blinded to the chronological age (CA) of them.The intra-and inter-observer variations were used for evaluating the reliability of CHN atlas method.The difference of BA using left-or right-hand BA was evaluated by t test.Results No significant difference was found for intra-or inter-observer variations (P ＞ 0.05).The BAs of left-and right-hand radiograph showed significant difference in the groups for boys (16.0-16.9,17.0-17.9 years),girls (6.0-6.9 years) and both of them (6.0-6.9,16.0-16.9 years).The regression model analysis showed no significant difference(t =-0.427,P =0.670).Conclusion Comparison of left-and right-hand BA shos no significant difference using CHN atlas method,indicating that either hand could be used to determine BA.