Computed tomography (CT) has become a very important method for preoperative examination for hilar cholangiocarcinoma.In this article,the multidetector helical CT findings of 20 patients with hilar cholangiocarcinoma who were confirmed by surgical pathological examination or biopsy in the Ruijin Hospital of Shanghai Jiaotong University from September 2010 to September 2012 were retrospectively analyzed to investigate the value of muhidetector helical CT in the diagnosis and resectability evaluation of hilar cholangiocarcinoma.All the 20 patients received dynamic contrast enhanced CT scanning after abdominal plain scanning,including arterial phase and portal venous phase scanning.Six patients received additional delayed phase scanning for 3-4 minutes.Muhi-phase reconstruction (MPR) and CT angiography were performed after the scanning.The location and sizes of lesious,the range of invasion of adjacent vessels,swelling of lymph nodes of hilar and retroperitoneum,and hepatic metastasis were recorded.The results showed that only 8 lesions were found on CT plain scanning,and they were presented as hypodense nodules.All lesions were showed on contrast enhanced images.Five cases with infiltrating type were showed as focal wall thickness of hilar bile duct,ringlike enhancement appeared on arterial phase scanning,and the enhancement was more apparent in portal venous and delayed phasc scanning.Eight cases with intraductal growing type demonstrated as intraductal nodules,obvious enhancement was detected on delayed phase scanning,and the dilation of intrahepatic bile duct was also found.Seven cases of tumoral type showed as mass located in hilar region and involved adjacent vessels and partial hepatic parenchyma.Diffused or local dilation of bile duct could be seen on CT images.Combination of 2and 3-dimensional reconstruction images can show more clearly of hilar cholangiocarcinoma lesions,invasion of hepatic arery or portal vein,segmental atrophy and metastasis of lymph nodes and liver.One-stop CT examination combined with axial multiphase dynamic contrast enhanced scanning with MPR and CT angiography of multidetector helical CT can clearly show the lesions of hilar cholangiocarcinoma,improve the preoperative tumor staging and help to design the surgical treatment.

The clinical data,endoscopic and CT findings of 39 patients with Crohn's disease(CD) and 24 patients with intestinal tuberculosis (ITB) were retrospectively reviewed.Diarrhea,hematochezia,perianal disease,intestinal obstruction,occurred more frequently in CD than in ITB (P ＜0.05 or ＜0.01).Night sweating,febrility,pulmonary tuberculosis and ascites were more common in ITB than in CD (P ＜0.01).The endoscopic findings showed that longitudinal ulcer,cobblestone sign,intestinal stricture were detected more often in CD than in ITB (P ＜ 0.05 or ＜ 0.01),but transverse ulcer and rodent ulcer were more frequently found in ITB than in CD (P ＜0.05 or ＜0.01).On the CT imaging mural gas,fat,enteric cavity stenosis and layering thickening were more common in CD than in ITB (P ＜ 0.05 or ＜ 0.01),but mural single layer thickening and hollow lymph nodes were discovered more frequently in ITB than in CD (P ＜ 0.01).The degree of intestinal wall thickening,enhancement and lymph nodes enlargement of ITB were more severe than that of CD (P ＜ 0.01).The clinical manifestations combined with endoscopic and CT finding may improve the differential diagnosis between Crohn's disease and intestinal tuberculosis.

Objective To study the impact of main source voltage fluctuation on dose rate and dose delivery accuracy of BJ-6B accelerator. Methods The accelerator was calibrated by a voltage regulator at an output voltage of 332 V. The main source voltage fluctuation was simulated by changing the output of voltage regulator within the range of 321 - 338 V. The change of dose rate was recorded. Using a water phantom, each absorption dose was measured five times and averaged along the central beam axis at the depth of 1.5 cm, 5 cm and 10 cm, respectively, with the conditions of monitor unit: 100 MU ,field: 10 cm× 10 cm and SSD = 100 cm. The impact of voltage fluctuation on dose rate and dose delivery of BJ-6B accelerator was analyzed. Results Voltage fluctuation had an significant effect on dose rate. In a certain range, dose rate and absorption dose at different depths increased as the output voltage increased. Conclusions It is essential to equip the BJ-6B accelerator with a high accurate voltage stabilizer, and the voltage stabilizer must be adjusted to its highest accuracy.

sed by pelvic fracture or other conditions.

Objective To study the effect of CT scanning condition on the target position coordinate with WIMRT radiotherapy planning system using the" Z" form localizing frame. Methods The whole Head Phantom containing three metal targets was scanned under the following conditions: localizing frame transver-sally tilting, CT gantry tilting and localizing frame axially tilting. Then the three target coordinates were com-puted respectively and compared with those under the standard condition. Results The height and width of coordinate under the localizing frame transversally tilting condition deviated from those under the standard scanning condition,which was in an angle dependent manner. On the other hand ,a tendency was shown that the greater the absolute height value of the targets coordinate, the greater the width value deviation. And so was the relation between the absolute width value of the coordinate and height value deviation. If CT gantry angle was not zero degree or localizing frame axis is not in the same line with the CT bed moving direction, the calculated longititude value of the targets coordinate was mainly affected. Conclusions CT scanning must be performed strictly under the standard localizing scanning condition by a proficient physicist.

Objective To study the maintenance of BJ-6B accelerator. Methods Analyzed retrospectively the maintenance record of BJ-6B accelerator, including phenomena, causes and handle from 2002 to 2009. Results In 231 records, there were motion-controlling 64, hand-controlling-pendant 20.modulator 41, anti-peak overload 36, charging overload 5. Flatness 7, mechanical 21, digital-display 20,others lie in magnetron power, water-cooling system, light-indicator system, dose-monitor system and wedge system. Motion-controlling system is the highest among those, followed by high-voltage modulator and mechanical system. Conclusions The down time for BJ-6B accelerator is low because of its perfect technology. To keep its stability in clinic, the hospital authorities should emphasize training of engineer for improving their maintenance ability. The engineer must be familiar with the circuit diagram, check the electric wire and machine unit on time and prepare unit for maintenance. The temperature and humidity in machine house must be controlled on demand. The engineer must pay attention to machine parameters when beam is on for avoiding the spark's damage to magnetron and accelerating-tube

Objective To investigate the relationship between RAD51 135G ＞ C polymorphism and prognosis in triple-negative breast cancer patients by retrospective analysis.Methods The clinical data of 62 triplenegative breast cancer patients were collected.The 62 cases underwent standard chemotherapy and radiotherapy after tumor resection from Jan.2004 to Dec.2010 in Affiliated Cancer Hospital of Zhengzhou University.RAD51 135G ＞ C polymorphism was detected by polymerase chain reaction-restriction fragment length polymorphism (PCR-RELP) technology.The survival curve about progress free and overall survival time were then made.Results The median progress free and overall survival time in triple-negative breast cancer patients with or with-out RAD51 135G ＞ C polymorphism were(77.00 ±5.55)and(89.00 ± 10.40) months vs(99.00 ±4.26)and (103.00 ±4.30) months.The difference had statistical significance(P =0.039 and 0.015 respectively).Conclusion RAD51 135G ＞ C polymorphism is related with prognosis of triple-negative breast cancer patients,which might be a prognostic factor for breast cancer.

AIM: To prepare and characterize a mouse anti-human CD40 mutant monoclonal mAb. METHODS: Female BALB/c mice of 6-8 weeks old were immunized with CD40 mutant transfectant (L929-CD40mu) as immunogen. The spleen B cells of the mice were fused with Sp2/0 myeloma cells. The hybridoma cells were screened with CD40 mutant transfectant (L929-CD40mu) by FCM. Faststrip analysis was performed to identify Ig subclass of this mAb. The epitope recognized by this mAb was detected by Bio-5C11 competitive assay. Western blot technique was adopted to identify the mAb. The proliferation of tumor cells in vitro was analyzed by MTT assay and apoptosis of tumor cells in vitro was analyzed by PI-annexin V assay. RESULTS: One hybridoma cell line named 10C5 was obtained, which had the property of secreting anti-human CD40 mutant monoclonal antibody continuously and steadily. This mAb specifically recognized human CD40 mutant molecule and induced the apoptosis of tumor cells in vitro. CONCLUSION: One hybridoma cell line which can secret a mouse anti-human CD40 mutant mAb has been prepared successfully. This mAb can inhibit the growth of tumor cells expressing CD40 mutant and induce their apoptosis in vitro.

Objectives To explore the value of Silenz MRA in the follow-up assessment of intracranial aneurysms embolization. Methods Fifteen patients underwent coiled embolization were prospectively collected. Silenz and time of flight MRA (TOF MRA) were performed on the same day as DSA examination. Two neuro-radiologists scored the structures of peripheral vascular with a 4-score grading system and evaluate embolism status (two-grade montreal scale). The scores of vascular structures were compared using Wilcoxon signed rank tests. Weighted Kappa statistics was used to assess the inter-observer agreement on each MRA scoring, the inter-modality agreement between MRA and DSA, the inter-modality agreement between the MRA methods. Results There were 11 cases with complete occlusion, 4 cases with residual aneurysm revealed by DSA. For depiction, Silenz MRA was significantly better than TOF MRA [(3.50 ± 0.62) vs. (3.00 ± 0.63), Z=-3.12, P=0.002]. Inter-modality agreement of Silenz MRA and DSA was excellent (Kappa=0.82), while the agreement of TOF MRA and DSA was moderate(Kappa=0.60). Inter-modality agreement between Silenz MRA and TOF MRA was good (Kappa=0.76). Conclusions Silenz MRA is superior to TOF MRA for depiction of vascular structures and evaluation of embolism status, which is highly related with DSA. It has the value in the postoperative follow-up evaluation.

Objective To investigate the effect of spectral CT monochromatic images for improving imaging quality in hepatic venography.Methods Thirty patients underwent spectral CT examination on a GE Discovery CT 750 HD scanner.During portal phase,1.25 mm slice thickness polychromatic images and optimal monochromatic images were obtained,and volume rendering and maximum intensity projection were created to show the hepatic veins respectively.The overall imaging quality was evaluated on a five-point scale by two radiologists.Inter-observer agreement in subjective image quality grading was assessed by Kappa statistics.Paired-sample t test were used to compare hepatic vein attenuation,hepatic parenchyma attenuation,CT value difference between the hepatic vein and the liver parenchyma,image noise,vein-to-liver contrast-to-noise ratio (CNR),the image quality score of hepatic venography between the two image data sets.Results The monochromatic images at 50 keV were found to demonstrate the best CNR for hepatic vein.The hepatic vein attenuation[(329 ± 47) HU],hepatic parenchyma attenuation [(178 ± 33) HU],CT value difference between the hepatic vein and the liver parenchyma [(151 ± 33) HU],image noise (17.33 ±4.18),CNR(9.13 ±2.65),the image quality score(4.2 ±0.6) of optimal monochromatic images were significantly higher than those of polychromatic images[(149 ± 18) HU],[(107 ± 14) HU],[(43 ±11) HU],12.55 ± 3.02,3.53 ± 1.03,3.1 ± 0.8 (t values were 24.79,13.95,18.85,9.07,13.25 and 12.04,respectively,P ＜ 0.01).In the comparison of image quality,Kappa value was 0.81 with optimal monochromatic images and 0.69 with polychromatic images.Conclusion Monochromatic images of spectral CT could improve CNR for displaying hepatic vein and improve the image quality compared to the conventional polychromatic images.