The medical education of China and the United States was compared by analyzing the differences about educational system, teaching mode and teaching content in this paper. Standard-ization of the Chinese medical education system, improving clinical practice, teaching students by initi-ating questions and advanced medical education technology were recommended in China. This paper will inspirit and provide experience for the innovation of Chinese medical education.

Objective To study the accuracy,clinical value and limit in assessing the vessels surrounding pancreas involved by pancneutic carcinoma with low field MRI.Methods MRI scanning was performed in 55 patients with pancreatic carcinoma.We prospectively evaluated the MRI findings of vascular involvement by pancreatic carcinoma,and compared with the surgical results.Results Of total 55 cases,50(91%)cases were correctly diagnosed on MRI .MRI carries an accuracy of 86% for prediction of resectility,and accuracy of 93% for unresectility.Conclusion Low field MRI can accurately assess the peripancreative vessels ,but it has limited value in the patients with pancreatic carinomaⅠa orⅠb.

Objective To investigate whether two-dimension speckle tracking imaging(2D-STI) and ICAM-1-targeted myocardial contrast echocardiography could detect the acute cellular rejection of heart transplantation at the early stage.Methods The abdominal heterotopic heart transplantation model was successfully established using Wistar and SD rats.Forty-eight rats were divided into allografts (ALLO) group (n =24) and isografts(ISO) group (n =24).Echocardiography,2D-STI and ICAM-1 targeted myocardial contrast echocardiography were performed at 1,3,5 day after transplantation respectively.After ultrasound imaging,transplanted hearts were harvested for Hematoxylin-eosin staining and immunofluorescence histochemistry to evaluate acute cellular rejection and ICAM-1 expression.Results There were obvious difference between ALLO group and ISO group in echocardiographic parameters at 5 days after transplantation surgery (all P ＜0.05).Compared with those in ISO group,global circumferential strain and strain rate (GCS,GCSr),and circumferential strain of endo-myocardium (CSendo) decreased in ALLO group at day 3 post-transplantation (all P＜0.05).Compared with those in ISO group,all strain parameters in ALLO decreased significantly at postoperative day 5 (all P＜ 0.05).Myocardial contrast echocardiography using ICAM-1-targeted microbubbles showed that the video intensity in ALLO group was significant higher than that in ISO group at postoperative day 3 and day 5 (all P＜0.05).Conclusions 2D-STI and myocardial contrast echocardiography using ICAM-1-targeted microbubbles are sensitive and useful for detecting heart transplant acute rejection at the early stage.

Objective To evaluate the value of 1.5T MRI in differential diagnosis of circular enhanced brain lesions.Methods A total of 120 patients,admitted to our hospital from April 2009 to March 2013 and confirmed by clinical pathology,including 40 of brain metastasis,40 of astrocytoma and 40 of brain abscess,were chosen in our study; The characteristic signs of MRI findings of these patients were retrospectively analyzed.Results There were significant differences in the location,number,size,morphology,ring structure,multiple mural nodules,and smooth outside wall of the lesions between patients with brain metastasis and astrocytoma.There were significant differences in the number,size,ring structure,ring wall thickness,and smooth outside wall of the lesions,T2-weighted imaging (T2WI) low signal ring sign,hydraulic fluid level sign,lesion center diffusion weighted imaging (DWI) hyperintensity and apparent diffusion coefficient (ADC) map low signal between patients with brain metastasis and abscess.There were significant differences in the location,shape and multi locular lesions between patients with astrocytoma and abscess.The signs indicating brain metastasis included multi lesions,grade Ⅲ peripheral edema,small lesions,lesions located at the juncture of gray and white matter,with displaying percentages of 79.5％,70.3％,67.5％,48.5％ and 47.9％.The signs indicating astrocytoma included multi locular lesion,lesions located at the white matter,multi mural nodule,rough outside wall and irregular in shape,with displaying percentages of 85.7％,78.0 ％,77.8％,65.4 ％ and 51.9％.The signs indicating abscess included daughter ring sign,DWI hyperintensity and ADC map low signal,circular wall notch sign,hype-intensity rim on T2WI and fluid-fluid level,with displaying percentages of 100％,100％,100％,92.6％ and 82.4％.Conclusion The 1.5T MRI can displaythe characteristic signs of brain metastases,gliomas and brain abscess,which enjoys high value in differential diagnosis.

Objective To explore the diagnostic value of thyroglobulin measurement with fine‐needle aspiration ( FNA‐Tg ) in detecting papillary thyroid carcinoma ( PTC ) metastatic lymph nodes ,and analyze the impact of different factors on the diagnostic accuracy of FNA‐Tg . Methods One hundred and fifty‐four lymph nodes from 138 patients w ho underwent total thyroidectomy and cervical lymphadenectomy were enrolled . Ultrasonography ,fine needle aspiration cytology ( FNAC) and FNA‐Tg results were acquired in all patients . T he diagnostic value of FNAC ,FNA‐Tg and the combination of the two methods were compared in suspicious PTC metastatic lymph nodes . T he influence of lymph nodes size ,lymph nodes cystic change and serum thyroglobulin antibody( TgAb) on the accuracy of FNAC and FNA‐Tg were analyzed . Results T he sensitivities of FNAC ,FNA‐Tg ,and the combination of the two methods in the diagnosis were 79 .5% , 95 .5% and 97 .7% ,respectively . T he specificities were 100% ,93 .9% and 100% ,respectively . T he size and cystic change of lymph nodes had effects on the accuracy of FNAC( P ＜0 .05) ,w hile they had no effect on the accuracy of FNA‐Tg ( P ＝0 .42 ,0 .67 ) . T he serum TgAb level had no influence on the accuracy of FNAC and FNA‐Tg ( P ＝ 0 .88 ,0 .34 ) . Conclusions FNA‐Tg is sensitive to metastatic lymph nodes in PTC w hich not affected by the lymph nodes size ,the lymph nodes cystic change and serum TgAb level . Application of FNA‐Tg with FNAC can improve the sensitivity of diagnosis ,w hich is important in the diagnosis of PTC metastatic lymph nodes .

Objective To investigate the impact of prescribed adaptive statistical iterative reconstruction V (Pre-ASiR-V) on imaging quality and radiation dosage of pure ground glass nodules (pGGN) in chest phantom,in order to obtain the optimal level of Pre-ASiR-V.Methods CT scanning for a chest phantom containing 4 artificial pGGNs was performed with Revolution CT,and the Pre-ASiR-V level was set as 0,20％,40％,60％,80％ and 100％ group,respectively.The mean noise,effective dose (ED) and the subjective scores of pGGN imaging were recorded and compared.Results The mean noise of groups (Pre-ASiR-V 0,20％,40％,60％,80％ and 100％) was (17.93±2.20)HU,(17.30±3.68)HU,(18.20± 3.44)HU,(18.80±0.20)HU,(19.87±2.56)HU and (15.90±4.56)HU,respectively (F=0.568,P=0.723).ED of these groups was 7.40 mSv,5.16 mSv,3.36 mSv,1.97 mSv,0.97 mSv and 0.33 mSv,respectively.Compared with imaging of PreASiR-V 0,the reduction percentage of ED was 30.27％,54.59％,73.38％,86.89％ and 95.54％,respectively.The subjective score of the image quality evaluated by the 2 observers had high agreement (Kappa=0.778,P=0.003),and all the scores were greater than 3.The subjective score of Pre-ASiR-V 80％ and 100％ group was slightly lower than those in other groups.Conclusion Different Pre-ASiR-V level slightly impacts the noise of high-resolution CT images of chest phantom,while reduces radiation dosage significantly.Pre-ASiR-V level of 60％ is the optimal protocol.

Objective To investigate the application value of shear wave elastography (SWE) combined with superb micro-vascular imaging (SMI) in differentiating malignant and benign thyroid masses.Methods Seventy-eight patients diagnosed by ultrasound and verified with postoperative pathological analysis were enrolled.Conventional two-dimensional ultrasound was applied to observe the masses.SWE was performed to evaluate the elasticity and the Young's modulus (AveT1) value acquired.ROC curve was drawn to calculate the sensibility and specificity using the cut-off value of AveT1.SMI was applied to define Adler's grading standard according to the degree of blood supply.The sensitivity,specificity and accuracy of SWE and SWE combined with SMI in differentiating malignant and benign thyroid masses were analyzed.Results ①According to pathological analysis,there were 42 benign and 44 malignant masses;②The AveT1 value between malignant and benign groups were all significantly different (P ＜0.01).41.4 kPa was used as the best cut-off value of AveT1.The area under the ROC curve were 0.83 with sensitivity 86.9％ and specificity 88.1％;③There were more masses with the Alder class Ⅱ-Ⅲ in malignant group than those in benign group,and the difference was statistically significant (P ＜0.01);④Quantified with SWE or SWE combined with SMI,the sensitivity were 86.9％ and 91.3％,specificity were 88.1％ and 92.8％,and accuracy were 87.5％ and 94.1 ％,respectively,and the difference was statistically significant (P ＜ 0.01).Conclusions SWE combined with SMI represents an excellent application value in differentiating malignant and benign thyroid masses,which could improve the sensitivity,specificity and accuracy of the diagnosis for thyroid masses using ultrasound.

Objective:To design a lung function prediction method that combines transfer learning and multimodal feature fusion, aiming to improve the accuracy of lung function prediction in patients with idiopathic pulmonary fibrosis (IPF).Methods:CT images and clinical text data were reprocessed, and an adaptive module was designed to find the most suitable lung function attenuation function for IPF patients. The feature extraction module was utilized to comprehensively extract features. The feature extraction module comprises three sub-modules, including CT feature extraction, clinical text feature extraction, and lung function feature extraction. A multimodal feature prediction network was used to comprehensively evaluate the attenuation of lung function. The pre-trained model was fine-tuned to improve the predictive performance of the model.Results:Based on the OSIC pulmonary fibrosis progression competition dataset, it is found through the adaptive module that the linear attenuation hypothesis is more in line with the trend of pulmonary function decline in patients. Different modal data prediction experiments show that the model incorporating clinical text features has better predictive ability than the model using only CT images. The model combining CT images, clinical text features, and lung function features have optimal predictive results. The lung function prediction method combining transfer learning and multimodal feature fusion has modified version of the Laplace log likelihood (LLLm) of ?6.706 5, root mean squared error (RMSE) of 184.5, and mean absolute error (MAE) of 146.2, which outperforms other methods in terms of performance. The pre-trained model has higher prediction accuracy compared to the zero base training model.Conclusions:The lung function prediction method designed by combining transfer learning and multimodal feature fusion can effectively predict the lung function status of IPF patients at different weeks, providing important support for patient health management and disease diagnosis.

【Objective】 To analyze the characteristics and mobility of the overlapping population of voluntary blood donation and plasmapheresis donation, so as to provide a scientific basis for the formulation of recruitment and retention strategies for blood donation and plasmapheresis donation, and to further propose a scientific reference for the decision-making of blood banks and plasmapheresis station management in China. 【Methods】 The basic information of blood donors and plasmapheresis donors in two counties in Guangyuan, Sichuan Province, which carried out whole blood collection and plasmapheresis collection from the establishment of the station to July 31, 2021 was statistically compared and analzed using the chi-square test and Post hoc testing test. 【Results】 As of July 31, 2021, a total of 50 658 people participated in blood donation and 63 375 people participated in plasmapheresis donation in Jiange County and Cangxi County, with a total overlap of 6 189 people. In the two regions, 16 458 (35.2%) people aged 40 to 50, and 35 558 people (56.1%) were over 50 years old. Among the overlapping population, 2 496 (40.3%) were 40 to 50 years old, accounted for the largest proportion, and 3 146 (50.8%) were males. Significant differences were noticed in age (P<0.001) and gender (P<0.001). There was a shift in dontion in 5 183, including 2 072 people from plasma to blood and 3 111 people from blood to plasma, among which 2 671 (51.5%) were men and 3 632 (70.1%) were over 50 years old, with significant differences in gender (P<0.05) and age (P<0.001). 【Conclusion】 There were a small number of donors donating both blood and plasma in Jiange and Cangxi, and men aged 40 to 50 were the majority, and people over 50 years old were more likely to shift the donation goals. The vast majority of donors have a single and fixed donation goal (blood or plasma), and are not easy to change.

【Objective】 To analyze the dynamic relationship between the setting up of plasmapheresis station and the volume of voluntary blood donation collected using panel vector autoregressive model, so as to provide scientific reference for the management policies of blood stations and plasmapheresis stations in China. 【Methods】 The data collected from blood stations in seven administrative regions of Guangyuan, Sichuan Province from 2011 to 2021, as well as plasma collection data from two plasmapheresis stations in the region within two years since their operation, were collected. A panel vector autoregressive model was constructed. Impulse response analysis and variance decomposition analysis were used to analyze the impact and time lag effects of simulated plasmapheresis station settings on the collection volume of voluntary blood donation. Covariance analysis was used to explore whether the establishment of plasmapheresis station had an impact on the volume of voluntary blood donation collected after excluding the impact of initial value differences. 【Results】 The pulse response results showed that after the plasmapheresis station was set up, there was a negative impact effect on the voluntary blood donation collection volume at the first stage, and its impact began to rise after the second stage, reached the highest value in the third stage, and then began to decline. After the seventh stage, it tended to be stable. However, within the 10 stage range, the confidence interval for the response strength of voluntary blood donation collection volume always included 0, indicating that the response of blood collection volume to the plasmapheresis station setting in the region was not statistically significant. The results of variance decomposition showed that the contribution of collection volume of voluntary blood donation to their own impact reached 94.3%. In terms of the contribution of plasmapheresis station factors, the number of plasma donors has a relatively greater impact on the volume of voluntary blood donation collected(2.2%). Covariance analysis showed that after removing the initial confounding factors, whether to establish a plasmapheresis station had no significant impact on blood donation volume in the two groups of regions (P>0.05). 【Conclusion】 The establishment of a new plasmapheresis station will have a certain impact on blood collection volume of blood stations in the region in a short term, but in the long term, it may not directly affect the voluntary blood donation collection in the region.