Objective To study on quenching free radical substances in antarctic ice alga.Methods Antarctic ice alga Berkeleya rutilans H-15 used as material,complete experiment of preparation free radical scavenging substances was established.All of these include the extraction of active substances by methanol,then pursuing and determination of the separation effect and change of active substances by DPPH and Godin method;the primary separation and purification by silica gel 60 column chromatogram;the farther purification by Sephadex LH column chromatogram and the purity determination of compound by HPLC.The type of compound and functional group of high pure compound were determined by the IR spectrum,HPLC-MS.Results One pure compound with strong activity was obtained from Berkeleya rutilans H-15,and it was confirmed to belong to phenol derives by analysis of IR spectrum and HPLC-MS.Conclusion It was completely feasible to find and acquire quenching free radical substances in antarctic ice alga,which initiated a new way to obtain natural antioxidant active substances from antarctic microorganism.

Objective To study on bioactive chemical compounds against ultraviolet irradiation in antarctic ice microalgae.Methods Four kinds of Antarctic ice microalgae were cultured under the conditions of low temperature,illumination,UV-A and UV-B irradiation.The chemical compounds were extracted by methanol and analyzed by spectrophotometer and HPLC/MS.The molecular structures were elucidated according to these data.The chemical compounds were irradated by sunshine to observe the speed of degradation and to estimate the bioactivity.Results There were five active compounds in Chlorophyceae L-4 and 7 active compounds in Diatom HF-9,in which 6 compounds belong to MAAs(mycosporine-like amino acids) and were of more bioactivity against ultraviolet irradiation.Conclusion MAAs from of Antarctic ice microalgae play an important role in resisting ultraviolet irradiation.

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 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 access the value of three dimensional gradient echo two-point Dixon water-fat separation sequence (3 D-DIXON) in quantitative diagnosis of non-alcoholic fatty liver disease(NAFLD) by comparing with in-phase/opposed-phase (IN/OPP)and proton magnetic resonance spectroscopy (1 H-MRS).Methods A total of 69 patients with NAFLD diagnosed by CT were divided into two groups by the ratio of liver spleen in CT (group A,low-grade fatty liver,n=32;group B,moderate and severe fatty liver,n=37).All patients underwent MR 3D-DIXION,1H MRS and IN/OPP examination twice within 1 week after CT examination.Fat fraction(FF) was evaluated and analyzed respectively.Results Pearson linear correlation analysis showed significant positive correlation between group A and group B about FF3D-DIXON,FFMRs and FFIN/OPP.Area under ROC curve (AUC) was different:AUCsYNTHESIZE＞AUCMRs＞AUCIN/OPP＞AUC3D-DIXON.Kruskal-Wallis H revealed significant difference among the three sequences no matter in group A or group B (P＜0.05).FF values of the three sequences (FF3D-DIXON,FFMRs and FFIN/OPP) were negatively correlated with CT liver/ spleen ratio in each group.The cut-off value of 3D-DIXON,IN/OPP and 1 H-MRS to diagnose presence or absence of fatty liver was 4.9 3 9 ％,5.2 8 4 ％ and 10.4 6 0 ％.Conclusion FF values measured by MRI methods might significantly vary based on different sequences.1 H-MRS is also the main method for quantitative assessment of fatty liver,3D-DIXON showed significant advantage in quantifying moderate and severe fatty liver.

Objective To observe the value of augmented reality(AR)navigation system for assisting CT-guided puncture of pulmonary nodules in dog models.Methods Five healthy dogs were selected,and 4 target lung rings were implanted in each dog to build pulmonary nodule models.Deferring to crossover design,CT-guided punctures were performed with or without AR navigation 2 and 4 weeks after successful modeling,respectively,while punctures with AR navigation were regarded as AR group and the others as conventional group,respectively.The time duration of puncturing,the times of CT scanning,of needle adjustment,and the deviation distance between needle pinpoint to the center of pulmonary nodule shown on three-dimensional reconstruction were compared between groups.Results The duration time of puncture in AR group and conventional group was(13.62±5.11)min and(20.16±4.76)min,respectively.In AR group,the times of CT scanning,of needle adjustment,and the deviation distance was 2.40±0.50,2.75±0.44 and(2.94±1.92)mm,respectively,while in conventional group was 3.10±0.64,3.70±0.57 and(4.90±3.38)mm,respectively.The introduction of AR navigation was helpful to shortening the duration of puncture,reducing times of CT scanning and needle adjustment,also decreasing positioning error of needle pinpoint(all P＜0.05).In contrast,the variance of puncture sequences and dogs had no obvious effect on the results(both P＞0.05).Conclusion AR navigation system could improve accuracy and efficiency in CT-guided puncture of pulmonary nodules in dog models.

Objective To investigate a novel stroke recurrence risk prediction model,which utilized radiomics machine learning methods and specifically combined carotid computed tomography angiography(CT A)with the Essen stroke risk score(ESRS).Methods A total of 136 patients who underwent carotid CT A were analyzed retrospectively.The features of carotid plaque were extrac-ted by machine learning to construct a radiomics feature model,as well as combined with ESRS.Based on clinical outcomes at one-year follow-up,the stroke recurrence risk prediction model was constructed using the logistic regression(LR)machine learning model.To construct an effective and robust model,the dataset was divided into a training set and a validation set in a ratio of 7∶3.The performance of this model was evaluated using area under the curve(AUC)of receiver operating characteristic(ROC)curve,sensi-tivity and specificity.Results The model had strong predictive value.In the training set,AUC,sensitivity and specificity of this model were 0.903,0.796 and 0.761,respectively.In the validation set,AUC,sensitivity and specificity of this model were 0.869,0.667 and 0.850,respectively.Conclusion The stroke recurrence risk prediction model constructed based on radiomics analysis of carotid plaque characteristics in carotid CTA,in combination with the ESRS,can provide reliable predictions for stroke prognosis.

Purpose To explore the application value of contrast enhancement boost(CE-Boost)technique in image quality of tumors and their feeding arteries in preoperative evaluation of renal cancer patients.Materials and Methods A total of 36 renal cancer patients in People's Hospital Affiliated to Shandong First Medical University from August 2022 to May 2023 with pathologically confirmed were retrospective collected.All patients underwent renal enhanced CT.The cortical phase images were post-processed using the CE-Boost technique to obtain CE-Boost images.The cortical phase images were set as group A and the CE-Boost images were set as group B.The CT value and image noise(SD)of abdominal aorta,renal artery,tumor and its adjacent renal cortex,and SD of the vertical spinal muscle on both sides of the spine of two groups were measured and recorded,and then the signal-to-noise ratio and contrast-to-noise ratio of tumor,abdominal aorta and renal artery were calculated.The image quality of the tumor,tumor feeding artery and renal artery was scored on 4 points by 2 doctors with double-blind method.Results The signal-to-noise ratio,contrast-to-noise ratio and CT value of group B were significantly higher than those of group A(t=-27.385--5.267,all P<0.05).The SD of tumor,abdominal aorta,right and left renal artery were not significantly different between group A and B(t=-1.849-0.993,all P>0.05).The subjective score of tumor in group A and B were no significant difference(Z=-1.490,P=0.136).However,the subjective score of tumor feeding arteries and renal arteries were significantly higher in group B than in group A(Z=-3.512,P=0.000;Z=-2.127,P=0.033).Conclusion The CT CE-Boost technique can improve the image quality of renal enhanced CT and provide visualization of tumor feeding arteries.

【Objective】 To explore the difference of demographics and influencing factors of motivations between whole blood donors and plasmapheresis donors, so as to provide scientific reference for effective recruitment strategy. 【Methods】 A total of 200 whole blood donors from Guangyuan Blood Center and 200 plasmapheresis donors from Jiange Plasmapheresis Station were selected in August 2021 for on-site questionnaire survey using the method of cross-sectional survey. Statistical analysis was performed by chi-square test, univariate and multivariate logistic regression. 【Results】 There were significant differences in gender, age, occupation, education level and annual family income between whole blood donors and plasmapheresis donors (P<0.05). Males accounted for a large proportion of whole blood donors(124/196, 63.3%), whereas females accounted for a large proportion of plasmapheresis donors(117/198, 59.1%). There was little difference in the number of whole blood donors in different age groups, while the age of plasmapheresis donors was concentrated in 40~59 years old (167/198, 84.3%). In terms of occupation, civil servants (including public institutions) accounted the highest proportion in whole blood donors (41/196, 20.9%), and farmers accounted the highest proportion (152/198, 76.8%) in plasmapheresis donors. The number of whole blood donors increased with the education level, and donors with college/university and above degree accounted the largest proportion (80/196, 40.8%). Plasmapheresis donors with junior middle school education and college/university and above accounted the largest and smallest proportion (49.5% vs 4.5%). The annual family income of whole blood donors ranged from 30 000 to 80 000 yuan accounted the largest proportion (109/196, 55.6%), and the annual family income of plasmapheresis donors less than 30 000 yuan accounted the largest proportion (132/198, 66.7%). 【Conclusion】 There were significant statistical differences in gender, age, education level, occupation and annual family income between whole blood and plasmapheresis donors. Therefore, targeted recruitment strategies should be formulated.

【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.