Objective To evaluate the association between LDL-C and ischemic stroke in patients with nonvalvular atrial fibrillation (AF).Method A total of 2 470 patients with nonvalvular AF were included in the present study.The clinical data and laboratory examination results of the patients in the hospital were collected.The subjects were either divided into the ischemic stroke history (n =560),and non-ischemic stroke history groups (n =1 910),or divided into the low-middle risk (n =566) and high risk groups (n =1 904) based on CHA2 DS2-VASc score.Results There were significant differences in the proportion of Han,the ratio of gender,age,hemoglobin,hematocrit,ALT,serum uric acid,HDL-C and LDL-C between the patients with ischemic stroke history and without (all P ＜ 0.05).Similarly,there were significant differences in the proportion of Han,the ratio of gender,age,white blood cell count,hemoglobin,hematocrit,platelet count,ALT,albumin,TG and LDL-C between subjects in the low-middle risk group and those in the high risk group (all P ＜ 0.05).A logistical regression analysis showed that LDL-C was an independent risk factor for both the ischemic stroke history (OR 2.089,95％ CI 1.860-2.347,P ＜0.05),and future ischemic stroke risk (OR 1.270,95％ CI 1.079-1.494,P ＜ 0.05) in patients with nonvalvular AF.Conclusion LDL-C is associated with ischemic stroke in patients with nonvalvular AF,and it is also an independent risk factor for future ischemic stroke in these patients.

Objective To understand the review situation of medical ethics in scientific research and prevention and control of endemic diseases,raise awareness of ethical review,and to promote rapid and healthy development in scientific research for control of endemic diseases.Methods The method of retrospective analysis was used,articles on original articles,field epidemiological investigations and clinical medicines published by Chinese Journal of Endemiology from 2013 to 2016 were collected.Examination of medical ethics in national,provincial and municipal fund programs and non fund projects was carried out.Statistical analysis was performed using Cochran-Armitage trend test and Cochran-Mantel-Haenszel (CMH) test.Results A total of 642 articles were collected from 2013 to 2016 and 25 articles were excluded.①The total number of papers published after medical ethics review was in a upward trend,the difference was statistically significant in trend test (Z =4.84,P ＜0.01);and the papers were increased from 14.8％ (20/135) in 2013 to 38.2％ (66/173) in 2016 and compared among different years,the differences were statistically significant (x2 =23.43,P ＜ 0.01).The papers of original articles and field epidemiological investigations published were in a upward trend,the difference was statistically significant in trend test (Z =4.32,2.14,P ＜ 0.01 or ＜ 0.05);and the papers were increased from 12.3％ (7/57),13.2％ (9/68) in 2013 to 48.6％ (36/74),27.3％ (24/88) in 2016 and compared among different years,the differences were statistically significant (x2 =18.61,4.57,P ＜ 0.01 or ＜ 0.05).②The total number of papers published which was supported by various fund programs that had past the medical ethical review was in a upward trend,the difference was statistically significant in trend test (Z =5.27,P ＜ 0.01);and the papers were increased from 13.3％ (14/105)in 2013 to 42.4％ (53/125) in 2016,compared among different years,the differences were statistically significant (x2 =27.69,P ＜ 0.01).The total number of papers published in the national,provincial programs was in a upward trend,the difference was statistically significant in the trend test (Z =4.14,3.21,P ＜ 0.01);and the papers were increased from 16.0％ (8/50),10.0％ (5/50) in 2013 to 51.7％ (31/60),32.7％ (17/52) in 2016,compared among different years,the differences were statistically significant (x2 =17.05,10.27,P ＜ 0.01).③The total number of papers published and approved or marked with approval numbers by the ethics committee was in a upward trend,the difference was statistically significant in trend test (Z =5.74,5.44,P ＜ 0.01);and the papers were increased from 0.7％ (1/135),0 (0/135) in 2013 to 21.4％ (37/173),11.0％ (19/173) in 2016,compared among different years,the differences were statistically significant (x2 =32.90,29.55,P ＜ 0.01).④The total number of papers published with informed consent or signed was in a upward trend,the difference was statistically significant in trend test (Z =2.56,2.14,P ＜ 0.05);and the papers were increased from 15.6％ (21/135),4.4％ (6/135) in 2013 to 26.6％ (46/173),11.0％(19/173) in 2016,compared among different years,the differences were statistically significant (x2 =6.54,4.60,P ＜ 0.05).Conclusions Medical ethical review is more and more widely used in scientific research and prevention and control of endemic diseases;scientific research workers attach great importance to the ethics review of research projects.However,there are still omissions and missing reports in some projects and articles.The editorial department and editors need to guide the author to raise the author's understanding of the importance of ethical review.

Objective To investigate the clinical application value of wrist joint ulnar deviation supination 45° palmar oblique posi-tion in the diagnosis of scaphoid waist fracture and displacement.Methods The imaging and clinical data such as digital radiography(DR),CT of 93 wrist joint trauma patients were analyzed.The four position views including wrist joint anteroposterior+lateral view,scaphoid position,wrist joint ulnar deviation supination 45° palmar oblique position,scaphoid position+wrist joint ulnar devia-tion supination 45° palmar oblique position were analyzed by three readers.The consistency of the evaluation among different readers and the diagnostic efficiency of the diagnosis of scaphoid fracture and displacement were compared.Results The inter-observer agreement,sensitivity,specificity,accuracy,and other diagnostic efficiency of scaphoid waist fracture and displacement was evaluated,wrist joint ulnar deviation supination 45° palmar oblique position+scaphoid position and wrist joint ulnar deviation supination 45° palmar oblique position were better than those of scaphoid position and wrist joint anteroposterior+lateral view.The combination of wrist joint ulnar deviation supination 45° palmar oblique position+scaphoid position obtained the best diagnostic efficiency.Conclusion The wrist joint ulnar deviation supination 45° palmar oblique position shows the long axis of the scaphoid,which has a high diagnostic efficiency in the diagnosis of scaphoid waist fracture and displacement and would be used as a useful supplement to other scaphoid imaging.

Objective To investigate the optimal scanning parameters for cone beam computed tomography(CBCT)of the nasal bone,to achieve low-dose scanning of the nasal bone CBCT.Methods Utilizing Prangmerka CBCT 3D single-tooth sequence,nasal bone scans were performed on two human-equivalent phantoms using two dose protocols,five body types,and five resolutions,resul-ting in 50 scanning sequences.The dose area product(DAP)and volume CT dose index(CTDIvol)were recorded.Objective image quality assessment was conducted by calculating the contrast-to-noise ratio(CNR),signal-to-noise ratio(SNR),noise,and figure of merit(FOM)in region of interest(ROI)set on sagittal images.Subjective scoring was performed using a five-point Likert scale.Differences in radiation dose and image quality among various scanning parameters were compared and analyzed.Results(1)Signifi-cant differences in DAP were observed among different dose modes,body types,and resolutions(P＜0.05),with the lowest DAP values recorded for the XS body type.(2)Statistically significant differences in CNR,SNR,noise,and FOM were found among differ-ent dose modes and resolutions(P＜0.05).The XS body type exhibited the highest SNR and FOM values and the lowest noise.The 200 μm resolution demonstrated the higher CNR value and the highest SNR value,with moderate noise and FOM value.(3)Signifi-cant differences in image quality,contrast,sharpness,and noise were observed among different dose modes,body types,and resolu-tions(P＜0.05).Higher subjective scores were assigned to the 200 μm and 150 μm resolutions,indicating clear anatomical details.Conclusion The scanning parameters of 200 μm resolution combined with an ultra-low-dose protocol for the XS body type achieve a balance between low radiation dose and high image quality,making them suitable for low-dose nasal bone CBCT examinations.

Objective To investigate the removal of metal artifacts caused by different metal implants in different parts of the human body using dual-energy CT and to select the best method for metal artifacts reduction.Methods Forty-three patients with metal implants underwent dual-energy CT scans.Reconstructed images were obtained to produce eight sets of imaging data:conventional image(CI),120 keV,140 keV,160 keV,180 keV,200 keV,Orthopedic metal artifact reduction algorithm(O-MAR),200 keV+O-MAR.The optimal spectral monoenergetic images was selected based on the trend of changes in artifact index(AI)values with different keV monoenergetic images and subjective evaluation.One-way ANOVA was used to analyze and compare objective image evaluation indi-cators and subjective evaluations of image quality among different groups.The intraclass correlation coefficient(ICC)was used to evaluate the consistency and reliability of subjective evaluations of image quality among different observers.Results The AI values of differ-ent keV monoenergetic images showed a decreasing trend with increasing keV,and the virtual monoenergetic images at the 200 keV level had the smallest AI value.There were statistically significant differences in objective indicators for the removal of high-density artifacts and low-density artifacts among the groups(P＜0.05).Pairwise comparison showed statistical differences between CI and O-MAR,CI and O-MAR+200 keV,200 keV and O-MAR,200 keV and O-MAR+200 keV(P＜0.05),with O-MAR+200 keV demon-strating the best objective indicators.The ICC for subjective evaluation among different observers was 0.97％,and the ICC within observers was 0.91％.There were statistically significant differences in subjective image scores among the groups(P＜0.05),with the CI had the lowest score[(1.04±0.24)points]and the O-MAR+200 keV combination had the highest score[(4.57±0.78)points].Conclusion Dual-energy CT virtual monoenergetic 200 keV spectroscopy combined with O-MAR technique can be used as the best technique for removing metal implant artifacts and achieving better contrast in the surrounding soft tissue of prostheses.

Objective:To learn about the application of medical ethics review in scientific research and prevention of endemic diseases.Methods:The method of retrospective analysis was used, original articles on field epidemiological investigation and clinical medicines published by Chinese Journal of Epidemiology from 2017 to 2020 were collected. Examination of medical ethics in national, provincial and municipal fund programs and nonfund projects was carried out. Statistical analysis was performed using Cochran-Armitage trend test and Cochran-Mantel-Haenszel (CMH) test.Results:A total of 638 articles were collected from 2017 - 2020, with 36 excluded and 602 remaining. The proportion of papers published after medical ethics review over the past four years was 56.85% (83/146), 62.50% (105/168), 59.87% (94/157), and 60.31% (79/131), respectively. There was no statistically significant difference in trend testing ( Z = 0.41, P > 0.05). There was no statistically significant difference in the proportion of papers produced by academic works, on-site investigations, and clinical medicine programs among different years (χ 2 = 0.01, 1.31, 1.92, P > 0.05). The proportion of papers published that supported by various fund programs that had undergone medical ethics review over the past four years was 60.55% (66/109), 62.28%(71/114), 62.38% (63/101), and 60.22% (56/93), respectively. The trend test showed no statistically significant difference( Z = - 0.03, P > 0.05). There was no statistically significant difference in the proportion of papers published that supported by national level projects, provincial and ministerial level projects, and municipal level projects among different years (χ 2 = 0.06, 0.02, 0.19, P > 0.05). The difference in the trend test of the output papers of research projects approved by the higher-level ethics committee and marked with approval numbers over the past 4 years was statistically significant ( Z = 2.85, P < 0.01); the difference was statistically significant when compared across years (χ 2 = 8.13, P < 0.01); the proportion of papers increased from 8.22% (12/146) in 2017 to 18.08% (25/131) in 2020 (χ 2 = 7.04, P = 0.008). There was no statistically significant difference ( Z = - 0.53, P > 0.05) in the proportion of papers that expressed their consent in terms of informed consent over the past 4 years; There was no statistically significant difference in comparison between different years (χ 2 = 0.28, P > 0.05). Conclusions:Medical ethics review has been taken seriously by the majority of researchers and is widely used in endemic scientific research and prevention projects.