Objective:To explore the feasibility of long board detector of digital radiography(DR)in clinical application.Methods:The long board detector(detector)was erected and placed upright.The scale long ruler with marked metal lead wire was placed at 20 cm in front of the center of long axis of the board of detector,which paralleled medial axis.Three test cards of spatial resolution were respectively placed at three positions(upper,middle and lower)of detector,and they were stuck on the board of detector as 30cm intervals between each other and 45° position.The exposures were conducted at 100,150,and 200 cm of source image distance(SID).The incident doses were tested,which obtained from different SID spots of upper,middle and lower positions of detector.The spatial resolutions of 3 positions were determined through observed the images of cards.The ratio of the marked scale length with metal lead wire to actual length of lead wire was measured through the projection of the scale length,so as to obtain the amplification rate of different spot positions.The spatial distribution of effective focal plane on the direction of long axis of detector,and the morphological change of that were observed.Results:When SID spots were respectively 100,150 and 200cm,the amplification rates of images decreased with increasing SID.The difference of amplification rates among three SID spots was significant(F=223.80,P<0.001).There was significant difference in the corresponding radiation doses among different SID spots(F=7.57,P<0.05).The spatial resolution was constantly 1.8 LP/mm.There was heel effect along with the direction of short axis of detector.The effective focal spot on the direction of long axis of detector appeared up-down symmetrical display.Conclusion:The long board detector of DR equipment has realized the capture for the images of the overall length of spine or the overall length of lower limbs in one exposure,which can meet the clinical requirement,and improve the detection efficiency of X-ray.

Simply relying on the introduction of online teaching resources on the platforms such as Chinese University Massive Open Online Course (MOOC) to carry out online teaching, it is easy to encounter problems that the teaching resources are inconsistent with the learning situation and teaching syllabus of the students majoring in medical statistics of Binzhou Medical University, the lack of interaction among students, and the untimely teaching feedback. Therefore, on the basis of integrating the MOOC resources, we established asynchronous small private online course (SPOC) online curriculum resources for medical statistics that were suitable for the students of our school. The blended teaching mode of "SPOC+QQ living broadcast" was carried out. Before and after the implementation, two rounds of questionnaires were conducted to understand students' teaching and learning needs and teaching effect evaluation of online teaching, and then the teaching mode was optimized. The results show that the blended teaching mode of "SPOC + QQ living broadcast" designed in this study has the advantages of rich teaching resources, high enthusiasm of students, flexible teaching interaction, timely teaching feedback, and diversified teaching evaluation, which provides a reference for the better development of online and offline blended teaching reform in the future.

Objective:To report the sampling study design and radiography protocol of a large-sample investigation on skeletal maturation of 3 to 18-year-old children in China.Methods:Multi-stage stratified random sampling was employed in this study. Two provinces, municipalities, or autonomous regions were randomly selected from each of the seven regions of China, including Northeast China, Northwest China, North China, Central China, East China, Southwest China, and South China. Then one rural and one urban investigation site were randomly selected from each province, municipality, or autonomous region. In total 28 sites were included. Among those sites, four residential districts were randomly selected from each urban site, and four townships from each rural site. For each residential district or township, 1-4 kindergartens, primary schools, and middle schools were chosen. Random cluster sampling was used to extract 3-<6-year-old children in kindergartens, and 6-18-year-old children in primary schools and middle schools. The investigation on skeletal maturation was sampled proportionate to the sampling of the whole study. The estimated simple size was 780 for each site, and 21 840 for all 28 sites in total. There were six groups of 3-<6-year-old children classified at 0.5-year intervals, and 12 groups of 6-18-year-old children classified at 1-year intervals. Posteroanterior position radiography of the left hand and wrist was achieved for all subjects.Results:The study was performed from August 26, 2019 to October 16, 2021. In total, 20 444 children received posteroanterior position radiography of the left hand and wrist, including 10 196 males and 10 248 females, 9 711 urban and 10 733 rural, respectively. The 3-<6-year-old group included 1 611 (male 819, female 792) subjects, and the 6 to 18-year-old group included 18 833 (male 9 377, female 9 456) subjects.Conclusion:This nationwide investigation on skeletal maturation of 3 to 18-year-old children in seven regions of China was successfully preformed. The results of this study can provide an important reference for establishing the current evaluation criteria of bone age in Chinese children and adolescents.

Objective:To evaluate the applicability of bone age (BA) assessment methods and to investigate the difference between BA and chronological age (CA) based on the data of children in rural areas of Beijing.Methods:A total of 412 healthy children (226 boys, 186 girls) with the age 8.6 (6.8, 10.3) years old were included in this study. The data of the prospective study were from a subgroup of the project "National Nutrition and Health Systematic Survey for 0-18 Years Old Children in China", which included children with age of 3-12 years old in Beijing rural areas. The non-dominant hand-wrist radiographs of all participants were obtained in April 2021. The Dr.Wise BA detection and analysis system was used to assess the BA according to the Tanner Whitehouse 3 (TW3) radius-ulna-short bone score (TW3-RUS), TW3 carpal bone score (TW3-Carpal), China-05 TW3-Chinese RUS (TW3-C RUS), China-05 TW3-Chinese carpal (TW3-C Carpal), and Greulich-Pyle (G-P) standards. The cases were stratified by the sex and different CA in the statistical analysis. The estimated BA obtained using different methods were compared with the CA using Wilcoxon signed ranks test.Results:The sex-stratified results showed that no significant difference was found between the estimated BA using G-P standards and CA in boys ( Z=-0.694, P=0.488), while all the other estimated BA results were statistically significantly higher than CA ( P<0.05). Stratified by both sex and CA, the estimated BA using G-P standards in 4-6 years old boy groups, as well as the estimated BA using TW3-Carpal and TW3-C Carpal standards in 11-12 years old girl groups were lower than CA, while in the other groups, the estimated BA were higher than CA. Conclusions:There were varying degrees of deviations in the BA estimations using TW3, China 05, and G-P methods for children in rural areas of Beijing. It is imperative to establish a new standard for the BA evaluation of the contemporary Chinese children.

Cell Line, Tumor ; Cell Proliferation ; Humans ; Melanins ; Melanoma ; Particulate Matter

Clinical data of 5 patients with pancreatic and liver lesions who underwent endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) in the Department of Gastroenterology of Beijing Friendship Hospital from February to May 2020 were analyzed retrospectively. Pancreatic lesions were located in the head of pancreas in 3 cases, the neck of pancreas in 1 case and the body of pancreas in 1 case, with the maximum diameter of 3.2-4.6 cm. The histological and cytologic results of pancreas were all positive in 5 patients after 2-4 needles of aspiration. Three patients had single lesion in left lobe of liver, 1 had multiple lesions in left lobe of liver, and 1 had multiple lesions in left and right lobe of liver. The maximum diameter of liver lesions were 0.4-1.2 cm. After 1-3 needles of aspiration, the histological and (or) cytologic results of liver were positive in 4 of 5 patients, only 1 patient's cytologic result was negative. No associated complications were recorded. EUS-FNA for pancreatic and liver lesions is safe and effective.

Objective:To evaluate the efficacy and safety of SPOT (GI Supply, USA), a new carbon-based permanent marker approved by the Food and Drug Administration (FDA), in the endoscopic marking for gastrointestinal lesions.Methods:A total of 115 patients with gastrointestinal lesions who underwent endoscopic treatment or surgery in Beijing Friendship Hospital or Beijing Chao-Yang Hospital from April 2019 to November 2019 were enrolled in the study. SPOT was used to mark the lesions, and marking points were found during endoscopic treatment or surgery to calculate the effective marking rate by single-group target value method. Adverse events after marking were recorded, and the changes of blood routine test, liver and kidney functions before and after marking were compared.Results:The effective rate of endoscopic marking with SPOT was 99.13% (114/115). The longest marking time was 57 days. There was no puncture of intestinal wall or injection into abdominal cavity during the marking process. One patient developed mild fever after marking. The incidence of adverse events was 23.48% (27/115), which were all unrelated to the test equipment. There was no significant difference in blood routine tests or liver and kidney functions before and after marking ( P>0.05). Conclusion:SPOT produced by GI Supply can effectively mark gastrointestinal lesions without serious adverse events, which meets the requirements of clinical use.

Objective: To explore the prevalence and related factors of depressive symptoms in Chinese college students before and after the COVID-19 epidemic and to provide a reference for mental health education and management. Methods: Database of PubMed, Cochrane, CBM, WanFang, CNKI and CIP were searched for the studies on depressive symptoms in Chinese college students using the Self Rating Depression Scale (SDS) or the Center for Epidemiologic Studies Depression Scale (CES-D). All the literatures were classified according to the publication time before and after the epidemic around January 2020. Meta analysis was performed by using Stata15.1. Results: There were 26 articles before the epidemic, with a total sample size of 76 816 participants, and 18 articles after the epidemic, with a total sample size of 102 653 participants . The detection rate of depressive symptoms in college students after the epidemic was higher than that before the epidemic (35.7%, 30.9%). Fifteen factors were included in the Meta analysis. There was a positive correlation between being third year in college and college students before the epidemic ( OR = 1.27 ). Before and after the epidemic, being fourth year in college，introvert personality，breakfast skipping，physically unhealthy，poor family economy，single parent，staying up late and poor sleep quality were all positively correlated with depression of college students ( OR =1.44，1.35；1.68，2.01；3.33，3.03；2.21，4.99；1.80，1.89；2.33，1.92；1.53，3.08；2.23，2.97), while high social support and physical exercise were negatively correlated with depression for depressive symptoms in college students( OR =0.57,0.55; 0.78, 0.60 )（ P ＜0.05）. Conclusion The detection rate of depressive symptoms among college students after the epidemic is higher. The effect of introversion, physical exercise, physically unhealthy, poor sleep quality and staying up late are higher after pandemic compared than before the epidemic. The targeted mental intervention and health education should be strengthened.

Huge improvement has been made in the diagnosis and treatment of endoscopic ultrasonography (EUS) and more doctors have begun to focus on this subject with the increased level of EUS. Beijing Friendship Hospital has built a comprehensive system for the teaching method and process which include basic information screening of trainee and standardized training of perceiving and operating ability. There were 3 grades training of computer simulation, animal simulation and operation on real patients. During the first month of training, trainees accepted training with computer simulator for at least 100 hours, and underwent animal simulator during the second month, then underwent EUS on the real patients under supervision of instructors during the third month. By doing this, residents can master the technique of treatment and diagnosis of EUS in a safer and better way.

Objective:To evaluate the effect of adductor canal block(ACB)and local infiltration anesthesia(LIA)around the knee joint on inflammatory responses in the patients undergoing total knee arthroplasty(TKA).Methods:Sixty American Society of Anesthesiologists physical status Ⅱor Ⅲ patients of both sexes, aged 54-76 yr, scheduled for elective TKA, were divided into 2 groups ( n=30 each) using a random number table method: ACB group (group A) and ACB combined with LIA around knee joint group (group AL). ACB was performed with 0.5% ropivacaine 15 ml after endotracheal intubation in group A and group AL, and in addition LIA was performed around the knee joint after the osteotomy was completed during surgery in group AL.The patient-controlled ACB analgesia was applied at the end of surgery in both groups.The analgesic solution contained ropivacaine 400 ml (in 0.9% normal saline 200 ml), and the analgesic pump was set up to deliver a 5 ml bolus dose with a 30-min lockout interval and background infusion at 5 ml/h.When visual analog scale score>4, and pain was still not relived at 30 min after pressing by patients, pethidine hydrochloride 100 mg was intramuscularly injected as rescue analgesic.Peripheral venous blood samples were collected immediately before surgery (T 0) and at 24, 48 and 72 h after surgery (T 1-3) for determination of serum interleukin-6 (IL-6) and IL-10 concentrations by enzyme-linked immunosorbent assay.The muscle strength on the affected side was assessed at T 1-3.The patients′ satisfaction score, requirement for rescue analgesia, and adverse effects were recorded. Results:Compare with group A, the serum IL-6 concentrations were significantly decreased and serum IL-10 concentrations were increased at each time point after surgery, postoperative patients′ satisfaction scores were increased, the requirement for rescue analgesia was decreased ( P<0.05), and no significant change was found in the quadriceps strength of the affected limb and incidence of adverse reactions after surgery in group AL ( P>0.05). Conclusion:ACB and LIA around the knee joint can mitigate postoperative inflammatory responses in the patients undergoing TKA.