Objective:To investigate the effect of the Ilizarov technique in the treatment of post-traumatic lower extremity shortening with talipes equinovarus.Methods:Clinical data of patients with post-traumatic lower extremity shortening and talipes equinovarus treated by the Ilizarov technique in the Department of Orthopaedics of Xuzhou Renci Hospital from January 2013 to April 2020 were retrospectively analyzed. The annular external fixator was installed on the affected limb according to the Ilizarov principle of external fixation. 3 days after the operation, the internal and lateral screw rods were adjusted at the speed of 2 mm/d to gradually correct the talipes equinovarus. 7 days after surgery, the lower leg was lengthened at a speed of 1 mm/d. After the foot was corrected, the foot external fixator was continued to be worn for 4 to 6 weeks, and then the fixator was removed and the foot was immobilized with a brace for 6 to 8 weeks. The lower leg fixator was removed after the lower extremity length was restored and the bone mineralization at the extension site was good. The length of both lower extremities, angle of talonavicular joint, angle of plantar flexion and dorsal extension of the ankle, and range of motion of ankle were compared before surgery and at the last follow-up. At the last follow-up, the affected feet were scored and rated using the International Clubfoot Study Group (ICFSG) scoring system, which was divided into four grades: excellent, good, medium, and poor. SPSS 25.0 software was used for statistical analysis, and each measurement index and ICFSG score were expressed in Mean±SD. Paired t-test was used to compare the preoperative and last follow-up data, and P<0.05 was considered statistically significant. Results:A total of 31 patients were enrolled, including 17 males and 14 females. The age was 15-18 years old, with an average of 16.5 years old. There were 16 cases on the right side and 15 cases on the left side. The lower extremity shortening was 45-75 mm, with an average of 65 mm. The fixation time of the external fixator was 4.5-6 months after surgery, with an average of 5 months, and the follow-up time was 22-28 months, with an average of 25.5 months. The length of the affected lower extremity recovered, the shape was basically satisfactory, and the plantar gait was restored. At the last follow-up, compared with the preoperative period, the anteroposterior talocalcaneal angle of the foot (23.0°±2.1° vs. 8.5°±2.6°), from lateral talocalcaneal angle the foot (27.0°±4.3° vs. 11.2°±4.4°), ankle plantar flexion angle (24.5°±6.8° vs. 51.1°±6.5°), ankle dorsiflexion angle (5.8°±3.5° vs. -46.8°±7.0°) and ankle range of motion (30.3°±8.2° vs. 4.2°±1.6°) were statistically significant ( P <0.01). ICFSG score: The points at the last follow-up (8.0 ± 4.2) were significantly lower than that before the operation (41.9 ± 5.3) ( P<0.01), of which 18 were excellent, 9 were good, and 4 were medium. Two cases had recurrent deformities in the later stage, and the results were satisfactory after the fusion of the talonavicular joint and calcaneocuboid joint and the anteposition of the posterior tibial tendon in the second stage. There were 4 cases of toe contracture deformity, which did not recur after the release of the flexor digitorum longus tendon at the toe. Anterior ankle impingement was observed in 5 cases and improved after the arthroscopic osteophyte removal. After the lower extremity extension was in place, the external fixator was replaced by the intramedullary nail for walking in 6 patients. The infection of the nail path occurred in 7 cases, which improved after replacement of fixing pins and dressing change of the nail path. Conclusion:The application of the Ilizarov technique in the treatment of post-traumatic lower extremity shortening with talipes equinovarus has the advantages of small trauma and dynamic control of deformity correction, which can achieve good result.

Objective:To investigate the effect of the Ilizarov technique in the treatment of post-traumatic lower extremity shortening with talipes equinovarus.Methods:Clinical data of patients with post-traumatic lower extremity shortening and talipes equinovarus treated by the Ilizarov technique in the Department of Orthopaedics of Xuzhou Renci Hospital from January 2013 to April 2020 were retrospectively analyzed. The annular external fixator was installed on the affected limb according to the Ilizarov principle of external fixation. 3 days after the operation, the internal and lateral screw rods were adjusted at the speed of 2 mm/d to gradually correct the talipes equinovarus. 7 days after surgery, the lower leg was lengthened at a speed of 1 mm/d. After the foot was corrected, the foot external fixator was continued to be worn for 4 to 6 weeks, and then the fixator was removed and the foot was immobilized with a brace for 6 to 8 weeks. The lower leg fixator was removed after the lower extremity length was restored and the bone mineralization at the extension site was good. The length of both lower extremities, angle of talonavicular joint, angle of plantar flexion and dorsal extension of the ankle, and range of motion of ankle were compared before surgery and at the last follow-up. At the last follow-up, the affected feet were scored and rated using the International Clubfoot Study Group (ICFSG) scoring system, which was divided into four grades: excellent, good, medium, and poor. SPSS 25.0 software was used for statistical analysis, and each measurement index and ICFSG score were expressed in Mean±SD. Paired t-test was used to compare the preoperative and last follow-up data, and P<0.05 was considered statistically significant. Results:A total of 31 patients were enrolled, including 17 males and 14 females. The age was 15-18 years old, with an average of 16.5 years old. There were 16 cases on the right side and 15 cases on the left side. The lower extremity shortening was 45-75 mm, with an average of 65 mm. The fixation time of the external fixator was 4.5-6 months after surgery, with an average of 5 months, and the follow-up time was 22-28 months, with an average of 25.5 months. The length of the affected lower extremity recovered, the shape was basically satisfactory, and the plantar gait was restored. At the last follow-up, compared with the preoperative period, the anteroposterior talocalcaneal angle of the foot (23.0°±2.1° vs. 8.5°±2.6°), from lateral talocalcaneal angle the foot (27.0°±4.3° vs. 11.2°±4.4°), ankle plantar flexion angle (24.5°±6.8° vs. 51.1°±6.5°), ankle dorsiflexion angle (5.8°±3.5° vs. -46.8°±7.0°) and ankle range of motion (30.3°±8.2° vs. 4.2°±1.6°) were statistically significant ( P <0.01). ICFSG score: The points at the last follow-up (8.0 ± 4.2) were significantly lower than that before the operation (41.9 ± 5.3) ( P<0.01), of which 18 were excellent, 9 were good, and 4 were medium. Two cases had recurrent deformities in the later stage, and the results were satisfactory after the fusion of the talonavicular joint and calcaneocuboid joint and the anteposition of the posterior tibial tendon in the second stage. There were 4 cases of toe contracture deformity, which did not recur after the release of the flexor digitorum longus tendon at the toe. Anterior ankle impingement was observed in 5 cases and improved after the arthroscopic osteophyte removal. After the lower extremity extension was in place, the external fixator was replaced by the intramedullary nail for walking in 6 patients. The infection of the nail path occurred in 7 cases, which improved after replacement of fixing pins and dressing change of the nail path. Conclusion:The application of the Ilizarov technique in the treatment of post-traumatic lower extremity shortening with talipes equinovarus has the advantages of small trauma and dynamic control of deformity correction, which can achieve good result.

Objective: To investigate the feasibility of cine three-dimensional (3D) balanced steady-state free precession (b-SSFP) imaging combined with a non-local means (NLM) algorithm for image denoising in evaluating cardiac function in children with repaired tetralogy of Fallot (rTOF). Materials and Methods: Thirty-five patients with rTOF (mean age, 12 years; range, 7–18 years) were enrolled to undergo cardiac cine image acquisition, including two-dimensional (2D) b-SSFP, 3D b-SSFP, and 3D b-SSFP combined with NLM. End-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), and ejection fraction (EF) of the two ventricles were measured and indexed by body surface index. Acquisition time and image quality were recorded and compared among the three imaging sequences. Results: 3D b-SSFP with denoising vs. 2D b-SSFP had high correlation coefficients for EDV, ESV, SV, and EF of the left (0.959– 0.991; p < 0.001) as well as right (0.755–0.965; p < 0.001) ventricular metrics. The image acquisition time ± standard deviation (SD) was 25.1 ± 2.4 seconds for 3D b-SSFP compared with 277.6 ± 0.7 seconds for 2D b-SSFP, indicating a significantly shorter time with the 3D than the 2D sequence (p < 0.001). Image quality score was better with 3D b-SSFP combined with denoising than with 3D b-SSFP (mean ± SD, 3.8 ± 0.6 vs. 3.5 ± 0.6; p = 0.005). Signal-to-noise ratios for blood and myocardium as well as contrast between blood and myocardium were higher for 3D b-SSFP combined with denoising than for 3D b-SSFP (p < 0.05 for all but septal myocardium). Conclusion The 3D b-SSFP sequence can significantly reduce acquisition time compared to the 2D b-SSFP sequence for cine imaging in the evaluation of ventricular function in children with rTOF, and its quality can be further improved by combining it with an NLM denoising method.

Objective: To investigate the feasibility of cine three-dimensional (3D) balanced steady-state free precession (b-SSFP) imaging combined with a non-local means (NLM) algorithm for image denoising in evaluating cardiac function in children with repaired tetralogy of Fallot (rTOF). Materials and Methods: Thirty-five patients with rTOF (mean age, 12 years; range, 7–18 years) were enrolled to undergo cardiac cine image acquisition, including two-dimensional (2D) b-SSFP, 3D b-SSFP, and 3D b-SSFP combined with NLM. End-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), and ejection fraction (EF) of the two ventricles were measured and indexed by body surface index. Acquisition time and image quality were recorded and compared among the three imaging sequences. Results: 3D b-SSFP with denoising vs. 2D b-SSFP had high correlation coefficients for EDV, ESV, SV, and EF of the left (0.959– 0.991; p < 0.001) as well as right (0.755–0.965; p < 0.001) ventricular metrics. The image acquisition time ± standard deviation (SD) was 25.1 ± 2.4 seconds for 3D b-SSFP compared with 277.6 ± 0.7 seconds for 2D b-SSFP, indicating a significantly shorter time with the 3D than the 2D sequence (p < 0.001). Image quality score was better with 3D b-SSFP combined with denoising than with 3D b-SSFP (mean ± SD, 3.8 ± 0.6 vs. 3.5 ± 0.6; p = 0.005). Signal-to-noise ratios for blood and myocardium as well as contrast between blood and myocardium were higher for 3D b-SSFP combined with denoising than for 3D b-SSFP (p < 0.05 for all but septal myocardium). Conclusion The 3D b-SSFP sequence can significantly reduce acquisition time compared to the 2D b-SSFP sequence for cine imaging in the evaluation of ventricular function in children with rTOF, and its quality can be further improved by combining it with an NLM denoising method.

Objective:To develop a prototype artificial intelligence image recognition system for detecting dental caries, especially those without cavities, in children.Methods:Seven hundred and twelve intraoral photos, which were taken by dental professionals using a digital camera from October 2013 to June 2020 in the Department of Pediatric Dentistry, Peking University School and Hospital of Stomatology, were collected from the children who received dental treatment under general anesthesia. The well-documented post-treatment electronic dental record of each child was identified as label standard to determine whether the teeth were carious and the type of caries types such as caries that had become cavities (caries with cavities), pit and fissure caries that had not become cavities (pit and fissure caries) and proximal caries which the marginal ridge enamel had not been destroyed (proximal caries). The various teeth and caries types were labeled by pediatric dentists using VoTT software (Windows 2.1.0, Microsoft, U S A). There were five labeled groups: pit and fissure caries, approximal caries, non-carious approximal surfaces, caries with cavities and teeth without caries (including intact fillings). Each group was randomly divided into training dataset, validation dataset and test dataset at a ratio of 6.4∶1.6∶2.0 by using random number table. After using the labeled training dataset for deep learning training, a deep learning-based artificial intelligence (AI) image recognition system for detecting dental caries was established, with the caries probability greater than 50.0% as the criterion for determining caries. Sensitivity and accuracy were used as indicators of recognition specificity.Results:Seven hundred and twelve single-jaw intraoral photographs were segmented and annotated into 953 pit and fissure caries, 1 002 approximal caries, 3 008 caries with cavities, 3 189 teeth without caries and 862 non-carious approximal surfaces, totaly 9 014 labels. The sensitivities and specificities of the test set were 96.0% and 97.0% for caries with cavities, 95.8% and 99.0% for pit and fissure caries and 88.1% and 97.1% for approximal caries.Conclusions:The current AI system developed based on deep learning of the intra-oral photos in the present study showed the ability to detect dental caries. Furthermore, the AI system could accurately verify different types of dental caries such as caries with cavities, pit and fissure caries and proximal caries.

OBJECTIVE：To provide reference for improving the quality standard of Rhizoma Bego niae from Guizhou . METHODS：Five batches of Rhizoma Begoniae from Guizhou were collected ，and the microscopic characteri stics of the Rhizoma Begoniae powder were observed. According to the corresponding methods in 2015 edition of Chinese Pharmacopoeia （part Ⅳ）， potent adenosine 50-triphosphate competitive phosphati - dylinositol-3-kinase/mammalian target of rapamycin inhibitors：discovery of compound 26（PKI-587），a highly effi cacious dual inhibitor Morpholine as a privileged structure ：a review on the me - dicinal chemistry and pharmacological activity of morpho - line containing bioactive molecules[J]. Med Res Rev ， qq.com 2019. DOI ：10.1002/med.21634. qualitative identification of Rhizoma Begoniae was conducted by TLC ，and the contents of moisture ，total ash and water-soluble extract in Rhizoma Begoniae were determined. The contents of rutin were determined by HPLC. RESULTS ：The powder of Rhizoma Begoniae medicinal materials was brown ，stone cells were square ，polygonal-like or irregular. There were many starch grains and few complex grains. The conduit ，calcium oxalate square crystal/cluster crystal were visible. The same fluorescence spots were found in the same location of TLC atlas of Rhizoma Begoniae control herb. The moisture ，total ash ，water-soluble extract contents were 10.15％-11.41％，8.70％-12.59％ and 16.91％-19.58％，respectively. The linear range of rutin were 18.47-147.8 μg/mL （r＝0.999 8）；RSDs of reproducibility ，intermediate precision and stability tests （8 h）were all lower than 3.0％；the average recoveries were 99.39％-100.29％（RSDs were 0.23％-2.59％，n＝3）；the contents of rutin in 5 batches of Rhizoma Begoniae were 0.102％-0.198％. CONCLUSIONS ：The contents of moisture and total ash shall not exceed 13.0％ and 14.0％ respectively， and the contents of water-soluble extract and rutin shall not be less than 15.0％ and 0.080％. The quality standard established in this study can be used for the quality control of Rhizoma Begoniae from Guizhou.

Objective:To explore the clinical characteristics and prognostic factors of patients with special types of esophageal ulcer.Methods:The data of 53 cases of esophageal ulcer in Xiangya Hospital of Central South University from October 2014 to October 2019 were analyzed retrospectively, and the prognosis was followed up by telephone.Results:The average age of onset was (51.2±13.4)years old. 84.91% of the patients (45/53) had unknown causes. 66.67% (34/51) had symptoms of discomfort or pain in the esophageal region. 67.92% (36/53) of the ulcers involved the lower esophageal segment and 52.83% (28/53) involved the middle thoracic segment of the esophagus. The common pathological changes were chronic inflammation and squamous cell hyperplasia. Nearly 1/3 of the patients had no improvement, deterioration or recurrence after treatment. All 7 patients with T cell spot test of tuberculosis infection (TSPOT) positive and other tuberculosis infection were treated effectively.Conclusions:Special types of esophageal ulcer are common in middle-aged men, most of the patients have unknown etiology. The most common clinical symptom is the discomfort or pain in the area of esophagus. The common involved part is the lower part of esophagus. The curative effect is not good or easy to recur. Antituberculosis therapy may be effective in patients with TSPOT positive and other TB infection bases.

Objective:To evaluate the feasibility of cardiac MRI three dimensional (3D) balanced steady state free precession (b-SSFP) cine imaging in evaluating cardiac function in children with repaired tetralogy of Fallot (TOF).Methods:Thirty children with repaired TOF underwent cardiac MRI examination at Shanghai Children′s Medical Cent er Affiliated to Shanghai Jiao Tong University School of Medicine, were retrospectively collected from April 2018 to October 2019. From June 2017 to August 2018, 10 healthy children were enrolled. Cardiac images of subjects were obtained using both two dimensional (2D) b-SSFP and 3D b-SSFP cardiac cine MRI and the total acquisition time was recorded. The image quality was scored using a 5-point scale, with a score≥3 as diagnostic image quality. The left and right ventricular end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), ejection fraction (EF), cardiac output (CO), and cardiac index (CI) were measured. The left and right ventricle parameters were compared using paired ttest or Wilcoxon test. The Pearson correlation or Spearman correlation analysis were used to evluate the correlation between the parameters measured with the 2 methods. Results:The acquisition time of 2D b-SSFP images was (426.5±13.0) s, and the total time of 3D b-SSFP images was (24.7±2.5) s. The 2D b-SSFP image quality score was better than 3D b-SSFP, and the differences were statistically significant (TOF patients: Z=-3.879, P<0.001; volunteers: Z=-2.646, P=0.003). All 2D and 3D b-SSFP image quality scores were ≥ 3 points, which can be used for clinical diagnosis. There were no statistically significant differences in cardiac function parameters between two series measurements in both TOF patients and volunteers ( P>0.05). For TOF patients, the left ventricular EDV, ESV, SV, EF, CO and right ventricular EDV, ESV, and SV showed highly positive correlation ( r>0.8, P<0.05). For volunteers, the left ventricular EDV, ESV, SV and right ventricular EDV and SV showed highly positive correlation ( r>0.8, P<0.05). Conclusion:Compared with the 2D b-SSFP sequence, 3D b-SSFP sequence with fairy good image quality can meet the diagnostic requirement and can accurately measure the cardiac function with shorter acquisition time. The 3D b-SSFP has a good application prospect in pediatric cardiac MRI.

Objective: To investigate and analyze the epidemiological and clinical characteristics of some cases of coronavirus disease 2019 (COVID-19) in Beijing. Methods: A retrospective study was conducted to analyze the data of 46 patients with COVID-19 in Beijing from 20th January 2020 to 8th February 2020 at the Fifth Medical Center of the PLA General Hospital. Features of clinical symptoms, laboratory inspections and imaging inspections were analyzed. Statistical analysis used Fisher exact test. If P<0.05, post-hoc test was used for pairwise comparison, and the statistics were corrected by Bonferroni test. Results: Among the 46 patients included in this study, 27 were male and 19 were female. The age range was between 3 - 79 years old, and the mean age was (41.8 ± 16.3) years old. The average incubation period was (4.85 ± 3.00) days. A total of 26 cases (56.5%) were clustered patients, and 12 (26.1%), 23 (50.0%) and 11 patients (23.9%)were assigned to the mild group, common group, and sever group, respectively. Fever (39.8%), cough (27.6%), and fatigue (25.3%) was the main clinical symptom for these patients. The decrease in white blood cell counts occurred in 12 patients, four had the decrease in T lymphocyte counts, 17 had the decrease in CD4 ⁺ T lymphocyte counts, seven had the decrease in CD8 ⁺ T lymphocyte counts, 21 had the increase level of C-reactive protein (45.7%), and IL-6 level increased in 32 cases (69.6%), erythrocyte sedimentation rate increased in 20 cases(50.0%), serum ferritin level increased in 26 cases (56.5%), and blood lactate level increased in nine cases. There was a statistically significant difference in the number of cases in which the absolute value of T lymphocytes and of CD8 ⁺ T lymphocytes decreased among the mild, common and severe groups (all P<0.05). Comparing the number of cases in the three groups with elevated C-reactive protein, interleukin-6, erythrocyte sedimentation rate, serum ferritin and blood lactate levels, the differences were statistically significant (all P<0.05). The number of cases with elevated C-reactive protein levels was higher in severe group than that in mild and common group. The number of cases with elevated interleukin-6, erythrocyte sedimentation rate, and serum ferritin levels were higher in severe group than in mild group. The number of cases with elevated blood lactic acid levels was higher in severe group than in mild group. The differences between the above groups were statistically significant (both adjusted P<0.017). Analysis of chest X-rays showed that 34 patients (73.9%) had inflammation in the lungs. Conclusions The epidemiological characteristics of cases with COVID-19 in Beijing are mainly imported cases and clustered cases. The clinical manifestations are mainly fever , fatigue and cough. C-reactive protein, interleukin-6, red blood cell sedimentation rate, serum ferritin and blood lactate levels are higher in severe patients.

Objective:To investigate and analyze the epidemiological and clinical characteristics of 46 patients with corona virus disease 2019 (COVID-19) in Beijing City.Methods:A retrospective study was conducted to analyze the data of 46 patients with COVID-19 in Beijing from 20th January 2020 to 8th February 2020 at the Fifth Medical Center of the PLA General Hospital in Beijing City. Twelve, 23 and 11 patients were assigned to the mild group, common group and severe group, respectively. The epidemiological history, clinical characteristics, laboratory tests and imaging inspections were analyzed. Statistical analysis used Fisher exact test. If P<0.05, post- hoc test was used for pairwise comparison, and the statistics were corrected by Bonferroni test. Results:Among the 46 patients included in this study, 27 were male and 19 were female. The age range was between 3-79 years old, and the age was (41.8±16.3) years old. The average incubation period was (4.85±3.00) days. A total of 26 cases (56.5%) were clustered patients, and 26 cases had a history of staying in Wuhan, 10 cases had contact with Wuhan personnel. Fever (39 cases, 84.8%), cough (27 cases, 58.7%), and fatigue (25 cases, 54.3%) were the main clinical symptoms for these patients. The decrease in white blood cell counts occurred in 12 patients, four had the decrease in T lymphocyte percentage, 17 had the decrease in CD4 + T lymphocyte counts, seven had the decrease in CD8 + T lymphocyte counts, 21 had the increase level of C reactive protein (45.7%), and interleukin-6 (IL-6) level increased in 32 cases (69.6%), erythrocyte sedimentation rate (ESR) increased in 23 cases (50.0%), serum ferritin level increased in 26 cases (56.5%), and blood lactic acid level increased in nine cases. There were statistically significant differences in the proportion of cases with decreased absolute value of CD8 + T lymphocytes and T lymphocytes counts among the mild, common and severe groups (all P<0.05). Comparing the proportion of cases in the three groups with elevated C reactive protein, IL-6, ESR, serum ferritin and blood lactic acid levels, the differences were statistically significant (all P<0.05). The proportion of cases with elevated C reactive protein levels in severe group was higher than those in mild and common groups. The proportion of cases with elevated IL-6, ESR, and serum ferritin levels in severe and common group were higher than those in mild group. The proportion of cases with elevated blood lactic acid levels in severe group was higher than those in mild group. The differences between the above groups were statistically significant (all adjusted P<0.017). Analysis of chest X-rays results showed that 34 patients (73.9%) had inflammation in the lungs. Conclusions:The epidemiological characteristics of patients with COVID-19 in Beijing City are mainly imported cases and clustered cases. The clinical manifestations are mainly fever, fatigue and cough. C reactive protein, IL-6, ESR, serum ferritin and blood lactic acid levels are higher in severe patients.