Objective To analyze the scanning parameters and radiation dose characteristics of pediatric CT examinations in Jiangxi Province, China, and to provide a basis for optimizing radiation protection in children. Methods The data of 1021 CT scans in children aged 0-15 years were collected from seven hospitals in Jiangxi Province, including one provincial hospital, four municipal hospitals, and two county-level hospitals. The data consisted of 405 head scans, 352 chest scans, and 264 abdominal scans. The scanning parameters kV, mAs, and scan length as well as the dose metrics weighted CT dose index and dose length product (DLP) were analyzed. Differences across age groups, anatomical regions, and hospitals were compared using one-way analysis of variance, and the results were compared with domestic and foreign studies. Results There were significant differences in scanning parameters and radiation doses among children of different age groups in CT examinations, and the differences between hospitals were also significant. The chest mAs and DLP in Hospital E were significantly higher than those in Hospital A, and the abdominal DLP in Hospital D was 4.3 times that of Hospital A. Compared with domestic and foreign studies, the DLP values of various anatomical regions in the < 1 year group were generally higher in the present study. The abdominal DLP in the < 1 year group (232.4 mGy·cm) was 3.3 times that in Tianjin. The head DLP in the 1-5 year group was higher than those in Germany and the United States. The chest DLP of the 11-15 year group was higher than that in Germany but lower than that in Henan Province. Conclusion There are significant differences in radiation doses received by children during CT examination in Jiangxi Province by age, anatomical region, and hospital, with some metrics exceeding domestic and international levels. Recommendations include optimizing scanning parameters (e.g., reducing mA/kV and adopting automatic exposure control technology), standardizing scan ranges, and establishing local diagnostic reference levels to mitigate radiation risks.

Objective To study mechanical properties of polyethylene terephthalate (PET)-based textile valves woven with nickel-titanium (NiTi) wires by finite element method, and combined with in vitro hemodynamic testing, to analyze the effect of wire quantity and woven position on hemodynamic performance of PET textile valve. Methods The three-dimensional (3D) geometric models of PET valves without wires and models of PET valves with wires by different numbers and distributions in radial direction were constructed using modeling software. Material properties of PET valves and wires were given based on the literature and experimental data. The transvalvular pressure difference curves of PET valves obtained from in vitro pulsatile flow experiments were used as boundary conditions. Stress distributions of the valve during peak systole and diastole were studied by finite element analysis software. Hydrodynamic performance of the valve with wires was evaluated by in vitro pulsatile flow experiments. ResultsThe finite element analysis results showed that the radially woven NiTi wires could enhance support for the PET textile valve, and support force and area of the valve in belly region of the valve leaflet with evenly distributed metal wires increased with the number of metal wires. The situation of support force was similar for silk distributions on both sides of the belly. The weaving of wires reduced stress concentration on the PET textile valve to a certain extent. The pulsatile flow experiment results showed that the stability of opening and closing shapes, effective opening area (EOA), regurgitation fraction (RF) and transvalvular pressure differences for two kinds of the PET valves with woven wires were better than those of the PET valves without wires. Conclusions Weaving metal wires in radial direction of the PET textile valve can effectively reduce stress concentrations on the PET textile valve during the cardiac cycle, and reduce tearing possibility of the valve leaflet. The woven metal wires can improve opening and closing stability of PET textile valve in in vitro hydrodynamic test, increase EOA and reduce RF and transvalvular pressure difference of the PET valve.

Objective:To investigate the expression of miRNA-34b (miR-34b) in non-small cell lung cancer (NSCLC) tissues and its effect on proliferation and invasion of human NSCLC A549 cells in vitro.Methods:The specimens of cancer tissues and paracancerous normal epithelial tissues (more than 5 cm from the edge of the tumor) were collected from 40 NSCLC patients in Shanxi Province Cancer Hospital from June 2015 to March 2017. A549 cells were transfected with miR-34b mimics (experimental group) and irrelevant sequences (negative control group), respectively. The expression of miR-34b in tissues and each group of A549 cells was detected by reverse transcription real-time fluorescence quantitative polymerase chain reaction (qRT-PCR). The proliferation activity of A549 cells in the experimental group and the negative control group was detected by methyl thiazolyl tetrazolium (MTT) assay, and the invasion ability of A549 cells in the two groups was detected by Transwell assay.Results:The relative expression of miR-34b in NSCLC tissues was lower than that in paracancerous normal epithelial tissues (0.52±0.06 vs. 1.05±0.17), and the difference was statistically significant ( P < 0.001). The relative expression of miR-34b in A549 cells of the experimental group was higher than that in the negative control group, and the difference was statistically significant ( P < 0.05). MTT assay showed that the cell proliferation ability (absorbance value) of A549 cells in the experimental group was lower than that in the negative control group after cultured for 24 and 48 hours (both P < 0.01). Transwell assay showed that the number of invaded A549 cells in the experimental group was less than that in the negative control group [(49.53±5.03) cells vs. (121.00±12.06) cells, P < 0.01]. Conclusions:The expression of miR-34b is low in NSCLC tissues, and the up-regulation of miR-34b expression can inhibit the proliferation and invasion of NSCLC A549 cells.

Objective:To investigate the association of FAT atypical cadherin 1 (FAT1) with clinicopathological parameters and prognosis in esophageal squamous cell carcinoma (ESCC).Methods:The retrospective cohort study was conducted. The clinicopathological data of 124 patients with ESCC who were admitted to Shanxi Cancer Hospital from January 2011 to December 2015 were collected. There were 85 males and 39 females, aged from 40 to 72 years, with a median age of 60 years. The ESCC tissues surgically removed and adjacent tissues specimens were collected to prepare tissue microarray for immunohistochemical staining. The 5 cases of ESCC tissues and adjacent tissues were analyzed by real-time quantitative polymerase chain reaction (qRT-PCR). Observation indicators: (1) the expression of FAT1 protein in ESCC and adjacent tissues; (2) the expression of FAT1 RNA in ESCC and adjacent tissues; (3) the expression of FAT1 protein in ESCC tissues and its association with clinicopathological parameters; (4) follow-up and survival. Follow-up using outpatient examination and telephone interview was conducted to detect survival of patients up to February 13, 2019. The survival time was from surgical date to tumor-related death or endpoint of follow-up. Measurement data with normal distribution were represented as Mean± SD, and comparison between groups was analyzed using the t test. Measurement data with skewed distribution were represented as M (range). Count data were described as absolute numbers or percentages, and comparison between groups was analyzed using the chi-square test. Comparison of ordinal data was analyzed using the non parameter rank sum test. The Kaplan-Meier method was used to calculate survival time, and Log-rank test was used for survival analysis. Results:(1) The expression of FAT1 protein in ESCC and adjacent tissues: of 124 specimens, the 107 cases of ESCC tissues and 93 cases of adjacent tissues were finally obtained because of exfoliative tissues. There were 76 cases of ESCC tissues and corresponding adjacent tissues matched. Results of immuno-histochemical staining showed that FAT1 protein was expressed in both ESCC and adjacent tissues and was brown after staining. FAT1 was located in cytomembrane, with high expression of FAT1 as ≥75 and low expression as <75. The relative expression levels of FAT1 protein in ESCC and adjacent tissues were 68±42 and 77±37, showing a significant difference between ESCC and adjacent tissues ( t=2.380, P<0.05). (2) The expression of FAT1 RNA in ESCC and adjacent tissues: results of qRT-PCR showed that the relative expression levels of FAT1 RNA in 5 cases of ESCC and adjacent tissues were 1.6±0.4 and 2.5±0.3, with a significant difference between them ( t=3.560, P<0.05). (3) The expression of FAT1 protein in ESCC tissues and its association with clinicopathological parameters: of the 107 ESCC patients, 58 cases had high expression of FAT1. There were 42 and 16 cases with high expression of FAT1 in 65 non-drinking patients and 42 drinking patients, respectively, showing a significant difference between them ( χ2=7.229, P<0.05). (4) Follow-up and survival: 96 of 107 ESCC patients were followed up for 38.0?94.9 months, with a median follow-up time of 45.9 months. Survival analysis showed that the survival time of patients with high FAT1 expression was 24 months, versus 22 months of patients with low FAT1 expression, indicating no significant difference between them ( χ2=1.773, P>0.05). Results of subgroup analysis showed that the survival time was 24 months and 21 months of female patients with high and low FAT1 expression, 23 months and 22 months of non-smoking patients with high FAT1 expression and low FAT1 expression, 23 months and 21 months of non-drinking patients with high FAT1 expression and low FAT1 expression, respectively, showing significant differences between them ( χ2=8.769, 12.827, 10.724, P<0.05). Conclusions:The expression of FAT1 in ESCC tissues is low. Female, non-smoking and non-drinking ESCC patients with high FAT1 expression have good survival.

Objective:To investigate the effectiveness and advantage of visual laryngoscope in the treatment of patients with sudden cardiac arrest who need spontaneous respiration tracheal intubation.Methods:Totally 60 patients who suffered from cardiac arrest and needed spontaneous respiration tracheal intubation were enrolled from June 2020 to February 2021 in the Affilicated Hospital of Chifeng University. Theywere randomlydivided into two groups-traditional laryngoscope (TL) group and visual laryngoscope (VL) group, with30 patients in each group. Then the success rate of glottis exposure, the operative time, success rate and complication rate of tracheal intubation were compared between the two groups. Subgroup assessment between the junior emergency resident doctor (A group) and the senior emergency resident doctor (B group) was conducted.Results:According to Cormack Lehan grades, the success rate of glottis exposure in VL group was higher than that in TL group ( P>0.05), and the success rate of Grade I in VL group was significant higer than that in TL group: 56.70%(17/30) vs. 30.00%(9/30), P<0.05. The trial times of successful intubation cases and the operative time of successful intubation cases were significantly less than those in TL group (1.30 vs 1.67, P = 0.049) and (56.37 s vs 67.12 s, P<0.05). In the subgroup, the one-time success rate of tracheal intubation in A-TL group was significantly lower than that in B-TL group (4/15 vs. 11/15, P<0.05), while the one-time success rate of tracheal intubation in A-VL group was 60.00%, which is lower than that in B-VL group ( P>0.05). The operative time consumed for successful intubation in A-TL group was significantly longer than that in B-TL group: 78.00 s vs. 55.57 s, P<0.05, while the operative time in A-VL group was a little longer than that in B-VL group ( P>0.05). Conclusions:Visual laryngoscope used in spontaneous respiration tracheal intubation can not only increase the success rate of glottis exposure, decrease trial times and shorten operative time of intubation, but also improve the success rate and decrease the complication rate of emergency tracheal intubation.

Objective:To evaluate the application of a 3D printed positioner for hip rotation center in total hip arthroplasty.Methods:From August 2015 to December 2017, 14 patients were treated by unilateral total hip arthroplasty at Department Ⅰ of Joint Surgery, Orthopaedics Hospital of Zhengzhou for avascular necrosis of femoral head or femoral neck fracture. They were 8 males and 6 females with an average age of 51.8 years (from 37 to 65 years). All their surgeries were assisted by a 3D printed positioner for hip rotation center. Postoperatively, the abduction and anteversion of acetabular cup and the hip rotation center were measured, the agreement between the hip rotation center of the affected side (O2) and the anatomical rotation center of the healthy side (O1) was assessed, and the function of the affected hip and complications were recorded at the last follow-up.Results:The 14 patients were followed up for an average of 18 months (from 6 to 24 months). The postoperative ordinates of O2 and O1 were respectively 19.36 mm±3.61 mm and 18.33 mm±3.41 mm while their abscissas 39.93 mm±2.97 mm and 39.99 mm±3.16 mm, indicating agreement between O2 and O1 ( P>0.05). The postoperative abduction and anteversion of the cup were within a normal range (39.3°±3.2°and 14.6°±1.2°, respectively). The last follow-up showed that their preoperative Harris hip scores (42.3±3.2) were significantly improved (94.3±4.7) ( t=2.873, P=0.002) and that 13 cases were rated as excellent and one as good. X-ray follow-up showed good position of their acetabular prostheses, no loosening of the cups or femoral prostheses, and no heterotopic ossification. Conclusion:A 3D printed positioner for hip rotation center can effectively assist reconstruction of the hip rotation center and accurate implantation of acetabular prosthesis in total hip arthroplasty.

Objective:To evaluate the application of 3D printed osteotomy template in total knee arthroplasty (TKA) for valgus knee.Methods:A retrospective analysis was performed of the 21 patients with valgus knee who had undergone TKA at Department Ⅰ of Joint Surgery, Orthopaedics Hospital of Zhengzhou from March 2016 to February 2018. They were 5 males and 16 females, aged from 62 to 78 years (average, 66.7 years). TKA was performed with the assistance of a 3D printed personalized osteotomy template for each patient. The efficacy of the personalized osteotomy templates was evaluated by comparing the femorotibial angle, knee range of motion, Hospital for Special Surgery (HSS) knee scores of the patients between preoperation and postoperation.Results:The 21 patients were followed up for a mean duration of 16.3 months(range, from 10 months to 4 years). All incisions healed by the first intention. The last follow-ups showed that their preoperative femorotibial angle 17.6°±5.7° was improved significantly to 6.3°±1.2°, their preoperative knee range of motion 71.3°±5.8° increased significantly to 102.4°±7.5°, and their preoperative HSS scores 38.2±5.7 increased significantly to 87.5±3.5 ( P<0.001). Their radiographic evaluation at the last follow-up showed stable prosthetic components with no implant loosing or osteolysis. Conclusion:A personalized 3D printed osteotomy template can be used in TKA for valgus knee, leading to accurate osteotomy, effective correction of mechanical alignment and satisfactory clinical outcomes.

Objective To investigate the status and analyze the influencing factors of structural empowerment and psychological empowerment of midwives in Suzhou.Methods Using convenience sampling,totally 309 midwives from fifteen hospitals in Suzhou were investigated with the Conditions of Work Effectiveness Questionnaire-Ⅱ (CWEQ-Ⅱ) and Psychological Empowerment Scale (PES).Results The scores of structural and psychological empowerment of midwives were (18.07±3.12) and (14.82±2.01).There was a significantly positive correlation between midwives' structural and psychological empowerment (r=0.396,P＜0.01).Hospital level and whether participate in midwifery standardization training had an impact on structural empowerment score(P＜0.05).Age,parental status,job title,salary,delivery room working hours,number of night shifts per month,and whether or not participate in teaching had an impact on psychological empowerment score(P＜0.05).Conclusion Midwives' structural and psychological empowerments are at a moderate level.Administrators should take targeted intervention to create an empowerment-allowing working environment for midwives,stabilize midwives work force,strengthen midwifery discipline construction and make full specialized features of midwives.

OBJECTIVETo explore the relationship between the time after thrombosis and the efficacy of combined ultrasound and microbubble treatment for rescuing the ischemic tissues.

METHODSRat models of thrombosis in the right common iliac artery were established and received combined ultrasound and microbubble treatment at 3, 6 and 12 h after thrombosis. The recanalization rate of the right common iliac artery was assessed using both 2-dimensional and Doppler ultrasound. The plateau acoustic intensity (AI) was quantified for estimating the skeletal microvascular blood volume, and skeletal muscle injury markers including myoglobin (Mb) and creatinine kinase (CK) were measured using ELISA. Postmortem TUNEL staining was used to detect the apoptotic rate of skeletal muscle cells in the hind limb of the rats.

RESULTSCompared with those in 3 h group, the recanalization rate and AI were significantly lower, and the levels of Mb and CK and the apoptotic rate of the skeletal muscle cells were significantly higher in both 6 h group and 12 h group ( < 0.05). Compared with those in 6 h group, the rats receiving treatment at 12 h after thrombosis showed significantly lowered AI and increased Mb, CK and apoptotic rate of the skeletal muscle cells ( < 0.05).

CONCLUSIONSThe efficacy of combined ultrasound and microbubble treatment for rescuing ischemic tissues tends to be attenuated as the time after thrombosis prolongs in rats.

Objective To develop the maternity nurse competency model,and provide references for nurse selection,training and evaluation of "family-centered" and maternal care model. MethodsUsing competency theory,and based on semi-structured interviews and "family-centered" maternal care model,the indicators of maternity nurse competency was shaped. By using Delphi method,seven experts from maternal care and management field were inquired to develop the maternity nurse competency.Results Maternity nurse competency model based on "family-centered" maternal care model included 4 dimensions such as nursing knowledge,nursing ability,intervention capability of family-centered obstetric care specialist,personal attitudes and traits,totally 29 indicators of behavioral competency. This model had expert representation and high reliability.Conclusions The maternity nurse competency model based on "family-centered" maternal care model are scientific and reliable,and it can be used as the reference standard of nurses' selection,training and assessment in "family-centered" maternal care model.