As a non-invasive physiological indicator,electroencephalography signal provides an objective assessment of psychological stress levels among nursing staff in major public health emergencies,offering a scientific basis for targeted psychological interventions while overcoming the limitations of subjective bias inherent in traditional questionnaire-based methods.A psychological stress classification model based on bidirectional long short-term memory and attention mechanism is proposed to classify the psychological stress of clinical nurses more effectively by analyzing their electroencephalography signals.Experimental results show that the proposed model exhibits better classification performance than the traditional long short-term memory model on the DREAMER dataset,the Feeling Emotions dataset and the self-built dataset.This study provides a novel approach for assessing psychological stress,which is helpful to improve the pertinence and effectiveness of clinical nursing work.

As a non-invasive physiological indicator,electroencephalography signal provides an objective assessment of psychological stress levels among nursing staff in major public health emergencies,offering a scientific basis for targeted psychological interventions while overcoming the limitations of subjective bias inherent in traditional questionnaire-based methods.A psychological stress classification model based on bidirectional long short-term memory and attention mechanism is proposed to classify the psychological stress of clinical nurses more effectively by analyzing their electroencephalography signals.Experimental results show that the proposed model exhibits better classification performance than the traditional long short-term memory model on the DREAMER dataset,the Feeling Emotions dataset and the self-built dataset.This study provides a novel approach for assessing psychological stress,which is helpful to improve the pertinence and effectiveness of clinical nursing work.

Abstract: To investigate the status and influencing factors of tooth loss among the elderly population in China, so as to provide insights into early prevention of tooth loss. Methods: Based on the Chinese Longitudinal Healthy Longevity Survey (CLHLS), data of the elderly people aged 65 years and older who participated in the survey in 2018 were collected, including demographic information, lifestyle, dietary habits, medical history, number of teeth remaining and self-assessment indicators. The status of tooth loss among the elderly were described based on the standard of 28 teeth, and factors affecting tooth loss were analyzed using a multivariable ordinal logistic regression model. Results: A total of 5 260 people was recruited, including 3 346 males (63.61%) and 1 914 females (36.39%). The median age was 78.00 (interquartile range, 18.00) years. The median number of teeth remaining was 12.00 (interquartile range, 23.00), and the median number of missing teeth was 16.00 (interquartile range, 23.00). Multivariable ordinal logistic regression analysis showed that the elderly who were female (OR=1.270, 95%CI: 1.098-1.470), had advanced age (OR=1.090, 95%CI: 1.083-1.098), lived in rural areas (OR=1.369, 95%CI: 1.165-1.610) and urban areas (OR=1.208, 95%CI: 1.027-1.422), smoked (past, OR=1.471, 95%CI: 1.240-1.746; always, OR=1.545, 95%CI: 1.300-1.838) and brushed teeth less than once a day (OR=1.791, 95%CI: 1.488-2.160) had more missing teeth; while the elderly who had high levels of education (junior high school, OR=0.819, 95%CI: 0.681-0.972; high school, OR=0.626, 95%CI: 0.507-0.771; college and above, OR=0.468, 95%CI: 0.334-0.657), kept physical exercise (OR=0.840, 95%CI: 0.736-0.958) and were overweight/obese (OR=0.868, 95%CI: 0.769-0.980) had less missing teeth. Conclusion Gender, age, residence, educational level, smoking, physical exercise, teeth brushing frequency and overweight/obese are the influencing factors for tooth loss among the elderly in China.

Objective:To investigate the correlations between the bone mineral densities and biomechanical properties on different layers of the cancellous bone in the proximal tibia.Methods:Quantitative CT was conducted of the 15 specimens of adult male tibia. Based on the artificial destruction levels at the trabecular bone on the tibial plateau, the 15 specimens were randomly divided into 3 groups ( n=5): group A (cancellous bone on the 1.5 cm layer below the articular cartilage), group B (cancellous bone on the 3.0 cm layer under the articular cartilage) and group C (cancellous bone on the 0 to 3 cm range of the subchondral bone). After standing positions were simulated in the 3 sets of specimens, they were connected to a biomechanical testing machine. Twenty-four sites were selected and subjected to a vertical load of 600 N. Strain values and overall displacement values of the specimens were recorded before and after trabecular bone destruction. The correlations were analyzed between bone density and displacement values in groups A and B. The strain values before and after trabecular bone destruction, as well as the overall deformation values of the specimens were compared between the 3 groups. Results:The bone densities of specimens in groups A and B were negatively correlated with the displacement values before and after destruction ( P<0.05). Comparisons of strain values at the 24 sites before and after trabecular bone destruction within 3 groups: There were statistically significant differences in the strain values at 8 sites between before and after trabecular bone destruction in group A ( P<0.05). Of the 8 sites, 6 showed increased strains which were mainly concentrated around the insertion point of the anterior cruciate ligament and the medial tibial plateau. There were statistically significant differences in the strain values between before and after trabecular bone destruction at 3 sites in group B ( P<0.05). The strains at all the 3 sites increased, mainly concentrated behind the surface below the level of destruction. There were statistically significant differences in the strain values at 10 sites in group C between before and after trabecular bone destruction ( P<0.05). Of the 10 sites, 5 showed a decrease in the strain which was concentrated above the destruction plane, and 5 showed an increase in the strain which was concentrated below the destruction plane. The overall deformation values of the specimens in groups A, B, and C were (0.033±0.003) mm, (0.015±0.003) mm, and (0.066±0.007) mm, respectively, showing statistically significant differences between the 3 groups ( P<0.05) as well as between any 2 groups ( P<0.05). Conclusions:Bone mineral density in the cancellous bone of the proximal tibia has some value in assessment of the bone strength. Destruction of the proximal tibial cancellous bone can significantly change the strain distribution on the proximal tibia. The proximal cancellous bone of the tibia plays a key role in stress support and load conduction.

The abdominoperineal excision (APE) is still one of the standard operations for low rectal cancer. The exralevator APE can reduce the positive rate of circumferential margin and perforation rate of rectal cancer, but the incidence of postoperative complications is relatively high. With the continuous development of minimally invasive surgery, the transperineal minimally invasive Abdominoperineal excision (Tpm-APE) is proposed. Compared with traditional APE, the Tpm-APE has potential technical advantages, but there is a lack of large sample and multicenter clinical research evidence. The authors share the design and results of an international multicenter clinical study to investigate the clinical practice of Tpm-APE in the treatment of low rectal cancer.

Objective:To investigate the learning curve of laparoscopic transanal total mesorectal excision (taTME) for rectal cancer operated by one or two surgery teams.Methods:The retrospective cross-sectional study was conducted. Based on the concept of real-world research, the clinical data of 1 458 patients undergoing laparoscopic rectal cancer taTME from 44 medical centers who were registered in the Chinese taTME registry collaborative (CTRC) database from May 2010 to May 2020 were collected. The 1 458 patients were divided into cohorts with one surgery team or two surgery teams according to the operation method. Patients with one surgery team underwent taTME by transabdominal operation and then by transanal operation. Patients with two surgery teams underwent taTME by transabdominal and transanal operation simultaneously with duration of the simutaneous operation time ≥30 minutes. The entire surgical process of patients with two surgery teams is not required to be performed by two surgery teams simutaneously. The clinical data were collected from the medical centers with similar operation amount according to the operation time sequence to analyze the difference between different operation stages and explore the learning curve. The operation time was taken as the parameter to carry out cumulative sum analysis and draw the learning curve of laparoscopic rectal cancer taTME in each medical center. The clinicopathological characteristics of patients from two medical centers with the largest difference in learning curves were analyzed. Observation indicators: (1) screening results of clinical data; (2) clinical data collection of patients with one surgery team; (3) surgical situations of laparoscopic rectal cancer taTME from the one surgery team in different operation stages; (4) learning curve of the one surgery team; (5) clinical data collection of patients with two surgery teams; (6) surgical situations of laparoscopic rectal cancer taTME from the two surgery teams; (7) learning curve of the two surgery teams. The cumulative sum was calculated by the CUSUM=∑i=1nXi-U, where Xi represented the operation time of each taTME, U represented the average operation time of all cases, and n represented the operation number. Fitting process was conducted on scatter plot of learning curves. Taking the apex of learning curve as the boundary, the learning curve was divided into two stages. The abscissa corresponding to the apex of learning curve was the number of operations that needed to be performed to cross the learning curve. Measurement data with normal distribution were represented as Mean±SD. Comparison between two groups was conducted using the t test and comparison between multiple groups was conducted using the ANOVA. Measurement data with skewed distribution were represented as M( P25,P75), and comparison between groups was conducted using the Mann-Whitney U test. Comparison of ordinal data was analyzed using the rank sum test. Count data were analyzed using the chi-square test or Fisher exact probability. Results:(1) Screening results of clinical data:the clinical data of 661 patients from 7 medical centers with one surgery team and two surgery teams were collected. (2) Clinical data collection of patients with one surgery team: the clinical data of 312 patients undergoing laparoscopic rectal cancer taTME from 5 medical centers were collected including 42 cases in the number 2 medical center, 97 cases in the number 20 medical center, 82 cases in the number 33 medical center, 35 cases in the number 37 medical center and 56 cases in the number 39 medical center, respectively. (3) Surgical situations of laparoscopic rectal cancer taTME from the one surgery team in different operation stages: three medical centers including the number 2, number 37 and number 39 medical center with close operation volume provided the clinical data of cases distributed in five operation stages. Among the five operation stages, the proportion of high-quality operation of total mesorectal excision (TME) was ≥17/18, the incidence of postoperative complications was ≤13.3%(4/30) and the incidence of anastomotic leakage was ≤10.0%(3/30). There was no significant difference in the TME quality, postoperative complications or anastomotic leakage among the five operation stages ( P>0.05). There was no significant difference in the operation time among the five operation stages ( χ2=6.950, P>0.05). (4) Learning curve of the one surgery team: the number of operations corresponding to the turning point of learning curve in number 2 and number 20 medical center was 22 and 39, respectively. The number of operations corresponding to the turning points of learning curve in number 33 and number 37 medical center was 15, 66 and 10, 28, respectively. The number of operations corresponding to the turning point of learning curve in number 39 medical center was 20. The overall curve of number 20 medical center was in line with the trend of learning curve and 39 cases of operations was the minimum number needed to cross the learning curve. The biggest difference in learning curve was shown between the number 20 and number 33 medical center. Cases with the gender of male or female, age, body mass index, cases classified as stage 1, stage 2, stage 3 or stage 4 of the American Society of Anesthesiologists (ASA) Classification, cases with neoadjuvant therapy, duration of postoperative hospital stay of the number 20 medical center were 77, 20, (60±10)years, 24 kg/m 2(22 kg/m 2, 26 kg/m 2), 1, 88, 8, 0, 8, 8, 11 days (9 days, 13 days), respectively, versus 51, 31, (64±11)years, 23 kg/m 2(21 kg/m 2, 26 kg/m 2), 0, 35, 43, 1, 31, 16 days (13 day, 21 day) of number 33 medical center, showing significant differences in the above indicators between the two medical centers ( χ2 =6.442, t=-2.265, Z=-2.032, -6.870, χ2 =22.120, Z=-8.408, P<0.05). (5) Clinical data collection of the two surgery teams: the clinical data of 259 patients undergoing laparoscopic rectal cancer taTME from 5 medical centers were collected, including 46 cases in the number 2 medical center, 47 cases in the number 8 medical center, 78 cases in the number 18 medical center, 43 cases in the number 33 medical center and 45 cases in the number 44 medical center, respectively. (6) Surgical situations of laparoscopic rectal cancer taTME from the two surgery teams: four medical centers including the number 2, number 8, number 33 and number 44 medical center with close operation volume provided the clinical data of cases distributed in four operation stages. Among the four operation stages, the proportion of high-quality operation of TME was ≥50.0%(13/26), the incidence of postoperative complications was ≤35.0%(14/40) and the incidence of anastomotic leakage was ≤22.5%(9/40). There was no significant difference in the TME quality, postoperative complications or operation time among the four operation stages ( χ2 =3.252, 4.733, 8.848, P>0.05). There was a significant difference in the incidence of anastomotic leakage among the four operation stages ( P<0.05). (7) Learning curve of the two surgery teams: the number of operations corresponding to the turning point of learning curve in number 2 and number 8 medical center was 28 and 16, respectively. The number of operations corresponding to the turning points of learning curve in number 18, number 33 and number 44 medical center was 12 and 58, 10 and 36, 14 and 36, respectively. The overall curve of number 2 medical center was in line with the trend of learning curve and 28 cases of operations was the minimum number needed to cross the learning curve. The biggest difference in learning curve was shown between the number 2 and number 33 medical center. The age and cases with tumor in stage T0 and (or) Tis, stage T1, stage T2, stage T3 or stage T4 of the T staging of the number 2 and number 33 medical center were (60±12)years, 3, 1, 9, 11, 20 and (65±10)years, 2, 3, 22, 15, 0, respectively, showing significant differences in the above indicators between the two medical centers ( t=-2.280, Z=-4.033, P<0.05). Conclusion:Thirty-nine cases of operations was the minimum number for the one surgery team to cross the learning curve of laparoscopic rectal cancer taTME and 28 cases of operations was the minimum number for the two surgery teams to cross the learning curve of laparoscopic rectal cancer taTME.

Objective:To investigate the effects of cone beam computed tomography measurement of maxillary anterior teeth on implant success and patient satisfaction of maxillary anterior teeth.Methods:120 patients who underwent maxillary anterior teeth implantation in Hangzhou Dental Hospital from October 2017 to October 2019 were included in this study. They were randomly assigned to receive either conventional maxillary anterior teeth implantation (control group, n = 60) or cone beam computed tomography measurement of maxillary anterior teeth and maxillary anterior teeth implantation (study group, n = 60). The implant success rate was compared between the two groups. Alveolar bone thickness and ISQ value immediately, 3 and 12 months after implantation as well as patient satisfaction were compared between the two groups. Results:Implant success rate in the observation group was significantly higher than that in the control group [96.67% (58/60) vs. 85.00% (51/60), χ2 = 4.904, P < 0.05]. In the observation group, alveolar bone thickness at 3 and 12 months after implantation was (1.53 ± 0.05) mm and (1.78 ± 0.12) mm, respectively, which was significantly higher than that in the control group [(1.46 ± 0.04) mm, (1.64 ± 0.10) mm, t = 9.839, 8.066, both P < 0.001]. In the observation group, ISQ value at 3 and 12 months after implantation was (76.83 ± 5.49) and (82.91 ± 4.85), respectively, which was significantly higher than that in the control group [(67.81 ± 4.61), (74.18 ± 5.21), t = 11.324, 11.038, both P < 0.001). Total satisfaction rate in the observation group was significantly higher than that in the control group [95.00% (57/60) vs. 81.67% (49/60), χ2 = 5.175, P < 0.05]. Conclusion:Cone beam computed tomography measurement of maxillary anterior teeth can help increase implant success rate and patient satisfaction.

Objective:To compare the effects of pituitary down-regulation in combination with hormone replacement therapy endometrial preparation protocol and conventional hormone replacement therapy endometrial preparation protocol on outcomes of frozen-thawed embryo transfer (FET) in patients without endometriosis.Methods:The retrospective study included 3562 FET cycles was carried out between January 2012 and December 2017 in Reproductive Medicine Center, 73rd Group Army Hospital of PLA. Among them, 807 cycles were under hormone replacement therapy in combination with pituitary down-regulation with gonadotropin-releasing hormone agonist (GnRH-a) (experimental group) and 2755 cycles were under conventional hormone replacement therapy (control group). Association between endometrial preparation protocols and pregnancy and live birth was analyzed with multivariate logistic regression.Results:In experimental group, the maternal age [(31.19±4.58) years old] and endometrial thickness [(8.95±1.75) mm] were higher than those in control group [(29.84±4.23) years old, (8.46±1.41) mm, all P<0.001], the proportion of cycles with at least one good-quality embryo transferred (9.2%) was lower than that in control group (19.5%, P<0.001). The pregnancy rate (55.3%) was higher than that in control group (51.3%, P=0.045). The live birth rate showed an increasing trend in experimental group in comparison with that in control group, but the difference was not statistically significant ( P=0.78). In multivariate logistic regression with adjustment of confounding factors including maternal age, duration of infertility, endometrial thickness on the day of endometrial transition, number of embryos transferred, blastocyst transfer and at least one good-quality embryo transferred, the odds ratio ( OR) for pregnancy comparing experimental group with control group was 1.209 (95% CI=1.023-1.429) and OR for live birth was 1.246 (95% CI=1.053-1.474). Conclusion:Pituitary down-regulation in combination with hormone replacement therapy as endometrial preparation protocol for FET may achieve higher pregnancy rate and live birth rate than conventional hormone replacement protocol.

Objective:To compare the effects of pituitary down-regulation in combination with hormone replacement therapy endometrial preparation protocol and conventional hormone replacement therapy endometrial preparation protocol on outcomes of frozen-thawed embryo transfer (FET) in patients without endometriosis.Methods:The retrospective study included 3562 FET cycles was carried out between January 2012 and December 2017 in Reproductive Medicine Center, 73rd Group Army Hospital of PLA. Among them, 807 cycles were under hormone replacement therapy in combination with pituitary down-regulation with gonadotropin-releasing hormone agonist (GnRH-a) (experimental group) and 2755 cycles were under conventional hormone replacement therapy (control group). Association between endometrial preparation protocols and pregnancy and live birth was analyzed with multivariate logistic regression.Results:In experimental group, the maternal age [(31.19±4.58) years old] and endometrial thickness [(8.95±1.75) mm] were higher than those in control group [(29.84±4.23) years old, (8.46±1.41) mm, all P<0.001], the proportion of cycles with at least one good-quality embryo transferred (9.2%) was lower than that in control group (19.5%, P<0.001). The pregnancy rate (55.3%) was higher than that in control group (51.3%, P=0.045). The live birth rate showed an increasing trend in experimental group in comparison with that in control group, but the difference was not statistically significant ( P=0.78). In multivariate logistic regression with adjustment of confounding factors including maternal age, duration of infertility, endometrial thickness on the day of endometrial transition, number of embryos transferred, blastocyst transfer and at least one good-quality embryo transferred, the odds ratio ( OR) for pregnancy comparing experimental group with control group was 1.209 (95% CI=1.023-1.429) and OR for live birth was 1.246 (95% CI=1.053-1.474). Conclusion:Pituitary down-regulation in combination with hormone replacement therapy as endometrial preparation protocol for FET may achieve higher pregnancy rate and live birth rate than conventional hormone replacement protocol.

Objective To observe the serum vascular endothelial growth factor (VEGF),apelin and heme oxygenase-1 (HO-1) levels in patients with type 2 diabetes mellitus (T2DM) and to explore their their relationship with diabetic retinopathy (DR).Methods A total of 208 patients with T2DM and 50 healthy subjects (control group) from the Central Hospital of Western Hainan during January 2014 and December 2017 were selected in this study.Vision,slit lamp microscope,indirect ophthalmoscope and FFA examinations were performed on all the subjects.According to the results of the examinations combined with the DR clinical staging criteria,the patients were divided into non-DR (NDR) group,non-proliferative DR (NPDR) group,and proliferative DR (PDR) group,with 72,76 and 60 patients in each,respectively.The clinical data of each group were recorded,and the levels of fasting blood glucose (FPG),HbA1c,total cholesterol (TC),three acylglycerol (TG),high density lipoprotein (HDL-C),low density lipoprotein (LDL-C),VEGF,apelin and HO-1 were detected in each group.The receiver operating characteristic curve (ROC) were used to analyze the value of VEGF,apelin and HO-1 in predicting the occurrence of PDR.Correlation analysis of serum VEGF,Apelin and HO-1 with clinical parameters in PDR patients by Pearson correlation analysis.Results The level of VEGF (56.82± 10.16 vs 91.74±22.83,140.15±36.40,195.28±42.26 pg/ml)and apelin (2.95±0.53 vs 4.68±0.74,7.25±1.13,10.16± 1.35 ng/ml) in PDR group were significantly higher than those in NPDR,NDR and control groups (F=17.306,21.814;P＜0.05).The level of HO-1 (50.37±10.14 vs 43.58±8.16,30.25t6.28,22.60±4.72 mmol/L) in PDR group was significantly lower than those in NPDR,NDR and control groups (F=15.827,P＜0.05).The ROC curve analysis showed that the best cut-offvalues of serum VEGF,apelin and HO-1 were 162.50 pg/ml,8.30 ng/ml,27.13 mmol/L,and the three combined to predict PDR of AUC (95％CI)was 0.906 (0.849-0.962),and their sensitivity (90.3％) and specificity (83％) were better.The correlation analysis showed that the VEGF,apelin and HO-1 of PDR patients were correlated with the course of diabetes (r=0.382,0.416,-0.36;P＜0.05),FPG (r=0.438,0.460,-0.397;P＜0.05) and HbAlc (r=0.375,0.478,-0.405;P＜0.05),and the serum VEGF were correlated with apelin and HO-1 (r=0.793,-0.594;P＜0.01).Conclusion Elevated serum VEGF and apelin levels and reduced HO-1 levels are associated with the progression of DR,and the three combination helps predict the occurrence of PDR.