BACKGROUND:Based on variational principle and weighting technology of three-dimensional finite element method, human teeth with a complex morphology can be modeled, which helps to understand the stress distribution of dental hard tissue and prosthesis during the dynamic repair process. OBJECTIVE:To comprehensively analyze the three-dimensional finite element studies concerning biomechanics of dental prostheses, focusing on the effects of metal crown, porcelain thickness, root canal preparation and fil ing on the tooth stress. METHODS:A computer-based search of PubMed (1993-04/2012-09), China Academic Journal Network Publishing Database (2001-2008), and VIP (2001-2008) was performed by the first author to retrieve articles concerning the effects of metal crown, porcelain thickness, root canal preparation and fil ing on the tooth stress. The keywords were“porcelain-fused-to-metal, finite element method, stress analysis, root canal”in English and Chinese. Articles with repetitive contents or meta-analysis were ruled out. Then 40 articles were suitable for further analysis.RESULTS AND CONCLUSION:Finite element method has important significance to establish high-fidelity and high-accuracy models in oral medicine, thereby providing effective biomechanical information for the root canal treatment and post-treatment repair. Scholars continue to explore the stress distribution of dental prostheses during chewing. This review summarizes the stress changes of post and core crowns, supporting reference for further research. Three-dimensional finite element method can be used to build nonlinear three-dimensional finite element models with anisotropic biomechanical characteristics, and can gradual yimprove the transition from static analysis to a dynamic analysis, truly achieving accurate simulation of oral biology and dental morphology as wel as chewing function of the teeth.

Objective To explore the related factors of troublemaking risk in schizophrenia patients. Methods Investigation and analysis on demology,insight,treatment attitude and social function defects were conducted among 110 patients with schizophrenia and their families by general information scale,insight and treatment attitude questionnaire (ITAQ) and social disability screening schedule (SDSS).Results The score of troublemaking was (0.49±1.03),the score of social function defect was (11.94±3.92),and the score of insight and treatment attitude was (12.84±5.93). The risk of troublemaking in patients with schizophrenia less than one year was significantly lower than the risk of troublemaking in patients with schizophrenia more than one year,and the higher of the score of social function defect,the higher of the risk of patients′ troublemaking. Conclusions As for the prevention of troublemaking in patients with schizophrenia,we should pay attention to two aspects:giving more attention to patients with schizophrenia more than one year,and improving patients′ social function,in order to reduce the risk of troublemaking.

Objective: To observe the analgesic and anti-inflammatory effect of mandelic acid. Methods: Fifty Kunming mice were randomly divided into 5 groups:the blank control group (0. 1 ml/10 g), mandelic acid high (300 mg·kg-1), medium (200 mg ·kg-1 ) and low (140 mg·kg-1 ) dose groups, and the positive control ( aspirin) group, ig, qd. The analgesic effect of mandelic acid was observed by writhing test and hot plate method in mice. The ear swelling model caused by dimethyl benzene in mice was a-dopted to observe the analgesic effect. Results:Mandelic acid in each dose group could make the number of writhing in mice signifi-cantly reduced and pain threshold extended, and when compared with the blank control group, the difference was statistically significant (P<0. 01). The writhing times of mice mandelic acid high dose group was fewer than that of the positive control group, and there was no statistically significant between the groups (P>0. 05). In low and medium dose group, the writhing times of mice were more than those of the positive control group, and there was a significant difference between the low dose group and the positive control group( P<0. 05). The pain threshold of the mice in each mandelic acid dose group was higher than that of the positive control group, the pain threshold increased significantly in the high dose group before and after the administration, and the difference was statistically signifi-cant when compared with the positive control group (P<0. 05). The effect of mandelic acid on the ear swelling of mice was not signifi-cant, and when compared with the blank control group, the difference was not significant (P>0. 05). Conclusion:Mandelic acid has significant analgesic effect, while anti-inflammatory effect is not obvious.

Objective To investigate pathogenic genes related to the phenotype of fetus with severely short limbs in the first and second trimester by whole exome sequencing (WES). Methods Thirteen fetuses with severely short limbs detected by ultrasonography in the first and second trimester admitted in Chinese PLA General Hospital from September 2016 to June 2018 were collected. All cases were performed induced abortion, 6 of which were carried out karyotype analysis of amniotic fluid at the same time. WES and copy number variations (CNV) were performed on specimens from fetal tissues after labor induction. The suspected pathogenic mutations were validated by Sanger sequencing reactions. Results No abnormal karyotypes or pathological CNV were found. In 10 fetuses, pathogenic or possibly pathogenic mutations were detected in the following genes: COL2A1, FGFR3, COL1A1, COL1A2, DYNC2LI1 and TRIP11, all of which were essential to skeletal development. The diagnostic yield of WES in the fetuses with severe short limbs was 10/13. Conclusions In the first and second trimester, most of the fetuses with extremely short limbs suffer from monogenic diseases. WES is likely to be a valuable diagnostic testing option for the fetuses with severe short limbs.

Objective:To investigate the differences in ametropia among school-age children and between Han and Uygur ethnic groups in the main urban area of Kashgar, and to understand the epidemiological characteristics of myopia among children in Kashgar.Methods:A cross-sectional study was conducted.Random stratified sampling method was used to select the first to third grade students from 6 primary schools in the main urban areas of Kashgar, Xinjiang, from April to June 2018.Visual acuity was examined by the international standard visual acuity chart and refraction was detected by the automatic computer refractometer without cycloplegia.The subjects were classified into low vision (uncorrected visual acuity<0.8 in either eye), hyperopia≥2.00 D, myopia≥-1.00 D, astigmatism≥1.00 D and anisometropia≥1.00 D according to examination results.The percentage of different refraction states and percentage of different ethnic groups among myopic students in the three grades were analyzed.The study protocol was approved by an Ethics Committee of The First People's Hospital in Kashgar ([2021] QSY No.81).Results:A total of 6 108 students were enrolled, among which, there were 3 119 males and 2 989 females, 3 395 Uygur and 2 713 Han people, 2 016 first grade, 2 155 second grade and 1 937 third grade students.The detection rate of low vision was 13.5% (825/6 108) in the whole, 21.5% (584/2 713) in the Han people and 7.1% (241/3 395) in the Uygur people, 8.8% (176/2 016) in the first grade, 11.8% (254/2 155) in the second grade and 20.4% (395/1 937) in the third grade.The detection rate of myopia was 9.9% (606/6 108) in the whole, 17.6% (477/2 713) in the Han people and 3.8% (129/3 395) in the Uygur people, 4.4% (89/2 016) in the first grade, 8.1% (174/2 155) in the second grade and 17.7% (343/1 937) in the third grade.There were significant differences in percentage of low vision, myopia, astigmatism and anisometropia among different grades and between the two nationalities (all at P<0.001), and no significant difference in the percentage of hyperopia was found (P>0.05).Conclusions:The percentage of visual abnormalities and myopia in the first to third grade children in Kashgar is lower than the national average, but the percentage is gradually increasing with age.The percentage of visual abnormalities and myopia among Han pupils is close to the national average, and far higher than that of Uygur pupils.

Objective:To evaluate the safety and clinical efficacy of primary suturing of dog bite injuries on the head and face.Methods:A total of 42 cases with the dog bite injuries of Grade Ⅲ rabies exposure on the head and face(20 females and 22 males, aged from 1 to 81) were enrolled from October 2015 to October 2018 at the Department of Plastic Surgery, The Second People’s Hospital of Gansu Province. The primary suturing was performed after meticulous wound debridement and sufficient irrigation, the patients who were under 11 years old only received rabies vaccine for the rabies post-exposure prophylaxis, whereas the others were reinforced with tetanus antitoxin (1 500 IU) and human rabies immunoglobulin (20 IU/kg) around the wound, followed by Dermatix anti-scarring treatment for at least one year. Post-operative observation included wound healing and potential complications. All patients were followed up for facial deformities and bilateral symmetry, and the scars were assessed using the Vancouver Scar Scale (VSS).Results:Among the 42 cases, 38 cases (90.4%) were Class-A healed, 2 cases (4.8%) were Class-B healed (one of the two cases had a mandibular wound deep in the muscular layer. A deep abscess appeared in the neck 10 days after surgery, and was cured after puncture and drainage), and 2 cases (4.8%) were Class-C healed. Thirty-two patients had fever to different extent 2 to 5 days after surgery, and their body temperatures were below 38.5 ℃. The body temperature returned to normal after 1 to 2 days. During 6-24 months of follow-up, no tetanus and rabies occurred in all cases. During 1 to 2 years of follow-up, 1 of 42 cases had asymmetrical cheek 1 year post-operation. 1 case had scars on the upper eyelid 1 year after operation, and both eyes were asymmetric when eyes were open. Other 40 cases were recovered with bilateral symmetry without dysfunction of opening and closing the mouth and eyes. Facial contour recovery was cosmetically satisfactory with VSS score 1-3.Conclusions:Primary suturing of dog bite injuries on the head and face, according to the rabies prevention and treatment guideline, is a safe and effective treatment. It prevents rabies, and facial deformities and severe scar deformity in patients.

Objective:To evaluate the safety and clinical efficacy of primary suturing of dog bite injuries on the head and face.Methods:A total of 42 cases with the dog bite injuries of Grade Ⅲ rabies exposure on the head and face(20 females and 22 males, aged from 1 to 81) were enrolled from October 2015 to October 2018 at the Department of Plastic Surgery, The Second People’s Hospital of Gansu Province. The primary suturing was performed after meticulous wound debridement and sufficient irrigation, the patients who were under 11 years old only received rabies vaccine for the rabies post-exposure prophylaxis, whereas the others were reinforced with tetanus antitoxin (1 500 IU) and human rabies immunoglobulin (20 IU/kg) around the wound, followed by Dermatix anti-scarring treatment for at least one year. Post-operative observation included wound healing and potential complications. All patients were followed up for facial deformities and bilateral symmetry, and the scars were assessed using the Vancouver Scar Scale (VSS).Results:Among the 42 cases, 38 cases (90.4%) were Class-A healed, 2 cases (4.8%) were Class-B healed (one of the two cases had a mandibular wound deep in the muscular layer. A deep abscess appeared in the neck 10 days after surgery, and was cured after puncture and drainage), and 2 cases (4.8%) were Class-C healed. Thirty-two patients had fever to different extent 2 to 5 days after surgery, and their body temperatures were below 38.5 ℃. The body temperature returned to normal after 1 to 2 days. During 6-24 months of follow-up, no tetanus and rabies occurred in all cases. During 1 to 2 years of follow-up, 1 of 42 cases had asymmetrical cheek 1 year post-operation. 1 case had scars on the upper eyelid 1 year after operation, and both eyes were asymmetric when eyes were open. Other 40 cases were recovered with bilateral symmetry without dysfunction of opening and closing the mouth and eyes. Facial contour recovery was cosmetically satisfactory with VSS score 1-3.Conclusions:Primary suturing of dog bite injuries on the head and face, according to the rabies prevention and treatment guideline, is a safe and effective treatment. It prevents rabies, and facial deformities and severe scar deformity in patients.

Objective To study the effects of therapeutic communication on depressed emotion, treatment compliance and coping style of patients with depression. Methods A total of 80 patients with depression were divided into intervention group (n=40) and control group (n=40) by random number table. The patients of control group was given conventional nursing, and the patients of intervention group was given therapeutic communication on the basis of conventional nursing. After 8 weeks, the depressed emotion, treatment compliance and coping style of patients were observed. Results The depressed emotion, compliance and coping style of the intervention group had more improved than those of the control group, and the difference was statistically significant (P<0. 01). Conclusions Therapeutic communication can effectively improve the depressed emotion, compliance and coping style of patients with depression.

Objective:To investigate the status quo of multi-level pre-job training for clinical nursing teachers and analyze their training needs, so as to provide reference for the design of pre-job training for clinical nursing teachers.Methods:A cross-sectional survey method was used to investigate 172 clinical nursing teachers in a tertiary general hospital in Harbin from April 2020 to June 2020 with multi-level pre-job training mode. The status quo of pre-job training and the training needs of teachers were analyzed. SPSS 17.0 was used to process the original data statistically.Results:Among the 172 respondents, 138 teachers (80.2%) were under 35 years old, and 133 teachers (77.3%) had a bachelor's degree or less; 89 teachers (51.7%) confirmed that hospitals or departments would carry out pre-job training in a planned and organized way, 10 teachers (5.8%) said that hospitals or departments had never organized training, 41 teachers (23.8%) had never participated in pre-job training, and 80 teachers (46.5%) had participated in pre-job training 1-3 times. There were 5 duplicates in the first 8 training contents of in-hospital training and in-department training, including knowledge of common diseases, nursing procedures, communication skills, hospital rules and regulations, and teaching methods. The total score of training demand was (154.51± 40.35) points, and the overall demand rate was 81.3%, which was at the high level. The dimensions with the highest scoring rate were legal system and humanistic literacy, with a scoring rate of 83.0%. The dimension with the lowest score was teaching management, with a score of 74.9%. The scoring rate of training needs with the highest points won nine items respectively on students' basic quality (self-supervision, willingness to learn, professional quality, etc.) (84.7%), training of legal knowledge (84.4%), incompatibility of drugs commonly used in department (84.3%), nurse etiquette (83.3%), nursing risk prevention (83.1%), evaluation methods of student education (83.1%), nurse-patient communication skills (83.0%), nurses and patients medication observation points of commonly used drugs in the department (83.0%), and effects of commonly used drugs in department (82.9%). Among the top three training forms, 84 students (48.8%) received online learning, 74 students (43.0%) received lectures from experienced teachers in hospitals, and 72 students (41.9%) received experience exchange and sharing seminars.Conclusion:The talent structure of clinical nursing teachers in this hospital is relatively young, and the first education level is low. Therefore, the pre-job training of clinical nursing teachers should be strengthened vigorously. The awareness rate and participation rate of pre-job training are average, so we should strengthen the release of training information from various channels, improve the awareness rate of training activities, clarify the encouragement or reward measures to participate in pre-job training activities, and improve the participation rate of training activities. Pre-job training content is repeated at every level, with a gap between the training needs of teachers in clinical nursing teaching. It's suggested that the teaching hospitals combine with their training objects of training needs, take the online-offline mixed mode of training, reasonably plan training contents as a whole at all levels, avoid training content repetition and waste of teachers, and organize teachers to timely exchange and share experiences.

The adverse health effects of air pollution remains a daunting public health problem globally. The research of the health effects of air pollution provides important evidence for ambient air quality standard establishments and air pollution interventions. In recent years, causal inference has been gradually introduced into the observational study of environmental epidemiology, which provides more statistical method options for the study of causal relationships between air pollution and population health effects. Controlling confounders in observational studies is a major challenge for causal inference. This study introduces the causal inference methods for the identification and control of confounding factors currently used in the study of air pollution and population health effects, in order to provide methodological reference and basis for the causal inference study of air pollution and population health effects in China.