Dynamic Response and Injury Prediction for Lumbar Vertebrae of Pilots with Spondylolysis under Persistent Overload / 医用生物力学

Objective Based on construction and verification of the lumbar finite element model, the simulation calculation and injury prediction on dynamic response of normal lumbar model and L5 unilateral and bilateral spondylolysis models of the pilot were carried out, so as to explore the influence of persistent flight overload on normal and spondylolysis lumbar vertebrae of the pilot. Methods The precise finite element model of lumbavertebrae was established using reverse engineering software and computer-aided engineering (CAE) technology based on CT images. The validity of the lumbar vertebrae model was verified by static and dynamic in vitro experiments. The biomechanical simulation analysis on normal and spondylolysis lumbar vertebrae of the pilotunder persistent overload was carried out, and the spinal injury was predicted and analyzed by dynamic response index (DRI) injury evaluation and prediction method. Results The maximum isthmus stress of L5 vertebra in unilateral and bilateral spondylolysis models were 105. 29 MPa and 126. 32 MPa, respectively, which were significantly higher than those in normal model. The L4-5 and L5-S1 intervertebral discs of the spondylolysis model were more prone to premature degenerative changes than those of normal model. Combined with DRI spinal injury prediction method, the probability of spinal injury in normal lumbar vertebrae, lumbar vertebrae with L5 unilateral and bilateral spondylolysis were 0. 001 4% , 2. 26% and 3. 21% , respectively, and the probability of spinal injury was significantly increased after the occurrence of spondylolysis. Conclusions The spondylolysis increases the load of lumbar isthmus under flight overload. The results provide more accurate data support for the formulation of training programs and the development of protective devices to ensure flight safety

Dynamic Response Simulation and Damage Prediction of Pilot Cervical Vertebra During Maneuver Flight / 医用生物力学

Objective To simulate dynamic response of cervical spine of the pilot during typical maneuver flight movements using finite element method, as well as make analysis and prediction on damage failure of the pilot neck during flight by impact injury and fatigue injury model of biological tissues.Methods A geometrically accurate finite element model of the neck was constructed, and validity of the model was verified by relevant examples. Then, the acceleration curves of centrifugal trainer under different modes were loaded for numerical simulation, and impact injury and fatigue injury of tissues were predicted by using the universal cervical injury criterion and the fatigue damage model of biological tissues.Results The maximum stress of the vertebrae and intervertebral disc caused by overload impact was 66.53 MPa and 58.63 MPa respectively during typical maneuver flight. According to the Nij injury criteria, the maximum Nij was 0.096, which was lower than the injury tolerance threshold of 1, and would not cause direct acute injury to cervical tissues. Based on fatigue damage model of biological tissues, it was found that cancellous bone suffered fatigue failure under the condition of uninterrupted repeated loading for more than 40 000 times. Considering the limited flight career of the pilot, the vertebral tissues would not be fractured due to the accumulation of fatigue damage.Conclusions To a certain extent, the results can contribute to formulating pilot training and flight plans, and also provide data support for the development of its protective equipment.

Practice of reflective teaching method based on Bloom's educational theory in the standardized residency training of gynecology / 中华医学教育探索杂志

Objective:To explore the practical role of reflective teaching based on Bloom's educational theory in the standardized residency training of gynecology.Methods:A total of 31 residents who participated in the standardized residency training in the Gynecology Department of Beijing Shijitan Hospital Affiliated to Capital Medical University from July 2019 to January 2020 were classified as the control group, and 33 residents who participated in the standardized training from March 2020 to September 2020 were assigned to the observation group. The control group was given routine teaching, and the observation group was given reflective teaching based on Bloom's educational theory. The theoretical test scores and skill operation test scores before and after the training were compared between the two groups, and the clinical ability and teaching satisfaction of the two groups of residents were compared. SPSS 25.0 was used for t-test and Chi-square test. Results:After the standardized training, the scores of theoretical examination [(88.78±5.69) vs. (84.56±5.23)] and skill operation test [(89.37±5.75) vs. (85.22±5.34)] in the observation group were higher than those in the control group, with statistically significant differences. After the standardized training, the team cooperation ability, diagnosis and treatment technology operation ability, problem analysis and solving ability, clinical thinking ability and doctor-patient communication ability of the observation group were higher than those of the control group, and the differences were statistically significant. After the standardized training, the satisfactions with teaching mode, stimulating learning interest, improving self-study ability, improving diagnosis and treatment thinking ability, and improving problem analysis and solving ability in the observation group were higher than those in the control group, and the differences were statistically significant.Conclusion:Reflective teaching based on Bloom's educational theory can improve the professional theoretical knowledge level, clinical operation level, clinical ability and satisfaction of the gynecological residents, and help them to adapt to the clinical work faster.

Adult onset Still's disease with the initial symptom of pharyngalgia: a case report / 临床耳鼻咽喉头颈外科杂志

Adult onset Still's disease is a rare inflammatory disease characterized by spiking fevers, arthritis/ arthralgias, typical salmon-colored bumpy rash, pharyngalgia, myalgia and possible involvement of visceral organs. The diagnosis is exclusively based on clinical symptoms, according to the criteria, after the exclusion of well-known infectious, neoplastic, or other autoimmune/autoinflammatory disorders. This report includes one case of adult onset Still's disease with the initial symptom of pharyngalgia.

Meta-analysis of association between periodontal disease and preeclampsia / 中华围产医学杂志

Objective To explore the relationship between periodontal disease and preeclampsia and the effects of periodontal treatment on preeclampsia.Methods China National Knowledge Infrastructure,Chinese Biomedical Literature Database,WANGFANG DATA,China Dissertation Full-Text Database,China Proceedings of Conference Full-Text Database,Cochrane Library,PubMed,EMbase,Elsevier,Springer,and Science Direct OnSite were extracted from inception till September 30,2014.The case-control,cohort and randomized controlled trials about the association of matemal periodontal disease and preeclampsia were searched according to the inclusion and exclusion criteria.RevMan5.1 and Stata12.0 were used to test the heterogeneity of the results among the different studies and amalgamate the effect size using fixed or random effect models.Results Twenty studies (15 case-control and 5 cohort) involving 8 775 women assessed the association between periodontal disease and preeclampsia.A positive association was found (OR=2.48,95％CI:1.76-3.48,P ＜ 0.01).Meta-analysis of the case-control studies showed more than twice in the odds of preeclampsia with the presence of periodontal disease (OR=2.75,95％CI:1.93-3.92,P ＜ 0.01).Meta-analysis of cohort studies did not reveal any significant differences (OR=1.84,95％CI:0.91-3.74,P ＞ 0.05).Four randomized controlled trials with 3 712 women evaluated the effect of periodontal treatment on preeclampsia,and meta-analysis showed no relative risk reduction in preeclampsia with periodontal treatment (RR=1.04,95％CI:0.84-1.30,P ＞ 0.05).Conclusions Periodontal disease appears to be a possible risk factor for preeclampsia,but treatment during pregnancy does not prevent preeclampsia.High-quality prospective studies are needed to confirm the relationship between periodontal disease and preeclampsia.

VocaI PoIyps and Precancerous Lesions Treated with CO2 Laser and ConventionaI LaryngeaI Microsurgery / 听力学及言语疾病杂志

Objective To compare the efficacy of CO2 laser and conventional laryngeal microsurgery in the treatment of benign lesions of vocal cord (polyp of vocal cord) and precancerous lesions (leukoplakia of vocal cord) of patients. Methods A total of 60 patients with vocal cord polyps were selected, and randomly divided into two groups, each with 30 patients. Thirty patients with vocal cord leukoplakia were selected and randomly divided into two groups, each with 15 patients. One group was performed by cold instruments for lesion resection (conventional group), the other by CO2 laser for removal of diseased tissue or mucosal ablative surgery (laser group). Two groups of patients were examined by laryngostroboscope, electronic laryngoscopy, GRABS, VHI subjective ratings and objective voice analysis before operation and one week, one month and three months after operation. ResuIts The outcomes of those with vocal cord polyps in early recovery (1 week) laser group were slightly worse than the conventional group. In later recovery (1~3 months), with electronic laryngoscopy inspection, laryngostroboscope mucosal wave observation, the analysis of subjective and objective data from the two groups showed no significantly differences. For patients with vocal cord leukoplakia in early recovery (1 week), laser group slightly worse than the conventional group, in later recovery (1~3 months), there were no obvious difference between the two groups in electronic laryngoscopy inspection, laryngostroboscope mucosal wave observation, the analysis of subjective and ob_jective data. Follow -up operations, the recurrence rates in laser group was significantly lower than conventional group. ConcIusion The treatment by CO2 laser can significantly improve their pronunciation quality for vocal cord polyps and vocal cord leukoplakia patients, it has a good therapeutic effect, especially the long-term effective of vo_cal cord leukoplakia is better than conventional operation.

Studying on patient's nasal cycle of OSAHS with acoustic rhinometry / 临床耳鼻咽喉头颈外科杂志

Objective:To study the effect of OSAHS on adult nasal-cycle.Method:The nasal cycle of 20 healthy adults,18 patients of snoring and 22 patients of OSAHS were examined with acoustic rhinometry,which was performed every 30 minutes in 7 hours.Result:The ratio of nasal cycle in healthy adults was(19/20,95.0%), in snoring patients was(15/18,83.0%),in patients of OSAHS was(15/22,68.2%). The mean alteration amplitude of nasal cycle in healthy adults was significantly larger than that in patients with OSAHS (P<0.05).The distribution of the healthy adults and patients with OSAHS between the typical cycle categories was significantly different(P<0.05).Conclusion:The characteristics of nasal-cycle in of OSAHS patients were different with healthy adults,which maybe owing to change of physical function of nasal cavity.

Studying on patient's nasal cycle of OSAHS with acoustic rhinometry / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#To study the effect of OSAHS on adult nasal-cycle.@*METHOD@#The nasal cycle of 20 healthy adults, 18 patients of snoring and 22 patients of OSAHS were examined with acoustic rhinometry, which was performed every 30 minutes in 7 hours.@*RESULT@#The ratio of nasal cycle in healthy adults was (19/20, 95.0%), in snoring patients was (15/18, 83.0%), in patients of OSAHS was (15/22, 68.2%). The mean alteration amplitude of nasal cycle in healthy adults was significantly larger than that in patients with OSAHS (P < 0.05). The distribution of the healthy adults and patients with OSAHS between the typical cycle categories was significantly different (P < 0.05).@*CONCLUSION@#The characteristics of nasal-cycle in of OSAHS patients were different with healthy adults, which maybe owing to change of physical function of basal cavity.

Observation of cranial nerves in the cerebellopontine angle region by retrosigmoid approach / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#To investigate the anatomical structures of cranial nerves in the cerebellopontine angle region to offer anatomical data for clinical operation.@*METHOD@#A total of 52 adult cadaveric heads fixed in 10% formalin were used for this study. After cutting cerebellum and meningeal between transverse and sigmoid sinus, simulate operating method of retrosigmoid approach to observe the cranial nerves.@*RESULT@#External diameter and length of left V, VII, VIII, IX cranial nerves are (2.54 +/- 0.84) mm and (6.79 +/- 2.51) mm, (1.18 +/- 0.31) mm and (9.89 +/- 2.66) mm, (2.17 +/- 0.52) mm and (9.92 +/- 2.61) mm, (0.77 +/- 0.24) mm and (10.34 +/- 3.12) mm respectively. External diameter and length of right V , VII, VIII, IX cranial nerves are (2.52 +/- 0.86) mm and (6.91 +/- 2.66) mm, (1.14 +/- 0.31) mm and (10 +/- 2.96) mm, (2.13 +/- 0.63) m and (10.09 +/- 2.93) mm, (0.790.29) mm and (10.17 +/- 3.06) mm. intermedius nerve locate between facial nerve and acoustic nerve, external diameter of intermedius nerve is (0.47 +/- 0.91) mm (left) and (0.37 +/- 0.07) mm (right). Length of vagal nerve is (10.44 +/- 2.57) mm (left), (9.91 +/- 2.91) mm (right), rootlets of f vagal nerve is 6.37 +/- 2.26 (left) and 6.33 +/- 2.38 (right). external diameter of accessory nerve is (0.76 +/- 0.16) mm (left) and (0.81 +/- 0.19) mm (right).@*CONCLUSION@#This study provide anatomical data for retrosigmoid approach in the cerebellopontine angle region.