Objective: To analyze the change trends in the body shape indicators and proportions of students in Harbin from 2010 to 2024, and to investigate ergonomic compatibility of functional dimensions of school desks and chairs with current student shape indicators, so as to provide a reference for revising furniture standards of desks and chairs. Methods: Between September and November of both 2010 and 2024, a combination of convenience sampling and stratified cluster random sampling was conducted across three districts in Harbin, yielding samples of 6 590 and 6 252 students, respectively. Anthropometric shape indicators cluding height, sitting height, crus length, and thigh length-and their proportional changes were compared over the 15-year period. The 2024 data were compared with current standard functional dimensions of school furniture. The statistical analysis incorporated t-test and Mann-Whitney U- test. Results: From 2010 to 2024, average height increased by 1.8 cm for boys and 1.5 cm for girls; sitting height increased by 1.5 cm for both genders; crus length increased by 0.3 cm for boys and 0.4 cm for girls; and thigh length increased by 0.5 cm for both genders. The ratios of sitting height to height, and sitting height to leg length increased by less than 0.1 . The difference between desk chair height and 1/3 sitting height ranged from 0.4-0.8 cm. Among students matched with size 0 desks and chairs, 22.0% had a desk to chair height difference less than 0, indicating that the desk to chair height difference might be insufficient for taller students. The differences between seat height and fibular height ranged from -1.4 to 1.1 cm; and the differences between seat depth and buttock popliteal length ranged from -9.8 to 3.4 cm. Among obese students, the differences between seat width and 1/2 hip circumference ranged from -20.5 to -8.7 cm, while it ranged from -12.2 to -3.8 cm among non obese students. Conclusion Current furniture standards basically satisfy hygienic requirements; however, in the case of exceptionally tall and obese students, ergonomic accommodations such as adaptive seating allocation or personalized adjustments are recommended to meet hygienic requirements.

Objective To investigate the effects of ultrasound-guided thoracic paravertebral nerve block on postoperative analgesia and risk events in patients with scapular fracture caused by military training.Methods Seventy patients with scapular fracture who were admitted to the Marine Corps Hospital from January 2022 to December 2022 were randomly divided into control group and observation group.All fractures were caused by military training and treated with internal fixation under general anesthesia.The patients in the observation group additionally received ultrasound-guided thoracic paravertebral nerve block.The hemodynamics before and after skin incision,postoperative pain,and adverse events were compared between the two groups.Results The hemodynamic indexes did not significantly change at 5 min after skin incision(P>0.05).Heart rate(HR)and mean arterial pressure(MAP)in the observation group were lower than those in the control group at 5 min after skin incision(P<0.05).The visual analogue scale(VAS)scores at rest and in active state in the observation group were lower than those in the control group at 6 h and 12 h after surgery(P<0.05).The incidence of postoperative adverse events in the observation group was 5.71%,which was lower than that in the control group(25.71%,P<0.05).Conclusion Ultrasound-guided thoracic paravertebral nerve block can reduce the hemodynamic response caused by skin incision,postoperative pain,and the incidence of postoperative adverse events such as nausea and vomiting in patients with scapular fracture caused by military training.

Objective To assess the efficacy of a novel inguinal tourniquet in healthy individuals and to investigate the relationship between localized inguinal compression and femoral artery blood flow occlusion.Methods A self-controlled study was conducted.From November 9 to November 30,2024,11 volunteers were recruited at the Third Medical Center of Chinese PLA General Hospital.Three compression methods--finger pressure,a novel groin tourniquet,and a SAM junction tourniquet(SJT)—were applied bilaterally to the inguinal region until distal blood flow signals disappeared.Each compression method was tested in 22 trials with a 5-minute interval between operations.Differences in hemostatic efficacy between bilateral inguinal regions and across compression methods were compared.Subsequently,the novel tourniquet was incrementally pressurized in 120 mmHg multiples using an integrated pressure device to analyze trends in popliteal artery blood flow velocity.Observational indicators included the internal pressure of the tourniquet pressurization device,peak systolic velocity(PSV)of popliteal artery,inguinal surface pressure magnitude,inguinal surface pressure distribution,and pain scores(assessed using a single-dimensional numerical rating scale).Results No statistically significant difference was observed in the minimum pressure required to occlude femoral artery blood flow bilaterally(P>0.05).The success rates of femoral artery blood flow occlusion at the inguinal region were 100%for the novel inguinal tourniquet,SJT,and finger pressure.The novel inguinal tourniquet induced the highest pain scores,ranging from 5 to 8.A significant reduction in PSV of popliteal artery was noted when the intra-tourniquet pressure reached 360 mmHg and 480 mmHg(P<0.05),with a 95%hemostasis efficacy observed within the range of 360-600 mmHg.No significant association was observed between the recovery of popliteal artery blood flow after limb movement and inguinal pressure distribution(P>0.05).The PSV of popliteal artery exhibited the strongest negative correlation with the average pressure within the inguinal compression area(r=-0.79,P<0.001),with a linear regression fitting line of y=69.69-0.13x(P<0.001,R2=0.58).Conclusions The novel inguinal tourniquet effectively occludes femoral artery blood flow within a pressure range of 360-600 mmHg,accompanied by moderate-to-severe pain.Its hemostatic mechanism mainly relies on increasing the mean pressure within the inguinal compression area.

For middle-aged and elderly patients with conditions such as spinal fractures and degenerative spinal diseases, spinal internal fixation is a core surgical procedure for reconstructing spinal stability, heavily relying on the biomechanical stability provided by pedicle screw systems. Whereas, these patients are often complicated by osteoporosis that can significantly compromise the stability of the bone-pedicle screw interface, leading to a marked increase in pedicle screw loosening and surgical failure rates. The bone cement-augmented pedicle screw technique, which involves injecting bone cement into the vertebral body or screw trajectory to optimize the mechanical properties of the bone-pedicle screw composite, has been proven to significantly enhance fixation strength and effectively prevent screw-related failures, thereby reducing the incidence of internal fixation failure in high-risk populations undergoing spinal fusion. However, the widespread clinical application of this technique has faced challenges such as inaccurate clinical decision-making (indication and contraindication selection), non-standardized operative practices, and insufficient awareness of complication prevention, resulting in considerable variability in clinical outcomes and even severe complications. To address this, Prof. Luo Fei from First Affiliated Hospital of Army Medical University initiated the project and the Chinese Association Orthopaedic Surgeons organized relevant experts to develop the Evidence-based clinical practice guideline for bone cement-augmented pedicle screw technique ( version 2025), based on current evidence. The guidelines put forward 8 recommendations regarding the clinical value, scope of application, and operational standards of the technique, aiming to provide evidence-based medical support and technical standardization for clinical decision-making.

Objective:To explore the genetic characteristics and pathogenesis for a child with mosaicism trisomy 21 and Congenital leukemia (CL).Methods:A child who was admitted to Ningbo Women and Children′s Hospital in March 2023 was selected as the study subject. A retrospective analysis was carried out on the clinical data, laboratory test results, immunophenotyping, and genetic characteristics of the child. This study was approved by the Medical Ethics Committee of the Hospital (Ethics No.: EC2024-063).Results:Whole genome sequencing (WGS) revealed that the child has mosaicism trisomy of chromosome 21, with a ratio of approximately 74%. In addition, pathogenic copy number variations involving multiple OMIM genes that could explain his clinical phenotype were detected and rated as pathogenic based on the guidelines from the American College of Medical Genetics and Genomics (ACMG). No pathogenic variant was detected with the GATA1 gene. Blood immune typing of the child conformed to the immunophenotype of acute myeloid leukemia. Conclusion:For children with trisomy 21, even in the absence of GATA1 gene variants, the occurrence of CL should be monitored, and early diagnosis and treatment are of great significance for improving the prognosis.

Traumatic main bronchus rupture is a relatively rare injury in thoracic trauma, which is extremely critical, with a mortality rate as high as 70% - 80%. The complete rupture and displacement of the traumatic cervical trachea can lead to asphyxia, hypoxia, and cardiac arrest, even death of the patient in a short time. We performed emergency surgery with the support of extracorporeal membrane oxygenation for a case of traumatic cervical tracheal trunk complete rupture and displacement combined with cardiac arrest and achieved a successful rescue. We summarized our experience and found that timely surgical reconstruction of the airway is the key to increasing the traumatic main bronchus rupture survival of patients.
Humans ; Extracorporeal Membrane Oxygenation ; Heart Arrest/etiology* ; Rupture ; Trachea/surgery*

PURPOSE: To investigate the incidence and influencing factors of bone loss in patients with spinal cord injury (SCI). METHODS: A retrospective case-control study was conducted. Patients with SCI in our hospital from January 2019 to March 2023 were collected. According to the correlation between bone mineral density (BMD) at different sites, the patients were divided into the lumbar spine group and the hip joint group. According to the BMD value, the patients were divided into the normal bone mass group (t > -1.0 standard deviation) and the osteopenia group (t ≤ -1.0 standard deviation). The influencing factors accumulated as follows: gender, age, height, weight, cause of injury, injury segment, injury degree, time after injury, start time of rehabilitation, motor score, sensory score, spasticity, serum value of alkaline phosphatase, calcium, and phosphorus. The trend chart was drawn and the influencing factors were analyzed. SPSS 26.0 was used for statistical analysis. Correlation analysis was used to test the correlation between the BMD values of the lumbar spine and bilateral hips. Binary logistic regression analysis was used to explore the influencing factors of osteoporosis after SCI. p < 0.05 was considered statistically significant. RESULTS: The incidence of bone loss in patients with SCI was 66.3%. There was a low concordance between bone loss in the lumbar spine and the hip, and the hip was particularly susceptible to bone loss after SCI, with an upward trend in incidence (36% - 82%). In this study, patients with SCI were divided into the lumbar spine group (n = 100) and the hip group (n = 185) according to the BMD values of different sites. Then, the lumbar spine group was divided into the normal bone mass group (n = 53) and the osteopenia group (n = 47); the hip joint group was divided into the normal bone mass group (n = 83) and the osteopenia group (n = 102). Of these, lumbar bone loss after SCI is correlated with gender and weight (p = 0.032 and < 0.001, respectively), and hip bone loss is correlated with gender, height, weight, and time since injury (p < 0.001, p = 0.015, 0.009, and 0.012, respectively). CONCLUSIONS The incidence of bone loss after SCI was high, especially in the hip. The incidence and influencing factors of bone loss in the lumbar spine and hip were different. Patients with SCI who are male, low height, lightweight, and long time after injury were more likely to have bone loss.
Humans ; Spinal Cord Injuries/complications* ; Male ; Female ; Retrospective Studies ; Incidence ; Adult ; Bone Density ; Middle Aged ; Case-Control Studies ; Osteoporosis/etiology* ; Lumbar Vertebrae ; Bone Diseases, Metabolic/etiology* ; Aged ; Risk Factors

In this study,an ON/OFF type micro-valve with a sandwich(glass-silicon-glass)structure was designed and fabricated based on the micro-electro-mechanical system(MEMS)technique.The deformable membrane of this micro-valve was prepared on the silicon on insulator(SOI)substrate and sealed using Si-Si bonding and anodic bonding methods.The micro-valve had high-temperature stability and was suitable for integration with other gas chromatography components.The deformable membrane with a thickness of 10 μm was processed on the top silicon of the SOI substrate.The flow control of the micro-valve could be achieved by changing the driving pressure applied to the deformable membrane to deform it.Compared with polymer membranes,the deformable membrane prepared on the top layer silicon of SOI had better temperature stability and could be released using the deep reactive ion etching technique after silicon-silicon bonding,avoiding deformation during the preparation process.In addition,due to the small gap between the membrane and the inlet/outlet holes,the dead volume of the microvalve was very small.The test results indicated that the micro-valve achieved flow control and ON/OFF functions with good repeatability.

A monolithic integrated gas chromatography chip,consisting of a micro gas chromatography column(μGCC)and a micro helium discharge ionization detector(μHDID)was proposed.The chip was fabricated using micro electromechanical system(MEMS)technique,and its sensitivity was improved from two aspects.On one hand,open tubular column was selected as the separation device,and the auxiliary helium channel width of μHDID was modulated based on the microchannel width of the μGCC to match the flow rates of μHDID and μGCC.On the other hand,the electrode structure inside the μHDID collection zone was optimized,a bias electrode group around the collection electrode was constructed,and the ion collection efficiency was improved.After coating HKUST-1 as the stationary phase,the monolithic integrated gas chromatography chip could achieve baseline separation and detection of light hydrocarbon gas mixture(methane,ethane,propane,andn-butane),with a detection limit for propane as low as 25 pg.The chip could carried out test under temperature-programmed conditions,with a resolution of 9.24 for ethane and propane.