Journal of biomechanics最新文献

{"title":"The force-calcium relationship is not affected by the cross-sectional area of skinned muscle fibres from rat soleus","authors":"Ian C. Smith ,&nbsp;Venus Joumaa ,&nbsp;Walter Herzog","doi":"10.1016/j.jbiomech.2025.112571","DOIUrl":"10.1016/j.jbiomech.2025.112571","url":null,"abstract":"<div><div>Proportionality between force and muscle cross-sectional area (CSA) is a foundational principle in muscle mechanics. However, CSA-normalized force (known as specific force) is often lower in fibres with large CSAs compared to fibres with small CSAs from the same sample population. Many physiological mechanisms proposed to account for CSA-dependence of specific force converge on the requirement for fibre CSA to impact the relationship between force and the concentration of force-activating calcium. To determine if features of the force-calcium relationship exhibited CSA-dependence in mammalian skinned muscle fibres, force-calcium relationships were generated for 85 skinned slow soleus fibres of male Sprague-Dawley rats (<em>n</em> = 54 rats, 1–5 fibres per rat, age = 24 weeks, experimental temperature = 18 °C) and fit using the Hill equation. Fibres were separated into quartiles based on their CSA and then compared. Despite specific force being 46 % higher (<em>P</em> &lt; 0.01) in the smallest (160 ± 51 mN∙mm⁻²; CSA = 3649 ± 708 μm²) compared to the largest (110 ± 20 mN∙mm⁻²; CSA = 8671 ± 1319 μm²) quartile, neither the calcium-sensitivity of force production (pCa50; <em>P</em> = 0.47; <em>F</em>(dFn = 3,DFd = 81) = 0.86) nor the Hill coefficient (<em>n_H</em>; <em>P</em> = 0.38; <em>F</em>(dFn = 3,DFd = 81) = 1.03) differed significantly between quartiles (smallest quartile: pCa50 = 6.015 ± 0.097, <em>n_H</em> = 1.80 ± 0.69; largest quartile: pCa50 = 6.062 ± 0.097, <em>n_H</em> = 1.63 ± 0.32). Force plateaus were observed at higher calcium concentrations in all fibres indicating that calcium was adequate for full activation. These findings add to the body of evidence suggesting that CSA-dependence of specific force in mammalian skinned fibres is an artifact attributable to the considerable imprecision associated with the assessment of fibre CSA, and not a physiological phenomenon which would require consideration when modeling muscle force output.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"182 ","pages":"Article 112571"},"PeriodicalIF":2.4,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143372611","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Step velocity asymmetry rather than step length asymmetry is updated in split-belt treadmill adaptation","authors":"Yuki Ishida ,&nbsp;Hikaru Yokoyama ,&nbsp;Naotsugu Kaneko ,&nbsp;Tatsuya Kato ,&nbsp;Kei-ichi Ishikawa ,&nbsp;Kimikata Nakazawa ,&nbsp;Ken Takiyama","doi":"10.1016/j.jbiomech.2025.112564","DOIUrl":"10.1016/j.jbiomech.2025.112564","url":null,"abstract":"<div><div>When discrepancies between planned and actual movements arise due to environmental changes, humans adjust movement parameters to achieve task goals. While motor adaptation has been extensively studied, the mechanisms involved in redundant movement parameters remain unclear. Split-belt treadmill adaptation, where each belt moves at a different speed, is an example of this phenomenon. Such adaptation initially induces gait asymmetry, which diminishes over time. Previous studies have postulated step length asymmetry as the target function; however, recent evidence challenges this assumption, leaving the target function undefined. This study investigates the target function by analyzing step parameter asymmetry using the goal-equivalent manifold and generalization predictability. The goal-equivalent manifold assesses whether adaptation is close to optimal in minimizing step parameter asymmetry, while generalization predictability reflects adaptation effects across different contexts, indicating potential target functions. We propose that step velocity asymmetry, rather than step length asymmetry, serves as the target function in split-belt treadmill adaptation. This framework facilitates the prediction and interpretation of both the learning process and the transfer of learning effects from trained to untrained conditions. In addition, it explains the overadaptation of step length asymmetry and the achievement of energy-efficient gait after adaptation. Therefore, we propose that step velocity asymmetry is the primary target function in split-belt treadmill adaptation.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"182 ","pages":"Article 112564"},"PeriodicalIF":2.4,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143422101","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Estimating temporal bone-implant stresses in patients with bone-anchored lower limbs","authors":"Jake P. Tinsley ,&nbsp;R. Dana Carpenter ,&nbsp;Nicholas W. Vandenberg ,&nbsp;Jason W. Stoneback ,&nbsp;Brecca M.M. Gaffney","doi":"10.1016/j.jbiomech.2025.112569","DOIUrl":"10.1016/j.jbiomech.2025.112569","url":null,"abstract":"<div><div>Bone-anchored limbs (BALs) are a transformative alternative for patients with lower-limb amputation who suffer from debilitating socket problems by eliminating the need for skin-to-prosthetic contact. Despite its successes, some individuals continue to face challenges with BALs, experiencing a loss of implant integration resulting in prosthetic loosening. A thorough understanding of biomechanical behavior at the residual limb and bone-implant interface is necessary to fully understand mechanical failure mechanisms. In addition, a deeper understanding of BAL biomechanical behavior would allow clinicians and researchers to predict and test different implant geometries, inform patient eligibility, rehabilitation strategies, and implantation methods in a safe and low-cost way. Thus, this study designed an innovative simulation method to quantify the temporal mechanical behavior of the residual limb in transfemoral and transtibial BALs by using subject-specific kinematics, musculoskeletal loads, and bone geometry and health. Our novel method was applied to two patients (one transtibial, one transfemoral) with similar BMI and age during level ground walking. Our results demonstrated a pattern of higher residual limb stresses in the transtibial model (26.80 MPa vs. 23.69 MPa). This study not only furthers our understanding of BAL biomechanics but introduces a versatile subject-specific methodology with direct applications in clinical practice. As we navigate the complexities of BAL implantation, this modeling platform lays the groundwork for more informed decision-making.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"182 ","pages":"Article 112569"},"PeriodicalIF":2.4,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143427820","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The effects of markerless inconsistencies are at least as large as the effects of the marker-based soft tissue artefact","authors":"S. Bousigues ,&nbsp;A. Naaim ,&nbsp;T. Robert ,&nbsp;A. Muller ,&nbsp;R. Dumas","doi":"10.1016/j.jbiomech.2025.112566","DOIUrl":"10.1016/j.jbiomech.2025.112566","url":null,"abstract":"<div><div>The soft tissue artefact is a well-known issue for marker-based motion analysis and markerless motion analysis is by definition free from this artefact. The goal of this study is to compare the limb skeletal inconsistencies generated by the neural networks in markerless motion capture and generated by the soft tissue artefact in marker-based motion capture using retrospective data.</div><div>Sixteen volunteers were included and were asked to perform four motor tasks (walk, sit-to-stand, stand-to-sit, countermovement jump) acquired with ten optoelectronic cameras and ten video cameras. Keypoint identification was performed in videos using Openpose. Triangulation and data augmentation algorithms were used to get an extension of anatomical landmarks. Then, lower limb skeletal inconsistencies (length variations and apparent joint dislocations) for both marker-based and markerless data were analyzed.</div><div>The length variation of the lower limbs was generally larger with markerless data (triangulated keypoints and augmented anatomical landmarks) as found with marker-based data. Mean dislocations were found smaller for the markerless data than for the marker-based data for the hip only.</div><div>The effect of the markerless inconsistencies are at least as large as the effect of the soft tissue artefact except for the hip dislocation, probably due to the soft tissue artefact that is main at the pelvis level. These inconsistencies are related to different phenomena than skin sliding as there are no correlation with joint flexion–extension angles. Thus, compensation methods proposed for soft tissue artefact are not all applicable.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"182 ","pages":"Article 112566"},"PeriodicalIF":2.4,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143378375","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanical modeling of the dynamic response of the knee joint angle in the evaluation of muscle nerve response and energy consumption","authors":"Hongyan Liu ,&nbsp;Bailu Zhao ,&nbsp;Qi Wang ,&nbsp;Junghee Lee ,&nbsp;Lei Liu ,&nbsp;Peilong Xu ,&nbsp;Jongchul Park","doi":"10.1016/j.jbiomech.2025.112565","DOIUrl":"10.1016/j.jbiomech.2025.112565","url":null,"abstract":"<div><div>Knee joint has large loads and pressures during human movement, and understanding knee joint’s dynamic response during movement is crucial to the study of movement mechanisms and the design of effective rehabilitation programs. In order to improve the accuracy of the mechanical model in the assessment of musculo-neural response and energy consumption in the knee joint movement mechanism, the study tries to calculate the values of mass, stiffness and damping based on the ‘mass-stiffness-damping’ model combined with the Vicon system and Moxy sensors, and further analyse the musculo-neural response and energy consumption based on the measurement of the joint angle and the joint torque. The muscle nerve response and energy consumption were further analyzed. After experimental analysis, these results show that the average fitting accuracy of the knee motion at different heights reaches more than 96.5%; in comparison of the sensitivity of the knee muscle nerve response, the research model is better than the other models in terms of the stability of the response; and the change of the knee angle and angular velocity at different walking speeds leads to different degrees of energy dissipation. In summary, the mechanical model based on the “mass-stiffness-damping” model combined with the application of motion capture system and muscle oxygenation monitoring equipment provides an important method and tool for the study of knee joint angle’s dynamic response, the muscle nerve response and the evaluation of energy consumption.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"182 ","pages":"Article 112565"},"PeriodicalIF":2.4,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143396293","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Computed gastrocnemius muscle moment arm based on wrapping objects derived from 3D ultrasound: Exploring the impact of ankle position and predictability of anthropometrics","authors":"Eric Irani ,&nbsp;Shuo Chen ,&nbsp;Sepehr Ramezani ,&nbsp;Amit Patel ,&nbsp;Jason B. Malone ,&nbsp;Hyunjun Shin ,&nbsp;Hwan Choi","doi":"10.1016/j.jbiomech.2025.112556","DOIUrl":"10.1016/j.jbiomech.2025.112556","url":null,"abstract":"<div><div>The objective of this study was to evaluate the effectiveness of subject-specific wrapping objects (SS.WOs) derived from 3D ultrasound measurements in calculating the musculotendon moment arm, particularly the lateral gastrocnemius muscle moment arm at the knee (Gas.lat KMA). Computed musculoskeletal modeling, essential for understanding human locomotion, often shows discrepancies compared to in vivo measurements. This research investigated whether SS.WOs, tailored to individual muscle paths across different joint configurations, could mitigate these discrepancies. Ten healthy participants were subjected to 3D ultrasound to record the Gas.lat path at various knee and ankle angles. This data was utilized to develop SS.WOs in a scaled Rajagopal Full-body model (SS-Rajagopal). We assessed the impact of the modeling approach and ankle position on the computed Gas.lat KMA by comparing it with results from two scaled generic models (SC-Rajagopal and SC-Gait2392). There was no significant effect of ankle position on Gas.lat KMA across all knee angles; however, the choice of modeling approach markedly influenced the outcomes. The computed Gas.lat KMA from SS-Rajagopal more closely matched in vivo measurements at higher knee angles compared to SC-Rajagopal. Significant correlations were observed between the computed Gas.lat KMA from both SS-Rajagopal and SC-Rajagopal with anthropometric measurements. However, no correlation was found between the properties of SS.WOs and individual anthropometrics. In conclusion, while optimization techniques such as muscle path computation with WOs improve musculoskeletal modeling efficiency, they may not fully address inter-subject variability.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"182 ","pages":"Article 112556"},"PeriodicalIF":2.4,"publicationDate":"2025-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143210025","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the number of steps required to measure the mean and variability of spatio-temporal parameters at preferred running speed","authors":"Antoine Godin ,&nbsp;Esther Eustache ,&nbsp;Yoshimasa Sagawa Jr. ,&nbsp;Laurent Mourot","doi":"10.1016/j.jbiomech.2025.112563","DOIUrl":"10.1016/j.jbiomech.2025.112563","url":null,"abstract":"<div><div>Preferred running speed is a relevant condition for measuring spatio-temporal parameters and their variability as it theoretically corresponds to an intensity where the energy cost, the biomechanical constraints and the pleasure are optimal. The objective of this study was to evaluate 1) the between-days reliability of spatio-temporal parameters measurements at preferred running speed and 2) the minimal number of steps required to obtain a representative measurement. Thirty-one recreational runners (age: 26 ± 5.5 years; running experience &gt; 2 years) performed three sessions of treadmill running at preferred running speed separated by 24 h. Spatio-temporal parameters were stride, step, contact and flight times, cadence, step length, duty factor, vertical and leg stiffness. Mean, linear and non-linear measurements of spatio-temporal parameters were computed. Reliability was determined using intraclass coefficient correlation and his 95 % confidence interval lower band (95 %LB). Number of steps required for intra-session representativity were defined as the first number of steps from which all measurements are equal to the measurement at the longer time series length. For all spatio-temporal parameters, mean data showed <em>excellent</em> reliability (95 %LB &gt; 0.90) but most spatio-temporal parameters linear and non-linear variability measurements showed <em>questionable</em> reliability (95 %LB &lt; 0.79). The absolute speed variation at preferred running speed (minimal detectable change 0.8 km/h) may explain these results. Representative values required between 16 and 352 steps for mean value of spatio-temporal parameters, between 16 and 400 steps for linear measurements, and between 336 and 704 steps for non-linear measurements.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"182 ","pages":"Article 112563"},"PeriodicalIF":2.4,"publicationDate":"2025-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143377893","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Motor control complexity estimation using gait measures in individuals post-stroke","authors":"Azarang Asadi ,&nbsp;Jill S. Higginson ,&nbsp;Jeffrey A. Reinbolt","doi":"10.1016/j.jbiomech.2025.112562","DOIUrl":"10.1016/j.jbiomech.2025.112562","url":null,"abstract":"<div><div>Motor control impairments post-stroke significantly limit walking ability, with residual gait impairments often persisting despite rehabilitation efforts. Integrating motor control-based assessments in post-stroke gait evaluations is essential for monitoring the underlying causes of the limited functionality and enhancing recovery outcomes. This study aimed to develop motor control-based post-stroke gait evaluation techniques using common gait measures to inform and guide rehabilitation decisions.</div><div>Subject-specific, forward-dynamic simulations of eight individuals with post-stroke gait undergoing a 12-weeks FastFES gait retraining program were created pre- and post-treatment to determine muscle activation patterns for muscle module analysis. The motor control complexity index was defined by the variance not accounted for by one module (VNAF₁) as a summary measure of the analysis. Twenty-eight gait measures were investigated, and the relevant measures were selected using feature selection methods and fed into a multiple linear regression model to estimate the motor control complexity index.</div><div>The motor control complexity of 182 gait cycles were quantified (0.164 ± 0.047). No strong relationship (quantified using Pearson correlation coefficients) was found between gait measures and the motor control complexity index. However, a combination of four gait measures from the paretic side (maximum hip abduction and knee flexion angle during swing, knee range of motion, and maximum paretic ankle power) explained most of the variation (R² = 0.66) in motor control complexity.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"182 ","pages":"Article 112562"},"PeriodicalIF":2.4,"publicationDate":"2025-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143465451","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A generalized objective CT-based method for quantifying articular fracture severity","authors":"Kevin N. Dibbern ,&nbsp;Andrew M. Kern ,&nbsp;Donald D. Anderson","doi":"10.1016/j.jbiomech.2024.112432","DOIUrl":"10.1016/j.jbiomech.2024.112432","url":null,"abstract":"<div><div>A CT-based method for objectively assessing fracture severity was previously developed and validated to address poor reliability in existing subjective fracture classification systems. The method involved quantifying the energy involved in creating a fracture. However, clinical utility of the method was hindered by reliance upon an intact contralateral CT and lengthy analysis time (8–10 h). Significant methodological improvements detailed here enable the assessment of fracture severity in any joints and bones, while obviating the need for an intact contralateral CT scan. Analysis time was reduced to &lt;2 h per case. Fracture energies computed using the new methods showed strong agreement (R² = 0.95, p &lt; 0.001) with prior results in analyzing twenty tibial pilon fractures. New metrics, articular fracture edge length and subchondral energy, were developed to better describe joint injuries by incorporating knowledge of preferential chondrocyte death along fracture edges. Based on two-year radiographic grading for these pilon fractures, fracture energy, articular fracture edge length, and subchondral energy were all significantly different (p &lt; 0.01) between cases that did or did not develop post-traumatic osteoarthritis. These developments enable measurement of fracture severity in larger populations and in more clinically relevant timeframes with articular fractures involving a variety of joints and bones. This generalized assessment method offers opportunity to change the way severity is considered in fracture treatment algorithms. Studies involving larger cohorts are anticipated to yield insights into the impact of fracture severity on PTOA risk and serve as a foundation for evaluating new treatment strategies.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"180 ","pages":"Article 112432"},"PeriodicalIF":2.4,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142949336","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Unlocking the multidimensionality of plantar pressure measurements for the evaluation of footwear in people with diabetes","authors":"L.E. Vossen,&nbsp;S.A. Bus,&nbsp;J.J. Van Netten","doi":"10.1016/j.jbiomech.2025.112502","DOIUrl":"10.1016/j.jbiomech.2025.112502","url":null,"abstract":"<div><div>The offloading effectiveness of custom-made footwear for people with diabetes is assessed using plantar pressure measurements. While such pressure data is multidimensional, it is mostly analyzed using a scalar − maximum peak plantar pressure (PMax). We aimed to investigate the associations between multiple peak plantar pressure parameters for footwear assessment and determine whether this assessment depends on the chosen parameter. In-shoe plantar pressure was measured in 77 participants with diabetes, peripheral neuropathy, and a recent ulcer or amputation history, while walking in their own custom-made footwear. Six peak plantar pressure parameters were extracted, both scalar (i.e. Pmax, time integral and gradient) and multidimensional (i.e. time curve, map and time map). Footwear was ranked from highest to lowest outcome for each parameter and associations with Pmax were compared using Spearman’s rank correlation coefficient. A footwear comparison within subjects using Fleiss’ Kappa analysis determined the agreement between parameters using two pairs of footwear of each participant. The rank correlation coefficient was moderate to strong between PMax and the other scalar parameters (ρ = 0.46–0.70), and negligible to weak between PMax and the multidimensional parameters (ρ = 0.03–0.25). Percentage agreement between parameters for the within-subject footwear comparison was poor (47.5 %, κ = 0.0652). We conclude that the association and agreement between in-shoe peak pressure parameters is low and the assessment of offloading effectiveness depends on the chosen parameter. This is the first step in unlocking the potential of a multidimensional approach in plantar pressure analysis, possibly changing how we evaluate footwear offloading effectiveness.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"180 ","pages":"Article 112502"},"PeriodicalIF":2.4,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142965127","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}