Objective:To preliminarily construct and apply a longitudinal trajectory model for the prognosis of intracerebral hemorrhage(ICH)based on blood urea nitrogen(BUN)characteristics.Methods:Clinical data from 320 ICH pati...Objective:To preliminarily construct and apply a longitudinal trajectory model for the prognosis of intracerebral hemorrhage(ICH)based on blood urea nitrogen(BUN)characteristics.Methods:Clinical data from 320 ICH patients admitted to our hospital between 2020 and 2024 were collected,including demographic information,National Institutes of Health Stroke Scale(NIHSS)scores at admission,dynamic changes in BUN levels during treatment,and 30-day survival outcomes.A latent class growth model(LCGM)was first used for preliminary modeling,followed by a latent growth mixture modeling(GMM)approach to determine the final model.Three classes of BUN trajectories for ICH prognosis were identified,and latent classes were established.GMM modeling was then performed on these latent classes,considering linear,quadratic,and cubic polynomial forms;six GMM models were constructed and individuals were assigned to latent trajectory groups for validation.Results:LCGM analysis ultimately identified three dynamic BUN trajectory groups:Sustained low-level group(76 cases,23.8%):BUN remained stable between 3.1-9.0 mmol/L,with the highest 30-day survival rate(98.7%).Fluctuating-declining group(222 cases,69.4%):BUN initially increased and then slowly decreased(peak at day 3:15.2 mmol/L),with a 30-day mortality of 8.1%(18/222),higher than the sustained low-level group.Sustained high-level group(22 cases,6.9%):BUN mean>9.0 mmol/L,with a 30-day mortality of 41.7%(P=0.000).GMM model fitting showed that the cubic polynomial GMM model was optimal(AIC=6754.474,BIC=6852.450,Entropy=0.905).Incorporating gender,age,and BMI as covariates revealed significant effects for gender(Estimate=0.045,-0.011,P=0.000,0.000).The AUC for predicting 30-day mortality was 0.88(sensitivity 82.8%,specificity 77.9%),which increased to 0.89 when combined with admission NIHSS scores.Conclusion:The LCGM+GMM model based on dynamic BUN trajectories effectively distinguishes prognostic subgroups in ICH patients.Patients with persistently elevated or fluctuating-rising BUN levels have a significantly higher mortality risk compared to those with sustained low levels.This model provides a new quantitative tool for early identification of high-risk patients and poor prognoses.展开更多
Objective To investigate a simple, valuable new method for coverage of the soft tissue defect over the lower one-third of the leg, ankle and the foot. Methods The distally based peroneus brevis muscle fkps were applie...Objective To investigate a simple, valuable new method for coverage of the soft tissue defect over the lower one-third of the leg, ankle and the foot. Methods The distally based peroneus brevis muscle fkps were applied for coverage of the soft tissue defects over the lower one-third of the leg,the ankle and the foot. The muscle flaps were covered with split-thickness skin grafts. Results The distally based peroneus brevis muscle flaps were applied for coverage of the soft tissue defects over the lower one-third of the leg, the ankle and the foot in 16 cases. The larges area of the soft tissue defect was 5 cm × 7 cm. The smallest was 3 cm × 4 cm. Primary healing occured in 14 cases undergoing muscle flap construction, second-stage healing occured in 2 cases, no total flap necrosis occured in any cases. Conclusion ThisChina Medical Abstracts(Surgery) technigue is a simple and complication are lesser. The successful rates are higher. This muscle flap is suitable to the mudium or small soft tissue展开更多
X90 pipeline steel is a new generation of pipeline steel developed after X80 and X100 pipeline steels,and it is now a new research hotspot at home.In order to thoroughly study the effect of applied potential on the so...X90 pipeline steel is a new generation of pipeline steel developed after X80 and X100 pipeline steels,and it is now a new research hotspot at home.In order to thoroughly study the effect of applied potential on the soil stress corrosion cracking(SCC)behavior of X90 pipeline steel,we investigated the SCC behaviors of base metal and weld joint samples in the straight-weld pipe of X90 pipeline steel at different applied potentials in near-neutral solution using electrochemical measurements methods and slow strain rate testing(SSRT).Besides,the fracture surfaces were observed through scanning electron microscope(SEM)and the mechanisms of the corrosion cracking behaviors were analyzed.And the following research results were obtained.First,the polarization curves of the base metal and weld joint samples in the NS4 solution present the typical characteristics of anodic dissolution but no activation–passivation phenomenon happens.Second,in the NS4 solution,the base metal and weld joint samples present SCC sensitivity.The SCC sensitivity indicator which is expressed by yield loss percentage elongation and yield loss percentage elongation area decreases firstly and then increases with the negative increase of the applied potential,and the SCC sensitivity of weld joint is higher than that of base metal.Third,there are three mechanisms on the SCC behaviors of base metal and weld joint samples,i.e.,anodic dissolution mechanism when the applied potential is open circuit potential(EOCP),anodic dissolution and hydrogen embrittlement mechanism when the applied potential is−850 mV,and hydrogen embrittlement mechanism when the applied potential is−1000 mV and−1200 mV.It is concluded that the research results can provide a technical support and theoretical basis for the large-scale application of X90 pipeline steel.展开更多
文摘Objective:To preliminarily construct and apply a longitudinal trajectory model for the prognosis of intracerebral hemorrhage(ICH)based on blood urea nitrogen(BUN)characteristics.Methods:Clinical data from 320 ICH patients admitted to our hospital between 2020 and 2024 were collected,including demographic information,National Institutes of Health Stroke Scale(NIHSS)scores at admission,dynamic changes in BUN levels during treatment,and 30-day survival outcomes.A latent class growth model(LCGM)was first used for preliminary modeling,followed by a latent growth mixture modeling(GMM)approach to determine the final model.Three classes of BUN trajectories for ICH prognosis were identified,and latent classes were established.GMM modeling was then performed on these latent classes,considering linear,quadratic,and cubic polynomial forms;six GMM models were constructed and individuals were assigned to latent trajectory groups for validation.Results:LCGM analysis ultimately identified three dynamic BUN trajectory groups:Sustained low-level group(76 cases,23.8%):BUN remained stable between 3.1-9.0 mmol/L,with the highest 30-day survival rate(98.7%).Fluctuating-declining group(222 cases,69.4%):BUN initially increased and then slowly decreased(peak at day 3:15.2 mmol/L),with a 30-day mortality of 8.1%(18/222),higher than the sustained low-level group.Sustained high-level group(22 cases,6.9%):BUN mean>9.0 mmol/L,with a 30-day mortality of 41.7%(P=0.000).GMM model fitting showed that the cubic polynomial GMM model was optimal(AIC=6754.474,BIC=6852.450,Entropy=0.905).Incorporating gender,age,and BMI as covariates revealed significant effects for gender(Estimate=0.045,-0.011,P=0.000,0.000).The AUC for predicting 30-day mortality was 0.88(sensitivity 82.8%,specificity 77.9%),which increased to 0.89 when combined with admission NIHSS scores.Conclusion:The LCGM+GMM model based on dynamic BUN trajectories effectively distinguishes prognostic subgroups in ICH patients.Patients with persistently elevated or fluctuating-rising BUN levels have a significantly higher mortality risk compared to those with sustained low levels.This model provides a new quantitative tool for early identification of high-risk patients and poor prognoses.
文摘Objective To investigate a simple, valuable new method for coverage of the soft tissue defect over the lower one-third of the leg, ankle and the foot. Methods The distally based peroneus brevis muscle fkps were applied for coverage of the soft tissue defects over the lower one-third of the leg,the ankle and the foot. The muscle flaps were covered with split-thickness skin grafts. Results The distally based peroneus brevis muscle flaps were applied for coverage of the soft tissue defects over the lower one-third of the leg, the ankle and the foot in 16 cases. The larges area of the soft tissue defect was 5 cm × 7 cm. The smallest was 3 cm × 4 cm. Primary healing occured in 14 cases undergoing muscle flap construction, second-stage healing occured in 2 cases, no total flap necrosis occured in any cases. Conclusion ThisChina Medical Abstracts(Surgery) technigue is a simple and complication are lesser. The successful rates are higher. This muscle flap is suitable to the mudium or small soft tissue
基金supported by the National Key R&D Program of China with Project No.2016YFC0801200.
文摘X90 pipeline steel is a new generation of pipeline steel developed after X80 and X100 pipeline steels,and it is now a new research hotspot at home.In order to thoroughly study the effect of applied potential on the soil stress corrosion cracking(SCC)behavior of X90 pipeline steel,we investigated the SCC behaviors of base metal and weld joint samples in the straight-weld pipe of X90 pipeline steel at different applied potentials in near-neutral solution using electrochemical measurements methods and slow strain rate testing(SSRT).Besides,the fracture surfaces were observed through scanning electron microscope(SEM)and the mechanisms of the corrosion cracking behaviors were analyzed.And the following research results were obtained.First,the polarization curves of the base metal and weld joint samples in the NS4 solution present the typical characteristics of anodic dissolution but no activation–passivation phenomenon happens.Second,in the NS4 solution,the base metal and weld joint samples present SCC sensitivity.The SCC sensitivity indicator which is expressed by yield loss percentage elongation and yield loss percentage elongation area decreases firstly and then increases with the negative increase of the applied potential,and the SCC sensitivity of weld joint is higher than that of base metal.Third,there are three mechanisms on the SCC behaviors of base metal and weld joint samples,i.e.,anodic dissolution mechanism when the applied potential is open circuit potential(EOCP),anodic dissolution and hydrogen embrittlement mechanism when the applied potential is−850 mV,and hydrogen embrittlement mechanism when the applied potential is−1000 mV and−1200 mV.It is concluded that the research results can provide a technical support and theoretical basis for the large-scale application of X90 pipeline steel.
