BACKGROUND:The influence of surgical delay on mortality and morbidity has been studied extensively among elderly hip fracture patients.However,most studies only focus on the timing of surgery when patients have alread...BACKGROUND:The influence of surgical delay on mortality and morbidity has been studied extensively among elderly hip fracture patients.However,most studies only focus on the timing of surgery when patients have already been hospitalized,without considering pre-admission waiting time.Therefore,the present study aims to explore the infl uence of admission delay on surgical outcomes.METHODS:In this retrospective study,we recorded admission timing and interval from admission to surgery for included patient.Other covariates were also collected to control confounding.The primary outcome was 1-year mortality.The secondary outcomes were 1-month mortality,3-month mortality,ICU admission and postoperative pneumonia.We mainly used multivariate logistic regression to determine the effect of admission timing on postoperative outcomes.An additional survival analysis was also performed to assess the impact of admission delay on survival status in the fi rst year after operation.RESULTS:The proportion of patients hospitalized on day 0,day 1,day 2 after injury was 25.4%,54.7%and 66.3%,respectively.And 12.6%patients visited hospital one week later after injury.Mean time from admission to surgery was 5.2 days(standard deviation 2.8 days).Hospitalization at one week after injury was a risk factor for 1-year mortality(OR 1.762,95%CI 1.026–3.379,P=0.041).CONCLUSION:Admission delay of more than one week is signifi cantly associated with higher 1-year mortality.As a supplement to the current guidelines which emphasizes early surgery after admission,we also advocate early admission once patients get injured.展开更多
为了提高波速的测量精度以便能观测到岩石临破裂前波速的微小变化,采用了波形的数值化,波的叠加,波的互相关和DTE(Subsample delay time estimate)方法和cosine插值,使时间分辨率提高到0.001μs,波速分辨率达到1m/s.在较小的应力增量(0....为了提高波速的测量精度以便能观测到岩石临破裂前波速的微小变化,采用了波形的数值化,波的叠加,波的互相关和DTE(Subsample delay time estimate)方法和cosine插值,使时间分辨率提高到0.001μs,波速分辨率达到1m/s.在较小的应力增量(0.17MPa)下测量了波的延迟时间,进而得到速度随应力的变化规律.实验结果显示在0.98破裂强度时岩石波速最大,然后下降直到破裂,此期间的波速下降量约30m/s.同时对临破裂前波的主频能量进行了计算,其变化规律与波速相同,认为破裂前的有关变化与岩石膨胀有关.最后用涨落模型讨论了延迟时间的方差变化.展开更多
Through the theory and experiment studies on rock dynamic fracture the limit strain is used as the optimum criterion of rock cracking. The main reasons of dynamic delay fracture are the relativity of rock dynamic resp...Through the theory and experiment studies on rock dynamic fracture the limit strain is used as the optimum criterion of rock cracking. The main reasons of dynamic delay fracture are the relativity of rock dynamic response with the strain rate and its lower tensile strength. The relation of yielding strain with over-stress impulse and the mechanism of tensile cracking are analysed.展开更多
文摘BACKGROUND:The influence of surgical delay on mortality and morbidity has been studied extensively among elderly hip fracture patients.However,most studies only focus on the timing of surgery when patients have already been hospitalized,without considering pre-admission waiting time.Therefore,the present study aims to explore the infl uence of admission delay on surgical outcomes.METHODS:In this retrospective study,we recorded admission timing and interval from admission to surgery for included patient.Other covariates were also collected to control confounding.The primary outcome was 1-year mortality.The secondary outcomes were 1-month mortality,3-month mortality,ICU admission and postoperative pneumonia.We mainly used multivariate logistic regression to determine the effect of admission timing on postoperative outcomes.An additional survival analysis was also performed to assess the impact of admission delay on survival status in the fi rst year after operation.RESULTS:The proportion of patients hospitalized on day 0,day 1,day 2 after injury was 25.4%,54.7%and 66.3%,respectively.And 12.6%patients visited hospital one week later after injury.Mean time from admission to surgery was 5.2 days(standard deviation 2.8 days).Hospitalization at one week after injury was a risk factor for 1-year mortality(OR 1.762,95%CI 1.026–3.379,P=0.041).CONCLUSION:Admission delay of more than one week is signifi cantly associated with higher 1-year mortality.As a supplement to the current guidelines which emphasizes early surgery after admission,we also advocate early admission once patients get injured.
文摘为了提高波速的测量精度以便能观测到岩石临破裂前波速的微小变化,采用了波形的数值化,波的叠加,波的互相关和DTE(Subsample delay time estimate)方法和cosine插值,使时间分辨率提高到0.001μs,波速分辨率达到1m/s.在较小的应力增量(0.17MPa)下测量了波的延迟时间,进而得到速度随应力的变化规律.实验结果显示在0.98破裂强度时岩石波速最大,然后下降直到破裂,此期间的波速下降量约30m/s.同时对临破裂前波的主频能量进行了计算,其变化规律与波速相同,认为破裂前的有关变化与岩石膨胀有关.最后用涨落模型讨论了延迟时间的方差变化.
文摘Through the theory and experiment studies on rock dynamic fracture the limit strain is used as the optimum criterion of rock cracking. The main reasons of dynamic delay fracture are the relativity of rock dynamic response with the strain rate and its lower tensile strength. The relation of yielding strain with over-stress impulse and the mechanism of tensile cracking are analysed.