Objective: To understand the status quo of PICC Catheter-associated Skin Impairment (CASI) in some hospitals at all levels in Jingzhou city, and to explore the risk factors for PICC Catheter-associated Skin Impairment...Objective: To understand the status quo of PICC Catheter-associated Skin Impairment (CASI) in some hospitals at all levels in Jingzhou city, and to explore the risk factors for PICC Catheter-associated Skin Impairment. Methods: From June 2019 to July 2020, a self-made questionnaire for CASI status was used to facilitate the extraction of CASI patients in PICC in some hospitals at all levels in Jingzhou city. Local skin lesions were collected and classified during PICC maintenance, and the damage types, occurrence frequency and related influencing factors of CASI were counted to identify independent risk factors. Results: In this study, there were 173 cases of CASI in PICC’s patients including local infection 56.1% (97/173), exudation at the puncture site 16.8% (29/173), irritant dermatitis 21.4% (37/173), allergic dermatitis 4.6% (8/173), and tension injury 1.2% (2/173). After univariate analysis, there were statistically significant differences between CASI occurrence type and duration of catheter wear, age, underlying disease, skin moisture and hyperhidrosis, PICC maintenance as required, hospital grade maintenance and intermittent chemotherapy (P < 0.05). Then, disordered multiple Logistic regression analysis was performed, and exudation at the puncture site was used as the reference group. The results showed that patients with PICC were more likely to have CASI if they were aged, long catheter time, had diabetes, had moist and sweaty skin, and were in the intermittent stage of chemotherapy. Conclusion: The incidence of CASI is high in patients aged 70 - 79 years, and local infection is the most common. PICC’s patients with diabetes are at high risk of CASI. PICC’s patients with excessive sweating are more likely to have CASI. The intermittent stage of chemotherapy is the excessive CASI;time with tube affects CASI occurrence.展开更多
The serpentine convergent-divergent nozzle represents an optimal configuration for nextgeneration fighter aircraft characterized by low detectability and high thrust-to-weight ratio.In contrast to the serpentine conve...The serpentine convergent-divergent nozzle represents an optimal configuration for nextgeneration fighter aircraft characterized by low detectability and high thrust-to-weight ratio.In contrast to the serpentine convergent nozzle,such configuration offers increased design flexibility with additional parameters,leading to heightened interactions among these parameters.As such,it is crucial to reveal the influence of design parameters on the aerodynamic performance of the serpentine convergent-divergent nozzle and the multifactor interaction,as well as its mechanism.Therefore,the influence,interaction and sensitivity of parameters on the aerodynamic performance of the nozzle were numerically investigated using the orthogonal test method.Additionally,the influence mechanism of the convergence angle,throat aspect ratio,and axial length to inlet diameter on the flow characteristics of the nozzle was investigated in detail.The results show that the convergence angle is identified as the main factor affecting the aerodynamic parameters of the nozzle.As the convergence angle increases,the thrust coefficient,total pressure recovery coefficient and discharge coefficient gradually decrease.The interaction between throat aspect ratio and other parameters is obvious.Different design parameters affect the local loss and the friction loss by affecting the curvature and wetted perimeter area,resulting in different aerodynamic characteristics of serpentine convergent-divergent nozzle.展开更多
BACKGROUND Gallbladder cancer(GBC)is the most common malignant tumor of the biliary system,and is often undetected until advanced stages,making curative surgery unfeasible for many patients.Curative surgery remains th...BACKGROUND Gallbladder cancer(GBC)is the most common malignant tumor of the biliary system,and is often undetected until advanced stages,making curative surgery unfeasible for many patients.Curative surgery remains the only option for long-term survival.Accurate postsurgical prognosis is crucial for effective treatment planning.tumor-node-metastasis staging,which focuses on tumor infiltration,lymph node metastasis,and distant metastasis,limits the accuracy of prognosis.Nomograms offer a more comprehensive and personalized approach by visually analyzing a broader range of prognostic factors,enhancing the precision of treatment planning for patients with GBC.AIM A retrospective study analyzed the clinical and pathological data of 93 patients who underwent radical surgery for GBC at Peking University People's Hospital from January 2015 to December 2020.Kaplan-Meier analysis was used to calculate the 1-,2-and 3-year survival rates.The log-rank test was used to evaluate factors impacting prognosis,with survival curves plotted for significant variables.Single-factor analysis revealed statistically significant differences,and multivariate Cox regression identified independent prognostic factors.A nomogram was developed and validated with receiver operating characteristic curves and calibration curves.Among 93 patients who underwent radical surgery for GBC,30 patients survived,accounting for 32.26%of the sample,with a median survival time of 38 months.The 1-year,2-year,and 3-year survival rates were 83.87%,68.82%,and 53.57%,respectively.Univariate analysis revealed that carbohydrate antigen 19-9 expre-ssion,T stage,lymph node metastasis,histological differentiation,surgical margins,and invasion of the liver,ex-trahepatic bile duct,nerves,and vessels(P≤0.001)significantly impacted patient prognosis after curative surgery.Multivariate Cox regression identified lymph node metastasis(P=0.03),histological differentiation(P<0.05),nerve invasion(P=0.036),and extrahepatic bile duct invasion(P=0.014)as independent risk factors.A nomogram model with a concordance index of 0.838 was developed.Internal validation confirmed the model's consistency in predicting the 1-year,2-year,and 3-year survival rates.CONCLUSION Lymph node metastasis,tumor differentiation,extrahepatic bile duct invasion,and perineural invasion are independent risk factors.A nomogram based on these factors can be used to personalize and improve treatment strategies.展开更多
文摘Objective: To understand the status quo of PICC Catheter-associated Skin Impairment (CASI) in some hospitals at all levels in Jingzhou city, and to explore the risk factors for PICC Catheter-associated Skin Impairment. Methods: From June 2019 to July 2020, a self-made questionnaire for CASI status was used to facilitate the extraction of CASI patients in PICC in some hospitals at all levels in Jingzhou city. Local skin lesions were collected and classified during PICC maintenance, and the damage types, occurrence frequency and related influencing factors of CASI were counted to identify independent risk factors. Results: In this study, there were 173 cases of CASI in PICC’s patients including local infection 56.1% (97/173), exudation at the puncture site 16.8% (29/173), irritant dermatitis 21.4% (37/173), allergic dermatitis 4.6% (8/173), and tension injury 1.2% (2/173). After univariate analysis, there were statistically significant differences between CASI occurrence type and duration of catheter wear, age, underlying disease, skin moisture and hyperhidrosis, PICC maintenance as required, hospital grade maintenance and intermittent chemotherapy (P < 0.05). Then, disordered multiple Logistic regression analysis was performed, and exudation at the puncture site was used as the reference group. The results showed that patients with PICC were more likely to have CASI if they were aged, long catheter time, had diabetes, had moist and sweaty skin, and were in the intermittent stage of chemotherapy. Conclusion: The incidence of CASI is high in patients aged 70 - 79 years, and local infection is the most common. PICC’s patients with diabetes are at high risk of CASI. PICC’s patients with excessive sweating are more likely to have CASI. The intermittent stage of chemotherapy is the excessive CASI;time with tube affects CASI occurrence.
基金supported by the National Science and Technology Major Project of China(No.J2019-Ⅲ-0009-0053)。
文摘The serpentine convergent-divergent nozzle represents an optimal configuration for nextgeneration fighter aircraft characterized by low detectability and high thrust-to-weight ratio.In contrast to the serpentine convergent nozzle,such configuration offers increased design flexibility with additional parameters,leading to heightened interactions among these parameters.As such,it is crucial to reveal the influence of design parameters on the aerodynamic performance of the serpentine convergent-divergent nozzle and the multifactor interaction,as well as its mechanism.Therefore,the influence,interaction and sensitivity of parameters on the aerodynamic performance of the nozzle were numerically investigated using the orthogonal test method.Additionally,the influence mechanism of the convergence angle,throat aspect ratio,and axial length to inlet diameter on the flow characteristics of the nozzle was investigated in detail.The results show that the convergence angle is identified as the main factor affecting the aerodynamic parameters of the nozzle.As the convergence angle increases,the thrust coefficient,total pressure recovery coefficient and discharge coefficient gradually decrease.The interaction between throat aspect ratio and other parameters is obvious.Different design parameters affect the local loss and the friction loss by affecting the curvature and wetted perimeter area,resulting in different aerodynamic characteristics of serpentine convergent-divergent nozzle.
基金Supported by Xiao-Ping Chen Foundation for The Development of Science and Technology of Hubei Province,No.CXPJJH122002-061.
文摘BACKGROUND Gallbladder cancer(GBC)is the most common malignant tumor of the biliary system,and is often undetected until advanced stages,making curative surgery unfeasible for many patients.Curative surgery remains the only option for long-term survival.Accurate postsurgical prognosis is crucial for effective treatment planning.tumor-node-metastasis staging,which focuses on tumor infiltration,lymph node metastasis,and distant metastasis,limits the accuracy of prognosis.Nomograms offer a more comprehensive and personalized approach by visually analyzing a broader range of prognostic factors,enhancing the precision of treatment planning for patients with GBC.AIM A retrospective study analyzed the clinical and pathological data of 93 patients who underwent radical surgery for GBC at Peking University People's Hospital from January 2015 to December 2020.Kaplan-Meier analysis was used to calculate the 1-,2-and 3-year survival rates.The log-rank test was used to evaluate factors impacting prognosis,with survival curves plotted for significant variables.Single-factor analysis revealed statistically significant differences,and multivariate Cox regression identified independent prognostic factors.A nomogram was developed and validated with receiver operating characteristic curves and calibration curves.Among 93 patients who underwent radical surgery for GBC,30 patients survived,accounting for 32.26%of the sample,with a median survival time of 38 months.The 1-year,2-year,and 3-year survival rates were 83.87%,68.82%,and 53.57%,respectively.Univariate analysis revealed that carbohydrate antigen 19-9 expre-ssion,T stage,lymph node metastasis,histological differentiation,surgical margins,and invasion of the liver,ex-trahepatic bile duct,nerves,and vessels(P≤0.001)significantly impacted patient prognosis after curative surgery.Multivariate Cox regression identified lymph node metastasis(P=0.03),histological differentiation(P<0.05),nerve invasion(P=0.036),and extrahepatic bile duct invasion(P=0.014)as independent risk factors.A nomogram model with a concordance index of 0.838 was developed.Internal validation confirmed the model's consistency in predicting the 1-year,2-year,and 3-year survival rates.CONCLUSION Lymph node metastasis,tumor differentiation,extrahepatic bile duct invasion,and perineural invasion are independent risk factors.A nomogram based on these factors can be used to personalize and improve treatment strategies.