Large scaled uniform and size-controllable magnetic submicroparticles(MSPs) were synthesized via solvothermal method with ferric chloride as iron source and sodium acetate as trapping agent. The influence of Fe^(3+) a...Large scaled uniform and size-controllable magnetic submicroparticles(MSPs) were synthesized via solvothermal method with ferric chloride as iron source and sodium acetate as trapping agent. The influence of Fe^(3+) and Na Ac contents on the size distribution of MSPs was investigated. The structural and morphological properties of the synthesized particles were studied by scanning electron microscopy(SEM), X-ray power diffraction(XRD) and vibrating sample magnetometer(VSM). The well-dispersed MSPs with size of 100-1000 nm were obtained by simply adjusting the contents of Fe^(3+) and NaA c. In addition, the hemolysis and cytotoxicity of Fe_3O_4 MSPs, and their ability to case arrest in cell life-cycles were studied. The results indicate that larger size could lead to lower hemolysis. From MTT(3-(4,5-dimethylthuazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, the interactions between MSPs and adhesive mouse fibroblast cell line(L929) were probed. Larger size of Fe_3O_4 MSPs demonstrates lower cell viability following an exposure to the cells.展开更多
Background:Cardiopulmonary resuscitation(CPR)strategies in COVID-19 patients differ from those in patients suffering from cardiogenic cardiac arrest.During CPR,both healthcare and non-healthcare workers who provide re...Background:Cardiopulmonary resuscitation(CPR)strategies in COVID-19 patients differ from those in patients suffering from cardiogenic cardiac arrest.During CPR,both healthcare and non-healthcare workers who provide resuscitation are at risk of infection.The Working Group for Expert Consensus on Prevention and Cardiopulmonary Resuscitation for Cardiac Arrest in COVID-19 has developed this Chinese Expert Consensus to guide clinical practice of CPR in COVID-19 patients.Main recommendations:1)A medical team should be assigned to evaluate severe and critical COVID-19 for early monitoring of cardiac-arrest warning signs.2)Psychological counseling and treatment are highly recommended,since sympathetic and vagal abnormalities induced by psychological stress from the COVID-19 pandemic can induce cardiac arrest.3)Healthcare workers should wear personal protective equipment(PPE).4)Mouth-to-mouth ventilation should be avoided on patients suspected of having or diagnosed with COVID-19.5)Hands-only chest compression and mechanical chest compression are recommended.6)Tracheal-intubation procedures should be optimized and tracheal-intubation strategies should be implemented early.7)CPR should be provided for 20-30 min.8)Various factors should be taken into consideration such as the interests of patients and family members,ethics,transmission risks,and laws and regulations governing infectious disease control.Changes in management:The following changes or modifications to CPR strategy in COVID-19 patients are proposed:1)Healthcare workers should wear PPE.2)Hands-only chest compression and mechanical chest compression can be implemented to reduce or avoid the spread of viruses by aerosols.3)Both the benefits to patients and the risk of infection should be considered.4)Hhealthcare workers should be fully aware of and trained in CPR strategies and procedures specifically for patients with COVID-19.展开更多
基金Project(2013DFA5129)supported by the International Science and Technology Cooperation Program of China
文摘Large scaled uniform and size-controllable magnetic submicroparticles(MSPs) were synthesized via solvothermal method with ferric chloride as iron source and sodium acetate as trapping agent. The influence of Fe^(3+) and Na Ac contents on the size distribution of MSPs was investigated. The structural and morphological properties of the synthesized particles were studied by scanning electron microscopy(SEM), X-ray power diffraction(XRD) and vibrating sample magnetometer(VSM). The well-dispersed MSPs with size of 100-1000 nm were obtained by simply adjusting the contents of Fe^(3+) and NaA c. In addition, the hemolysis and cytotoxicity of Fe_3O_4 MSPs, and their ability to case arrest in cell life-cycles were studied. The results indicate that larger size could lead to lower hemolysis. From MTT(3-(4,5-dimethylthuazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, the interactions between MSPs and adhesive mouse fibroblast cell line(L929) were probed. Larger size of Fe_3O_4 MSPs demonstrates lower cell viability following an exposure to the cells.
文摘Background:Cardiopulmonary resuscitation(CPR)strategies in COVID-19 patients differ from those in patients suffering from cardiogenic cardiac arrest.During CPR,both healthcare and non-healthcare workers who provide resuscitation are at risk of infection.The Working Group for Expert Consensus on Prevention and Cardiopulmonary Resuscitation for Cardiac Arrest in COVID-19 has developed this Chinese Expert Consensus to guide clinical practice of CPR in COVID-19 patients.Main recommendations:1)A medical team should be assigned to evaluate severe and critical COVID-19 for early monitoring of cardiac-arrest warning signs.2)Psychological counseling and treatment are highly recommended,since sympathetic and vagal abnormalities induced by psychological stress from the COVID-19 pandemic can induce cardiac arrest.3)Healthcare workers should wear personal protective equipment(PPE).4)Mouth-to-mouth ventilation should be avoided on patients suspected of having or diagnosed with COVID-19.5)Hands-only chest compression and mechanical chest compression are recommended.6)Tracheal-intubation procedures should be optimized and tracheal-intubation strategies should be implemented early.7)CPR should be provided for 20-30 min.8)Various factors should be taken into consideration such as the interests of patients and family members,ethics,transmission risks,and laws and regulations governing infectious disease control.Changes in management:The following changes or modifications to CPR strategy in COVID-19 patients are proposed:1)Healthcare workers should wear PPE.2)Hands-only chest compression and mechanical chest compression can be implemented to reduce or avoid the spread of viruses by aerosols.3)Both the benefits to patients and the risk of infection should be considered.4)Hhealthcare workers should be fully aware of and trained in CPR strategies and procedures specifically for patients with COVID-19.