Human bones change dynamically.For a human,bones usually start to form at the 7thweek of the embryonic period and continue to develop until the human has reached skeletal maturity.During this stage of development,them...Human bones change dynamically.For a human,bones usually start to form at the 7thweek of the embryonic period and continue to develop until the human has reached skeletal maturity.During this stage of development,themass,density,morphology,hardness and strength of human bones are constantly changing.There are studies that describe the dynamic changes in bone morphology in each part of the human body from the embryonic period to puberty.For example,the femoral neck torsion angle(FNTA)is approximately 30 to 40 degrees at birth,and the angle gradually recedes to 10 to 15 degrees by early adolescence.Infants have a large femoral neck-shaft angle(NSA),and this angle decreases gradually to an angle common in adults.Recent studies have focused on the physiological and molecular mechanisms by which bones sense,transduce,and respond to mechanical loads and have investigated the effects of aging processes on the relationship between cortical bone properties(such as cross-sectional geometry and bone mineral density)and mechanical function.[1,2]展开更多
Since December 2019,many patients in Wuhan sustained pneumonia with unknown causes.[1,2]A part of severe patients developed acute respiratory distress syndrome or septic shock,and even death.On January 7,2020,Chinese ...Since December 2019,many patients in Wuhan sustained pneumonia with unknown causes.[1,2]A part of severe patients developed acute respiratory distress syndrome or septic shock,and even death.On January 7,2020,Chinese researchers have for the first time detected a new coronavirus.On January 20,2020,the National Health Commission issued Announcement No.1 of 2020,which included the new coronavirus pneumonia as a Class B infectious disease,and conducted epidemic prevention and control according to the Class A infectious disease.This new kind of pneumonia has been named coronavirus disease 2019(COVID-19).The sixth edition of"Diagnosis and Treatment Scheme for New Coronavirus Infected Pneumonia"points out that the main transmission routes include respiratory droplets and close contact transmission.There is a possibility of aerosol transmission in a relatively closed environment with prolonged exposure to high concentrations of aerosol.New coronavirus pneumonia has a certain incubation period.展开更多
文摘Human bones change dynamically.For a human,bones usually start to form at the 7thweek of the embryonic period and continue to develop until the human has reached skeletal maturity.During this stage of development,themass,density,morphology,hardness and strength of human bones are constantly changing.There are studies that describe the dynamic changes in bone morphology in each part of the human body from the embryonic period to puberty.For example,the femoral neck torsion angle(FNTA)is approximately 30 to 40 degrees at birth,and the angle gradually recedes to 10 to 15 degrees by early adolescence.Infants have a large femoral neck-shaft angle(NSA),and this angle decreases gradually to an angle common in adults.Recent studies have focused on the physiological and molecular mechanisms by which bones sense,transduce,and respond to mechanical loads and have investigated the effects of aging processes on the relationship between cortical bone properties(such as cross-sectional geometry and bone mineral density)and mechanical function.[1,2]
文摘Since December 2019,many patients in Wuhan sustained pneumonia with unknown causes.[1,2]A part of severe patients developed acute respiratory distress syndrome or septic shock,and even death.On January 7,2020,Chinese researchers have for the first time detected a new coronavirus.On January 20,2020,the National Health Commission issued Announcement No.1 of 2020,which included the new coronavirus pneumonia as a Class B infectious disease,and conducted epidemic prevention and control according to the Class A infectious disease.This new kind of pneumonia has been named coronavirus disease 2019(COVID-19).The sixth edition of"Diagnosis and Treatment Scheme for New Coronavirus Infected Pneumonia"points out that the main transmission routes include respiratory droplets and close contact transmission.There is a possibility of aerosol transmission in a relatively closed environment with prolonged exposure to high concentrations of aerosol.New coronavirus pneumonia has a certain incubation period.
