【单选题】从水中萃取水溶性生物碱所采用的溶剂是( )
【单选题】女性,23岁,既往无心脏病史,流产后一周,出现急性细菌性心内膜炎,伴二尖瓣关闭不全的症状及体征,血培养有粪链球菌生长,最适宜的治疗为
D.
静点氨苄青霉素,每天12g,庆大霉素3mg/(kg•d),持续4周
E.
静点万古霉素,每天1g,持续4周,链霉素每天1g,用2周
【单选题】What is the purpose of a network mask?()
A.
It is used in conjunction with the wildcard mask to determine the number of hosts on a network
B.
It is used to define which parts of the IP address are allocated to host addresses and network prefixes
C.
It is used to hide subnets from external networks by masking the subnets with NAT
D.
It is used to differentiate a network as a classful network or a classless network
【简答题】Unknown to most Facebook users, the social network actually offers a lot of privacy controls and security features which can help you lock your account, so you can speak freely. If it’s used properly,...
【单选题】In a type of computer network, what does MAN stands for?
C.
Metropolitan area network
【单选题】What is the goal of QoS in a network? ()
A.
prevent packets from being dropped
B.
increase available bandwidth
C.
reduce hardware errors
D.
provide predictable network service
E.
eliminate propagation delay
F.
eliminate jitter and packet loss