桑寄生的功效是（） A.通筋络，强筋骨 B.强筋骨，利水 C.和胃化浊 D.补肝肾，

(66) is used to ensure the confidentiality, integrity and authenticity of the two end points in the private network. (67) , an application-layer protocol, authenticates each peer in an IPsec transaction. IKE negotiates security policy, determining which algorithm may be used to set up the tunnel. It also handles the exchange of session keys used for that one transaction.
Networks that use (68) to secure data traffic can automatically authenticate devices by using (69) , which verify the identities of the two users who are sending information back and forth. IPsec can be ideal way to secure data in large networks that require secure connections among many devices.
Users deploying IPsec can (70) their network infrastructure without affecting the applications on individual computer. The protocol suite is available as a software-only upgrade to the network infrastructure. This alows security to be implemented without costly changes to each computer. Most important, IPsec allows interoperability among different network devices, PCs and other computing systems.

A．IPSec

B．SSL

C．L2TP

D．The Internet Key Exchange

先天性喉喘鸣患儿通常不出现下列哪项症状（）

A.吸气性喉鸣

B.吸气相延长

C.吸气性呼吸困难

D.声音嘶哑

E.阵发性青紫

胎儿娩出后立即出现持续性 * * 流血，色鲜红. 子宫轮廓清楚，应诊断为

A．子宫收缩乏力

B．软产道裂伤

C．胎盘剥离不全

D．胎盘部分粘连

E．凝血功能障碍

铁路中间站停留车辆，无论停留线路是否有坡道，均应连挂在一起，拧紧两端车辆的手制动机，并以( )牢靠固定。

A．千斤顶

B．倒链

C．钢丝绳

D．铁鞋

女，1岁，头大，智力障碍，CT示四脑室与枕大池扩大，小脑蚓部和半球发育不良，幕上脑室扩大。

在影像学表现上，本病主要与下面哪种疾病鉴别

A．先天性脑积水

B．脑裂畸形

C．脑灰质异位

D．颅后窝巨大蛛网膜囊肿

E．胼胝体发育不全