王某，女，23岁。受凉后突然出现寒战，高热、咳嗽，咳铁锈色痰，胸痛。查体：叩诊右下肺

下列哪项不是分泌性腹泻的特点

A．肠黏膜组织学基本正常

B．肠液与血浆渗透压相同

C．禁食不减轻腹泻，也不加重腹泻

D．常伴有肠鸣音亢进和腹痛

E．粪呈水样，量大，无脓血或脂肪过多

（）是由8个葡萄糖分子形成的环状低聚糖化合物。

A．乙基化β环糊精衍生物 

B．羟丙基β环糊精 

C．丁环糊精 

D．β环糊精 

E．α环糊精

电影《曼陀罗》的姊妹片是（）

A、《悲歌一曲》

B、《上升》

C、《种女》

D、《春香传》

二次气泡产生的原因是什么？

Networks can be interconnected by different devices. In the physical layer, networks can be connected by (1) or hubs, which just move the bits from one network to an identical network. One layer up we find bridges and switches, which operate at data link layer. They can accept (2) , examine the MAC address, and forward the frames to a different network while doing minor protocol translation in the process. In the network layer, we have routers that can connect two networks. If two networks have (3) network layer, the router may be able to translate between the packet formats. In the transport layer we find transport gateway, which can interface between two transport connections. Finally, in the application layer, application gateways translate message (4) . As an example, gateways between Internet e-mail and X.400 e-mail must (5) the e-mail message and change various header fields.

A．frames

B．packets

C．packages

D．cells