国际杂志Cell Systems上刊登了来自美国加州大学旧金山分校的一项研究成果,科研人员利用蓝色光脉冲开启了一种名为Brn2的基因,当Brn2信号足够强时,干细胞就会快速转化为神经元。下列有关分析错误的是()
A.该实验证明了蓝色光脉冲可以促使干细胞分化为神经元
B.蓝色光脉冲使Brn2基因的碱基序列发生了改变
C.rn2基因在神经细胞的形成过程中具有重要作用
D.干细胞和神经元这两种细胞中,蛋白质的种类不完全相同
B、蓝色光脉冲使Brn2基因的碱基序列发生了改变
A.该实验证明了蓝色光脉冲可以促使干细胞分化为神经元
B.蓝色光脉冲使Brn2基因的碱基序列发生了改变
C.rn2基因在神经细胞的形成过程中具有重要作用
D.干细胞和神经元这两种细胞中,蛋白质的种类不完全相同
B、蓝色光脉冲使Brn2基因的碱基序列发生了改变
A.某公司项目邀请3个以上公司招标
B.企业在当地报纸上刊登了招标公告
C.评标期间,招标方使用了8名评标专家,其中技术、经济专家各一名
D.招标方将中标结果通知了投标人,同时将结果告知其他未中标的投标人
【A popular service that has attercted the interest of companies and has home users alike is the sending of voice signals over an IP-based network, such as the Internet. The practice of making telephone calls over the internet has had a number of different names, including packet voice, voice over packet, voice over the internet, internet telephone, and Voice over Ip(Voip). But it appears the industry has settled on the term”Voice ove IP” in reference to the internet protocol, which controls the transfer of data over the internet. There are currently three ways to deliver VoIp to users, the first technique is found at the corporate level. Many companies are offering VoIP systerms that operate over a local area network. These systems involve a fair amount of equipment, such as VoIP servers, special IP-enabled telephones, and routers that can direct telephone calls. Today a large portion of corporate sites have converted their older internal telephone systems to VoIP systems that opreate over a LAN, thus converging two systems into one. A second common solution is the one often encountered at home. Using existing telephones, a special converter is added between the telephone and a high speed internet(DSL or cable modem)connection. The converter digitizes the voice signal and creates a stream of packets that are then sent over an ip connection.The third technique involves smart cell phones. Never cell technologies are all packet-based, thus requiring a telephone call to be converted to digital packets and sending those packets over IP networks.】
From the paragraph above,a popular service that has attracetd the interest of companies and home users,is termed as () . The data transfer over the Internet is controlled by the () . At corporate level, many companies have replaced their older internal telephone systerms with () that oprerate over a local area network.
A、voice over the internet B、voice over packet C、Voice over IP D、internet telephony A、packet B、internet protocol C、industry D、VoIp servers A、VoIP systems B、IP-enablde telephones C、VoIP servers D、routers
A.清朝君主专制独裁
B.各派军阀拥兵割据
C.袁世凯称帝的图谋
D.列强侵犯中国主权
从下列列举的传播方式中,选择最适合此次活动的传播方式()
A.召开座谈会
B.小组讨论
C.播放电影
D.出版板刊、杂志
E.印发传单
A.确立了尊重、有利、公正三项基本原则
B.成为第一部规范涉及人类受试者研究国际伦理准则
C.对行医与科研进行了区别
D.提出对自主性削弱人提供额外保护