【多选题】CTLs are cytotoxic against tumor cells and host cells infected with intracellular pathogens. These cells usually express ____ and destroy infected cells in an antigen-specific manner that is dependent...
【单选题】In the brain, only __________ of the nervous system that provide nutrients, support, and insulation for neurons—express glutamine synthetase.
【多选题】下面关于unix的描述正确的是()
C.
使用chmod777可以改变文件访问权限为属主、用户组、其他人都可读可写可执行
D.
使用chmod ugo+rwx abc.c表示改变文件abc.c访问权限为属主、用户组、其他人都可读可写可执行
【判断题】Female mammals that are heterozygous for an X-linked gene have patches of cells that express one allele and patches of cells that express the other.
【单选题】下列说法不正确的有( )
A.
集成温度传感器把热敏晶体管和外围电路、放大器、偏置电路及线性电路制作在同一芯片上,构成一体化的专用集成器件.
B.
集成温度传感器测温范围受半导体材料的极限工作温度限制。
C.
集成温度传感AD590器是把温度的变化转换为线性电压的变化。
D.
数字集成温度传感DS18B20器内部有A/D转换电路,输出为数字信号。
【单选题】Cells that express both CD3 and CD8 are
【单选题】In ______, Theodore Friedmann and Richard Roblin published an important paper in Science [175(4025): 949-955] describing the use of gene therapy. Friedmann and Roblin described how they induced mammal...
【多选题】大气中NO,NO2和O3之间存在着的化学循环是大气光化学反应的基础,下面那些化学反应与之相关。
【判断题】如图中3504.700加上括号的意思是该材料为矩形梁混凝土的原材料,其单价已经计入混凝土单价中,所以为括号