Birds lack surfactant protein D (SP-D), a key immune molecule found in mammals that helps fend off airborne pathogens. Instead, they rely on ancient proteins called CL-10 and CL-11, which have been ...

尹同跃说的英语你懂了吗？ 小时候：good good study day day up 现在中国汽车是day day up！

In recent years, Shanxi has made great efforts to protect and study the grottoes. In 2021, the research institute of the ...

DK 终级学习指南 DK The Ultimate Bitesize Study Guide 共4本 英文版PDF 数学/物理/化学/生物 DK 终级学习指南 DK The Ultimate Bitesize Study Guide ...