肝功能障碍发生肠源性内毒素血症的基本原因是（） A.通过肝窦的血流减少 B.肝脏免疫

The teacher said that ____________________.

A．light travel much faster than sound

B．light travelled much faster than sound

C．light had travelled much faster than sound

D．light travels much faster than sound

._________alone in the large house, the little boy had to learn to survive by himself.

A．To leave

B．Leaving

C．Left

D．Being left

报请类文件的写作特点是什么？

女性，32岁，发现右乳多发肿块伴疼痛2年,症状在月经前加重，月经后疼痛逐渐缓解、肿块消失，最可能的诊断是

A．右侧乳癌

B．乳腺囊性增生

C．乳腺脂肪坏死

D．浆细胞性乳腺炎

E．乳腺纤维腺瘤

简述内生宝石矿床。