Human tears could carry a flood of useful information. With just a few drops, a new technique can spot eye disease and even glimpse signs of diabetes(糖尿病), scientists report in ACS Nano.

“We wanted to demonstrate the potential of using tears to detect disease,” says Liu Fei, a biomedical engineer at Wenzhou Medical University in China. It's possible that the t cars could open a window for scientists to look into the entire body, he says, and one day even let people quickly test their tears at home.

Tears contain tiny sacs(囊) stuffed with cellular(细胞的) messages. If scientists could capture these microscopic mail bags, they could offer new information on what's happening inside the body.

But collecting enough of these sacs is tricky. Unlike fluid from other body parts, just a trickle of liquid leaks from the eyes.

So Liu's team invented a new way to get the sacs from tiny volumes of tears. First, the researchers collected tears from study participants. Then, the team added a solution containing the tears to a device with two nanoporous membranes(纳米多孔膜), shook the membranes and sucked the solution through. Within minutes, the technique lets small molecules(分子) escape, leaving the sacs behind for analysis. The result surprises scientists very much. Different types of dry-eye disease left their own molecular fingerprints in people's tears, the team found. What's more, tears could potentially help doctors monitor how a patient's diabetes is progressing.

Now, the scientists want to make use of tears for evidence of other diseases as well as depression or emotional stress, says study coauthor Luke Lee, a bioengineer at Harvard Medical School. “This is just the beginning.” he says, “Tears express something that we haven't really explored.”

【小题1】Which of the following can provide some information on the inside of the body?

A．Tiny sacs.	B．Body fluid.
C．Molecular fingerprints.	D．Nanoporous membranes.

【小题2】What does paragraph 4 mainly talk about?

A．A new way to make sacs.	B．Procedures of obtaining sacs.
C．The cause of the experiment.	D．Hope for diabetes patients.

【小题3】What can we infer from the last paragraph?

A．Further research on tears is to be made by scientists.

B．Scientists have discovered more evidence about tears.

C．Scientists have done more than enough research on tears so far.

D．Scientists merely use t cars as evidence of mental problems.

【小题4】Where docs the text probably come from?

A．An official document.	B．A personal blog.
C．A fashion journal.	D．A science report