The three children were readmitted to the hospital, but Xu Yan still prescribed tretinoin for them to eat.

But after eating it for a few days, the condition did not improve at all, but became more and more serious.

"Drug resistance has developed, and the drug is not working." Xu Yan frowned.

"What then?" Jiang Nan was anxious, she never thought that the medicine that had been painstakingly made would actually produce drug resistance in just one month, so would she not be able to take it in the future, and the medicine would be useless?

"It is still useful for patients who have not taken it, at least it can temporarily alleviate the condition, but after all, it cannot cure the root cause, and the only way to cure the patient is to develop new drugs." Xu Yan sighed.

"However, we have spent so much time and energy developing this drug, how easy is it to develop a new drug?" Ren Bin said.

"It's really not easy, in fact, the time for our medicine is also shorter, which pharmaceutical company doesn't need a few years to produce new drugs, we are really a little fast, so there are drawbacks." Xu Yan said.

"But the drug is effective at the beginning, which means that the direction is right, there must be a reason for drug resistance, and we can still use this drug as long as we overcome this drug resistance." Jiang Nan said.

Xu Yan nodded, "Jiang Nan is right, if this medicine does not work, it will not have such a good effect at the beginning, which means that the medicine is right, but it is just to solve the problem of drug resistance." ”

"But why does drug resistance arise?" Everyone is thinking about this.

Jiang Nan was very anxious, if this problem was not solved and the child's condition deteriorated, the consequences would be unimaginable.

"Everyone is investigating what causes drug resistance, and first of all, it is definitely too late to develop new drugs." Xu Yan said.

Jiang Nan and Ren Bin both nodded.

Jiang Nan went to the school library to check the materials, but did not get any useful information.

She went to the Beijing City Library again, where there are more foreign books and magazines, and she may be able to find something useful.

When he arrived at the library, Jiang Nan went to the medical book area first, and after looking around, he didn't find what he wanted.

I came to the foreign language book area, where there were all original books and magazines, including the foreign journal "International Medicine" where Jiang Nan published his papers.

Jiang Nan saw that there was a row of "International Medicine" there, which was a monthly magazine, placed in order of month and size.

Jiang Nan reached out to get the latest August issue, but was taken by another person.

When Jiang Nan turned around, he was an old man over half a hundred years old, with a white shirt on his upper body, black pants on his lower body, and glasses.

He took "International Medicine" in his hand and looked at Jiang Nan, "Little comrade, do you want to read it too?" ”

"Well, why don't you look at it first? I'm waiting. Jiang Nan said.

The old man took out the June and July issues, "I'll read these two first, this one for you first?" ”

"Thank you so much!" Jiang Nan smiled and nodded.

The two of them took the magazines and went to the side seating area together, found a table and sat down.

Jiang Nan opened the magazine, looked at the table of contents first, and found a few articles that were somewhat related.

The old man was a little surprised to see Jiang Nan look serious, there are not many people who can read the original books in foreign languages, it seems that she is not struggling at all, but it is rare.

"You're also studying medicine?" The old man asked softly.

"Well, I'm at the Capital Military Medical University." Jiang Nan smiled and replied softly.

"Not bad." The old man nodded, "This article in the July issue "On the Use of All-Trans Tretinoin in Acute Promyelocytic Leukemia" was written by a student from your school, which is very good!" The old man praised.

Jiang Nan smiled, "Thank you for the compliment, I wrote that paper." ”

"You are Jiang Nan?" The old man was taken aback and couldn't help but raise his voice, realizing that this was the library and lowering his voice, "Are you really Jiang Nan?" ”

"It's me!" Jiang Nan smiled, "My mentor is Xu Yan, and I wrote this paper under his guidance and did a lot of experiments before writing it." ”

"Is that really you?" The old man looked at Jiang Nan, "So young, how old are you?" ”

"I'm twenty-one, sophomore." Jiang Nan smiled.

"The afterlife is terrifying." The old man nodded, "If only I had a student like you." ”

"You're also a doctor?" Jiang Nan asked.

The old man nodded, "I'm a professor at Kyoto Medical College, and my surname is Yu." ”

"Hello, Professor Yu!" Jiang Nan nodded, looked at the magazine in his hand, the paper on tumors he was reading was written by a professor surnamed Yu, and couldn't help asking, "You can't be this Professor Yu Wenqian, right?" ”

"It's me!" Professor Yu said with a smile.

"Ah, hello Professor Yu, you wrote this article so well, I was really ...... just now It's a bit of a class to get an axe. Jiang Nan smiled embarrassedly.

"No, don't be modest, it's already remarkable that you can write such a paper at your age, I'm a few rounds older than you, and I don't dare to rely on the old and sell the old." Professor Yu laughed, seeing that Jiang Nan was so talented and humble, he liked it very much.

"Is there something wrong with it? If you trust me, we can talk about it together. Professor Yu said.

Jiang Nan thought for a while and nodded, "That's right, our drug is now in the clinical trial stage, and the patient has started to be very effective with the drug, but after a month, he has developed drug resistance, and it won't work if he takes it again, I don't know what the reason is and how to solve it." ”

"Oh? So that's the case? Professor Yu groaned.

"I see that in your paper on the treatment of tumors, there is a method of 'cancer cell induction differentiation', what is it specifically, I think it can be used in our medicine, strictly speaking, leukemia is also a kind of cancer." Jiang Nan said.

Professor Yu nodded, "This 'cancer cell induced differentiation' mainly uses arsenite injection. ”

Professor Yu saw that Jiang Nan didn't seem to react for a while, and said: "Arsenic acid injection is arsenic trioxide. ”

"Isn't arsenic trioxide arsenic?" Jiang Nan was taken aback.

"Yes, it's arsenic." Professor Yu smiled, "Adding this reagent to medicine has a unique dual effect on cancer cells. Different concentrations may cause cancer cells to induce differentiation and may also lead to apoptosis. ”

"The addition of arsenic trioxide to the drugs used to treat tumors has reduced the cure rate, but there is no problem of drug resistance." Professor Yu said.

"Really?" Jiang Nan was overjoyed, "Then can I also add arsenic trioxide to my all-trans retinoin?" ”

"You can try." Professor Yu replied with a smile.

"Thank you so much!" Jiang Nan was ecstatic, if the problem of drug resistance was solved, would the children be saved?

Jiang Nan stood up suddenly, and couldn't wait to go back to the experiment, "This magazine...... I ......" She wanted to say that she wanted to borrow it and look at it, but she had already said that she would give it to Professor Yu after reading it, but she was embarrassed.

"You can borrow it first, I'll take a look at these two copies first, and take a good look at your paper." Professor Yu said with a smile.

"Thank you so much." Jiang Nan stood up and bowed to Professor Yu, "When the medicine is successful, I will definitely visit you another day." ”

"Welcome!" Professor Yu also stood up, this young man is good.