Chapter 729 One sentence, a dead end
Inside the First Research Building, Lahar also knew about Xu Qiu's news.
But he didn't pay too much attention.
The surgery competition itself was his weak point, and the current scientific research competition was the real focus.
The scientific research project given to him by the Meiguo Medical Research Institute was almost at the limit of the existing scientific and technological strength, and it was difficult to lose.
He didn't take Xu Qiu seriously at all.
"Go on."
Lahar's attention returned to the laboratory and he focused again.
...
In the following day, Xu Qiu's energy was also focused on the preparation of the fully magnetically suspended artificial heart.
"The flow rate of the artificial heart pump needs to be controlled at 0~10L per minute, and the head is 80 to 120mmHg..."
"In terms of hemolytic performance, NIH must be less than about 0.008g per 100L!"
In these days of research, Xu Qiu also obtained more data.
When red blood cells are subjected to shear stress of 0~150Pa, they will gradually change from elliptical to prolate ellipsoid. As long as the exposure time is not long, when the shear stress is removed, the red blood cells will also return to their normal shape.
However, as long as it exceeds 150Pa, the incidence of hemolysis will greatly increase.
As for exceeding 1000Pa, severe hemolysis will break out within a few milliseconds.
Based on various data, the preliminary design has been finalized.
The artificial heart has three main parts.
The first is the impeller part.
In the traditional impeller structure, due to the high-speed rotation of the blades, the red blood cells are exposed to shear stress, and the probability of hemolysis is very high...
Therefore, Xu Qiu led the team to study the influence of factors such as blade curvature, open impeller and blade outlet width on shear stress, and finally selected the logarithmic spiral blade with the lowest hemolysis value.
After four months of hard work, the preliminary work has been completed, and the six-blade spiral structure has won with the smallest stagnation area, the lowest stress level and the highest strain rate.
Of course, these are just for Miaoyou's staff to see.
In fact, after Xu Qiu's design and improvement, the twelve-blade pump has a more stable performance under high-speed rotation...
...
The second point is the design and structure of the volute part.
The volute is the most important flow-through component in the centrifugal pump.
Xu Qiu chose a circular cross section from dozens of volute cross sections and introduced a new structure, the volute tongue.
This device can improve the efficiency of the pump.
Of course, all of this is based on a heart with a perfect impeller structure.
Xu Qiu's real achievement is a fully magnetically suspended heart.
And this technology was split by Xu Qiu into another experimental team. Until now, the two teams did not know that they were actually studying the same thing...
"Done."
Two weeks later, on a quiet afternoon, Xu Qiu gradually dismantled the mechanical bearings, seals, valves and other parts in the heart pump.
He used a magnetic coupling drive method to arrange the driving magnet and the secondary moving magnet in the radial direction. The motor drives the driving magnet, and the torque is transmitted by magnetic coupling. The driven magnet that receives the magnetic force begins to drive the impeller to rotate.
So far, a generation of fully magnetically suspended artificial hearts has come out.
...
"Then there is a non-invasive prenatal detection method!"
Xu Qiu had also planned this scientific research project.
Compared with the other nine projects, its importance is incomparable.
Applicable to all mankind, once successful, it may change the prenatal testing process in the future, with a profound impact.
From the beginning, Xu Qiu aimed at PCR technology.
During this process, Xu Qiu accidentally found fetal nucleated cells in the maternal circulation.
Other staff members were extremely excited.
There are genetic signals in nucleated cells. If nucleated cells can be analyzed, they can naturally be perfectly competent for non-invasive prenatal testing...
However, Xu Qiu was keenly aware that this was a dead end and directly cut off this road.
And it was not until many years later that Meiguo tried to find another way out of Xu Qiu's heavy confidentiality and find a new means of non-invasive prenatal testing belonging to Meiguo that nucleated cells were picked up again.
It took them seven years and tens of billions of dollars to finally find the problem-
This kind of fetal cell is too rare to obtain reliable and consistent signals!
This means that it cannot be applied to all clinical pregnant women, and it is not an easy task to find nucleated cells that belong to the circulating fetus in the maternal circulation. Even if it can be done, the cost is extremely high.
Seven years later, the scientific research community in Meiguo finally understood how important scientific research talents are. Xu Qiu's casual words saved Daxia Medical from wasting tens of billions of dollars and nearly seven years of time!
…
After the nucleated cells were denied, Xu Qiu and his team fell into a period of confusion for several weeks.
Blind search, no goal.
What inspired Xu Qiu was cancer cells.
As we all know, cancer cells release DNA into the plasma and serum of cancer patients.
Even tiny cancer cells can release DNA, so there is no reason why the huge fetus can not leak at all.
Therefore, Xu Qiu began to look for blood cells.
This is much easier than cancer cells. The blood of pregnant women contains fetal DNA fragments.
Although the fetal DNA in the mother will disappear immediately within two hours after the delivery, this does not affect its application in prenatal diagnosis.
After nearly half a month, Xu Qiu finally found a method for extraction.
He took out the free fetal DNA and then heated the plasma. During this period, all proteins that would affect the DNA test results were inactivated. After centrifugation and extraction, the DNA sample finally obtained successfully detected fetal DNA from maternal plasma!
This method of extracting fetal DNA from the peripheral blood of pregnant women for non-invasive prenatal diagnosis only requires blood drawing, which is extremely safe. It uses the new generation of DNA sequencing technology. With the assistance of PCR, even the smallest amount of DNA fragments can obtain enough genetic information to accurately complete biological analysis and determine whether the fetus has three major chromosomal diseases.
It is extremely safe and has an accuracy rate of more than 99%.
Compared with amniocentesis, which is commonly used in clinical practice today, it can be said to have all-round advantages.
It can be foreseen that when the technology of extracting fetal DNA from the peripheral blood of pregnant women is announced, the world will be shocked, and obstetrics and gynecology prenatal testing will also enter a new era...
...
Then, there is the new sequential ventilation therapy.
This is the experience that Xu Qiu has explored and summarized after dealing with a huge number of acute lung injury, pulmonary embolism and other acute and severe respiratory diseases, which has greatly improved the clinical treatment rate.
In particular, the proposal of the "lung infection window" will become a key node for invasive and non-invasive treatment, and further guide clinical rescue and treatment.
The old treatment strategy is actually very confusing, and it is not clearly mentioned in the clinical guidelines. Different hospitals and different doctors perform rescue according to clinical experience, but the proposal of the new sequential ventilation therapy is very likely to become a new rescue and non-invasive weaning path, and it is listed as one of the clinical bibles.
