Recently, Baidu chief scientist Wu Enda gave a speech on artificial intelligence. He said that artificial intelligence is now entering a period of rapid development, which will change society and life in the fields of medical care , consumer finance, anti-cheating, education and logistics optimization. Wu Enda also emphasized that he is very optimistic about the application of artificial intelligence in the fields of companion robots and robot doctors. What magic power does the robot doctor have, so that Wu Enda is so respected? Some time ago, a surgical robot named "Da Vinci" smashed the topic of the Internet. It is understood that from September 2014, the First Affiliated Hospital of Zhejiang University School of Medicine introduced the "Da Vinci" robot, as of 2016. On July 10th, the Department of Urology, Zhejiang University, Department of Urology, Da Vinci robot surgery has exceeded 1,000 cases. As more and more people understand "Da Vinci", the burden of complicated surgery such as urology, hepatobiliary surgery, gastrointestinal surgery, general thoracic surgery, cardiothoracic surgery, gynecology, kidney disease, etc., is gradually falling on this robot. . The Da Vinci robot has already made people feel amazing, but this surgical robot, which is a model worker in the medical profession, is less autonomous than a "resource nurse." There is a very interesting piece of information recently. Researchers at the Massachusetts Institute of Technology have developed the latest interactive robots that are well qualified for the role of “resource nurses†and provide advice to healthcare professionals to help them make decisions in complex situations. The robot helps the doctor make a decision, reminiscent of the omnipotent Doraemon. But this robot is much more powerful than the Doraemon. According to news reports, the robot's mission is to be responsible for making decisions on thousands of important issues, including bed allocation and selecting the right nurse for cesarean section. As of now, the researchers found that the adoption rate of robots recommended by medical staff during this period was as high as 90%. Since the treatment plan proposed by the robot-assisted doctor for the patient has come true, will there really be a robot hospital operating in the future? Although I don't know when this illusion can be achieved, it is certain that it is not far from the time when the robot is sitting on the doctor and helping the patient confirm that the illness has become a reality. Recently, Google’s futurist Kozwell’s assertion about “nano-robots†sparked heated debate. But in fact, as early as 2010, American scientists developed a nano-spider robot composed of DNA, which is only 4 nanometers long and smaller than one hundred thousandth of the diameter of human hair. It can be activated and moved according to the trajectory of DNA. , Steering and Stopping, scientists can program to identify cancer cells and control nano-spiders to kill cancer cells. It is believed that in the next few years, nano-robots are likely to bring about a medical revolution that will unleash enormous potential in anti-cancer, blood clot removal, wound cleaning, gout treatment, and crushing of stones.
Amino acids are colorless crystals with a melting point of more than 200℃, much higher than that of ordinary organic compounds. α -amino acids have sour, sweet, bitter and fresh taste. Monosodium glutamate and glycine are the most used umami flavoring ingredients. Amino acids are generally soluble in water, acid and alkali solutions, insoluble or slightly soluble in organic solvents such as ethanol or ether. The solubility of amino acids in water varies greatly. For example, tyrosine has the lowest solubility. At 25℃, only 0.045g of tyrosine dissolved in 100g of water, but the solubility of tyrosine is greater in hot water. Lysine and arginine often exist in the form of hydrochloride, because they are easily soluble in water and difficult to crystallize due to deliquescence
(1) Color and color: all kinds of common amino acids are easy to become colorless crystals, and the crystal shape varies with the structure of amino acids. For example, L-glutamic acid is a quadrangular column crystal, and D-glutamic acid is a diamond flake crystal.
(2) Melting point: the melting point of amino acid crystallization is high, generally at 200 ~ 300℃, and many amino acids will decompose into amine and CO2 when reaching or approaching the melting point.
(3) Solubility: Most amino acids are soluble in water. The solubility of different amino acids in water is different, such as lysine, arginine, proline solubility is larger, tyrosine, cysteine, histidine solubility is very small. Various amino acids are soluble in strong bases and acids. But amino acids are insoluble or slightly soluble in ethanol.
(4) Taste sensation: Amino acids and their derivatives have certain taste sensation, such as sour, sweet, bitter and salty. The kinds of taste are related to the kinds and stereoscopic structure of amino acids. Generally speaking, d-type amino acids have sweet taste, and their sweet taste intensity is higher than the corresponding L-type amino acids.
(5) UV absorption characteristics: all kinds of common amino acids have no absorption ability to visible light. But tyrosine, tryptophan and phenylalanine have obvious light absorption in uv region. These three amino acids are found in most proteins, especially tyrosine. Therefore, the uv absorption characteristics at 280nm can be used to quantitatively detect protein content.
An important optical property of amino acids is their absorption of light. All 20 kinds of PR-Aa have light absorption in visible region, and all have light absorption in far ULTRAVIOLET region (<220nm). Only three kinds of AA have light absorption ability in ultraviolet region (near ultraviolet region) (220nm ~ 300nm). These three kinds of amino acids are phenylalanine, tyrosine and tryptophan, because their R group contains benzene ring conjugated double bond system.
The maximum light absorption of phenylalanine AA is 259nm, the maximum light absorption of tyroaa is 278nm, and the maximum light absorption of chroma AA is 279nm. Protein generally contains these three AA residues, so its maximum light absorption is about 280nm wavelength, so it can be used to easily determine the content of protein. Spectrophotometric determination of protein content is based on lambert-Beer law. The absorbance value of protein solution at 280nm is proportional to its concentration.
Amino acids, basic amino,acidic carboxyl Shaanxi Kepler Biotech Co.,Ltd , https://www.keplerherb.com