Blood / Кровь
The term artificial blood is somewhat misleading. There is no one product that is being designed to replace the function of human blood. There are two main categories; which consist of volume expanders, which only increase blood volume, and oxygen therapeutics, which substitute for the bloods natural ability to carry oxygen.
We need blood substitutes due to increasing demands. According to the American Red Cross blood donation is increasing 2-3% annually in the United States, but the demand steadily is climbing by between 6-8%. The demand is climbing due to the fact that our population is aging and more operations are involving the use of blood and blood transfusions.
Another reason for increasing demands is due to developing nations. Appropriately 10-15 million units of blood are transfused each year without testing for HIV or hepatitis. Blood transfusion is the second largest source of the new HIV infections in Nigeria. A disease free blood substitutes would be so beneficial in these regions. Hemopure is currently approved for use in South Africa.
The United States Army is where the first research into producing blood substitutes was conducted following the Vietnam War. When you are out on the battlefield the armed forces would definitely benefit from blood substitutes because there are dire needs when time is of the essence and typing blood is not on the priority list when it is life or death.
Hemospan is a blood substitute that can be dried and transported as a powder, stored for years and then reconstituted as liquid before transfusion. This would have been tremendous implication for the military as it would be very easy to administer. Hemospan does not even require typing. There are other types of blood substitutes in the working as well such as HemoTech that eliminates the need to match blood types between patients and donors, because pure hemoglobin is not affected by varying factors found in human blood. In addition, HemoTech has a shelf life of at least 180 days—significantly longer than the typical 42-day period during which donated blood can be used.
I was able to speak with the 433rd Chief of Medical Operations located at Lackland Air Force Base, San Antonio, Texas and he was explaining to me how the military has a vested interest in the success of blood substitutes. During our conversation he spoke to me on the safety of blood substitutes. During HIV infection test results can be negative, as antibodies may not have formed. Blood substitutes could lower the number even more.
Last year I tried donating blood, but I spent time in England and due to Mad Cow’s disease I was unable to donate. Currently there is no way to test for Mad Cow, Smallpox and other diseases so the blood supply has been decreasing. Just think of all the people that could donate blood if there were other means of testing.
Last, but not least blood substitutes could be cheaper. Current range of blood substitutes range between 300 to 1000 dollars. The region is a determination of the cost as well. The cost of blood substitutes will fall, as manufacturing is refined. The cost of storage and administrative cost will lessen. Also where there is two or three units of blood needed there would only be a need of one blood substitute so that would cut back on price making price less significant.
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