Friday, March 20, 2020

Prolonged Preservation of the Heart Prior to Trans Essays

Prolonged Preservation of the Heart Prior to Trans Essays Prolonged Preservation of the Heart Prior to Transplantation Biochemistry Prolonged Preservation of the Heart Prior to Transplantation Picture this. A man is involved in a severe car crash in Florida which has left him brain-dead with no hope for any kind of recovery. The majority of his vital organs are still functional and the man has designated that his organs be donated to a needy person upon his untimely death. Meanwhile, upon checking with the donor registry board, it is discovered that the best match for receiving the heart of the Florida man is a male in Oregon who is in desperate need of a heart transplant. Without the transplant, the man will most certainly die within 48 hours. The second man's tissues match up perfectly with the brain-dead man's in Florida. This seems like an excellent opportunity for a heart transplant. However, a transplant is currently not a viable option for the Oregon man since he is separated by such a vast geographic distance from the organ. Scientists and doctors are currently only able to keep a donor heart viable for four hours before the tissues become irreversibly damaged. Because of this preservation restriction, the donor heart is ultimately given to someone whose tissues do not match up as well, so there is a greatly increased chance for rejection of the organ by the recipient. As far as the man in Oregon goes, he will probably not receive a donor heart before his own expires. Currently, when a heart is being prepared for transplantation, it is simply submerged in an isotonic saline ice bath in an attempt to stop all metabolic activity of that heart. This cold submersion technique is adequate for only four hours. However, if the heart is perfused with the proper media, it can remain viable for up to 24 hours. The technique of perfusion is based on intrinsically simple principles. What occurs is a physician carefully excises the heart from the donor. He then accurately trims the vessels of the heart so they can be easily attached to the perfusion apparatus. After trimming, a cannula is inserted into the superior vena cava. Through this cannula, the preservation media can be pumped in. What if this scenario were different? What if doctors were able to preserve the donor heart and keep it viable outside the body for up to 24 hours instead of only four hours? If this were possible, the heart in Florida could have been transported across the country to Oregon where the perfect recipient waited. The biochemical composition of the preservation media for hearts during the transplant delay is drastically important for prolonging the viability of the organ. If a media can be developed that could preserve the heart for longer periods of time, many lives could be saved as a result. Another benefit of this increase in time is that it would allow doctors the time to better prepare themselves for the lengthy operation. The accidents that render people brain-dead often occur at night or in the early morning. Presently, as soon as a donor organ becomes available, doctors must immediately go to work at transplanting it. This extremely intricate and intense operation takes a long time to complete. If the transplanting doctor is exhausted from working a long day, the increase in duration would allow him enough time to get some much needed rest so he can perform the operation under the best possible circumstances. Experiments have been conducted that studied the effects of preserving excised hearts by adding several compounds to the media in which the organ is being stored. The most successful of these compounds are pyruvate and a pyruvate containing compound known as perfluoroperhydrophenanthrene-egg yolk phospholipid (APE-LM). It was determined that adding pyruvate to the media improved postpreservation cardiac function while adding glucose had little or no effect. To test the function of these two intermediates, rabbit hearts were excised and preserved for an average of 24.5 1 0.2 hours on a preservation apparatus before they were transplanted back into a recipient rabbit. While attached to the preservation apparatus, samples of the media output of the heart were taken every 2 hours and were assayed for their content. If the compound

Wednesday, March 4, 2020

Order Professional Help Annotated Bibliography Examples

Order Professional Help Annotated Bibliography Examples Annotated bibliography is a combination of the research materials citations and their summaries. It is one of the elements of a good APA, MLA or Chicago style paper. If you are searching for the examples of annotated bibliography here is a collection of samples of annotated bibliography: Chicago Style, MLA, APA. If you dont have time to write it on your own, you may read: HOW TO BUY ANNOTATED BIBLIOGRAPHY ONLINE What is an Annotated Bibliography? An annotated bibliography is a list of research materials - books, articles, and documents  - presented both as citations  and as a summary of their value. The description acts to evaluate the source as a credible document. The purpose of the annotated bibliography is to inform the reader of the relevance, accuracy, and quality of the sources cited. Annotated bibliographies are different from abstracts, the latter being purely descriptive summaries found at the beginning of scholarly journal articles, while annotations are descriptive and require critical thinking. They may take into account the authors point of view, authority, and the place and time of their piece. How to Write an Annotated Bibliography Step 1.  Choose works that provide a balanced perspective on your topic. Step 2.  Locate and cite the books, periodicals, and documents about your topic. Step 3.  Cite the source using the appropriate style for your paper: MLA, APA or Chicago Manual Style. Step 4.  Write a concise annotation that summarizes the central theme and scope of the book or article. Include one or more sentences that accomplish one of the following: qualify the authority of the author; comment on who might gain from reading this source; compare the work to other work being cited; or, explain how this work enlightened you on your topic. Step 5.  Sign up today for the annotated bibliography writing service that will change the way you finish your school assignments. Sample MLA Annotation Greene, Robert. The 48 Laws of Power. Penguin Books, 2000. Greene offers honest advice on how to conduct ones life, according to the lessons we have learned from history, its rulers and their failures. Taking a sometimes fantastical approach to the realities of societal rules and norms, the chapters in Greenes book are wry and anecdotal and offer advice on everything from avoid the unhappy and the unlucky and mastering the art of timing. In the process, Greene includes interpretations of each law and examples of when the law was carried out in reverse to someones detriment. Greene offers sober, although harsh, advice for those struggling with ones imperfect journey with flawed peers, unfair laws, and conniving rivals. Rather than a practical handbook to how to live ones life, this text takes an honest perspective with advice that only those who truly need power will end up being able to implement in their life. However, there is still some useful tips that us every man and every woman can take. Chapters in this text lend themselves to being studied out of order, or as they become necessary in the readers life. Some of the chapters would even do well as part of a history course, or a section of a course, where students were learning about the human spirit and human folly. See also: MLA Essay Format with Example Sample APA Annotation Camron, J. (1992). The Artists Way. New York: Tarcher Putnam. In this workbook of nonfiction based on the writers creative journey, Cameron attempts to guide readers through the stages of reclaiming their inner artist and bringing more art into their lives. She does so by implementing the discipline of writing morning pages each day and by answering open-ended questions throughout to help the reader gauge where and why they may be stuck creatively. An experienced writer, Cameron is aware of the limitations of her experiment, and thats why she uses this book in tandem with live talks and workshops and encouraging fans of her work to meet where they live and help each other operate more like artists. The author is forthcoming about her past struggles with alcohol and the frustrations in her shortcomings as a poet to help ease the pretense that artists are artists and those who are not yet artists are on the outside looking in. Camerons book is completely inclusive and seems to embrace all who dare to discover their dormant inner artist. See also: APA Citation Machine Referencing Format Tool Sample Chicago Style Annotated Bibliography Schwabs book provides a thorough examination of the current state of Africas countries, communities, wars, resources, and leaders and how things came to be, from colonization until the new millennium. The author discusses relevant topics, such as war, cross-border conflict, ethnic conflict, despotic leadership, predatory regimes, and economic health. The book includes chapters on the slave trade, AIDS and poverty, globalization, and a question that asks if the continent will survive. This book could be read as part of a course but it appears the intention of the writer was to create a book for the interested layman to get a brief and terrifying history lesson. See also: Chicago Style Format with Example We hope, youve found these annotated bibliography samples helpful. Use them as the examples when composing your annotated bibliography. If you have no time for writing your APA annotated bibliography or MLA annotated bibliography, etc., you may order it online.  Place an order for annotated bibliography writing help, saying write me annotated bibliography, and we will deliver to you an expertly-presented piece. If you need any other writing services, feel free to contact our writers for assistance.