lecture 10 medicine in the 20 th century. concepts and discoveries concepts and discoveries the...

LECTURE 10LECTURE 10

Medicine in the Medicine in the 2020thth

centurycentury

Concepts and discoveriesConcepts and discoveries The development of anatomy The development of anatomy

and its disciplinesand its disciplines The development of physiology The development of physiology

and physiopathologyand physiopathology The development of The development of

microbiology and its microbiology and its disciplinesdisciplines

Medicine in the 20th centuryMedicine in the 20th century

The healing art has changed almost beyond recognition The healing art has changed almost beyond recognition during twentieth century. Most of the extraordinary during twentieth century. Most of the extraordinary innovations, when viewed historically, are chiefly innovations, when viewed historically, are chiefly remarkable extensions of past contributions and remarkable extensions of past contributions and attitudes.attitudes.

The intensive research on inborn or genetic errors The intensive research on inborn or genetic errors started in the 1940s. Soon it became clear that the started in the 1940s. Soon it became clear that the normal human chromosome count is forty-six. Later, normal human chromosome count is forty-six. Later, techniques were developed for prenatally diagnosing techniques were developed for prenatally diagnosing genetic diseases by culturing cells obtained from the genetic diseases by culturing cells obtained from the amniotic fluid. Due to these technological advances, the amniotic fluid. Due to these technological advances, the science of human genetics has now become a speciality science of human genetics has now become a speciality which is capable of proper diagnosis, counselling and which is capable of proper diagnosis, counselling and prevention of many serious diseases.prevention of many serious diseases.

At the end of World War II, immunology entered a phase At the end of World War II, immunology entered a phase which permitted a molecular biological explanation for which permitted a molecular biological explanation for many of the immune phenomena associated with many of the immune phenomena associated with infectious disease. It was also proved that many other infectious disease. It was also proved that many other biological activities, not directly related to infectious biological activities, not directly related to infectious diseases, actually have an immunological basis.diseases, actually have an immunological basis.


The invention of the electron microscope in the late The invention of the electron microscope in the late 1930s made possible the examination of the structure 1930s made possible the examination of the structure of viruses in great detail and the study of their of viruses in great detail and the study of their relationships with the cells they infect. The practical relationships with the cells they infect. The practical results of the advances in virology have had beneficial results of the advances in virology have had beneficial effects on the health of mankind. Vaccines against effects on the health of mankind. Vaccines against poliomyelitis, measles, German measles were poliomyelitis, measles, German measles were developed. Some success has also been achieved in the developed. Some success has also been achieved in the prevention of influenza.prevention of influenza.

Electron microscopy showed that the cell includes a Electron microscopy showed that the cell includes a multitude of smaller components with definite multitude of smaller components with definite functions in maintaining the life and activity of the functions in maintaining the life and activity of the cell itself.cell itself.

The development of psychiatry began in the year 1900, The development of psychiatry began in the year 1900, when Sigmund Freud (1856-1939) published "The when Sigmund Freud (1856-1939) published "The Interpretation of Dreams". He induced a revolution in Interpretation of Dreams". He induced a revolution in the field of psychiatry by creating psychoanalysis. the field of psychiatry by creating psychoanalysis. Among its basic concepts is that human behaviour is Among its basic concepts is that human behaviour is heavily influenced by unconscious mental processes, heavily influenced by unconscious mental processes, that childhood experiences play a crucial role in that childhood experiences play a crucial role in development, and that internal psychological conflict development, and that internal psychological conflict is of central importance in mental life.is of central importance in mental life.


With the discovery of X-rays in 1895 and radium in 1898 With the discovery of X-rays in 1895 and radium in 1898 two potentially dangerous sources of ionizing rays were two potentially dangerous sources of ionizing rays were uncovered. Even in the early years of the twentieth uncovered. Even in the early years of the twentieth century, radium proved useful for the treatment of century, radium proved useful for the treatment of cancer. The X-ray became a powerful tool for the cancer. The X-ray became a powerful tool for the diagnosis of disease and later for the therapy of tumors.diagnosis of disease and later for the therapy of tumors.

A new development from the use of internally deposited A new development from the use of internally deposited radioactive materials arose after World War II. radioactive materials arose after World War II. Radioactive chemicals were injected into the body and Radioactive chemicals were injected into the body and theirs varied distribution determined by a detector of theirs varied distribution determined by a detector of radioactivity has been able to show abnormalities in the radioactivity has been able to show abnormalities in the thyroid, liver, lungs and other organs.thyroid, liver, lungs and other organs.

The achievement of safe blood transfusions in humans The achievement of safe blood transfusions in humans was a major step in the treatment of haemorrhage and was a major step in the treatment of haemorrhage and anaemia and opened the way for surgical procedures anaemia and opened the way for surgical procedures otherwise too dangerous.otherwise too dangerous.

Some of the chemical components of the shell of a red Some of the chemical components of the shell of a red blood cell differ slightly in different people. In 1901, blood cell differ slightly in different people. In 1901, Landsteiner described the major red blood cell types A, Landsteiner described the major red blood cell types A, B, C and later AB.B, C and later AB.


The most important impulse to discovery ways of fighting The most important impulse to discovery ways of fighting oorganisms was given by the works of Paul Ehrlich (1854-oorganisms was given by the works of Paul Ehrlich (1854-1915). i student he examined the methods of making cells 1915). i student he examined the methods of making cells visible under microscope and he wrote his doctoral thesis visible under microscope and he wrote his doctoral thesis on histologic stains. on histologic stains.

In 1928, Alexander Fleming (1881-1955) noticed that In 1928, Alexander Fleming (1881-1955) noticed that bacteria could not grow on a culture-medium accidentally bacteria could not grow on a culture-medium accidentally contaminated with a mould, contaminated with a mould, Penicillium notatum. Penicillium notatum. Evidently Evidently the mould produced something ficmous to bacteria, which the mould produced something ficmous to bacteria, which Fleming called Penicillin.Fleming called Penicillin.

Other types of antibiotics followed in rapid order. The first Other types of antibiotics followed in rapid order. The first to be discovered was streptomycin in 1944 and proved to be to be discovered was streptomycin in 1944 and proved to be useful against a variety of infections, especially useful against a variety of infections, especially tuberculosis.tuberculosis.

As new substances were used, their bacterial targets As new substances were used, their bacterial targets developed resistance, so researchers have had to enter an developed resistance, so researchers have had to enter an ever-quickening race to stay ahead of the adaptation by ever-quickening race to stay ahead of the adaptation by germs to each new drug.germs to each new drug.

In 1913, John J. Abel, L.G. Rowntree and B.B. Turner In 1913, John J. Abel, L.G. Rowntree and B.B. Turner developed a mechanical system, which they called an developed a mechanical system, which they called an "artificial kidney". After cellophane and heparin were "artificial kidney". After cellophane and heparin were discovered, Willem J. Kolff from the Netherlands built an discovered, Willem J. Kolff from the Netherlands built an effective apparatus in 1945 which was used successfully in effective apparatus in 1945 which was used successfully in humans.humans.


When Christiaan Barnard performed the first heart When Christiaan Barnard performed the first heart transplant operation in 1967 in Capetown, the world transplant operation in 1967 in Capetown, the world realized that a new era of surgery had arrived.realized that a new era of surgery had arrived.

The first report in the medical literature of organ The first report in the medical literature of organ transplantation came from Vienna at the begining of transplantation came from Vienna at the begining of the twentieth century when Emerich Ullmann the twentieth century when Emerich Ullmann transplanted a dog's kidney from its normal position transplanted a dog's kidney from its normal position to the neck.to the neck.

In 1954, a medical team from Boston transplanted In 1954, a medical team from Boston transplanted successfully and permanently a kidney from an successfully and permanently a kidney from an identical twin to his brother who was dying of kidney identical twin to his brother who was dying of kidney failure. But the transferring of a kidney in nonrelated failure. But the transferring of a kidney in nonrelated persons was not successful until researchers were persons was not successful until researchers were able to prevent the rejection of transplants through able to prevent the rejection of transplants through drugs that lower the recipient's immunological drugs that lower the recipient's immunological responses.responses.

In 1902, William Bayliss and Ernest Starling in In 1902, William Bayliss and Ernest Starling in London discovered that a chemical substance from London discovered that a chemical substance from intestinal tissue was capable of stimulating secretion intestinal tissue was capable of stimulating secretion from the pancreatic gland. They revolutionized from the pancreatic gland. They revolutionized biologic science by proving that organ function could biologic science by proving that organ function could be regulated by chemical as well as by nerves.be regulated by chemical as well as by nerves.


Perhaps the most famous contribution to endocrinology Perhaps the most famous contribution to endocrinology was the isolation of insulin in 1921. Although Frederick was the isolation of insulin in 1921. Although Frederick Banting and Charles Best have been credited with the Banting and Charles Best have been credited with the discovery of insulin, it was the Romanian Nicolae Paulescu discovery of insulin, it was the Romanian Nicolae Paulescu (1869-1931) who prepared a pancreatic extract which he (1869-1931) who prepared a pancreatic extract which he called "pancrein". A few months before the Americans called "pancrein". A few months before the Americans announced the isolation of insulin, Paulescu obtained a announced the isolation of insulin, Paulescu obtained a dramatic fall of thedramatic fall of the blood glucose level after injecting his blood glucose level after injecting his extract in a dog with sxperimental diabetes. extract in a dog with sxperimental diabetes.

Over subsequent decades, various types of injectable long-Over subsequent decades, various types of injectable long-acting insulins were prepared for the treatment of acting insulins were prepared for the treatment of diabetes.diabetes.

The World Health Organization (WHO) was founded in The World Health Organization (WHO) was founded in 1946. It is an agency of the United Nations dedicated to 1946. It is an agency of the United Nations dedicated to the principle that 'health is a state of complete physical, the principle that 'health is a state of complete physical, mental and social well-being, and not merely the absence mental and social well-being, and not merely the absence of disease or infirmity" which should be the right of all of disease or infirmity" which should be the right of all people. WHO supervises international quarantine rules people. WHO supervises international quarantine rules and the notification of serious epidemics.and the notification of serious epidemics.


The first objective of WHO, to eliminate smallpox, The first objective of WHO, to eliminate smallpox, was achieved in 1980. This must count as one of was achieved in 1980. This must count as one of the greatest triumphs of human endeavour. The the greatest triumphs of human endeavour. The next targets are malaria and leprosy.next targets are malaria and leprosy.

These are only a few from the many achievements These are only a few from the many achievements of the healing art in the twentieth century. Very of the healing art in the twentieth century. Very soon this century's ideas and activities will be soon this century's ideas and activities will be reviewed by the next century's historians and reviewed by the next century's historians and scientists. We would do well to view today's scientists. We would do well to view today's medicine as merely a marker between the past medicine as merely a marker between the past and future.and future.

lecture 10 medicine in the 20 th century. concepts and discoveries concepts and discoveries the...

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