Search

Displaying 651 - 675 of 794 items.

Gamete Intra-Fallopian Transfer (GIFT)

Various techniques constitute assisted reproduction, one of which is gamete intra-fallopian transfer (GIFT). The first example of GIFT involved primates during the 1970s; however, the technology was unsuccessful until 1984 when an effective GIFT method was invented by Ricardo Asch at the University of Texas Health Sciences Center and the procedure resulted in the first human pregnancy. The GIFT technique was created in hopes of generating an artificial insemination process that mimicked the physiological sequences of normal conception.

Format: Articles

Subject: Technologies, Reproduction

Sergio Cereceda Stone (1942- )

Sergio Cereceda Stone was born 16 April 1942 in the coastal city of Valparaiso, Chile. Stone's mother Luz was a housewife and caretaker for Sergio and his younger brother Lionel; his father Sergio served among the country's twenty appellate court judges. In the early 1950s Stone's father relocated the family to Santiago to further his law career.

Format: Articles

Subject: People, Ethics, Reproduction

Facial Abnormalities of Fetal Alcohol Syndrome (FAS)

Prenatal exposure to alcohol (ethanol) results in a continuum of physical, neurological, behavioral, and learning defects collectively grouped under the heading Fetal Alcohol Spectrum Disorder (FASD). Fetal Alcohol Syndrome (FAS) was first defined in 1973 as a condition characterized by pre- and postnatal growth deficiencies, facial abnormalities, and defects of the central nervous system. The pattern of facial defects that occur as a result of ethanol exposure during development primarily affects the midline of the face, altering morphology of the eyes, nose, and lips.

Format: Articles

Subject: Disorders, Reproduction

The Gradient Theory

The gradient theory is recognized as Charles Manning Child's most significant scientific contribution. Gradients brought together Child's interest in development and his fascination with the origins of individuality and organization. The gradient theory grew from his studies of regeneration, which were largely based on work he conducted with marine invertebrates, such as the ascidian flat worm, planaria and the hydroid, tubularia.

Format: Articles

Subject: Theories

"Versuche zur Analyse der Induktionsmittel in der Embryonalentwicklung" (1932), by Hermann Bautzmann, Johannes Holtfreter, Otto Mangold, and Hans Spemann

In "Versuche zur Analyse der Induktionsmittel in der Embryonalentwicklung," published in Naturwissenschaften in 1932, Hermann Bautzmann, Johannes Holtfreter, Otto Mangold, and Hans Spemann jointly reported on experiments each had conducted testing the activity of organizers killed by boiling, freezing, alcohol, and drying. Each of the authors had been independently conducting similar experiments, when Holtfreter made a breakthrough allowing him to produce many more successful transplantations.

Format: Articles

Subject: Experiments

"Genetic Control of Biochemical Reactions in Neurospora" (1941), by George W. Beadle and Edward L. Tatum

George Wells Beadle and Edward Lawrie Tatum's 1941 article Genetic Control of Biochemical Reactions in Neurospora detailed their experiments on how genes regulated chemical reactions, and how the chemical reactions in turn affected development in the organism. Beadle and Tatum experimented on Neurospora, a type of bread mold, and they concluded that mutations to genes affected the enzymes of organisms, a result that biologists later generalized to proteins, not just enzymes.

Format: Articles

Subject: Experiments

Kurt Benirschke (1924-)

Kurt Benirschke studied cells, placentas, and endangered species in Germany and the US during the twentieth century. Benirschke was professor at the University of California in San Diego, California, and a director of the research department at the San Diego Zoo in San Diego, California. He also helped form the research department of the San Diego Zoo and its sister organization, the Center for Reproduction of Endangered Species.

Format: Articles

Subject: People

ABO Blood Type Identification and Forensic Science (1900-1960)

The use of blood in forensic analysis is a method for identifying individuals suspected of committing some kinds of crimes. Paul Uhlenhuth and Karl Landsteiner, two scientists working separately in Germany in the early twentieth century, showed that there are differences in blood between individuals. Uhlenhuth developed a technique to identify the existence of antibodies, and Landsteiner and his students showed that humans had distinctly different blood types called A, B, AB, and O.

Format: Articles

Subject: Theories, Legal, Technologies

Camillo Golgi (1843–1926)

Camillo Golgi studied the central nervous system during the late nineteenth and early twentieth centuries in Italy, and he developed a staining technique to visualize brain cells. Called the black reaction, Golgi’s staining technique enabled him to see the cellular structure of brain cells, called neurons, with much greater precision. Golgi also used the black reaction to identify structures within animal cells like the internal reticular apparatus that stores, packs, and modifies proteins, later named the Golgi apparatus in his honor.

Format: Articles

Subject: People

Hans Spemann (1869-1941)

Hans Spemann was an experimental embryologist best known for his transplantation studies and as the originator of the "organizer" concept. One of his earliest experiments involved constricting the blastomeres of a fertilized salamander egg with a noose of fine baby hair, resulting in a partially double embryo with two heads and one tail.

Format: Articles

Subject: People

The Cell in Development and Inheritance (1900), by Edmund Beecher Wilson

The Cell in Development and Inheritance, by Edmund Beecher Wilson, provided a textbook introduction to cell biology for generations of biologists in the twentieth century. In his book, Wilson integrated information about development, inheritance, chromosomes, organelles, and the structure and functions of cells. First published in 1896, the book started with 371 pages, grew to 483 pages in the second edition that appeared in 1900, and expanded to 1,231 pages by the third and final edition in 1925.

Format: Articles

Subject: Publications

Oviraptor philoceratops Dinosaurs

Oviraptor philoceratops was a small bird-like dinosaur that lived about seventy-five million years ago, during the late Cretaceous period. In 1923, George Olsen of the American Museum of Natural History (AMNH) in New York City, New York, discovered the first Oviraptor fossilized skeleton on top of a dinosaur egg nest in the Gobi Desert, Mongolia. Because of the close proximity of dinosaur and nest, when Henry Fairfield Osborn president of the AMNH published on the discovery, he assumed that the Oviraptor had died attempting to steal the eggs.

Format: Articles

Subject: Organisms

Thomas Raphael Verny (1936– )

During the twentieth century, Thomas Raphael Verny studied the way that environment affects a developing fetus’s character and psychological development. Verny studied the concept of memory before birth and covered both the prenatal and perinatal periods, meaning the time the fetus is in the womb and the weeks immediately before or after birth, respectively. During those times, Verny claimed that patterns of maternal attitudes and experiences, such as affection and stress-related emotions, impact the development of the child.

Format: Articles

Subject: People

Edwin Carlyle (Carl) Wood (1929–2011)

Edwin Carlyle Wood, also known as Carl Wood, was a physician who helped develop in vitro fertilization, or IVF, treatments. From 1964 to 1992, Wood worked as a professor of obstetrics and gynecology at Monash University in Melbourne, Australia, where he was one of the first in the world to lead a team of physicians to establish IVF as a proven treatment for infertility. IVF refers to a medical procedure in which scientists inseminate an egg cell with a sperm cell outside of the body, such as in a glass dish in a clinical setting.

Format: Articles

Subject: People, Technologies, Reproduction

Royal College of Obstetricians and Gynaecologists (1929–1970)

Starting in 1929, the Royal College of Obstetricians and Gynaecologists was a professional association of physicians in the UK that aimed to improve the care of women in childbirth through training and education and to establish obstetrics and gynecology as a medical specialty. The Royal College of Obstetricians and Gynaecologists has contributed to women’s reproductive health by fostering research, establishing standards for physicians specializing in obstetrics and gynecology, and influencing legislation.

Format: Articles

Subject: Organizations

August Karl Gustav Bier (1861–1949)

In the late nineteenth century, August Karl Gustav Bier was a surgeon in Germany who studied spinal cord anesthesia, later called spinal block. Bier found that, depending upon the amount of anesthesia introduced into the spinal cord, a large area of the human body could be numbed to various degrees. Bier established a procedure to numb individuals from the lower legs to the upper abdomen, with the individual’s numbness ranging from them feeling pressure on their body to them feeling nothing at all.

Format: Articles

Subject: People

Using Digital PCR to Detect Fetal Chromosomal Aneuploidy in Maternal Blood (2007)

In 2007, Dennis Lo and his colleagues used digital polymerase chain reaction or PCR to detect trisomy 21 in maternal blood, validating the method as a means to detect fetal chromosomal aneuploidies, or an abnormal number of chromosomes in a cell. The team conducted their research at the Chinese University of Hong Kong in Hong Kong, Hong Kong, and at the Boston University in Boston, Massachusetts.

Format: Articles

Subject: Experiments

Twilight Sleep

Twilight Sleep (Dammerschlaf) was a form
of childbirth first used in the early twentieth century in Germany in
which drugs caused women in labor to enter a state of sleep prior to
giving birth and awake from childbirth with no recollection of the
procedure. Prior to the early twentieth century, childbirth was
performed at home and women did not have anesthetics to alleviate the
pain of childbirth. In 1906, obstetricians Bernhardt Kronig and Karl
Gauss developed the twilight sleep method in 1906 to relieve the pain of

Format: Articles

Subject: Theories

“Studies on the Chemical Nature of the Substance Inducing Transformation of Pneumococcal Types: Induction of Transformation by a Desoxyribonucleic Acid Fraction Isolated from Pneumococcus Type III” (1944) by Oswald Avery, Colin MacLeod and Maclyn McCarty

In 1944, Oswald Avery, Colin MacLeod, and Maclyn McCarty published an article in which they concluded that genes, or molecules that dictate how organisms develop, are made of deoxyribonucleic acid, or DNA. The article is titled “Studies on the Chemical Nature of the Substance Inducing Transformation of Pneumococcal Types: Induction of Transformation by a Desoxyribonucleic Acid Fraction Isolated from Pneumococcus Type III,” hereafter “Transformation.” The authors isolated, purified, and characterized genes within bacteria and found evidence that those genes were made of DNA and not protein.

Format: Articles

Subject: Publications

“The Standardization of Terminology of Female Pelvic Organ Prolapse and Pelvic Floor Dysfunction” (1996), Richard C. Bump, Anders Mattiasson, Kari Bø, Linda P. Brubaker, John O.L. DeLancey, Peter Klarskov, Bob L. Shull, Anthony R.B. Smith

In 1996, a team of researchers associated with the International Continence Society published “The Standardization of Terminology of Female Pelvic Organ Prolapse and Pelvic Floor Dysfunction” in American Journal of Obstetrics and Gynecology. Pelvic organ prolapse is characterized by the descent of the pelvic organs into the lower portion of the pelvis and is often caused by a weakening of the muscles and ligaments that normally hold the organs in place.

Format: Articles

Subject: Publications, Disorders

Berthold Karl Hölldobler (1936– )

Berthold Karl Hölldobler studied social insects like ants in Europe and the US during the twentieth and early twenty-first century. He focused on the social behavior of ants, the evolutionary origins of social insects, and the way ants use chemicals to communicate with each other. Hölldobler’s research reached popular audiences through his co-authored Pulitzer Prize winning book The Ants and through an award winning nature documentary called Ameisen: Die heimliche Weltmacht (Ants: Nature’s Secret Power).

Format: Articles

Ina May Gaskin (1940– )

Ina May Gaskin is a certified professional midwife, or CPM, in the US during the late twentieth and early twenty-first centuries. She worked at the Farm Midwifery Center in Summertown, Tennessee, a center well known for its low rates of intervention, which contributed to low rates of maternal and fetal mortality. One technique Gaskin used when assisting women with delivery helped resolve a complication called shoulder dystocia, which is when a part of the infant’s body is delivered, but the rest of the body is stuck in the birth canal.

Format: Articles

Subject: People

Bowen v. Kendrick (1988)

On 29 June 1988, in Bowen v. Kendrick, the US Supreme Court ruled in a five-to-four decision that the 1981 Adolescent Family Life Act, or AFLA, was constitutional. Under AFLA, the US government could distribute federal funding for abstinence-only sexual education programs, oftentimes given to groups with religious affiliations. As a federal taxpayer, Chan Kendrick challenged the constitutionality of AFLA, claiming it violated the separation of church and state.

Format: Articles

Subject: Legal, Ethics, Outreach

John Langdon Down (1828–1896)

John Langdon Down studied medicine in England in the nineteenth century and was one of the first people to develop a complete description of the disorder that would later be known as Trisomy 21, or Down Syndrome. Down Syndrome is a condition caused by the presence of an extra chromosome, which may cause a person to be born with certain impaired learning abilities and physical features such as a short neck, flattened face, and almond-shaped eyes.

Format: Articles

Subject: People

“Traditional postpartum practices and rituals: a qualitative systematic review” (2007), by Cindy-Lee Dennis, Kenneth Fung, Sophie Grigoriadis, Gail Erlick Robinson, Sarah Romans and Lori Ross

In the 2007 paper “Traditional postpartum practices and rituals: a qualitative systematic review,” Toronto-based researchers showed that women from different cultures around the world follow similar postpartum practices after giving birth. At the University of Toronto in Toronto, Canada, Cindy-Lee Dennis, Kenneth Fung, Sophie Grigoriadis, Gail Erlick Robinson, Sarah Romans, and Lori Ross examined fifty-one studies from over twenty countries that focused on traditional postpartum practices.

Format: Articles

Subject: Publications