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"Conservatism in Obstetrics" (1916), by Edwin B. Cragin

In 1916 Edwin B. Cragin in the United States published Conservatism in Obstetrics in which he discussed medical practices and techniques to preserve the vitality of pregnant women and their fetuses. Cragin argued that women who give birth via cesarean section, the surgical act of making an incision through both the abdomen and uterus to remove the fetus from a pregnant woman's womb, must rely on that method for future births. That claim was later coined the Dictum of Cragin.

Format: Articles

Subject: Publications

The Development of Silicone Breast Implants for Use in Breast Augmentation Surgeries in the United States

In the 1960s, two plastic surgeons from the United States, Thomas Dillon Cronin and Frank Judson Gerow, collaborated with the Dow Corning Corporation, which specialized in silicone products, to create the first silicone breast implant. Surgeons used the implant, named the Cronin-Gerow implant, to improve the look of a woman’s breasts, by correcting for asymmetry, augmenting the size, or creating a more uplifted profile.

Format: Articles

Subject: Technologies, Processes

"The Limited In Vitro Lifetime of Human Diploid Cell Strains" (1964), by Leonard Hayflick

Leonard Hayflick in the US during the early 1960s showed that normal populations of embryonic cells divide a finite number of times. He published his results as 'The Limited In Vitro Lifetime of Human Diploid Cell Strains' in 1964. Hayflick performed the experiment with WI-38 fetal lung cells, named after the Wistar Institute, in Philadelphia, Pennsylvania, where Hayflick worked. Frank MacFarlane Burnet, later called the limit in capacity for cellular division the Hayflick Limit in 1974.

Format: Articles

Subject: Experiments

Shinya Yamanaka (1962- )

Shinya Yamanaka gained international prominence after publishing articles detailing the successful generation of induced pluripotent stem (iPS) cells, first in mice, then in humans. Yamanaka induced somatic cells to act like human embryonic stem cells (hESCs), allowing researchers to experiment with non-embryonic stem cells with a similar capacity as hESCs. The research involving iPS cells therefore offered new potential for research and application in medical treatment, without many of the ethical objections that hESC research entailed.

Format: Articles

Subject: People

Diethylstilbestrol (DES) in the US

Diethylstilbestrol (DES) is an artificially created hormone first synthesized in the late 1930s. Doctors widely prescribed DES first to pregnant women to prevent miscarriages, and later as an emergency contraceptive pill and to treat breast cancer. However, in 1971, physicians showed a link between DES and vaginal cancer during puberty in the children of women who had taken DES while pregnant. Consequently, the US Food and Drug Administration (FDA) banned its use during pregnancy.

Format: Articles

Subject: Reproduction, Technologies

Ziegler Wax Embryo Models

Three-dimensional anatomical models have long been essential to the learning of science and lend a sense of "control" to those practicing in the field. As the development of embryology grew in importance during the late 1800s, so did the need for models to show intricate details of embryos.

Format: Articles

Subject: Technologies, Reproduction

The Mustard Operation

The Mustard Operation is a surgical technique to correct a heart condition called the transposition of the great arteries (TGA). TGA is a birth defect in which the placement of the two arteries, the pulmonary artery, which supplies deoxygenated blood to the lungs, and the aorta, which takes oxygenated blood to the body are switched. William Thornton Mustard developed the operation later named for him and in 1963 operated on an infant with TGA, and ameliorated the condition, at the Hospital for Sick Children in Toronto, Canada.

Format: Articles

Subject: Technologies, Disorders

The Y-Chromosome in Animals

The Y-chromosome is one of a pair of chromosomes that determine the genetic sex of individuals in mammals, some insects, and some plants. In the nineteenth and twentieth centuries, the development of new microscopic and molecular techniques, including DNA sequencing, enabled scientists to confirm the hypothesis that chromosomes determine the sex of developing organisms. In an adult organism, the genes on the Y-chromosome help produce the male gamete, the sperm cell. Beginning in the 1980s, many studies of human populations used the Y-chromosome gene sequences to trace paternal lineages.

Format: Articles

Subject: Reproduction, Theories

The Boys from Brazil (1978)

The Boys from Brazil is a science fiction film based on the novel of the same name by Ira Levin about an underground neo-Nazi society in South America trying to clone Adolf Hitler, the dictator of Nazi Germany during World War II, to restore the Nazi movement. The film was directed by Franklin Schaffner and released in 1978 by 20th Century Fox in Los Angeles, California. The Boys from Brazil is a film that was one of the first films to depict cloning, and to discuss the ethical implications of genetic engineering, cloning, and eugenics.

Format: Articles

Subject: Publications

David Michael Rorvik (1944–)

David Michael Rorvik is a science journalist who publicized advancements in the field of reproductive medicine during the late twentieth century. Rorvik wrote magazine articles and books in which he discussed emerging methods and technologies that contributed to the progression of reproductive health, including sex determination, in vitro fertilization, and human cloning. During that time, those topics were controversial and researchers often questioned Rorvik’s work for accuracy.

Format: Articles

Subject: People

Transvaginal Ultrasound-Guided Oocyte Retrieval

Transvaginal ultrasound-guided oocyte retrieval, also known as egg retrieval, is a surgical technique used by medical professionals to extract mature eggs directly from the women’s ovaries under the guidance of ultrasound imaging. In 1982, physicians Suzan Lenz and Jorgen Lauritsen at the University of Copenhagen in Copenhagen, Denmark, proposed the technology to improve the egg collection aspect of in vitro fertilization, or IVF. During IVF, a healthcare practitioner must remove mature eggs from a woman’s ovaries to fertilize them with sperm outside of the body.

Format: Articles

Subject: Technologies, Reproduction

Plan B: Emergency Contraceptive Pill

Plan B is a progestin-only emergency contraceptive pill (ECP) that can be taken within seventy-two hours of unprotected sex in order to prevent an unwanted pregnancy. Plan B was created in response to the United States Food and Drug Administration's (US FDA) 1997 request for new drug applications (NDAs) for a dedicated ECP product, and was approved for sales in the US in 1999. Duramed, a subsidiary of Barr Pharmaceuticals, manufactures Plan B for The Women's Capital Corporation (WCC), which owns the patent for Plan B.

Format: Articles

Subject: Technologies, Reproduction

Vaginal Speculum (after 1800)

A vaginal speculum is a medical device that allows physicians and health providers to better view a woman’s cervix and vagina during pelvic exams. Most specula are made of metal and plastic, and physicians insert a portion of the speculum into the patient’s vagina to separate the vaginal walls. Physicians have used devices to view inside a woman’s vagina for centuries, but physicians did not begin using what is known as a speculum in the twenty-first century until the 1800s.

Format: Articles

Subject: Technologies, Reproduction

The Genetic Control and Cytoplasmic Expression of 'Inducibility' in the synthesis of B-galactosidase" (1959), by Arthur B. Pardee, Francois Jacob, and Jacques Monod

Between 1957 and 1959, Arthur Pardee, Francois Jacob, and Jacques Monod conducted a set of experiments at the Pasteur Institute in Paris, France, that was later called the PaJaMa Experiments, a moniker derived from the researchers' last names. In these experiments, they described how genes of a species of single-celled bacteria, called Escherichia coli (E. coli), controlled the processes by which enzymes were produced in those bacteria.

Format: Articles

Subject: Experiments

Simon Edward Fisher (1970-)

Simon Edward Fisher studied the genes that control speech and language in England and the Netherlands in the late twentieth and early twenty-first centuries. In 2001, Fisher co-discovered the FOXP2 gene with Cecilia Lai, a gene related to language acquisition in humans and vocalization in other mammals. When damaged, the human version of the gene leads to language disorders that disrupt language and speech skills. Fisher's discovery validated the hypothesis that genes influence language, resulting in further investigations of language disorders and their heritability.

Format: Articles

Subject: People

“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

“Levator Trauma is Associated with Pelvic Organ Prolapse” (2008), by Hans P. Dietz and Judy M. Simpson

Hans Peter Dietz and Judy Simpson published, “Levator Trauma is Associated with Pelvic Organ Prolapse,” in the journal BJOG: An International Journal of Obstetrics and Gynecology in 2008. In their article, Dietz and Simpson estimated the risk of pelvic organ prolapse in women who attained injuries to the pelvic levator muscles. The levator muscles, also known as the levator ani, are a major muscle group that comprise the pelvic floor. Along with other muscles, the pelvic floor supports organs in a woman’s pelvis, such as the bladder, uterus, and rectum.

Format: Articles

Subject: Publications, Disorders

“An Extended Family with a Dominantly Inherited Speech Disorder” (1990), by Jane A. Hurst et al.

In 1990, researcher Jane Hurst and her colleagues published “An Extended Family With a Dominantly Inherited Speech Disorder,” in which they proposed that a single gene was responsible for a language disorder across three generations of a family. Affected individuals of the family, called the KE family, had difficulty producing, expressing and comprehending speech. Hurst and her team studied the KE family and the disorder at the Department of Clinical Genetics at the Great Ormond Street Hospital for Children in London, England.

Format: Articles

Subject: Publications, Disorders

The Debate over DNA Replication Before the Meselson-Stahl Experiment (1953–1957)

Between 1953 and 1957, before the Meselson-Stahl experiment verified semi-conservative replication of DNA, scientists debated how DNA replicated. In 1953, James Watson and Francis Crick proposed that DNA was composed of two helical strands that wound together in a coil. Their model suggested a replication mechanism, later termed semi-conservative replication, in which parental DNA strands separated and served as templates for the replication of new daughter strands.

Format: Articles

Subject: Theories

Meselson, Stahl, and the Replication of DNA: A History of "The Most Beautiful Experiment in Biology" (2001), by Frederic Lawrence Holmes

In 2001, Yale University Press published Frederic Lawrence Holmes' book, Meselson, Stahl, and the Replication of DNA: A History of "The Most Beautiful Experiment in Biology" (Replication of DNA), which chronicles the 1950s debate about how DNA replicates. That experiment verified that DNA replicates semi-conservatively as originally proposed by Watson and Crick. Rather than focusing solely on experiments and findings, Holmes's book presents the investigative processes of scientists studying DNA replication.

Format: Articles

Subject: Publications

The Infant Incubator in Europe (1860-1890)

In the nineteenth century, obstetricians in Europe began to construct devices to incubate infants in increasingly controlled environments. The infant incubator is a medical device that maintains stable conditions and a germ free environment for premature infants born before the thirty-seventh week of pregnancy. Records show that physicians had used infant incubators since 1835. However, Jean-Louis-Paul Denuce, a physician who worked in Bordeaux, France, first published about incubator technology in 1857.

Format: Articles

Subject: Technologies, Reproduction

Pregnancy Tests

Throughout history methods involving urine have been a popular way to test for pregnancy. Early ideas ranged from simply observing the color of a woman's urine to the notion that the urine of pregnant women contains special crystals or secretions. Indeed, pregnancy testing can be traced back to 1350 BCE in Ancient Egypt. A written document from the time describes a process in which a woman would urinate on wheat and barley seeds over several days and, depending on which plant grew, both the woman's pregnancy status and the sex of the fetus could be determined.

Format: Articles

Subject: Technologies, Reproduction

“Maternal Stress Responses and Anxiety During Pregnancy: Effects on Fetal Heart Rate” (2000), by Catherine Monk, William Fifer, Michael Myers, Richard Sloan, Leslie Trien, and Alicia Hurtado

In 2000, Catherine Monk, William Fifer, Michael Myers, Richard Sloan, Leslie Trien, and Alicia Hurtado published “Maternal stress responses and anxiety during pregnancy: Effects on fetal heart rate,” in which the authors conducted a study on how pregnant women’s stress and anxiety affects the health of their fetuses. Previous studies had shown that stress and anxiety during pregnancy could cause fetal abnormalities.

Format: Articles

Subject: Publications, Disorders

Evaluation of the Newborn Infant--Second Report (1958), by Virginia Apgar et al.

Virginia Apgar and colleagues wrote “Evaluation of the Newborn Infant—Second Report” in 1958. This article explained that Apgar’s system for evaluating infants’ condition after birth accurately predicted the health of infants. Apgar had developed the scoring system in 1953 to provide a simple method for determining if an infant needed medical attention after birth.

Format: Articles

Subject: Reproduction, Publications