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Dysmenorrhea as a Menstrual Disorder

Dysmenorrhea refers to painful menstrual bleeding and often includes symptoms such as cramps in the lower abdominal region, pain radiating down to the thighs, nausea and vomiting, diarrhea, fatigue, and headaches. There are two types of dysmenorrhea, called primary and secondary dysmenorrhea, which develop in different ways. In cases of primary dysmenorrhea, people experience painful cramps before and during most of their menstrual cycles, which does not happen as a result of a different underlying condition and is mostly due to hormone imbalances.

Format: Articles

Subject: Disorders, Theories

Amenorrhea as a Menstrual Disorder

Amenorrhea is considered a type of abnormal menstrual bleeding characterized by the unexpected absence of menstrual bleeding, lasting three months or longer. Menstrual bleeding typically happens approximately once a month when blood and endometrial tissue, or tissue lining the inside of the uterus, sheds from the uterus through the vagina. Menstruation is expected to stop with pregnancy, breastfeeding, and menopause, or the natural cessation of the menstrual cycle at an older age.

Format: Articles

Subject: Disorders, Reproduction

Ian Donald (1910–1987)

Ian Donald was an obstetrician who developed the technology and therapy of ultrasound diagnostics during the twentieth century in Europe. Ultrasound is a medical diagnostic technique that uses sound waves to produce images of the inside of the body. During the early 1900s, physicians had no way to see inside a woman’s uterus during pregnancy. Donald developed the first method of scanning human internal anatomy in real time, which enabled doctors to diagnose potentially fatal tumors and cysts.

Format: Articles

Subject: People

Leonard Colebrook (1883–1967)

Leonard Colebrook was a physician who researched bacteria and infections in England during the twentieth century. In 1936, Colebrook deployed the antibiotic Prontosil to treat puerperal fever, a disorder that results from bacterial infections in the uterine tracts of women after childbirth or abortions. Colebrook also advanced care for burn patients by advocating for the creation of burn units in hospitals and by using antisepsis medication for burn wound infections. Colebrook’s work on treatments for puerperal fever reduced cases of puerperal fever throughout the world.

Format: Articles

Subject: People

Barbara McClintock's Transposon Experiments in Maize (1931–1951)

Barbara McClintock conducted experiments on corn (Zea mays) in the United States in the mid-twentieth century to study the structure and function of the chromosomes in the cells. McClintock researched how genes combined in corn and proposed mechanisms for how those interactions are regulated. McClintock received the Nobel Prize in Physiology or Medicine in 1983, the first woman to win the prize without sharing it. McClintock won the award for her introduction of the concept of transposons, also called jumping genes.

Format: Articles

Subject: Experiments

Hermann Joseph Muller (1890-1967)

Hermann Joseph Muller studied the effects of x-ray radiation on genetic material in the US during the twentieth century. At that time, scientists had yet to determine the dangers that x-rays presented. In 1927, Muller demonstrated that x-rays, a form of high-energy radiation, can mutate the structure of genetic material. Muller warned others of the dangers of radiation, advising radiologists to protect themselves and their patients from radiation. He also opposed the indiscriminate use of radiation in medical and industrial fields.

Format: Articles

Subject: People

Essay: Review of Icons of Life: A Cultural History of Human Embryos

To Lynn M. Morgan, the Mary E. Woolley Professor of Anthropology at Mt. Holyoke College, nothing says life more than a dead embryo. In her easily readable book, Icons of Life: A Cultural History of Human Embryos, Morgan brings together cultural phenomena, ethics, and embryology to show that even dead embryos and fetuses have their own stories to tell. As an anthropologist, Morgan is interested in many things, including the science of embryology and its history. But she also wants to know how culture influences our views on embryos and the material practices that accompany their study.

Format: Essays and Theses

Subject: Publications

Austin Bradford Hill (1897-1991)

During the twentieth century, Austin Bradford Hill researched diseases and their causes in England and developed the Bradford Hill criteria, which comprise the minimal requirements that must be met for a causal relationship to be established between a factor and a disease. Hill also suggested that researchers should randomize clinical trials to evaluate the effects of a drug or treatment by monitoring large groups of people.

Format: Articles

Subject: People

Percivall Pott (1714-1788)

Percivall Pott was a physician in England during the eighteenth century who identified soot as the cause of chimney sweeps' scrotal cancer, later called testicular cancer. In the 1770s, Pott observed that scrotal cancer commonly afflicted chimney sweeps, the young boys sent up into chimneys to clean away the soot left over from fires, and he hypothesized that the soot inside chimneys might cause that type of cancer. Pott was one of the first doctors to identify some environmental factor as causing cancer.

Format: Articles

Subject: People

Julia Barlow Platt (1857-1935)

Julia Barlow Platt studied neural crests in animal embryos and became involved in politics in the US during the nineteenth and twentieth centuries. She researched how body and head segments formed in chicks (Gallus gallus) and spiny dogfish (Squalus acanthias). Platt observed that in the mudpuppy (Necturus maculosus), the coordinated migration of neural crest cells in the embryo produced parts of the nervous system, bones, and connective tissues in the head.

Format: Articles

Subject: People

Columbia Gang

Format: Photographs

Subject: People

Columbia Gang

Format: Photographs

Subject: People

Countdown to Life: The Extraordinary Making of You (2015), by the British Broadcasting Corporation and The Open University

In 2015, the British Broadcasting Corporation (BBC) partnered with The Open University to produce the three-part documentary series, Countdown to Life: The Extraordinary Making of You. Michael Mosley, a British television producer and journalist, hosts the documentary. Along with narrating animated scenes of a growing fetus in the womb, Mosley meets with individuals around the world who experienced mutations that can arise in the womb. Introduced over the course of the three episodes, several people share their personal stories of how their bodies did not develop correctly prior to birth.

Format: Articles

Subject: Publications

Robert Guthrie (1916–1995)

Robert Guthrie developed a method to test infants for phenylketonuria (PKU) in the United States during the twentieth century. PKU is an inherited condition that causes an amino acid called phenylalanine to build to toxic levels in the blood. Untreated, PKU causes mental disabilities. Before Guthrie’s test, physicians rarely tested infants for PKU and struggled to diagnosis it. Guthrie’s test enabled newborns to be quickly and cheaply screened at birth and then treated for PKU if necessary, preventing irreversible neurological damage.

Format: Articles

Subject: People

William Keith Brooks (1848-1908)

Biologist William Keith Brooks studied embryological development in invertebrates and used his results as evidence for theories of evolution and ancestral heredity. He founded a marine biological laboratory where his and others' embryological studies took place. Later in life, Brooks became head of the Biology Department at Johns Hopkins University where he helped shape the minds of leading embryologists.

Format: Articles

Subject: People

David Baltimore (1938– )

David Baltimore studied viruses and the immune system in the US during the twentieth century. In 1975, Baltimore was awarded the Nobel Prize in Physiology or Medicine for discovering reverse transcriptase, the enzyme used to transfer information from RNA to DNA. The discovery of reverse transcriptase contradicted the central dogma of biology at the time, which stated that the transfer of information was unidirectional from DNA, RNA, to protein.

Format: Articles

Subject: People

Michael R. Harrison (1943– )

Michael R. Harrison worked as a pediatric surgeon in the US throughout the late-twentieth century and performed many fetal surgeries, including one of the first successful surgeries on a fetus in utero, or while it is still in its gestational carrier’s body, also called open fetal surgery. A fetus is an organism developing inside of the uterus that is anywhere from eight weeks old to birth. Harrison hypothesized that open fetal surgery could correct developmental defects that may become fatal to the fetus at birth.

Format: Articles

Subject: People

An Atlas of Fertilization and Karyokinesis of the Ovum (1895), by Edmund Beecher Wilson

Edmund Beecher Wilson in the US published An Atlas of Fertilization and Karyokinesis of the Ovum (hereafter called An Atlas) in 1895. The book presents photographs by photographer Edward Leaming that capture stages of fertilization, the fusion of sperm and egg and early development of sea urchin (Toxopneustes variegatus) ova, or egg cell. Prior to An Atlas, no one photographed of eggcell division in clear detail. Wilson obtained high quality images of egg cells by cutting the cells into thin sections and preserving them throughout different stages of development.

Format: Articles

Subject: Publications, Reproduction

Richard Doll (1912–2005)

Richard Doll was an epidemiologist and public figure in the twentieth and early twenty-first centuries. Working primarily at the University of Oxford, in Oxford, England, Doll established a definitive correlation between cigarette smoking and lung cancer. Furthermore, Doll’s work helped legitimize epidemiology as a scientific discipline. Doll’s research also helped establish modern guidelines for oncological studies, as well as for contemporary and future research on the effect of smoking on pregnancy and fetal development.

Format: Articles

Subject: People

Sidney Q. Cohlan (1915-1999)

Sidney Q. Cohlan studied birth defects in the US during the twentieth century. Cohlan helped to discover that if a pregnant woman ate too much vitamin A her fetus faced a higher than normal risk of teratogenic effects, such as cleft palate. A teratogen is a substance that causes malformation of a developing organism. Cohlan also identified the teratogenic effects of several other substances including a lack of normal magnesium and prenatal exposure to the antibiotic tetracycline.

Format: Articles

Subject: People

Landrum Brewer Shettles (1909-2003)

Landrum Brewer Shettles is remembered as an important contributor to early in vitro fertilization research in the United States as well as a prolific author on the subject of choosing a child's sex before conception. Shettles was born in Pontotoc County, Mississippi on 21 November 1909 to Sue Mounce and Brazil Manly. Shettles trained and worked as a gynecologist at Columbia University Presbyterian Medical Center, after receiving his MD in 1943 from Johns Hopkins University.

Format: Articles

Subject: People, Reproduction

Ignacio Vives Ponseti (1914-2009)

Ignacio Vives Ponseti developed a noninvasive method for treating congenital club foot in the US during the late 1940s. Congenital club foot is a birth deformity in which one or both of an infant's feet are rotated inward beneath the ankle, making normal movement rigid and painful. Ponseti developed a treatment method, later called the Ponseti method, that consisted of a series of manipulations and castings of the club foot performed in the first few months of life.

Format: Articles

Subject: People

The Roslin Institute (1993- )

The Roslin Institute was established in 1993 in the village of Roslin, Scotland, as an independent research center by the Biotechnology and Biological Sciences Research Council (BBSRC), and as of 2014 is part of the University of Edinburgh in Edinburgh, Scotland. Researchers at the Roslin Institute cloned the Dolly the sheep in 1996. According to the Roslin Institute, Dolly was the first mammal to develop into an adult from the transfer of the nucleus of an adult sheep cell into an ovum with the nucleus removed.

Format: Articles

Subject: Organizations