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Displaying 551 - 575 of 934 items.

Elinor Catherine Hamlin (1924- )

Elinor Catherine Hamlin founded and helped fund centers in Ethiopia to treat women affected by fistulas from obstetric complications. Obstetric fistulas develop in women who experience prolonged labor, as the pressure placed on the pelvis by the fetus during labor causes a hole, or fistula, to form between the vagina and the bladder (vesicovaginal fistula) or between the vagina and the rectum (rectovaginal fistula). Both of those conditions result in urinary or fecal incontinence, which often impacts womenÍs social status within their communities.

Format: Articles

Subject: People, Reproduction

"β-Catenin Defines Head Versus Tail Identity During Planarian Regeneration and Homeostasis" (2007), by Kyle A. Gurley, Jochen C. Rink, and Alejandro Sánchez Alvarado

Alejandro Sánchez Alvarado's laboratory group has employed molecular tools to investigate old questions about regeneration and as a result have identified some of the molecular mechanisms determining polarity. Recent work by his group has shown Wnt-β-catenin signaling determines whether a tail or a head will form during regeneration in planarians. This study was motivated by work Thomas Hunt Morgan conducted in the late nineteenth century.

Format: Articles

Subject: Experiments

Hamlin Fistula Ethiopia (1974- )

Hamlin Fistula Ethiopia is a nonprofit organization that began in 1974 as a joint endeavor by Reginald and Catherine Hamlin and the Addis Ababa Fistula Hospital in Addis Ababa, Ethiopia. Hamlin Fistula Ethiopia promotes reproductive health in Ethiopia by raising awareness and implementing treatment and preventive services for women affected by obstetric fistulas. It also aims to restore the lives of women afflicted with obstetric fistulas in Ethiopia and eventually to eradicate the condition.

Format: Articles

Subject: Organizations, Reproduction, Outreach

"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 Human Genome Project (1990-2003)

The Human Genome Project (HGP) was an international scientific effort to sequence the entire human genome, that is, to produce a map of the base pairs of DNA in the human chromosomes, most of which do not vary among individuals. The HGP started in the US in 1990 as a public effort and included scientists and laboratories located in France, Germany, Japan, China, and the United Kingdom.

Format: Articles

Subject: Organizations

Dorothy Andersen (1901–1963)

Dorothy Andersen studied cystic fibrosis in the United States during the early 1900s. In 1935, Andersen discovered lesions in the pancreas of an infant during an autopsy, which led her to classify a condition she named cystic fibrosis of the pancreas. In 1938, Andersen became the first to thoroughly describe symptoms of the medical condition cystic fibrosis.

Format: Articles

Subject: People

The Marine Biological Laboratory Embryology Course

The Marine Biological Laboratory (MBL) in Woods Hole, Massachusetts, began in 1888 to offer opportunities for instruction and research in biological topics. For the first few years, this meant that individual investigators had a small lab space upstairs in the one wooden building on campus where students heard their lectures and did their research in a common area downstairs.

Format: Articles

Subject: Organizations

Estrogen and the Menstrual Cycle in Humans

Estrogen is the primary sex hormone in women and it functions during the reproductive menstrual cycle. Women have three major types of estrogen: estrone, estradiol, and estriol, which bind to and activate receptors within the body. Researchers discovered the three types of estrogen over a period of seven years, contributing to more detailed descriptions of the menstrual cycle. Each type of estrogen molecule contains a slightly different arrangement or number of atoms that in turn causes some of the estrogens to be more active than others.

Format: Articles

Subject: Theories, Reproduction

“A Proposed Structure for the Nucleic Acids” (1953) by Linus Pauling and Robert Brainard Corey

In February 1953, Linus Pauling and Robert Brainard Corey, two scientists working at the California Institute of Technology in Pasadena, California, proposed a structure for deoxyribonucleic acid, or DNA, in their article “A Proposed Structure for the Nucleic Acids,” henceforth “Nucleic Acids.” In the article, Pauling and Corey suggest a model for nucleic acids, including DNA, that consisted of three nucleic acid strands wound together in a triple helix.

Format: Articles

Subject: Publications

Edward Charles Dodds (1899-1973)

Edward Charles Dodds researched the function and effects of natural and artificial hormones on the endocrine system in England during the twentieth century. Though he first worked with hormones such as insulin, Dodds focused on the effects of estrogen in the body and how to replicate those effects with artificial substances. In 1938, along with chemist Robert Robinson, Dodds synthesized the first synthetic estrogen called diethylstilbestrol.

Format: Articles

Subject: People

John Tyler Bonner (1920- )

The establishment and growth of developmental-evolutionary biology owes a great debt to the work of John Tyler Bonner. Bonner's studies of cellular slime molds have shed light on some of the big questions of biology including the origins of multicellularity and the nature of morphogenesis. The second child of Lilly Marguerite Stehli and Paul Bonner, John Tyler was born 12 May 1920 in New York City and spent his early years in Locust Valley, Long Island (late 1920s), France (1930), and London (1932).

Format: Articles

Subject: People

Transposition of the Great Arteries (TGA)

Transposition of the great arteries or TGA is a potentially fatal congenital heart malformation where the pulmonary artery and the aorta are switched. The switch means that the aorta, which normally carries oxygenated blood, carries deoxygenated blood. There are two types of the malformation, d-TGA where no oxygen reaches the body and l-TGA where some oxygenated blood circulates. In the US, the Centers for Disease Control estimate that about 1,901 infants are born each year with TGA, or about one for every 2,000 births.

Format: Articles

Subject: Disorders

The Meselson-Stahl Experiment (1957–1958), by Matthew Meselson and Franklin Stahl

In an experiment later named for them, Matthew Stanley Meselson and Franklin William Stahl in the US demonstrated during the 1950s the semi-conservative replication of DNA, such that each daughter DNA molecule contains one new daughter subunit and one subunit conserved from the parental DNA molecule. The researchers conducted the experiment at California Institute of Technology (Caltech) in Pasadena, California, from October 1957 to January 1958.

Format: Articles

Subject: Processes, Experiments

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

Frank Rattray Lillie's Study of Freemartins (1914-1920)

Frank Rattray Lillie's research on freemartins from 1914 to 1920 in the US led to the theory that hormones partly caused for sex differentiation in mammals. Although sometimes applied to sheep, goats, and pigs, the term freemartin most often refers to a sterile cow that has external female genitalia and internal male gonads and was born with a normal male twin.

Format: Articles

Subject: Experiments

Zygote Intrafallopian Transfer

Zygote intrafallopian transfer (ZIFT) is an assisted reproductive technology (ART) first used in 1986 to help those who are infertile conceive a child. ZIFT is a hybrid technique derived from a combination of in vitro fertilization (IVF) and gamete intrafallopian transfer (GIFT) procedures. Despite a relatively high success rate close to that of IVF, it is not as common as its parent procedures due to its costs and more invasive techniques.

Format: Articles

Subject: Technologies, Reproduction

Edward B. Lewis (1918-2004)

Edward B. Lewis studied embryonic development in Drosophila, including the discovery of the cis-trans test for recessive genes, and the identification of the bithorax complex and its role in development in Drosophila. He shared the 1995 Nobel Prize in Physiology or Medicine with Christiane Nüsslein-Volhard and Eric F. Wieschaus for work on genetic control of early embryonic development.

Format: Articles

Subject: People

Benjamin Harrison Willier (1890-1972)

Benjamin Harrison Willier is considered one of the most versatile embryologists to have ever practiced in the US. His research spanned most of the twentieth century, a time when the field of embryology evolved from being a purely descriptive pursuit to one of experimental research, to that of incorporating molecular biology into the research lab. Willier was born on 2 November 1890 near Weston, Ohio to Mary Alice Ricard. He spent his childhood doing farming chores and running the farm while his father, David Willier worked as a banker.

Format: Articles

Subject: People

Genetics and IVF Institute, GIVF

In 1984, human genetics and reproduction researcher and physician Joseph D. Schulman founded the Genetics and IVF Institute, an international organization that provides infertility treatment and genetic services to patients. IVF stands for in vitro fertilization, an infertility treatment in which a female egg is fertilized by male sperm outside of the female body. GIVF is headquartered in Fairfax, Virginia, in association with Inova Health System, formerly called the Fairfax Hospital Association, one of the largest regional hospital systems in the United States.

Format: Articles

Subject: Organizations, Reproduction

In Vitro Fertilization

In vitro fertilization (IVF) is an assisted reproductive technology (ART) initially introduced by Patrick Steptoe and Robert Edwards in the 1970s to treat female infertility caused by damaged or blocked fallopian tubes. This major breakthrough in embryo research has provided large numbers of women the possibility of becoming pregnant, and subsequent advances have dramatically increased their chances. IVF is a laboratory procedure in which sperm and egg are fertilized outside the body; the term "in vitro" is Latin for "in glass."

Format: Articles

Subject: Technologies, Reproduction

Albert William Liley (1929-1983)

Albert William Liley advanced the science of fetal physiology and the techniques of life-saving in utero blood transfusions for fetuses with Rh incompatibility, also known as hemolytic disease. Due to his advances, fetuses too young to survive premature delivery, and likely to die in utero if their Rh incompabilities were left untreated, were successfully transfused and carried to term. Liley was as passionate as a clinician and researcher as he was about his views on the rights of the unborn.

Format: Articles

Subject: People, Reproduction

Thomas Hunt Morgan (1866-1945)

Although best known for his work with the fruit fly, for which he earned a Nobel Prize and the title "The Father of Genetics," Thomas Hunt Morgan's contributions to biology reach far beyond genetics. His research explored questions in embryology, regeneration, evolution, and heredity, using a variety of approaches.

Format: Articles

Subject: People

Clifford Grobstein (1916-1998)

Clifford Grobstein was a traditional, influential, and highly innovative biologist of the mid-twentieth century, gifted with many character facets and pragmatic talents. His early adulthood passion of linking classical embryology with developmental anatomy and medicine was joined by his later pursuit of combining research ethics and science education with public policy.

Format: Articles

Subject: People

"Experiments on Artificial Parthenogenesis in Annelids (Chaetopterus) and the Nature of the Process of Fertilization" (1901), by Jacques Loeb

Jacques Loeb showed that scientists could achieve artificial parthenogenesis with some types of annelid worm eggs through a series of experiments in 1900. Loeb published the results of his experiments in 1901 as "Experiments on Artificial Parthenogenesis in Annelids (Chaetopterus) and the Nature of the Process of Fertilization," in The American Journal of Physiology. Loeb 's results broadened the range of animals to which artificial parthenogenesis applied beyond sea urchins.

Format: Articles

Subject: Experiments

"A molecular wound response program associated with regeneration initiation in planarians" (2012), by Danielle Wenemoser et al.

In 2012, a team of scientists across the US conducted an experiment to find the mechanism that allowed a group of flatworms, planarians, to regenerate any body part. The group included Danielle Wenemoser, Sylvain Lapan, Alex Wilkinson, George Bell, and Peter Reddien. They aimed to identify genes that are expressed by planarians in response to wounds that initiated a regenerative mechanism. The researchers determined several genes as important for tissue regeneration.

Format: Articles

Subject: Experiments