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Displaying 101 - 125 of 423 items.

Theophilus Shickel Painter (1889-1969)

Theophilus Shickel Painter studied the structure and
function of chromosomes in the US during in the early to mid-twentieth century. Painter worked at
the University of Texas at Austin in Austin, Texas. In the 1920s
and 1930s, Painter studied the chromosomes of the salivary gland
giant chromosomes of the fruit fly (Drosophila
melanogaster), with Hermann J. Muller. Muller and Painter
studied the ability of X-rays to cause changes in the chromosomes
of fruit flies. Painter also studied chromosomes in mammals.

Format: Articles

Subject: People

Matthew Howard Kaufman (1942–2013)

Matthew Kaufman was a professor of anatomy at the University of Edinburgh, in Edinburgh, UK, who specialized in mouse anatomy, development, and embryology during the late twentieth century. According to the The Herald, he was the first, alongside his colleague Martin Evans, to isolate and culture embryonic stem cells. Researchers initially called those cells Evans-Kaufman cells. In 1992, Kaufman published The Atlas of Mouse Development, a book that included photographs of mice development and mice organs over time.

Format: Articles

Subject: People

Humanae Vitae (1968), by Pope Paul VI

The "Humanae Vitae," meaning "Of Human Life" and subtitled "On the Regulation of Birth," was an encyclical promulgated in Rome, Italy, on 25 July 1968 by Pope Paul VI. This encyclical defended and reiterated the Roman Catholic Church's stance on family planning and reproductive issues such as abortion, sterilization, and contraception. The document continues to have a controversial reputation today, as its statements regarding birth control strike many Catholics as unreasonable.

Format: Articles

Subject: Religion, Reproduction

“Transfer of a Human Zygote” (1973), by David De Kretzer, Peter Dennis, Bryan Hudson, John Leeton, Alexander Lopata, Ken Outch, James Talbot, and Carl Wood

On 29 September 1973, researchers David De Kretzer, Peter Dennis, Bryan Hudson, John Leeton, Alexander Lopata, Ken Outch, James Talbot, and Carl Wood published “Transfer of a Human Zygote,” in The Lancet. In the article, the authors describe an experiment that resulted in one of the first pregnancies established via in vitro fertilization, or IVF. Prior to the article’s publication in 1973, there was no published evidence demonstrating whether IVF treatment would work in humans, although evidence existed showing that IVF worked in other mammals for breeding purposes.

Format: Articles

Subject: Publications, Processes

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

Ovism

Ovism was one of two models of preformationism, a theory of generation prevalent in the late seventeenth through the end of the eighteenth century. Contrary to the competing theory of epigenesis (gradual emergence of form), preformationism held that the unborn offspring existed fully formed in the eggs or sperm of its parents prior to conception. The ovist model held that the maternal egg was the location of this preformed embryo, while the other preformationism model known as spermism preferred the paternal germ cell, as the name implies.

Format: Articles

Subject: Theories

"The Potency of the First Two Cleavage Cells in Echinoderm Development. Experimental Production of Partial and Double Formations" (1891-1892), by Hans Driesch

Hans Adolf Eduard Driesch was a late-nineteenth and early-twentieth century philosopher and developmental biologist. In the spring of 1891 Driesch performed experiments using two-celled sea urchin embryos, the results of which challenged the then-accepted understanding of embryo development. Driesch showed that the cells of an early embryo, when separated, could each continue to develop into normal larval forms.

Format: Articles

Subject: Experiments, Publications

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

Action of MER-25 and of Clomiphene on the Human Ovary (1963)

Between 1958 and 1962, physicians Olive W. Smith, George V. Smith, and Robert W. Kistner performed experiments that demonstrated the effects of the drugs MER-25 and clomiphene citrate on the female human body. MER-25 and clomiphene citrate are drugs that affect estrogen production in women. At the time of the experiment, researchers did not know which organ or organs the drugs affected, the ovaries and/or the anterior pituitary gland.

Format: Articles

Subject: Experiments

John von Neumann (1903-1957)

John von Neumann was a Hungarian mathematician who made important contributions to mathematics, physics, computer science, and the area of artificial life. He was born in Budapest, Hungary, on 28 December 1903. His mother was Margit von Neumann and his father was Max von Neumann. His work on artificial life focused on the problem of the self-reproduction of machines. Von Neumann initially discussed self-reproducing machines in his Hixon Symposium paper "The General and Logical Theory of Automata" published in 1948.

Format: Articles

Subject: People

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

David Edwin Wildt (1950- )

David Edwin Wildt developed and applied assisted reproductive technologies to conserve rare and endangered wildlife species in the US during the twentieth and twenty-first centuries. He advocated genome resource banks to help preserve biodiversity, and he advocated for practical ethics to guide wildlife reproductive biologists when they use technology and environmental planning. Wildt often focused on the cheetah (Acinonyx jubatus), but he researched greater than fifty vertebrate species.

Format: Articles

Subject: People

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

Pierre Budin (1846-1907)

Pierre Constant Budin worked in France to improve the lives of newborns and their mothers during the late nineteenth century. Budin stressed the importance of proper nutrition in infants and educated new mothers on breastfeeding and infant care. Budin established infant care facilities and created a nutritional check-up system for infants. Budin helped design early artificial nipples, breast pumps, and incubators for premature newborns. He also began the practice of consulting with new mothers after they gave birth, redefining the roles of obstetricians.

Format: Articles

Subject: People, Reproduction

Min Chueh Chang (1908-1991)

As one of the researchers involved in the development of the oral contraceptive pill, Min Chueh Chang helped to revolutionize the birth control movement. Although best known for his involvement with "the pill," Chang also made a number of discoveries throughout his scientific career involving a range of topics within the field of reproductive biology. He published nearly 350 articles in scientific journals.

Format: Articles

Subject: People, Reproduction

John Hunter (1728–1793)

John Hunter studied human reproductive anatomy, and in eighteenth century England, performed one of the earliest described cases of artificial insemination. Hunter dissected thousands of animals and human cadavers to study the structures and functions of organ systems. Much of his anatomical studies focused on the circulatory, digestive, and reproductive systems. He helped to describe the exchange of blood between pregnant women and their fetuses. Hunter also housed various natural collections, as well as thousands of preserved specimens from greater than thirty years of anatomy work.

Format: Articles

Subject: People, Reproduction

George W. Bush Executive Order 13455, June 2007

On 20 January 2001, Republican George W. Bush was sworn in as the forty-third president of the United States, replacing Democrat William J. Clinton. During his eight years in office, Bush issued many executive orders, often altering previous policy. By signing Order 13435 on 22 June 2007, he changed how stem cell research would be performed in America.

Format: Articles

Subject: Legal

No-scalpel Vasectomy

No-scalpel vasectomy, or NSV or keyhole vasectomy, is a surgical method of sterilization that involves puncturing the skin of the scrotum to access the vas deferens, a tube that carries spermatozoa, or sperm, from the testes to the penis. The surgeon performing the procedure blocks the flow of sperm through the vas deferens, sterilizing the patient. NSV is a less invasive procedure, as it does not use a scalpel to make a deep cut on sensitive scrotal tissue.

Format: Articles

Subject: Technologies, People, Organizations, Places, Reproduction

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

“Effect of Air Quality on Assisted Human Reproduction” (2010), by Richard Legro, Mark V. Sauer, Gilbert L. Mottla, Kevin S. Richter, Xian Li, William C. Dodson, and Duanping Liao

In the early 2000s, Richard S. Legro, Mark V. Sauer, Gilbert L. Mottla, Kevin S. Richter, William C. Dodson, and Duanping Liao studied the relationship between air pollution and reproductive complications. In the United States, Legro’s team tracked thousands of women undergoing in vitro fertilization, or IVF, along with the air quality of both the IVF clinics and patients’ home locations.

Format: Articles

Subject: Experiments, Reproduction

Multi-Fetal Pregnancy

In humans, multi-fetal pregnancy occurs when a mother carries more than one fetus during the pregnancy. The most common multi-fetal pregnancy is twins, but mothers have given birth to up to eight children (octuplets) from a single pregnancy. Multiple fetusus can result from the release of multiple eggs or multiple ovulations, the splitting of a single fertilized egg, and fertility treatments such as in vitro fertilization (IVF) which involves the insertion of many fertilized eggs into the mother's uterus.

Format: Articles

Subject: Processes, Reproduction

Jeter v. Mayo (2005)

In Jeter v. Mayo, the Court of Appeals of Arizona in 2005 held that a cryopreserved, three-day-old pre-embryo is not a person for purposes of Arizona's wrongful death statutes, and that the Arizona Legislature was best suited to decide whether to expand the law to include cryopreserved pre-embryos. The Court of Appeals affirmed a decision by the Maricopa County Superior Court to dismiss a couple's wrongful death claim after the Mayo Clinic (Mayo) allegedly lost or destroyed several of their cryopreserved pre-embryos.

Format: Articles

Subject: Reproduction, Legal

Advanced Cell Technology, Inc.

Advanced Cell Technology, Inc. (ACT) is a biotechnology company that uses stem cell technology to develop novel therapies in the field of regenerative medicine. Formed in 1994, ACT grew from a small agricultural cloning research facility located in Worcester, Massachusetts, into a multi-locational corporation involved in using both human embryonic stem cells (hESC) and human adult stem cells as well as animal cells for therapeutic innovations.

Format: Articles

Subject: Organizations, Reproduction

Dickey-Wicker Amendment, 1996

The Dickey-Wicker Amendment is an amendment attached to the appropriations bills for the Departments of Health and Human Services, Labor, and Education each year since 1996 restricting the use of federal funds for creating, destroying, or knowingly injuring human embryos. The Dickey-Wicker Amendment began as a rider (another name for an amendment) attached to House Resolution (H.R.) 2880. H.R.

Format: Articles

Subject: Legal

Gastrulation in Mus musculus (common house mouse)

As mice embryos develop, they undergo a stage of development called gastrulation. The hallmark of vertebrate gastrulation is the reorganization of the inner cell mass (ICM) into the three germ layers: ectoderm, mesoderm, and endoderm. Mammalian embryogenesis occurs within organisms; therefore, gastrulation was originally described in species with easily observable embryos. For example, the African clawed frog (Xenopus laevis) is the most widely used organism to study gastrulation because the large embryos develop inside a translucent membrane.

Format: Articles

Subject: Processes, Experiments