Articles

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"The Role of Maternal Mitochondria during Oogenesis, Fertilization and Embryogenesis" (2002), by James M. Cummins Dorothy R. Haskett James M Cummins published 'The Role of Maternal Mitochondria during Oogenesis, Fertilization and Embryogenesis' 30 January 2002 in Reproductive BioMedicine Online. In the article, Cummins examines the role of the energy producing cytoplasmic particles, or organelles called mitochondria. Humans inherit mitochondria from their mothers, and mechanisms have evolved to eliminate sperm mitochondria in early embryonic development. Mitochondria contain their own DNA (mtDNA) separate from nuclear DNA (nDNA). 2014-09-19 4 Jul 2018 - 4:40:59am
"The Spandrels of San Marco and the Panglossian Paradigm: A Critique of the Adaptationist Programme" (1979), by Stephen J. Gould and Richard C. Lewontin M. Elizabeth Barnes The Spandrels of San Marco and the Panglossian Paradigm: A Critique of the Adaptationist Programme, hereafter called The Spandrels, is an article written by Stephen J. Gould and Richard C. Lewontin published in the Proceedings of the Royal Society of London in 1979. The paper emphasizes issues with what the two authors call adaptationism or the adaptationist programme as a framework to explain how species and traits evolved. The paper is one in a series of works in which Gould emphasized the 2014-11-14 4 Jul 2018 - 4:40:59am
"Transfer of Fetal Cells with Multilineage Potential to Maternal Tissue" (2004), by Kiarash Khosrotehrani et al. Alexis Abboud In 2004, a team of researchers at Tufts-New England Medical Center in Boston, Massachusetts, investigated the fetal cells that remained in the maternal blood stream after pregnancy. The results were published in Transfer of Fetal Cells with Multilineage Potential to Maternal Tissue. The team working on that research included Kiarash Khosrotehrani, Kirby L. Johnson, Dong Hyun Cha, Robert N. Salomon, and Diana W. Bianchi. The researchers reported that the fetal cells passed to a pregnant woman during 2014-11-14 4 Jul 2018 - 4:40:59am
"Transplantation of Living Nuclei from Blastula Cells into Enucleated Frogs' Eggs" (1952), by Robert Briggs and Thomas J. King Nicole Newkirk In 1952 Robert Briggs and Thomas J. King published their article, "Transplantation of Living Nuclei from Blastula Cells into Enucleated Frogs' Eggs," in the Proceedings of the National Academy of Sciences, the culmination of a series of experiments conducted at the Institute for Cancer Research and Lankenau Hospital Research Institute in Philadelphia, Pennsylvania. In this paper Briggs and King examined whether nuclei of embryonic cells are differentiated, and by doing so, were the first to conduct a successful nuclear transplantation with amphibian embryos. 2007-11-13 4 Jul 2018 - 4:40:59am
"Versuche zur Analyse der Induktionsmittel in der Embryonalentwicklung" (1932), by Hermann Bautzmann, Johannes Holtfreter, Otto Mangold, and Hans Spemann Adam R. Navis 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. 2007-11-13 4 Jul 2018 - 4:40:59am
"Veterans and Agent Orange Update 1996: Summary and Research Highlights" by the US National Academy of Sciences' Institute of Medicine Cecilia Chou In March 1996, the National Academy of Sciences of the United States released 'Veterans and Agent Orange Update 1996: Summary and Research Highlights,' which summarized research on the health effects of Agent Orange and other herbicides used in the Vietnam War. In their 1996 report, the National Academy connects Agent Orange exposure with two health conditions: spina bifida, a birth defect that occurs when the spinal cord develops improperly, and peripheral neuropathy, a nervous system condition in which the peripheral nerves are damaged. 2017-03-28 4 Jul 2018 - 4:40:59am
"Viable Offspring Derived from Fetal and Adult Mammalian Cells" (1997), by Ian Wilmut et al. Zane Bartlett In the 1990s, Ian Wilmut, Jim McWhir, and Keith Campbell performed experiments while working at the Roslin Institute in Roslin, Scotland. Wilmut, McWhir, and Campbell collaborated with Angelica Schnieke and Alex J. Kind at PPL Therapeutics in Roslin, a company researching cloning and genetic manipulation for livestock. Their experiments resulted in several sheep being born in July 1996, one of which was a sheep named Dolly born 5 July 1996. 2014-10-10 4 Jul 2018 - 4:40:59am
"Vietnam Veterans' Risks for Fathering Babies with Birth Defects" (1984), by J. David Erickson et al. Cecilia Chou In 1984, J. David Erickson and his research team published the results of a study titled 'Vietnam Veterans' Risks for Fathering Babies with Birth Defects' that indicated that Vietnam veterans were at increased risk of fathering infants with serious congenital malformations, or birth defects. 2017-03-28 4 Jul 2018 - 4:40:59am
"Visualizing Human Embryos" (1999), by Bradley Richard Smith Sarah Ly In March 1999 Bradley Richard Smith, a professor at the University of Michigan, unveiled the first digital magnetic resonance images of human embryos. In his article "Visualizing Human Embryos for Scientific American," Smith displayed three-dimensional images of embryos using combinations of Magnetic Resonance Microscopy (MRM), light microscopy, and various computer editing. He created virtual embryo models that it is possible to view as dissections, animations, or in their whole 3D form. Smith's images constitute a new way of visualizing embryos. 2011-03-27 4 Jul 2018 - 4:40:59am
"β-Catenin Defines Head Versus Tail Identity During Planarian Regeneration and Homeostasis" (2007), by Kyle A. Gurley, Jochen C. Rink, and Alejandro Sánchez Alvarado Mary E. Sunderland 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. 2010-03-15 4 Jul 2018 - 4:40:59am
1901 Arizona Comstock Law Lakshmeeramya Malladi In 1901, the Arizona Territorial Legislature codified territorial law that illegalized advertising, causing, or performing abortions anywhere in Arizona. The 1901 code, in conjunction with the federal Comstock Act, regulated the advertisement and accessibility of abortion services and contraceptives in Arizona. The Federal Comstock Act of 1873 had illegalized the distribution of material on contraceptives and abortions through the US Postal Services by labeling contraceptive and abortive material as obscene. 2017-06-28 15 Jan 2019 - 2:12:16am
2D Obstetric Ultrasound Sean Cohmer The development of the obstetric ultrasound has allowed physicians and embryologists to obtain a clear picture of the developing human embryo and fetus during pregnancy. Obstetric ultrasonography, often referred to as ultrasound, is a technology that uses sound waves to produce images of structures inside the human body. A handheld probe emits sound waves, which are reflected back by the different structures within the body. 2012-01-01 4 Jul 2018 - 4:40:59am
40 Weeks (2014) Jessica Pollesche In 2014, Big Belli, a media and social networking brand, released a documentary called 40 Weeks online. The documentary, directed by Christopher Henze, followed multiple women during their pregnancies. The film predominantly features three women, though it includes the stories of many. Throughout the film, women detail their accounts of the physical and emotional changes that occur during pregnancy. 2019-01-30 31 Jan 2019 - 3:41:27am
45 CFR 46: Protection of Human Subjects under United States Law (1974) Megan Kearl In the United States, the Code of Federal Regulations Title 45: Public Welfare, part 46 (45 CFR 46) provides protection for human subjects in research carried out or supported by most federal departments and agencies. 45 CFR 46 created a common federal policy for the protection of such human subjects that was accepted by the Office of Science and Technology Policy and issued by each of the departments and agencies listed in the document. 2010-06-17 4 Jul 2018 - 4:40:59am
A Child Is Born (1965), by Lennart Nilsson Mark Zhang Dell Publishing in New York City, New York, published Lennart Nilsson's A Child Is Born in 1966. The book was a translation of the Swedish version called Ett barn blir till, published in 1965. It sold over a million copies in its first edition, and has translations in twelve languages. Nilsson, a photojournalist, documented a nine-month human pregnancy using pictures and accompanying text written by doctors Axel Ingelman-Sundberg, Claes Wirsen and translated by Britt and Claes Wirsen and Annabelle MacMillian. 2013-09-17 4 Jul 2018 - 4:40:59am
A History of Embryology (1959), by Joseph Needham Karen Wellner In 1931 embryologist and historian Joseph Needham published a well-received three-volume treatise titled Chemical Embryology. The first four chapters from this work were delivered as lectures on Speculation, Observation, and Experiment, as Illustrated by the History of Embryology at the University of London. The same lectures were later released as a book published in 1934 titled A History of Embryology. 2010-06-28 4 Jul 2018 - 4:40:59am
A plant genetically modified that accumulates Pb is especially promising for phytoremediation (2003), by Carmina Gisbert et al. Ernest Nkansah-Dwamena In 2003, Carmina Gisbert and her research team produced a tobacco plant that could remove lead from soil. To do so, they inserted a gene from wheat plants that produces phytochelatin synthase into a shrub tobacco plant (Nicotiana glauca) to increase N. glauca's absorption and tolerance of toxic metals, particularly lead and cadmium. Gisbert and her team aimed to genetically modify a plant so that it could be used for phytoremediation- using plants to remove toxic substances from the soil. 2014-12-30 4 Jul 2018 - 4:40:59am
A Treatise on the Theory and Practice of Midwifery (1752-1764), by William Smellie Yvette Tran A Treatise on the Theory and Practice of Midwifery is a three volume collection of patient accounts that William Smellie published from 1752 to 1764. Smellie, a physician and instructor in obstetrics in Great Britain, published these compilations to share his expertise in reproductive medicine, while also providing his students and colleagues with a source of reference in their own medical practices. Smellie wrote these books to shift obstetrics from a discipline practiced by midwives with limited medical training to one practiced in a medical context by physicians. 2017-05-04 4 Jul 2018 - 4:40:59am
A Treatise on the Theory and Practice of Midwifery, (1752-1764) by William Smellie Yvette Tran A Treatise on the Theory and Practice of Midwifery is a three volume collection of patient accounts that William Smellie published from 1752 to 1764. Smellie, a physician and instructor in obstetrics in Great Britain, published these compilations to share his expertise in reproductive medicine, while also providing his students and colleagues with a source of reference in their own medical practices. Smellie wrote these books to shift obstetrics from a discipline practiced by midwives with limited medical training to one practiced in a medical context by physicians. 2017-07-23 4 Jul 2018 - 4:40:59am
A. Z. v. B. Z. (2000) Jennifer E. Chapman In A.Z. v. B.Z. (2000), the Supreme Judicial Court of Massachusetts in Boston, Massachusetts, affirmed a lower courtÕs decision, ruling that contracts that require a party to become a parent against his or her will are unenforceable and contrary to public policy. The case centered around A.Z. and B.Z., a divorced couple who had previously used in vitro fertilization (IVF) to start a family together during their marriage and had several preembryos cryopreserved as part of the process. 2013-11-01 4 Jul 2018 - 4:40:59am
A.Z. v. B.Z. [Brief] (2000) Brock Heathcotte The Massachusetts Supreme Court in a case of first impression decided that a prior written agreement between a husband and wife regarding the disposition of frozen embryos in the event of a divorce was unenforceable. This was the first case to reject the presumption that written agreements to conduct in vitro fertilization practices were binding. The court would not force the husband to become a parent merely because he signed a consent form that would have awarded the frozen embryos to his wife in the event of marital separation. 2008-05-09 4 Jul 2018 - 4:40:59am
ABO Blood Type Identification and Forensic Science (1900-1960) Corey Harbison 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. 2016-06-02 4 Jul 2018 - 4:40:58am
Abortion Christina Raup Abortion is the removal of the embryo or fetus from the womb, before birth can occur-either naturally or by induced labor. Prenatal development occurs in three stages: the zygote, or fertilized egg; the embryo, from post-conception to eight weeks; and the fetus, from eight weeks after conception until the baby is born. After abortion, the infant does not and cannot live. Spontaneous abortion is the loss of the infant naturally or accidentally, without the will of the mother. It is more commonly referred to as miscarriage. 2010-06-10 4 Jul 2018 - 4:40:59am
Abraham Trembley (1710-1784) Mary E. Sunderland Abraham Trembley's discovery of the remarkable regenerative capacity of the hydra caused many to question their beliefs about the generation of organisms. Born 3 September 1710 to a prominent Geneva family, Trembley studied at the Calvin Institute, now the University of Geneva, where he completed his thesis on calculus. He went on to become tutor for Count William Bentinck's two sons, and it was while teaching the boys natural history that Trembley came across a strange organism in a sample of pond water. 2007-10-31 4 Jul 2018 - 4:40:59am
Acid Dissolution of Fossil Dinosaur Eggs Paige Madison Acid dissolution is a technique of removing a fossil from the surrounding rock matrix in which it is encased by dissolving that matrix with acid. Fossilized bone, though strong enough to be preserved for thousands or millions of years, is often more delicate than rock. Once a fossil is discovered, scientists must remove the fossil from its surroundings without damaging the fossil itself. 2017-02-11 4 Jul 2018 - 4:40:59am
Action of MER-25 and of Clomiphene on the Human Ovary (1963) Alexis Darby, Alexis J. Abboud 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. 2017-11-28 4 Jul 2018 - 4:40:59am
Adib Jatene (1929–2014) Daniella Caudle Adib Jatene in Brazil was the first surgeon to successfully perform the arterial switch operation in 1975. The operation corrected a heart condition in infants called transposition of the great arteries (TGA). Left untreated, infants with TGA die, as their blood cannot supply oxygen to their bodies. Jatene’s operation became widely used to correct the condition. Aside from medical research, Jatene worked for years in politics and education, serving as Brazil’s minister of health and teaching thoracic surgery at the University of São Paulo. 2017-04-20 4 Jul 2018 - 4:40:59am
Adolf Ziegler Karen Wellner The scientific field of embryology experienced great growth in scope and direction in Germany from approximately 1850 to 1920. During this time, Adolf Ziegler and his son Friedrich crafted hundreds of wax embryo models, representing a shift in how embryos were viewed and used. Their final products, whether human or trout embryos, showcased the now lost collaboration between wax modeling artists and embryologists. 2009-06-10 4 Jul 2018 - 4:40:59am
Advanced Cell Technology, Inc. Lijing Jiang 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. 2010-06-25 4 Jul 2018 - 4:40:59am
Agent Orange as a Cause of Spina Bifida Cecilia Chou Spina bifida is a birth defect that affects the spines of developing fetuses and infants, and research in the 20th century indicated that chemicals in the herbicide Agent Orange likely lead to the birth defect. People with spina bifida can have nerve damage, paralysis, and mental disabilities. During the Vietnam War in the 1960s, the US military employed Agent Orange and other herbicides to destroy enemy crops and forest cover until 1970. 2017-03-09 4 Jul 2018 - 4:40:59am
Agent Orange Birth Defects Jesse King, Cecilia Chou Sprayed extensively by the US military in Vietnam, Agent Orange contained a dioxin contaminant later found to be toxic to humans. Despite reports by Vietnamese citizens and Vietnam War veterans of increased rates of stillbirths and birth defects in their children, studies in the 1980s showed conflicting evidence for an association between the two. In 1996, the US National Academy of Sciences reported that there was evidence that suggested dioxin and Agent Orange exposure caused spina bifida, a birth defect in which the spinal cord develops improperly. 2017-03-07 4 Jul 2018 - 4:40:59am
Alan Mathison Turing (1912-1954) Julia Damerow Alan Mathison Turing was a British mathematician and computer scientist who lived in the early twentieth century. Among important contributions in the field of mathematics, computer science, and philosophy, he developed a mathematical model of morphogenesis. This model describing biological growth became fundamental for research on the process of embryo development. 2010-06-22 4 Jul 2018 - 4:40:59am
Albert William Liley (1929-1983) Kathleen O'Connor 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. 2011-05-11 4 Jul 2018 - 4:40:59am
Albrecht von Haller (1708-1777) Cera R. Lawrence Victor Albrecht von Haller was an 18th century scientist who did extensive work in the life sciences, including anatomy and physiology, botany, and developmental biology. His embryological work consisted of experiments in understanding the process of generation, and led him to adopt the model of preformationism called ovism (the idea that the new individual exists within the maternal egg prior to conception). Haller was born in Bern, Switzerland, on 16 October, 1708. His mother was Anna Maria Engel, and his father was Niklaus Emanuel Haller. 2008-09-22 4 Jul 2018 - 4:40:59am
Alec Jeffreys’s Experiments to Identify Individuals by Their Beta-globin Genes (1977-1979) Corey Harbison In a series of experiments in the late 1970s, Alec J. Jeffreys in the UK and Richard A. Flavell in the Netherlands developed a technique to detect variations in the DNA of different individuals. They compared fragments of DNA from individuals’ beta-globin genes, which produce a protein in hemoglobin. Previously, to identify biological material, scientists focused on proteins rather than on genes. But evidence about proteins enabled scientists only to exclude, but not to identify, individuals as the sources of the biological samples. 2017-07-20 18 May 2019 - 3:29:49am
Alec John Jeffreys (1950–) Corey Harbison Alec John Jeffreys created a process called DNA fingerprinting in the UK during the twentieth century. For DNA fingerprinting, technicians identify a person as the source of a biological sample by comparing the genetic information contained in the person's DNA to the DNA contained in the sample. Jeffreys developed the technique in the 1980s while at the University of Leicester in Leicester, UK. Jeffreys's technique had immediate applications. In forensic science, DNA fingerprinting enabled police to identify suspects of crimes based on their genetic identities. 2017-06-15 4 Jul 2018 - 4:40:59am
Alejandro Sánchez Alvarado (1964- ) Mary E. Sunderland Alejandro Sánchez Alvarado is a Professor of Neurobiology and Anatomy at the University of Utah School of Medicine and is also a Howard Hughes Medical Institute Investigator. Born in Caracas, Venezuela, 24 February 1964, Sánchez Alvarado left his home to pursue education in the United States, where he received a Bachelor of Science in molecular biology and chemistry from Vanderbilt University in 1986 and a Doctorate in pharmacology and cell biophysics at the University of Cincinnati College of Medicine in 1992. 2010-06-10 4 Jul 2018 - 4:40:59am
Alexandre Lion’s Incubator Charities in Europe (1894–1898) Kelsey Rebovich Alexandre Lion established incubator charities in the late 1890s in France to promote his infant incubator. Lion’s infant incubators kept premature infants warm and improved their chances of survival, but were expensive and not widely used. In order to promote his new technology, Lion displayed incubators that carried premature infants in storefronts and at fairs and expositions throughout Europe. After the public began paying admission to view the infants and incubators, the expositions became incubator charities. Admission fees went directly to the care of the premature infants. 2017-03-14 4 Jul 2018 - 4:40:59am
Alexis Carrel (1873-1944) Adam R. Navis Alexis Carrel was a doctor and researcher who studied tissue cultures. He continued Ross Granville Harrison's research and produced many improvements in the field of tissue culture and surgery. He was the recipient of the 1912 Nobel Prize in Physiology or Medicine for his development of surgical techniques to repair blood vessels. Carrel was born on 28 June 1873 in Sainte-Foy-les-Lyon, France, to Anne-Marie Ricard and Alexis Carrel Billiard. His father died when he was five years old. 2008-02-29 4 Jul 2018 - 4:40:59am
Alexis Carrel's Immortal Chick Heart Tissue Cultures (1912-1946) Lijing Jiang In an effort to develop tissue culture techniques for long-term tissue cultivation, French surgeon and biologist Alexis Carrel, and his associates, produced and maintained a series of chick heart tissue cultures at the Rockefeller Institute in New York City. From 1912 to 1946, this series of chick heart tissue cultures remained alive and dividing. Since the duration of this culture greatly exceeded the normal chick life span, the cells were deemed immortal. 2012-07-03 4 Jul 2018 - 4:40:59am
Alexis Carrel's Tissue Culture Techniques Lijing Jiang Alexis Carrel, the prominent French surgeon, biologist, and 1912 Nobel Prize laureate for Physiology or Medicine, was one of the pioneers in developing and modifying tissue culture techniques. The publicized work of Carrel and his associates at the Rockefeller Institute established the practice of long-term tissue culture for a wide variety of cells. At the same time, some aspects of their work complicated the operational procedures of tissue culture. 2010-06-18 4 Jul 2018 - 4:40:59am
Alfred Day Hershey (1908–1997) Victoria Hernandez During the twentieth century in the United States, Alfred Day Hershey studied phages, or viruses that infect bacteria, and experimentally verified that genes were made of deoxyribonucleic acid, or DNA. Genes are molecular, heritable instructions for how an organism develops. When Hershey started to study phages, scientists did not know if phages contained genes, or whether genes were made of DNA or protein. In 1952, Hershey and his research assistant, Martha Chase, conducted phage experiments that convinced scientists that genes were made of DNA. 2019-04-29 30 Apr 2019 - 10:18:40am
Alfred Henry Sturtevant (1891–1970) Kevin Gleason Alfred Henry Sturtevant studied heredity in fruit flies in the US throughout the twentieth century. From 1910 to 1928, Sturtevant worked in Thomas Hunt Morgan’s research lab in New York City, New York. Sturtevant, Morgan, and other researchers established that chromosomes play a role in the inheritance of traits. In 1913, as an undergraduate, Sturtevant created one of the earliest genetic maps of a fruit fly chromosome, which showed the relative positions of genes along the chromosome. 2017-05-20 4 Jul 2018 - 4:40:59am
Allan Charles Wilson (1934-1991) Dorothy Haskett Allan C. Wilson studied genes, proteins, and body structures of animals and humans in the US during the second half of the twentieth century. Wilson also studied human evolution. Although morphology and behaviors of humans (Homo sapiens) and great apes differ, Wilson found that they have biochemical and genetic similarities. Wilson and his colleagues calculated the time period of humans' and African apes' common ancestor. 2014-07-24 4 Jul 2018 - 4:40:59am
Ameisen: Die heimliche Weltmacht (Ants: Nature’s Secret Power) (2004) Kelle Dhein Ameisen: Die heimliche Weltmacht (Ants: Nature’s Secret Power) is a nature documentary about ants. Wolfgang Thaler wrote, filmed, and directed the film, which focuses on the work of ant researcher Bert 2017-05-23 4 Jul 2018 - 4:40:59am
American Eugenics Society (1926-1972) Rachel Gur-Arie The American Eugenics Society (AES) was established in the US by Madison Grant, Harry H. Laughlin, Henry Crampton, Irving Fisher, and Henry F. Osborn in 1926 to promote eugenics education programs for the US public. The AES described eugenics as the study of improving the genetic composition of humans through controlled reproduction of different races and classes of people. The AES aided smaller eugenic efforts such as the Galton Society in New York, New York, and the 2014-11-22 4 Jul 2018 - 4:40:59am
Amniocentesis Katherine Brind'Amour Amniocentesis is a test used for prenatal diagnosis of inherited diseases, Rh incompatibility, neural tube defects, and lung maturity. Normally performed during the second trimester of a pregnancy, this invasive procedure allows the detection of health problems in the fetus as early as fifteen weeks gestation. Although amniocentesis does carry some significant risks, the medical community commonly accepts it as a safe and useful procedure. 2008-06-04 4 Jul 2018 - 4:40:59am
Amniocentesis Prior to 1980 Kristin Kelley The extraembryonic membranes that surround and originate from the embryos of vertebrates such as birds, reptiles, and mammals are crucial to their development. They are integral to increasing the surface area of the uterus, forming the chorion (which in turn produces the placenta) and the amnion, respectively. The amnion will ultimately surround the embryo in a fluid-filled amniotic cavity. This amniotic fluid, which cushions and protects the fetus and helps prevent the onset of labor, is sampled in amniocentesis to screen for genetic diseases. 2010-09-02 4 Jul 2018 - 4:40:59am
Amphioxus, and the Mosaic Theory of Development (1893), by Edmund Beecher Wilson James Lowe Edmund Beecher Wilson experimented with Amphioxus (Branchiostoma) embryos in 1892 to identify what caused their cells to differentiate into new types of cells during the process of development. Wilson shook apart the cells at early stages of embryonic development, and he observed the development of the isolated cells. He observed that in the normal development of Amphioxus, all three main types of symmetry, or cleavage patterns observed in embryos, could be found. Wilson proposed a hypothesis that reformed the Mosaic Theory associated with Wilhelm Roux in Germany. 2015-03-31 4 Jul 2018 - 4:40:59am
An Atlas of Fertilization and Karyokinesis of the Ovum (1895), by Edmund Beecher Wilson Kevin M. Gleason 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. 2017-04-20 4 Jul 2018 - 4:40:59am

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