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45 CFR 46: Protection of Human Subjects under United States Law (1974)

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.

Format: Articles

Subject: Legal

Florence Rena Sabin (1871-1953)

Florence Rena Sabin had successful careers as both a researcher and public health reformer. When Johns Hopkins University Medical School opened, accepting women and men on the same basis, Sabin was one of the first to enter. After the successful completion of her MD degree, Sabin went on to become the first female faculty member and later full-time professor at Johns Hopkins.

Format: Articles

Subject: People

"The Multi-Dimensional Human Embryo"

The Multi-Dimensional Human Embryo website (http://embryo.soad.umich.edu/) is a publicly accessible online database of the first three-dimensional images and animations of human embryos during different stages of development. Both the images and animations were created using magnetic resonance microscopy and compiled for easy access.

Format: Articles

Subject: Outreach, Organizations

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

"Generation of Germline-Competent Induced Pluripotent Stem Cells" (2007), by Keisuke Okita, Tomoko Ichisaka, and Shinya Yamanaka

In the July 2007 issue of Nature, Keisuke Okita, Tomoko Ichisaka, and Shinya Yamanaka added to the new work on induced pluripotent stem cells (iPSCs) with their "Generation of Germline-Competent Induced Pluripotent Stem Cells" (henceforth abbreviated "Generation"). The authors begin the paper by noting their desire to find a method for inducing somatic cells of patients to return to a pluripotent state, a state from which the cell can differentiate into any type of tissue but cannot form an entire organism.

Format: Articles

Subject: Publications

Hematopoietic Stem Cell Transplantation

The purpose of regenerative medicine, especially tissue engineering, is to replace damaged tissue with new tissue that will allow the body to resume normal function. The uniqueness of tissue engineering is that it can restore normal structure in addition to repairing tissue function, and is often accomplished using stem cells. The first type of tissue engineering using stem cells was hematopoietic stem cell transplantation (HSCT), a surgical procedure in which hematopoietic stem cells (HSCs) are infused into a host to treat a variety of blood diseases, cancers, and immunodeficiencies.

Format: Articles

Subject: Technologies

Reassessment of Carrel's Immortal Tissue Culture Experiments

In the 1910s, Alexis Carrel, a French surgeon and biologist, concluded that cells are intrinsically immortal. His claim was based on chick-heart tissue cultures in his laboratory that seemed to be able to proliferate forever. Carrel's ideas about cellular immortality convinced his many contemporaries that cells could be maintained indefinitely. In the 1960s, however, Carrel's thesis about cell immortality was put into question by the discovery that human diploid cells can only proliferate for a finite period.

Format: Articles

Subject: Processes, Theories

"Generation of Induced Pluripotent Stem Cells without Myc from Mouse and Human Fibroblasts" (2007), by Masato Nakagawa et al.

In November 2007, Masato Nakagawa, along with a number of other researchers including Kazutoshi Takahashi, Keisuke Okita, and Shinya Yamanaka, published "Generation of Induced Pluripotent Stem Cells without Myc from Mouse and Human Fibroblasts" (abbreviated "Generation") in Nature. In "Generation," the authors point to dedifferentiation of somatic cells as an avenue for generating pluripotent stem cells useful for treating specific patients and diseases.

Format: Articles

Subject: Publications, Experiments

Alexis Carrel's Tissue Culture Techniques

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.

Format: Articles

Subject: Technologies

"Contributions to the Development of the Embryo. On the Artificial Production of One of the First Two Blastomeres, and the Later Development (Postgeneration) of the Missing Half of the Body" (1888), by Wilhelm Roux

Wilhelm Roux was an influential figure in the early history of experimental embryology. Although he originally studied medicine, he was invited to be a Privatdozentur, or unsalaried lecturer, at the Anatomical Institute in Breslau (Wroclaw), Poland, in 1879. He spent the next ten years at this institute, working his way from Dozent to associate professor and finally, in 1889, to director for his own institute, Institut für Entwicklungsgeschichte, or Institute for Developmental History and Mechanics.

Format: Articles

Subject: Experiments

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

Bowen v. American Hospital Association (1986)

The 1986 US Supreme Court decision Bowen v. American Hospital Association rejected the federal government's use of Section 504 of the Rehabilitation Act of 1973 to intervene in a hospital's treatment for neonates born with severe congenital defects. This case set a precedent for the role of government involvement in cases where parents refused consent for care of disabled newborns.

Format: Articles

Subject: Legal, Reproduction

"Developmental Effects of Endocrine-Disrupting Chemicals in Wildlife and Humans" (1993), by Theo Colborn, Frederick S. vom Saal, and Ana M. Soto

Developmental Effects of Endocrine-Disrupting Chemicals in Wildlife and Humans, was published in 1993 in Environmental Health Perspectives. In the article, the authors present an account of two decades' worth of scientific research that describes the effects of certain pollutants on the health of wildlife, domestic animals, and humans, particularly when exposure takes place during embryonic growth. The term endocrine disruptor was coined in the article to describe the chemical pollutants that target the development and function of the endocrine system.

Format: Articles

Subject: Publications

Jeter v. Mayo Clinic Arizona [Brief] (2005)

In Arizona, statutes that protect persons, such as the wrongful death statute, will not be interpreted by the courts to grant personhood status to frozen embryos. The legislature may grant such protection in the statute if it chooses to do so by explicitly defining the word person to include frozen embryos.

Format: Articles

Subject: Legal, Reproduction

Kass v. Kass [Brief] (1998)

In a case of first impression in the state of New York, the highest state court decided that a priori written agreement between progenitors of frozen embryos regarding the disposition of their "pre-zygotes" in the event of divorce is binding. By copying the general result arrived at by the Tennessee Supreme Court in Davis v. Davis in 1992, the New York court magnified the weight of authority in favor of upholding prior written agreements for in vitro fertilization practices.

Format: Articles

Subject: Legal, Reproduction

"Selective Growth Stimulating Effects of Mouse Sarcoma on the Sensory and Sympathetic Nervous System of the Chick Embryo" (1951), by Rita Levi-Montalcini and Viktor Hamburger

In "Selective Growth Stimulating Effects of Mouse Sarcoma on the Sensory and Sympathetic Nervous System of the Chick Embryo," Rita Levi-Montalcini and Viktor Hamburger explored the effects of two nerve growth stimulating tumors; mouse sarcomas 180 and 37. This experiment led to the discovery that nerve growth factor was a diffusible chemical and later to discoveries that the compound was a protein. Although this paper was an important step in the discovery of nerve growth factor, the term "nerve growth factor" was not used in this paper.

Format: Articles

Subject: Experiments

"Interspecific Chimeras in Mammals: Successful Production of Live Chimeras Between Mus musculus and Mus caroli" (1980), by Janet Rossant and William I. Frels

In 1980 Janet Rossant and William I. Frels published their paper, "Interspecific Chimeras in Mammals: Successful Production of Live Chimeras Between Mus musculus and Mus caroli," in Science. Their experiment involved the first successful creation of interspecific mammalian chimeras. Mammalian chimeras are valuable for studying early embryonic development. However, in earlier studies, clonal analysis was restricted by the lack of a cell marker, present at all times, that makes a distinction between the two parental cell types in situ.

Format: Articles

Subject: Experiments

"A Series of Normal Stages in the Development of the Chick Embryo" (1951), by Viktor Hamburger and Howard L. Hamilton

The developmental stages of the chick embryo were examined by Viktor Hamburger and Howard L. Hamilton in "A Series of Normal Stages in the Development of the Chick Embryo," published in the Journal of Morphology in 1951. These stages were published to standardize the development of the chick based on varying laboratory conditions and genetic differences. The stages Hamburger and Hamilton assigned were determined by the visible features of the chick embryo.

Format: Articles

Subject: Experiments

Wilhelm His, Sr. (1831-1904)

Wilhelm His, Sr. was born on 9 July 1831 in Basel, Switzerland, to Katharina La Roche and Eduard His. He began his medical studies at Basel in 1849 and later transferred to the University of Bern during the winter semester of 1849-1850. A year later, His arrived at the University of Berlin, where he studied under Johannes Müller and Robert Remak. For his clinical training, His attended the University of Würzburg from 1852-1853.

Format: Articles

Subject: People

"Versuche zur Analyse der Induktionsmittel in der Embryonalentwicklung" (1932), by Hermann Bautzmann, Johannes Holtfreter, Otto Mangold, and Hans Spemann

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.

Format: Articles

Subject: Experiments

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

Pope Innocent XI (1611-1689)

Pope Innocent XI, born Benedetto Odescalchi, made considerable contributions to the Roman Catholic approach to embryology by condemning several propositions on liberal moral theology in 1679, including two related to abortion and ensoulment. His rejection of these principles strengthened the Church's stance against abortion and for the idea of "hominization," meaning the presence of human qualities before birth.

Format: Articles

Subject: People, Religion, Reproduction

"Experimental Chimeras' Removal of Reproductive Barrier Between Sheep and Goat" (1984), by Sabine Meinecke-Tillmann and Burkhard Meinecke

In 1984 Sabine Meinecke-Tillmann and Burkhard Meinecke published their article "Experimental Chimeras - Removal of Reproductive Barrier Between Sheep and Goat" in Nature. Their study conquered the reproductive barrier between sheep and goats through embryo manipulation. Their article appeared in Nature on the same day that a similar experiment, conducted by Carole Fehilly, Steen Willadsen, and Elizabeth Tucker was published regarding reproductive barriers between sheep and goats.

Format: Articles

Subject: Experiments

Laparoscopy

Laparoscopy, a subfield of endoscopy, is a minimally invasive surgical procedure used to examine and operate on the internal organs of the abdomen through a small incision in the abdominal wall. The term "laparoscopy" is derived from two Greek words: laparo, meaning the soft space between hips and ribs, and skopie, meaning to examine. Today laparoscopy has broad clinical applications including for diagnosis, fertility procedures, visual representation, and surgery.

Format: Articles

Subject: Technologies, Reproduction

Samuel Randall Detwiler (1890-1957)

Samuel Randall Detwiler was an embryologist who studied neural development in embryos and vertebrate retinas. He discovered evidence for the relationship between somites and spinal ganglia, that transplanted limbs can be controlled by foreign ganglia, and the plasticity of ganglia in response to limb transplantations. He also extensively studied vertebrate retinas during and after embryonic development.

Format: Articles

Subject: People