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"The Results of Operations for the Cure of Cancer of the Breast Performed at the Johns Hopkins Hospital from June, 1889, to January, 1894" (1894), by William Stewart Halsted

In 1894, William Stewart Halsted published The Results of Operations for the Cure of Cancer of the Breast Performed at the Johns Hopkins Hospital from June, 1889, to January, 1894, in the medical journal Annals of Surgery. In the article, Halsted describes the results from fifty of his operations on women with breast cancer, performed at Johns Hopkins Hospital in Baltimore, Maryland. Those operations involved a surgical procedure Halsted called radical mastectomy, which consists in removing all of the patient’s breast tissue, chest muscle, and underarm lymph nodes.

Format: Articles

Subject: Publications

The Neuron Doctrine (1860-1895)

The neuron doctrine is a concept formed during the turn of the twentieth century that describes the properties of neurons, the specialized cells that compose the nervous system. The neuron doctrine was one of two major theories on the composition of the nervous system at the time. Advocates of the neuron doctrine claimed that the nervous system was composed of discrete cellular units. Proponents of the alternative reticular theory, on the other hand, argued that the entire nervous system was a continuous network of cells, without gaps or synapses between the cells.

Format: Articles

Subject: Theories

My Father, My Son (1986), by Elmo Zumwalt, Jr., Elmo Zumwalt III, and John Pekkanen

My Father, My Son is a dual autobiography by father and son Elmo Russell Zumwalt Jr. and Elmo Russell Zumwalt III published by Macmillan Publishing Company in 1986, detailing their experiences during the Vietnam War and particularly with Agent Orange, an herbicide used for defoliation and crop destruction during the war. As a commander in the Navy, Zumwalt Jr. ordered the use of Agent Orange in South Vietnam, where Zumwalt III was stationed.

Format: Articles

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

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

Beadle's One Gene-One Enzyme Hypothesis

Object is a digital image with two panes, one on top of the other, both of which picture the area within a cell between the nucleus and the cell membrane. The top pane represent three genes within the cell nucleus, each of which produces a distinct kind of enzyme outside of the nucleus. Those enzymes then function in three distinct kinds of metabolic reactions. The bottom pane represents the same situation, except the second gene is damaged by x-rays and can't produce its enzymes. As a result, two of the three metabolic reactions fail to happen.

Between 1934 and 1945, George Beadle developed a hypothesis that each gene within the chromosomes of organisms each produced one enzyme. Enzymes are types of proteins that can catalyze reactions inside cells, and the figure shows that each enzyme controls a stage in a series of biochemical reactions. The top box in this figure represents a normal process of enzyme production and biochemical reactions, and the bottom box shows how Beadle's experiments affected the normal biochemical process.

Format: Graphics

Subject: Theories, Processes

Chloroplasts

Object is a digital image of a chloroplast. There are two boxes, one atop the other. In the top box is an image of a chloroplast, which is roughly ovoid. A scale bar indicates that the chloroplast is roughly 5 micrometers in length. The outer membrane is colored light green, and the inner membrane is a different shade of light green. The top right parts of the outer and inner membranes are cut away to reveal dozens thylakoids within, which are all dark green and look like tires. They are stacked on top of each other to form ten granums.

Chloroplasts are the organelles in plant and algal cells that conduct photosynthesis. A single chloroplast has an outer membrane and an inner membrane, with an intermembrane space in between. Within the inner membrane, interconnected stacks of thylakoids, called granum, float in a protein rich fluid called the stroma. These thylakoid stacks contain chlorophyll, a pigment which converts sunlight into usable energy for plants and free oxygen from water. The stacks are sites of light reactions within a plant cell.

Format: Graphics

Subject: Theories, Processes

Jelly Fish and Green Fluorescent Protein

Object is a digital image that represents green fluorescent protein at various levels of organization within an organism. On the left of the image is a blue circle, in which there is a jelly fish, with some of its parts aglow. From one such part, a zoom circle juts to the right, in which is represented a strand of DNA from the jelly fish. From that circle, a black arrow points to the right and to a new zoom circle, this one representing the primary amino acid sequence coded for by the DNA sequence and that eventually folds into the protein.

The crystal jellyfish, Aequorea victoria, produces and emits light, called bioluminescence. Its DNA codes for sequence of 238 amino acids that forms a protein called Green Fluorescent Protein (GFP). FP is folded so that a part of the protein, called the chromophore, is located in the center of the protein. The chemical structure of the chromophore emits a green fluorescence when exposed to light in the range of blue to ultraviolet.

Format: Graphics

Subject: Theories, Processes, Organisms, Technologies

William Smellie (1697–1763)

William Smellie helped to incorporate scientific medicine into the process of childbirth in eighteenth century Britain. As a male physician practicing in childbirth and female reproductive health (man-midwife), Smellie developed and taught procedures to treat breech fetuses, which occur when a fetus fails to rotate its head towards the birth canal during delivery. Throughout his career, Smellie compiled a wealth of information about female anatomy in his writings. He modified medical technology such as the obstetrical forceps, an instrument used to maneuver the fetus during childbirth.

Format: Articles

Subject: People, Reproduction

Southern Gastric Brooding Frog

Object is a painted image of two southern gastric brooding frogs facing each other. The one on the left has a transparent middle to reveal tadpoles swimming inside of it. The one on the right shows a more mature juvenile crawling out of the mouth.

The Southern Gastric Brooding Frog (Rheobotrahcus silus) was a frog species that lived in Australia. It was declared extinct in 2002. Once adult males fertilized the eggs of females, the females swallowed their eggs. The stomachs of the females then functioned somewhat like wombs, protecting the eggs while they gestated. Once the eggs developed into juveniles, female frogs performed oral birth and regurgitated their young.

Format: Graphics

Subject: Organisms

DNA and X and Y Chromosomes

Object is a digital image that represents how DNA partly constitutes a Y-chromosome. Image shows different parts of an unbroken strand that begins with the smallest parts on the left side of the image, and eventually forms the Y-chromosome on the right side of the image, so that the chromosome looks like a kite with a long tail. On the left side of the image, a DNA double helix is enlarged to reveal the paired nucleotides within. The width of the helix is 2 nanometers. As the helix continues to the right, it bends downwards, and it gets smaller and seemingly further way from the viewer.

Y-chromosomes exist in the body cells of many kinds of male animals. Found in the nucleus of most living animal cells, the X and Y-chromosomes are condensed structures made of DNA wrapped around proteins called histones. The individual histones bunch into groups that the coiled DNA wraps around called a nucleosome, which are roughly 10 nano-meters (nm) across. The histones bunch together to form a helical fiber (30 nm) that spins into a supercoil (200 nm). During much of a cell's life, DNA exists in the 200 nm supercoil phase.

Format: Graphics

Subject: Theories, Processes

Mitochondria

Object is a digital image of a mitochondrion. There are two boxes, one atop of the other. In the top box is the mitochondrion with a scale bar that indicates that the organelle is 1 micrometer in length. The image depicts the mitochondrion�s outer membrane, which is roughly ovoid in shape and is colored a transparent orange to reveal the inner membrane within, colored red. The top left quarter of the outer membrane and the inner membrane are cut away to reveal the cristae. In the bottom box is a round animal cell, colored teal.

Mitochondria are organelles found in the cytoplasm of eukaryotic cells. They are composed of an outer membrane and an inner membrane. The outer membrane faces the cellular cytoplasm, while the inner membrane folds back on itself multiple times, forming inner folds, called cristae. The space between the two membrane layers is called the intermembrane space, and the space within the inner membrane is called the matrix.

Format: Graphics

Subject: Theories, Processes

Estrogen

This image contains three line-angle formulas of three estrogen molecules: estriol on the left, estradiol in the center, and estrone on the right. The molecules line-angle formulas contain wedged and dashed bonds for three-dimensional geometry or stereochemistry.

The figure depicts three different molecular structures of estrogen found in mammals’ that differ by the arrangement of bonds and side groups. The molecular structures of the three estrogen molecules differ by the arrangement of chemical bonds and side groups attached to the core steroid structure, cholesterol, which contains three cyclohexane rings and one cyclopentane ring.

Format: Graphics

Subject: Theories, Processes, Reproduction

Nuclear Magnetic Resonance Imaging to Visualize Fetal Abnormalities

Nuclear magnetic resonance imaging (MRI) is a technique to create a three-dimensional image of a fetus. Doctors often use MRIs to image a fetuses after an ultrasound has detected an, or has been inconclusive about an, abnormality. In 1983 researchers in Scotland first used MRI to visualize a fetus. MRIs showed a greater level of fetal detail than ultrasound images, and researchers recognized the relevance of this technique as a means to gather information about fetal development and growth.

Format: Articles

Subject: Technologies, Technologies, Reproduction

Neurospora crassa Life Cycle

Object is a digital image with two parts that together show the Neurospora life cycle. The left part shows the asexual reproductive cycle of the mold. The right part shows the sexual reproductive cycle of the mold.

This diagram shows the life cycle of Neurospora crassa, a mold that grows on bread. N. crassa can reproduce through an asexual cycle or a sexual cycle. The asexual cycle (colored as a purple circle), begins in this figure with (1a) vegetative mycelium, which are strands of mature fungus. Some of the strands form bulbs (2a) in a process called conidiation. From those bulbs develop the conidia, which are spores. Next, (3a) a single conidium separates from its strand and elongates until it forms mycelium.

Format: Graphics

Subject: Organisms, Processes, Theories

State v. New Times, INC (1973)

In the 1973 case State v. New Times, INC, the Arizona Court of Appeals in Phoenix, Arizona, ruled that Arizona Revised Statutes 13-211, 13-212, and 13-213, collectively called the Arizona abortion statutes, were unconstitutional. The statues made it illegal for anyone to receive, provide, or advertise abortion services. The Arizona Court of Appeals reviewed a case in which a city court in Tempe, Arizona, convicted the New Times, a newspaper headquartered in Phoenix, Arizona, of advertising abortion.

Format: Articles

Subject: Legal

"The Premenstrual Syndrome" (1953), by Raymond Greene and Katharina Dalton

In 1953, Raymond Greene and Katharina Dalton, who were doctors in the UK, published The Premenstrual Syndrome in the British Medical Journal. In their article, Dalton and Greene established the term premenstrual syndrome (PMS). The authors defined PMS as a cluster of symptoms that include bloating, breast pain, migraine-headache, fatigue, anxiety, depression, and irritability. The article states that the symptoms begin one to two weeks before menstruation during the luteal phase of the menstrual cycle, and they disappear upon the onset of the menstrual period.

Format: Articles

Subject: Publications, Reproduction

Pearl Mao Tang (1922– )

A licensed obstetrician and gynecologist, Pearl Tang worked to improve the health of women and children in Maricopa County, Arizona, during the twentieth and twenty-first centuries. Her work with the Maricopa County Health Department ranged from immunizations to preventing cervical cancer. Tang obtained federal grants and community support to establish various child and maternal health clinics throughout Maricopa County as chief of the Maricopa County Bureau of Maternal and Child Health.

Format: Articles

Subject: People

Planned Parenthood Committee of Phoenix v. Maricopa County (1962)

In the 1962 case Planned Parenthood Committee of Phoenix v. Maricopa County, the Arizona Supreme Court ruled that Arizona Revised Statute 13-213, which banned the public advertising of contraceptive or abortion medication or services, was constitutional. However, the court also ruled that that Arizona Revised Statute 13-213 did not apply to Planned Parenthood's distribution of contraceptive information, allowing Planned Parenthood to continue distributing the information.

Format: Articles

Subject: Legal

Texas Medical Providers Performing Abortion Services v. Lakey (2012)

In the 2012 case Texas Medical Providers Performing Abortion Services v. David Lakey, a US appeals court ruled as constitutional a Texas law that required abortion providers in the state to show women receiving abortions the ultrasound images of their fetuses. The law also required providers to describe the sounds of the fetuses' nascent hearts. In doing so, the court set precedent that ultrasound readings are necessary medical information for pregnant women seeking abortions, increasing the wait-period for women seeking abortions.

Format: Articles

Subject: Legal

The Hyde Amendment of 1976

In 1976, the US Congress passed the Hyde Amendment, which banned the use of federal funding to pay for abortions through Medicaid. In 1976, Illinois Congressman Henry J. Hyde proposed the amendment to the Departments of Labor and Health, Education, and Welfare, Appropriation Act of 1977. In 1980, the US Supreme Court in Harris v. McRae (1980) upheld the constitutionality of the Hyde Amendment.

Format: Articles

Subject: Legal

Harris v. McRae (1980)

On 30 June 1980, in a five to four decision, the US Supreme Court ruled in the Case Harris v. McRae that the Hyde Amendment of 1976 did not violate the US Constitution. The Hyde Amendment banned the use of federal funding to pay for any abortion services. The US Supreme Court's decision in Harris v. McRae overturned the decision of McRae v. Califano (1980), in which the US District Court for the Eastern District of New York had ruled that the funding restrictions established by the Hyde Amendment violated the US Constitution. After the US Supreme Court's ruling in Harris v.

Format: Articles

Subject: Legal

Beal v. Doe (1977)

In the case of Beal v. Doe, tried in 1977, the US Supreme Court ruled that states could constitutionally restrict money from Medicaid from funding elective abortions. After the 1973 case Roe v. Wade, in which the US Supreme Court had ruled women have the rights to terminate pregnancies within the first trimester, the state of Pennsylvania passed legislation that restricted the use of Medicaid funds for abortion procedures. In 1977, several Medicaid eligible women who were unable to receive coverage for a non-therapeutic abortion brought a case against Frank S.

Format: Articles

Subject: Legal

1901 Arizona Comstock Law

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.

Format: Articles

Subject: Legal

“Family Limitations” (1914), by Margaret Higgins Sanger

In 1914, Margaret Sanger published “Family Limitations,” a pamphlet describing six different types of contraceptive methods. At the time Sanger published the pamphlet, the federal Comstock Act of 1873 had made distributing contraceptive and abortion information through the US postal service illegal. The Comstock Act classified contraceptive information as obscene and limited the amount of information available to individuals about preventing pregnancies.

Format: Articles

Subject: Publications