In July 2006, scientist Pablo Barreiro and colleagues published "Reproduction Options for HIV-Serodiscordant Couples," in which they recommended methods for human immunodeficiency virus, or HIV, serodiscordant couples to procreate. An HIV-serodiscordant couple is one in which one partner is HIV-positive, meaning they carry HIV, and the other is HIV-negative, meaning they do not carry the virus. HIV is a virus that can spread by sexual contact and it attacks the immune system, causing a person with the virus to have weakened responses to illnesses. Because HIV can transfer from a pregnant woman to a fetus, fetuses conceived in an HIV-serodiscordant relationship could also be HIV-positive. The article "Reproduction Options for HIV-Serodiscordant Couples" offers HIV-serodiscordant couples options on how to procreate without passing HIV on to each other or their offspring.
“Molecular Structure of Nucleic Acids: A Structure for Deoxyribose Nucleic Acid” (1953), by James Watson and Francis Crick
In April 1953, James Watson
and Francis Crick
published "Molecular Structure of Nucleic Acids: A Structure of Deoxyribose Nucleic Acid" or "A Structure for Deoxyribose Nucleic Acid," in the journal Nature
. In the article, Watson and Crick propose a novel structure for deoxyribonucleic acid or DNA. In 1944, Oswald T.
Vaginal Speculum (after 1800)
A vaginal speculum is a medical device that allows physicians and health providers to better view a woman’s cervix
during pelvic exams. Most specula are made of metal and plastic, and physicians insert a portion of the speculum into the patient’s vagina
to separate the vaginal walls. Physicians have used devices to view inside a woman’s vagina
for centuries, but physicians did not begin using what is known as a speculum in the twenty-first century until the 1800s.
Your Baby’s Sex: Now You Can Choose (1970), by David M. Rorvik and Landrum B. Shettles
In the book Your Baby’s Sex: Now You Can Choose
, David Michael Rorvik and Landrum Brewer Shettles
describe methods that couples can use prior to and during conception
that will increase the chances of producing a child of their desired sex. Rorvik, a science writer, and Shettles, an obstetrics and gynecology researcher and physician, co-wrote the book. Shettles developed the methods detailed in the book during the 1960s. Although the authors claim a high success rate, some researchers have contested the validity of the methods proposed in Your Baby’s Sex: Now You Can Choose
“General Considerations for the Clinical Evaluation of Drugs” (1977), by the United States Food and Drug Administration
The United States Food and Drug Administration
, or FDA, published "General Considerations for the Clinical Evaluation of Drugs," in September 1977. The document defined acceptable practices for investigators who studied new drugs. Specifically, the document outlined the common clinical trial methods. Clinical trials are studies to test whether a new drug is safe before doctors can prescribe it to patients. Prior to 1977, the Protection of Human Subjects Rule primarily regulated clinical drug trials, but it did not specify who could and could not be included in clinical trials.
Categorization of Conservative, Semi-Conservative, and Dispersive DNA Replication Theories (1953–1956)
In 1956, Gunther Stent, a scientist at the University of California Berkeley in Berkeley, California, coined the terms conservative, semi-conservative, and dispersive to categorize the prevailing theories about how DNA replicated. Stent presented a paper with Max Delbrück titled "On the Mechanism of DNA Replication" at the McCollum-Pratt Symposium at Johns Hopkins University
in Baltimore, Maryland. In response to James Watson
and Francis Crick´s proposed structure of DNA in 1953, scientists debated how DNA replicated.
Human Papillomavirus (HPV) Strains 16 and 18