Oncology & Cancer

Study reveals lower predictive ability for renal cancer models

(HealthDay)—Prospective validation of existing renal cell carcinoma (RCC) prediction models demonstrates a decrease in their predictive ability, according to a study published online June 19 in the Journal of Clinical Oncology.

Psychology & Psychiatry

Seeing the doctor? Relax, you'll remember more

Some patients feel shame, anxiety or fear immediately before seeing their doctor, making them tense. But if they can relax and become calm, patients will likely pay attention to and better comprehend health messages, suggests ...

Oncology & Cancer

Immunotherapy and HDAC inhibition are anti-cancer besties

Immunotherapies have revolutionized the care of many cancers, teaching the body's own immune cells to recognize and attack tumor cells. Leading the way are drugs known as checkpoint inhibitors, which block a kind of "white ...

Neuroscience

Mood neurons mature during adolescence

Researchers have discovered a mysterious group of neurons in the amygdala—a key center for emotional processing in the brain—that stay in an immature, prenatal developmental state throughout childhood. Most of these cells ...

Ophthalmology

Shedding light on rhodopsin dynamics in the retina

Photoreceptor cells in our eyes can adjust to both weak and strong light levels, but we still don't know exactly how they do it. Emeritus Professor Fumio Hayashi of Kobe University and his colleagues revealed that the photoreceptor ...

Immunology

Vaccine investigators use bacterium's own protein against it

A team of Agricultural Research Service (ARS) and university scientists is investigating a new "ingredient" for use in vaccinating cattle against Johne's disease, a chronic wasting affliction that costs the U.S. dairy industry ...

Immunology

Study explores role of metabolism in immune cell behavior

What makes healthy cells change and become dysfunctional to the point of causing disease? In addition to a disruption in genes that regulate cells, there is another factor in cell misbehavior that involves metabolism, say ...

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Cell (biology)

The cell is the structural and functional unit of all known living organisms. It is the smallest unit of an organism that is classified as living, and is often called the building block of life. Some organisms, such as most bacteria, are unicellular (consist of a single cell). Other organisms, such as humans, are multicellular. (Humans have an estimated 100 trillion or 1014 cells; a typical cell size is 10 µm; a typical cell mass is 1 nanogram.) The largest known cell is an unfertilized ostrich egg cell.

In 1835 before the final cell theory was developed, a Czech Jan Evangelista Purkyně observed small "granules" while looking at the plant tissue through a microscope. The cell theory, first developed in 1839 by Matthias Jakob Schleiden and Theodor Schwann, states that all organisms are composed of one or more cells. All cells come from preexisting cells. Vital functions of an organism occur within cells, and all cells contain the hereditary information necessary for regulating cell functions and for transmitting information to the next generation of cells.

The word cell comes from the Latin cellula, meaning, a small room. The descriptive name for the smallest living biological structure was chosen by Robert Hooke in a book he published in 1665 when he compared the cork cells he saw through his microscope to the small rooms monks lived in.

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