- 行业: Printing & publishing
- Number of terms: 178089
- Number of blossaries: 0
- Company Profile:
McGraw Hill Financial, Inc. is an American publicly traded corporation headquartered in Rockefeller Center in New York City. Its primary areas of business are financial, publishing, and business services.
A prosimian primate in the family Daubentoniidae inhabiting Madagascar. It is the most endangered of all mammals in Madagascar. A member of the order Primates and the suborder Prosimiae, aye-ayes (<i>Daubentonia madagascariensis</i>) (see <b>illus.</b>) are most closely related to the lemurs.
Industry:Science
A prostrate hardy perennial crucifer of European origin belonging to the plant order Capparales. Watercress (<i>Nasturtium officinale</i>) is generally grown in flooded soil beds and used for salads and garnishing. Propagation is by seed or stem cuttings. High soil moisture is necessary. Leafy stems are cut usually 180 days after planting. Virginia is an important producing state.
Industry:Science
A protective device which is connected between an electrical conductor and the ground with the intent of limiting the magnitude of transient overvoltages on equipment.
Industry:Science
A protective housing for radar, satellite communications, or similar antennas, often spherical but sometimes shaped to satisfy aerodynamic or other requirements of the installation. Radomes are designed to satisfy both electromagnetic and mechanical requirements.
Industry:Science
A protein comprising 167 amino acids that is important in the regulation of body weight, metabolism, and reproduction. Leptin was discovered in 1994, when it was identified as the missing protein in mice with a spontaneous single-gene defect that caused obesity. These <i>ob/ob</i> mice were very obese, had many of the metabolic abnormalities associated with obesity, and were infertile. However, when leptin levels were examined in other animal models of obesity and in obese humans, the levels were found to be elevated and not low or absent (as in the <i>ob/ob</i> mice). Thus, general obesity (not due to leptin deficiency) has been termed a leptin-resistant state. Since these initial findings, the biology of leptin has proven to be more complex than originally thought.
Industry:Science
A protein extracted after partial hydrolysis of collagenous raw material from the skin, white connective tissue, and bone of animals. It is a linear polymer of amino acids, most often with repeating glycine-proline-proline and glycine-proline-hydroxyproline sequences in the polypeptide linkages. Gelatin gives positive test for hydroxyproline, and yields amino acid components upon complete hydrolysis.
Industry:Science
A protein in the cell nucleus that mediates the actions of retinoids (the natural and synthetic analogs of vitamin A) by regulating the rates of transcription of retinoid-responsive genes. Retinoid receptors facilitate the normal biological actions of vitamin A within the body. Thus, they play an important role in the maintenance of normal growth and development; in the immune response; in male and female reproduction; in blood cell development; and in the maintenance of healthy skin and bones; and ultimately in the general good health of the organism.
Industry:Science
A protein produced by the bioluminescent jellyfish <i>Aequorea victoria</i> that fluoresces in the lower green portion of the visible spectrum. The gene for green fluorescent protein (GFP) has been isolated, and the protein has been extensively characterized biochemically and found useful in biological research. After synthesis of GFP, three of its amino acids undergo a self-catalyzed reaction that produces an internal fluorophore (fluorescent molecule). The protein does not require a specific cellular environment to become fluorescent and can be artificially expressed in cell types as diverse as bacterial, plant, and animal cells. It can be attached to other proteins of interest using recombinant DNA techniques, making it possible to easily trace the synthesis, location, and movement of these proteins in single living cells using conventional fluorescence microscopy.
Industry:Science
A proteolytic enzyme found in the gastric juice of mammals, birds, reptiles, and fish. It is formed from a precursor, pepsinogen, which is found in the stomach mucosa. Pepsinogen is converted to pepsin either by hydrochloric acid, naturally present in the stomach, or by pepsin itself. A pepsin inhibitor, peptide, remains attached to the pepsin molecule at pH values above 5.0, preventing activation of the enzyme. The approximate molecular weight of pepsin is 34,500 and that of pepsinogen is 42,600. Maximum activity occurs at pH 1.8, and broad specificity for peptide bonds is demonstrated.
Industry:Science
A proteolytic enzyme that can digest many proteins through the process of hydrolysis. Plasmin is found in plasma in the form of plasminogen, which is an inert precursor or zymogen; one site of synthesis is the liver. Plasma also contains inhibitors that limit either the transformation of plasminogen to plasmin (plasminogen activator inhibitors) or the action of plasmin (principally α<sub>2</sub>-antiplasmin and α<sub>2</sub>-macro-globulin).
Industry:Science
