1-Alkyl-2-acetylglycerophosphocholine Esterase: A lipoprotein-associated PHOSPHOLIPASE A2 which modulates the action of PLATELET ACTIVATING FACTOR by hydrolyzing the SN-2 ester bond to yield the biologically inactive lyso-platelet-activating factor. It has specificity for phospholipid substrates with short-chain residues at the SN-2 position, but inactive against long-chain phospholipids. Deficiency in this enzyme is associated with many diseases including ASTHMA, and HYPERCHOLESTEROLEMIA.EsterasesCarboxylic Ester Hydrolases: Enzymes which catalyze the hydrolysis of carboxylic acid esters with the formation of an alcohol and a carboxylic acid anion.Naphthol AS D Esterase: Hydrolytic enzyme activity used as a histocytochemical test for the presence of esterases in tissue. Substrate used is 3-hydroxy-4'-nitro-2-naphthanilide chloroacetate (naphthol AS-D).Sterol Esterase: An enzyme that catalyzes the hydrolysis of CHOLESTEROL ESTERS and some other sterol esters, to liberate cholesterol plus a fatty acid anion.Acetylesterase: An enzyme that catalyzes the conversion of acetate esters and water to alcohols and acetate. EC Carboxylesterase is a serine-dependent esterase with wide substrate specificity. The enzyme is involved in the detoxification of XENOBIOTICS and the activation of ester and of amide PRODRUGS.EstersIsoflurophate: A di-isopropyl-fluorophosphate which is an irreversible cholinesterase inhibitor used to investigate the NERVOUS SYSTEM.Alkylation: The covalent bonding of an alkyl group to an organic compound. It can occur by a simple addition reaction or by substitution of another functional group.Atlases as Topic: Collections of illustrative plates, charts, etc., usually with explanatory captions.Proteomics: The systematic study of the complete complement of proteins (PROTEOME) of organisms.Lissencephaly: A "smooth brain" malformation of the CEREBRAL CORTEX resulting from abnormal location of developing neurons during corticogenesis. It is characterized by an absence of normal convoluted indentations on the surface of the brain (agyria), or fewer and shallower indentations (pachygryia). There is a reduced number of cortical layers, typically 4 instead of 6, resulting in a thickened cortex, and reduced cerebral white matter that is a reversal of the normal ratio of cerebral white matter to cortex.Cervical Atlas: The first cervical vertebra.beta Catenin: A multi-functional catenin that participates in CELL ADHESION and nuclear signaling. Beta catenin binds CADHERINS and helps link their cytoplasmic tails to the ACTIN in the CYTOSKELETON via ALPHA CATENIN. It also serves as a transcriptional co-activator and downstream component of WNT PROTEIN-mediated SIGNAL TRANSDUCTION PATHWAYS.Immunohistochemistry: Histochemical localization of immunoreactive substances using labeled antibodies as reagents.Bibliometrics: The use of statistical methods in the analysis of a body of literature to reveal the historical development of subject fields and patterns of authorship, publication, and use. Formerly called statistical bibliography. (from The ALA Glossary of Library and Information Science, 1983)Publications: Copies of a work or document distributed to the public by sale, rental, lease, or lending. (From ALA Glossary of Library and Information Science, 1983, p181)Publishing: "The business or profession of the commercial production and issuance of literature" (Webster's 3d). It includes the publisher, publication processes, editing and editors. Production may be by conventional printing methods or by electronic publishing.Research: Critical and exhaustive investigation or experimentation, having for its aim the discovery of new facts and their correct interpretation, the revision of accepted conclusions, theories, or laws in the light of newly discovered facts, or the practical application of such new or revised conclusions, theories, or laws. (Webster, 3d ed)Gastroenterology: A subspecialty of internal medicine concerned with the study of the physiology and diseases of the digestive system and related structures (esophagus, liver, gallbladder, and pancreas).Biomedical Research: Research that involves the application of the natural sciences, especially biology and physiology, to medicine.PubMed: A bibliographic database that includes MEDLINE as its primary subset. It is produced by the National Center for Biotechnology Information (NCBI), part of the NATIONAL LIBRARY OF MEDICINE. PubMed, which is searchable through NLM's Web site, also includes access to additional citations to selected life sciences journals not in MEDLINE, and links to other resources such as the full-text of articles at participating publishers' Web sites, NCBI's molecular biology databases, and PubMed Central.Academies and Institutes: Organizations representing specialized fields which are accepted as authoritative; may be non-governmental, university or an independent research organization, e.g., National Academy of Sciences, Brookings Institution, etc.Risk Factors: An aspect of personal behavior or lifestyle, environmental exposure, or inborn or inherited characteristic, which, on the basis of epidemiologic evidence, is known to be associated with a health-related condition considered important to prevent.Phospholipases A2: Phospholipases that hydrolyze the acyl group attached to the 2-position of PHOSPHOGLYCERIDES.Myocardial Infarction: NECROSIS of the MYOCARDIUM caused by an obstruction of the blood supply to the heart (CORONARY CIRCULATION).Follow-Up Studies: Studies in which individuals or populations are followed to assess the outcome of exposures, procedures, or effects of a characteristic, e.g., occurrence of disease.BenzaldehydesProspective Studies: Observation of a population for a sufficient number of persons over a sufficient number of years to generate incidence or mortality rates subsequent to the selection of the study group.17-Ketosteroids: Steroids that contain a ketone group at position 17.Barth Syndrome: Rare congenital X-linked disorder of lipid metabolism. Barth syndrome is transmitted in an X-linked recessive pattern. The syndrome is characterized by muscular weakness, growth retardation, DILATED CARDIOMYOPATHY, variable NEUTROPENIA, 3-methylglutaconic aciduria (type II) and decreases in mitochondrial CARDIOLIPIN level. Other biochemical and morphological mitochondrial abnormalities also exist.Periodicals as Topic: A publication issued at stated, more or less regular, intervals.Bulbo-Spinal Atrophy, X-Linked: An X-linked recessive form of spinal muscular atrophy. It is due to a mutation of the gene encoding the ANDROGEN RECEPTOR.Bronchopneumonia: Inflammation of the lung parenchyma that is associated with BRONCHITIS, usually involving lobular areas from TERMINAL BRONCHIOLES to the PULMONARY ALVEOLI. The affected areas become filled with exudate that forms consolidated patches.TracheitisHyaline Membrane Disease: A respiratory distress syndrome in newborn infants, usually premature infants with insufficient PULMONARY SURFACTANTS. The disease is characterized by the formation of a HYALINE-like membrane lining the terminal respiratory airspaces (PULMONARY ALVEOLI) and subsequent collapse of the lung (PULMONARY ATELECTASIS).Influenza A virus: The type species of the genus INFLUENZAVIRUS A that causes influenza and other diseases in humans and animals. Antigenic variation occurs frequently between strains, allowing classification into subtypes and variants. Transmission is usually by aerosol (human and most non-aquatic hosts) or waterborne (ducks). Infected birds shed the virus in their saliva, nasal secretions, and feces.Hemagglutinin Glycoproteins, Influenza Virus: Membrane glycoproteins from influenza viruses which are involved in hemagglutination, virus attachment, and envelope fusion. Fourteen distinct subtypes of HA glycoproteins and nine of NA glycoproteins have been identified from INFLUENZA A VIRUS; no subtypes have been identified for Influenza B or Influenza C viruses.Influenza, Human: An acute viral infection in humans involving the respiratory tract. It is marked by inflammation of the NASAL MUCOSA; the PHARYNX; and conjunctiva, and by headache and severe, often generalized, myalgia.Lung Diseases, Interstitial: A diverse group of lung diseases that affect the lung parenchyma. They are characterized by an initial inflammation of PULMONARY ALVEOLI that extends to the interstitium and beyond leading to diffuse PULMONARY FIBROSIS. Interstitial lung diseases are classified by their etiology (known or unknown causes), and radiological-pathological features.Proprotein Convertases: Proteolytic enzymes that are involved in the conversion of protein precursors such as peptide prohormones into PEPTIDE HORMONES. Some are ENDOPEPTIDASES, some are EXOPEPTIDASES.Cholesterol, LDL: Cholesterol which is contained in or bound to low density lipoproteins (LDL), including CHOLESTEROL ESTERS and free cholesterol.Serine Endopeptidases: Any member of the group of ENDOPEPTIDASES containing at the active site a serine residue involved in catalysis.Receptors, LDL: Receptors on the plasma membrane of nonhepatic cells that specifically bind LDL. The receptors are localized in specialized regions called coated pits. Hypercholesteremia is caused by an allelic genetic defect of three types: 1, receptors do not bind to LDL; 2, there is reduced binding of LDL; and 3, there is normal binding but no internalization of LDL. In consequence, entry of cholesterol esters into the cell is impaired and the intracellular feedback by cholesterol on 3-hydroxy-3-methylglutaryl CoA reductase is lacking.Subtilisin: A serine endopeptidase isolated from Bacillus subtilis. It hydrolyzes proteins with broad specificity for peptide bonds, and a preference for a large uncharged residue in P1. It also hydrolyzes peptide amides. (From Enzyme Nomenclature, 1992) EC The principal sterol of all higher animals, distributed in body tissues, especially the brain and spinal cord, and in animal fats and oils.Hyperlipoproteinemia Type II: A group of familial disorders characterized by elevated circulating cholesterol contained in either LOW-DENSITY LIPOPROTEINS alone or also in VERY-LOW-DENSITY LIPOPROTEINS (pre-beta lipoproteins).Genome, Helminth: The genetic complement of a helminth (HELMINTHS) as represented in its DNA.Caenorhabditis: A genus of small free-living nematodes. Two species, CAENORHABDITIS ELEGANS and C. briggsae are much used in studies of genetics, development, aging, muscle chemistry, and neuroanatomy.Software: Sequential operating programs and data which instruct the functioning of a digital computer.Internet: A loose confederation of computer communication networks around the world. The networks that make up the Internet are connected through several backbone networks. The Internet grew out of the US Government ARPAnet project and was designed to facilitate information exchange.Databases, Genetic: Databases devoted to knowledge about specific genes and gene products.Caenorhabditis elegans: A species of nematode that is widely used in biological, biochemical, and genetic studies.User-Computer Interface: The portion of an interactive computer program that issues messages to and receives commands from a user.