Perciformes: The most diversified of all fish orders and the largest vertebrate order. It includes many of the commonly known fish such as porgies, croakers, sunfishes, dolphin fish, mackerels, TUNA, etc.Cichlids: Common name for perch-like fish of the family Cichlidae, belonging to the suborder Labroidei, order PERCIFORMES.Rivers: Large natural streams of FRESH WATER formed by converging tributaries and which empty into a body of water (lake or ocean).Fishes: A group of cold-blooded, aquatic vertebrates having gills, fins, a cartilaginous or bony endoskeleton, and elongated bodies covered with scales.BrazilPhylogeny: The relationships of groups of organisms as reflected by their genetic makeup.DNA, Mitochondrial: Double-stranded DNA of MITOCHONDRIA. In eukaryotes, the mitochondrial GENOME is circular and codes for ribosomal RNAs, transfer RNAs, and about 10 proteins.Sequence Analysis, DNA: A multistage process that includes cloning, physical mapping, subcloning, determination of the DNA SEQUENCE, and information analysis.Sense Organs: Specialized organs adapted for the reception of stimuli by the NERVOUS SYSTEM.Antarctic Regions: The continent lying around the South Pole and the southern waters of the Atlantic, Pacific, and Indian Oceans. It includes the Falkland Islands Dependencies. (From Webster's New Geographical Dictionary, 1988, p55)Periodicals as Topic: A publication issued at stated, more or less regular, intervals.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.BooksPublishing: "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.Mediterranean SeaAtlantic OceanMicrosatellite Repeats: A variety of simple repeat sequences that are distributed throughout the GENOME. They are characterized by a short repeat unit of 2-8 basepairs that is repeated up to 100 times. They are also known as short tandem repeats (STRs).Genetic Variation: Genotypic differences observed among individuals in a population.Cyprinodontiformes: An order of fish with eight families and numerous species of both egg-laying and livebearing fish. Families include Cyprinodontidae (egg-laying KILLIFISHES;), FUNDULIDAEl; (topminnows), Goodeidae (Mexican livebearers), Jenynsiidae (jenynsiids), Poeciliidae (livebearers), Profundulidae (Middle American killifishes), Aplocheilidae, and Rivulidae (rivulines). In the family Poeciliidae, the guppy and molly belong to the genus POECILIA.MexicoTilapia: A freshwater fish used as an experimental organism and for food. This genus of the family Cichlidae (CICHLIDS) inhabits Central and South America (one species extends north into Texas), West Indies, Africa, Madagascar, Syria, and coastal India.Lakes: Inland bodies of still or slowly moving FRESH WATER or salt water, larger than a pond, and supplied by RIVERS and streams.Euglena gracilis: A species of fresh-water, flagellated EUKARYOTES in the phylum EUGLENIDA.Osmoregulation: The response of cells in sensing a difference in OSMOTIC PRESSURE between the inside and outside of the cell. This response includes signaling from osmotic sensors to activate transcription factors, which in turn regulate the expression of osmocompensatory genes, all functioning to maintain CELL VOLUME and the water concentration inside the cells.Linkage Disequilibrium: Nonrandom association of linked genes. This is the tendency of the alleles of two separate but already linked loci to be found together more frequently than would be expected by chance alone.Living Wills: Written, witnessed declarations in which persons request that if they become disabled beyond reasonable expectation of recovery, they be allowed to die rather than be kept alive by extraordinary means. (Bioethics Thesaurus)Alleles: Variant forms of the same gene, occupying the same locus on homologous CHROMOSOMES, and governing the variants in production of the same gene product.Software: Sequential operating programs and data which instruct the functioning of a digital computer.Gene Frequency: The proportion of one particular in the total of all ALLELES for one genetic locus in a breeding POPULATION.Taq Polymerase: A heat stable DNA-DIRECTED DNA POLYMERASE from the bacteria Thermus aquaticus. It is widely used for the amplification of genes through the process of POLYMERASE CHAIN REACTION. EC 2.7.7.-.Garcinia kola: A plant species of the family CLUSIACEAE. The common name of 'Bitter Kola' is sometimes also used to refer to COLA.Polymerase Chain Reaction: In vitro method for producing large amounts of specific DNA or RNA fragments of defined length and sequence from small amounts of short oligonucleotide flanking sequences (primers). The essential steps include thermal denaturation of the double-stranded target molecules, annealing of the primers to their complementary sequences, and extension of the annealed primers by enzymatic synthesis with DNA polymerase. The reaction is efficient, specific, and extremely sensitive. Uses for the reaction include disease diagnosis, detection of difficult-to-isolate pathogens, mutation analysis, genetic testing, DNA sequencing, and analyzing evolutionary relationships.Molecular Sequence Data: Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.ParaguayAnimal Fins: Membranous appendage of fish and other aquatic organisms used for locomotion or balance.Encyclopedias as Topic: Works containing information articles on subjects in every field of knowledge, usually arranged in alphabetical order, or a similar work limited to a special field or subject. (From The ALA Glossary of Library and Information Science, 1983)Abdominal Muscles: Muscles forming the ABDOMINAL WALL including RECTUS ABDOMINIS, external and internal oblique muscles, transversus abdominis, and quadratus abdominis. (from Stedman, 25th ed)Coral Reefs: Marine ridges composed of living CORALS, coral skeletons, calcareous algae, and other organisms, mixed with minerals and organic matter. They are found most commonly in tropical waters and support other animal and plant life.Invertebrates: Animals that have no spinal column.Copyright: It is a form of protection provided by law. In the United States this protection is granted to authors of original works of authorship, including literary, dramatic, musical, artistic, and certain other intellectual works. This protection is available to both published and unpublished works. (from Circular of the United States Copyright Office, 6/30/2008)Gram-Positive Endospore-Forming Bacteria: Bacteria that form endospores and are gram-positive. Representative genera include BACILLUS; CLOSTRIDIUM; MICROMONOSPORA; SACCHAROPOLYSPORA; and STREPTOMYCES.Computer Security: Protective measures against unauthorized access to or interference with computer operating systems, telecommunications, or data structures, especially the modification, deletion, destruction, or release of data in computers. It includes methods of forestalling interference by computer viruses or so-called computer hackers aiming to compromise stored data.Confidentiality: The privacy of information and its protection against unauthorized disclosure.Privacy: The state of being free from intrusion or disturbance in one's private life or affairs. (Random House Unabridged Dictionary, 2d ed, 1993)Natural Language Processing: Computer processing of a language with rules that reflect and describe current usage rather than prescribed usage.Information Storage and Retrieval: Organized activities related to the storage, location, search, and retrieval of information.Licensure: The legal authority or formal permission from authorities to carry on certain activities which by law or regulation require such permission. It may be applied to licensure of institutions as well as individuals.Genetic Privacy: The protection of genetic information about an individual, family, or population group, from unauthorized disclosure.Health Policy: Decisions, usually developed by government policymakers, for determining present and future objectives pertaining to the health care system.Trematoda: Class of parasitic flukes consisting of three subclasses, Monogenea, Aspidogastrea, and Digenea. The digenetic trematodes are the only ones found in man. They are endoparasites and require two hosts to complete their life cycle.Trematode Infections: Infections caused by infestation with worms of the class Trematoda.BangladeshMetacercariae: Encysted cercaria which house the intermediate stages of trematode parasites in tissues of an intermediate host.Skin Care: Maintenance of the hygienic state of the skin under optimal conditions of cleanliness and comfort. Effective in skin care are proper washing, bathing, cleansing, and the use of soaps, detergents, oils, etc. In various disease states, therapeutic and protective solutions and ointments are useful. The care of the skin is particularly important in various occupations, in exposure to sunlight, in neonates, and in PRESSURE ULCER.Host-Parasite Interactions: The relationship between an invertebrate and another organism (the host), one of which lives at the expense of the other. Traditionally excluded from definition of parasites are pathogenic BACTERIA; FUNGI; VIRUSES; and PLANTS; though they may live parasitically.Poverty Areas: City, urban, rural, or suburban areas which are characterized by severe economic deprivation and by accompanying physical and social decay.