|
Parasitosis
A parasitic disease, also known as parasitosis, is an infectious disease caused by parasites. Parasites are organisms which derive sustenance from its host while causing it harm. The study of parasites and parasitic diseases is known as parasitology. Medical parasitology is concerned with three major groups of parasites: parasitic protozoa, helminths, and parasitic arthropods. Parasitic diseases are thus considered those diseases that are caused by pathogens belonging taxonomically to either the animal kingdom, or the protozoan kingdom. Terminology Although organisms such as bacteria function as parasites, the usage of the term "parasitic disease" is usually more restricted. The three main types of organisms causing these conditions are protozoa (causing protozoan infection), helminths ( helminthiasis), and ectoparasites. Protozoa and helminths are usually endoparasites (usually living inside the body of the host), while ectoparasites usually live on the surface of the host ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electron Micrograph
A micrograph is an image, captured photographically or digitally, taken through a microscope or similar device to show a magnify, magnified image of an object. This is opposed to a macrograph or photomacrograph, an image which is also taken on a microscope but is only slightly magnified, usually less than 10 times. Micrography is the practice or art of using microscopes to make photographs. A photographic micrograph is a photomicrograph, and one taken with an electron microscope is an electron micrograph. A micrograph contains extensive details of microstructure. A wealth of information can be obtained from a simple micrograph like behavior of the material under different conditions, the phases found in the system, failure analysis, grain size estimation, elemental analysis and so on. Micrographs are widely used in all fields of microscopy. Types Photomicrograph A light micrograph or photomicrograph is a micrograph prepared using an optical microscope, a process referred to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helminths
Parasitic worms, also known as helminths, are a polyphyletic group of large macroparasites; adults can generally be seen with the naked eye. Many are intestinal worms that are soil-transmitted and infect the gastrointestinal tract. Other parasitic worms such as schistosomes reside in blood vessels. Some parasitic worms, including leeches and monogeneans, are ectoparasites thus, they are not classified as helminths, which are endoparasites. Parasitic worms live in and feed in living hosts. They receive nourishment and protection while disrupting their hosts' ability to absorb nutrients. This can cause weakness and disease in the host, and poses a global health and economic problem. Parasitic worms cannot reproduce entirely within their host's body; they have a life cycle that includes some stages that need to take place outside of the host. Helminths are able to survive in their mammalian hosts for many years due to their ability to manipulate the host's immune respons ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Animal Sexual Behaviour
Animal sexual behaviour takes many different forms, including within the same species. Common mating or Reproduction, reproductively motivated systems include Monogamous pairing in animals, monogamy, Polygyny in animals, polygyny, Polyandry in nature, polyandry, Animal sexual behaviour#Polygamy, polygamy and Promiscuity#Other animals, promiscuity. Other sexual behaviour may be reproductively motivated (e.g. Sexual coercion among animals, sex apparently due to duress or coercion and situational sexual behaviour) or Non-reproductive sexual behavior in animals, non-reproductively motivated (e.g. Homosexual behavior in animals, homosexual sexual behaviour, bisexuality, bisexual sexual behaviour, cross-species sex, Paraphilia, sexual arousal from objects or places, Necrophilia in animals, sex with dead animals, etc.). When animal sexual behaviour is reproductively motivated, it is often termed ''mating'' or ''Copulation (zoology), copulation''; for most non-human mammals, mating and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bug Bites
Many species of arthropods (insects, arachnids, millipedes and centipedes) can bite or sting human beings. These bites and stings generally occur as a defense mechanism or during normal arthropod feeding. While most cases cause self-limited irritation, medically relevant complications include envenomation, allergic reactions, and transmission of vector-borne diseases. Signs and symptoms Most arthropod bites and stings cause self-limited redness, itchiness and/or pain around the site. Less commonly (around 10% of Hymenoptera sting reactions), a large local reaction occurs when the area of swelling is greater than . Rarely (1-3% of Hymenoptera sting reactions), systemic reactions can affect multiple organs and pose a medical emergency, as in the case of anaphylactic shock. Defensive and predatory bites and stings Many arthropods bite or sting in order to immobilize their prey or deter potential predators as a defense mechanism. Stings containing venom are more likely to be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Water
Water is an inorganic compound with the chemical formula . It is a transparent, tasteless, odorless, and Color of water, nearly colorless chemical substance. It is the main constituent of Earth's hydrosphere and the fluids of all known living organisms (in which it acts as a solvent). It is vital for all known forms of life, despite not providing food energy or organic micronutrients. Its chemical formula, , indicates that each of its molecules contains one oxygen and two hydrogen atoms, connected by covalent bonds. The hydrogen atoms are attached to the oxygen atom at an angle of 104.45°. In liquid form, is also called "water" at standard temperature and pressure. Because Earth's environment is relatively close to water's triple point, water exists on Earth as a solid, a liquid, and a gas. It forms precipitation in the form of rain and aerosols in the form of fog. Clouds consist of suspended droplets of water and ice, its solid state. When finely divided, crystalline ice ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Food
Food is any substance consumed by an organism for Nutrient, nutritional support. Food is usually of plant, animal, or Fungus, fungal origin and contains essential nutrients such as carbohydrates, fats, protein (nutrient), proteins, vitamins, or Mineral (nutrient), minerals. The substance is Ingestion, ingested by an organism and assimilated by the organism's Cell (biology), cells to provide energy, maintain life, or stimulate growth. Different species of animals have different List of feeding behaviours, feeding behaviours that satisfy the needs of their metabolisms and have evolved to fill a specific ecological niche within specific geographical contexts. Omnivore, Omnivorous humans are highly adaptable and have adapted to obtaining food in many different ecosystems. Humans generally use cooking to prepare food for consumption. The majority of the food energy required is supplied by the industrial food industry, which produces food through Intensive farming, intensive agricu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mammals
A mammal () is a vertebrate animal of the class Mammalia (). Mammals are characterised by the presence of milk-producing mammary glands for feeding their young, a broad neocortex region of the brain, fur or hair, and three middle ear bones. These characteristics distinguish them from reptiles and birds, from which their ancestors diverged in the Carboniferous Period over 300 million years ago. Around 6,640 extant species of mammals have been described and divided into 27 orders. The study of mammals is called mammalogy. The largest orders of mammals, by number of species, are the rodents, bats, and eulipotyphlans (including hedgehogs, moles and shrews). The next three are the primates (including humans, monkeys and lemurs), the even-toed ungulates (including pigs, camels, and whales), and the Carnivora (including cats, dogs, and seals). Mammals are the only living members of Synapsida; this clade, together with Sauropsida (reptiles and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paragonimus Westermani
''Paragonimus westermani'' (Japanese lung fluke or oriental lung fluke) is the most common species of lung fluke that infects humans, causing paragonimiasis. Human infections are most common in eastern Asia and in South America. Paragonimiasis may present as a sub-acute to chronic inflammatory disease of the lung. It was discovered by Dutch zoologist Coenraad Kerbert in 1878. Causative agent More than 30 species of trematodes (flukes) of the genus ''Paragonimus'' have been reported to infect animals and humans. Among the more than 10 species reported to infect humans, the most common is ''Paragonimus westermani'', the oriental lung fluke. Morphology In size, shape, and color, ''Paragonimus westermani'' resembles a coffee bean when alive. Adult worms are 7.5 mm to 12 mm long and 4 mm to 6 mm wide. The thickness ranges from 3.5 mm to 5 mm. The skin of the worm ( tegument) is thickly covered with scalelike spines. The oral and ventral suckers are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clonorchis Sinensis
''Clonorchis sinensis'', the Chinese liver fluke, is a liver fluke belonging to the class trematode, Trematoda, phylum Platyhelminthes. It infects fish-eating mammals, including humans. In humans, it infects the common bile duct and gall bladder, feeding on bile. It was discovered by British physician James McConnell at the Medical College Hospital in Calcutta (Kolkata) in 1874. The first description was given by Thomas Spencer Cobbold, who named it ''Distoma sinense''. The fluke passes its lifecycle in three different hosts, namely freshwater snail as first intermediate hosts, freshwater fish as second intermediate host, and mammals as definitive hosts. Endemic to Asia and Russia, ''C. sinensis'' is the most prevalent human fluke in Asia and third-most in the world. It is still actively transmitted in Korea, China, Vietnam, and Russia. Most infections (about 85%) occur in China. The infection, called clonorchiasis, generally appears as jaundice, indigestion, biliary inflammation, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trypanosoma Cruzi
''Trypanosoma cruzi'' is a species of parasitic euglenoids. Among the protozoa, the trypanosomes characteristically bore tissue in another organism and feed on blood (primarily) and also lymph. This behaviour causes disease or the likelihood of disease that varies with the organism: Chagas disease in humans, dourine and surra in horses, and a brucellosis-like disease in cattle. Parasites need a host body and the haematophagous insect triatomine (descriptions "assassin bug", "cone-nose bug", and "kissing bug") is the major vector in accord with a mechanism of infection. The triatomine likes the nests of vertebrate animals for shelter, where it bites and sucks blood for food. Individual triatomines infected with protozoa from other contact with animals transmit trypanosomes when the triatomine deposits its faeces on the host's skin surface while blood feeding. Penetration of the infected faeces is further facilitated by the scratching of the bite area by the human or animal h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trypanosoma Brucei
''Trypanosoma brucei'' is a species of parasitic Kinetoplastida, kinetoplastid belonging to the genus ''Trypanosoma'' that is present in sub-Saharan Africa. Unlike other protozoan parasites that normally infect blood and tissue cells, it is exclusively extracellular and inhabits the blood plasma and body fluids. It causes deadly vector-borne diseases: African trypanosomiasis or sleeping sickness in humans, and animal trypanosomiasis or ''nagana'' in cattle and horses. It is a species complex grouped into three subspecies: ''T. b. brucei'', ''T. b. gambiense'' and ''T. b. rhodesiense''. The first is a parasite of non-human mammals and causes ''nagana'', while the latter two are zoonotic infecting both humans and animals and cause African trypanosomiasis. ''T. brucei'' is transmitted between mammal hosts by an insect Vector (epidemiology), vector belonging to different species of tsetse fly (''Glossina''). Transmission occurs by biting during the insect's blood meal. The parasites ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Animals
Animals are multicellular, eukaryotic organisms in the biological kingdom Animalia (). With few exceptions, animals consume organic material, breathe oxygen, have myocytes and are able to move, can reproduce sexually, and grow from a hollow sphere of cells, the blastula, during embryonic development. Animals form a clade, meaning that they arose from a single common ancestor. Over 1.5 million living animal species have been described, of which around 1.05 million are insects, over 85,000 are molluscs, and around 65,000 are vertebrates. It has been estimated there are as many as 7.77 million animal species on Earth. Animal body lengths range from to . They have complex ecologies and interactions with each other and their environments, forming intricate food webs. The scientific study of animals is known as zoology, and the study of animal behaviour is known as ethology. The animal kingdom is divided into five major clades, namely Porifera, Ctenophora, P ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
