|
Chemosterilant
A chemosterilant is a chemical compound that causes reproductive sterility in an organism. Chemosterilants are particularly useful in controlling the population of species that are known to cause disease, such as insects, or species that are, in general, economically damaging. The sterility induced by chemosterilants can have temporary or permanent effects. Chemosterilants can be used to target one or both sexes, and it prevents the organism from advancing to be sexually functional. They may be used to control pest populations by sterilizing males. The need for chemosterilants is a direct consequence of the limitations of insecticides. Insecticides are most effective in regions in which there is high vector density in conjunction with endemic transmission, and this may not always be the case. Additionally, the insects themselves will develop a resistance to the insecticide either on the target protein level or through avoidance of the insecticide in what is called a behavioral res ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zinc Gluconate
Zinc gluconate is the zinc salt of gluconic acid. It is an ionic compound consisting of two anions of gluconate for each zinc(II) cation. Zinc gluconate is a popular form for the delivery of zinc as a dietary supplement providing 14.35% elemental zinc by weight. Gluconic acid is found naturally, and is industrially made by the fermentation of glucose, typically by ''Aspergillus niger'', but also by other fungi, e.g. ''Penicillium'', or by bacteria, e.g. ''Acetobacter'', ''Pseudomonas'' and '' Gluconobacter''. In its pure form, it is a white to off-white powder. It can also be made by electrolytic oxidation, although this is a more expensive process. The advantages are a lower microbiological profile, and a more complete reaction, yielding a product with a longer shelf life. Zinc gluconate and the common cold Zinc gluconate has been used in lozenges for treating the common cold. However, controlled trials with lozenges which include zinc acetate have found it has the greates ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zinc Gluconate
Zinc gluconate is the zinc salt of gluconic acid. It is an ionic compound consisting of two anions of gluconate for each zinc(II) cation. Zinc gluconate is a popular form for the delivery of zinc as a dietary supplement providing 14.35% elemental zinc by weight. Gluconic acid is found naturally, and is industrially made by the fermentation of glucose, typically by ''Aspergillus niger'', but also by other fungi, e.g. ''Penicillium'', or by bacteria, e.g. ''Acetobacter'', ''Pseudomonas'' and '' Gluconobacter''. In its pure form, it is a white to off-white powder. It can also be made by electrolytic oxidation, although this is a more expensive process. The advantages are a lower microbiological profile, and a more complete reaction, yielding a product with a longer shelf life. Zinc gluconate and the common cold Zinc gluconate has been used in lozenges for treating the common cold. However, controlled trials with lozenges which include zinc acetate have found it has the greates ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Compound
A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) containing atoms from more than one chemical element held together by chemical bonds. A molecule consisting of atoms of only one element is therefore not a compound. A compound can be transformed into a different substance by a chemical reaction, which may involve interactions with other substances. In this process, bonds between atoms may be broken and/or new bonds formed. There are four major types of compounds, distinguished by how the constituent atoms are bonded together. Molecular compounds are held together by covalent bonds; ionic compounds are held together by ionic bonds; intermetallic compounds are held together by metallic bonds; coordination complexes are held together by coordinate covalent bonds. Non-stoichiometric compounds form a disputed marginal case. A chemical formula specifies the number of atoms of each element in a compound molecule, using ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Azoospermia
Azoospermia is the medical condition of a man whose semen contains no sperm. It is associated with male infertility, but many forms are amenable to medical treatment. In humans, azoospermia affects about 1% of the male population and may be seen in up to 20% of male infertility situations in Canada. In a non-pathological context, azoospermia is also the intended result of a successful vasectomy. Classification Azoospermia can be classified into three major types as listed. Many conditions listed may also cause various degrees of oligospermia rather than azoospermia. Pretesticular and testicular azoospermia are known as non-obstructive azoospermia, whereas post-testicular azoospermia is considered obstructive. Pretesticular Pretesticular azoospermia is characterized by inadequate stimulation of otherwise normal testicles and genital tract. Typically, follicle-stimulating hormone (FSH) levels are low (hypogonadotropic) commensurate with inadequate stimulation of the testes to prod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromosomes
A chromosome is a long DNA molecule with part or all of the genetic material of an organism. In most chromosomes the very long thin DNA fibers are coated with packaging proteins; in eukaryotic cells the most important of these proteins are the histones. These proteins, aided by chaperone proteins, bind to and condense the DNA molecule to maintain its integrity. These chromosomes display a complex three-dimensional structure, which plays a significant role in transcriptional regulation. Chromosomes are normally visible under a light microscope only during the metaphase of cell division (where all chromosomes are aligned in the center of the cell in their condensed form). Before this happens, each chromosome is duplicated ( S phase), and both copies are joined by a centromere, resulting either in an X-shaped structure (pictured above), if the centromere is located equatorially, or a two-arm structure, if the centromere is located distally. The joined copies are now c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alkylating Agents
Alkylation is the transfer of an alkyl group from one molecule to another. The alkyl group may be transferred as an alkyl carbocation, a free radical, a carbanion, or a carbene (or their equivalents). Alkylating agents are reagents for effecting alkylation. Alkyl groups can also be removed in a process known as dealkylation. Alkylating agents are often classified according to their nucleophilic or electrophilic character. In oil refining contexts, alkylation refers to a particular alkylation of isobutane with olefins. For upgrading of petroleum, alkylation produces a premium blending stock for gasoline. In medicine, alkylation of DNA is used in chemotherapy to damage the DNA of cancer cells. Alkylation is accomplished with the class of drugs called alkylating antineoplastic agents. Nucleophilic alkylating agents Nucleophilic alkylating agents deliver the equivalent of an alkyl anion (carbanion). The formal "alkyl anion" attacks an electrophile, forming a new covalent bond b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metabolite
In biochemistry, a metabolite is an intermediate or end product of metabolism. The term is usually used for small molecules. Metabolites have various functions, including fuel, structure, signaling, stimulatory and inhibitory effects on enzymes, catalytic activity of their own (usually as a cofactor to an enzyme), defense, and interactions with other organisms (e.g. pigments, odorants, and pheromones). A primary metabolite is directly involved in normal "growth", development, and reproduction. Ethylene exemplifies a primary metabolite produced large-scale by industrial microbiology. A secondary metabolite is not directly involved in those processes, but usually has an important ecological function. Examples include antibiotics and pigments such as resins and terpenes etc. Some antibiotics use primary metabolites as precursors, such as actinomycin, which is created from the primary metabolite tryptophan. Some sugars are metabolites, such as fructose or glucose, which a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antimetabolites
An antimetabolite is a chemical that inhibits the use of a metabolite, which is another chemical that is part of normal metabolism. Such substances are often similar in structure to the metabolite that they interfere with, such as the antifolates that interfere with the use of folic acid; thus, competitive inhibition can occur, and the presence of antimetabolites can have toxic effects on cells, such as halting cell growth and cell division, so these compounds are used as chemotherapy for cancer. Function Cancer treatment Antimetabolites can be used in cancer treatment, as they interfere with DNA production and therefore cell division and tumor growth. Because cancer cells spend more time dividing than other cells, inhibiting cell division harms tumor cells more than other cells. Antimetabolite drugs are commonly used to treat leukemia, cancers of the breast, ovary, and the gastrointestinal tract, as well as other types of cancers. In the Anatomical Therapeutic Chemical Classi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ornitrol
Azacosterol (), or azacosterol hydrochloride () (brand name Ornitrol), also known as 20,25-diazacholesterol, is a cholesterol-lowering drug (hypocholesteremic), which was marketed previously, but has since been discontinued. It is also an avian chemosterilant used to control pest pigeon populations via inducing sterility. The drug is a sterol and derivative of cholesterol in which two carbon atoms have been replaced with nitrogen atoms. Azacosterol acts as an inhibitor of 24-dehydrocholesterol reductase (24-DHCR), preventing the formation of cholesterol from desmosterol. Although it primarily acts to inhibit 24-DHCR, the drug also inhibits other steps in cholesterol biosynthesis. The antifertility effects of the drug in birds are mediated by inhibition of steroid hormone production, steroid hormones being synthesized from cholesterol. Due to prevention of the metabolism of desmosterol, the drug causes it to accumulate, in turn producing side effects such as hyperkeratosis, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dog Aggression
Dog aggression expressed by dogs is considered to be normal behaviour and various types of aggression are influenced by a dog's environment and genetic predisposition. Dogs commonly display possessive aggression when defending resources or themselves. Canine aggression may be influenced by a dog's age, sex, health and reproductive status. Canine aggression is one of the most serious behavior problems in animal behavioral medical science. Aggression in canines is particularly important because a dog's sharp teeth can result in serious injuries, or even fatalities in the young or frail. The determinants for each type of aggression are different, but there are specific factors that are common to canine aggression. The types of aggression include dominance aggression, defensive aggression, predatory aggression and maternal aggression. Aggression in canines may be a self-defense response to a person or animal entering a dog's space, which may be ritualized aggression, not actual ag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Doxorubicin
Doxorubicin, sold under the brand name Adriamycin among others, is a chemotherapy medication used to treat cancer. This includes breast cancer, bladder cancer, Kaposi's sarcoma, lymphoma, and acute lymphocytic leukemia. It is often used together with other chemotherapy agents. Doxorubicin is given by injection into a vein. Common side effects include hair loss, bone marrow suppression, vomiting, rash, and inflammation of the mouth. Other serious side effects may include allergic reactions such as anaphylaxis, heart damage, tissue damage at the site of injection, radiation recall, and treatment-related leukemia. People often experience red discoloration of the urine for a few days. Doxorubicin is in the anthracycline and antitumor antibiotic family of medications. It works in part by interfering with the function of DNA. Doxorubicin was approved for medical use in the United States in 1974. It is on the World Health Organization's List of Essential Medicines. Versi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
