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Sperms

C22H34O2. A straight-chain fatty acid with 5 double bonds. A major component of fish oils and the oils of marine animals, clupeine Protamine class protein found in the sperm and testicles of the herring. On hydrolysis it gives about 90% of argenine. [Pg.102]

Ectocarpene is a volatile sperm cell attracting matenal released by the eggs of the seaweed Ectocarpus siliculosus Its constitution is... [Pg.322]

Multifidene is a sperm cell attracting substance released by the female of a species of brown algae Cutlena rnultifida) The constitution of multifidene is... [Pg.322]

Spermaceti is a wax obtained from the sperm whale It contains among other materials an ester known as cetyl palmitate which is used as an emollient in a number of soaps and cosmetics The systematic name for cetyl palmi tate IS hexadecyl hexadecanoate Write a structural formula for this substance... [Pg.1079]

Oleometer. A hydrometer for determining the density of vegetable and sperm oils with a scale from 50° to 0° corresponding to specific gravities from 0.870 to 0.970. See also Fatty Oil Hydrometer above. [Pg.142]

Fats and oils are one of the oldest classes of chemical compounds used by humans. Animal fats were prized for edibiUty, candles, lamp oils, and conversion to soap. Fats and oils are composed primarily of triglycerides (1), esters of glycerol and fatty acids. However, some oils such as sperm whale (1), jojoba (2), and orange roughy (3) are largely composed of wax esters (2). Waxes (qv) are esters of fatty acids with long-chain aUphatic alcohols, sterols, tocopherols, or similar materials. [Pg.122]

With the beginning of the industrial revolution around 1800, oil became increasingly important for lubrication and better illumination. Expensive vegetable oils were replaced by sperm whale oil [8002-24-2], which soon became scarce and its price skyrocketed. In 1850 lubrication oil was extracted from coal and oil shale (qv) in England, and ultimately about 130 plants in Great Britain and 64 plants in Pennsylvania, West Virginia, and Kentucky employed this process. [Pg.364]

Lead is known to cause reproductive and developmental toxicity. Decreased sperm counts and abnormal sperm development have been reported in male workers heavily exposed to lead. Increased incidences of spontaneous abortion have been reported in female lead workers as well as in the wives of male lead workers (13). Lead crosses the placenta and has been found to cause irreversible neurologic impairment to the fetus at maternal blood levels as... [Pg.78]

Fats and Oils. Fats and oils (6) are traditionally sulfated using concentrated sulfuric acid. These are produced by the sulfation of hydroxyl groups and/or double bonds on the fatty acid portion of the triglyceride. Reactions across a double bond are very fast, whereas sulfation of the hydroxyl group is much slower. Yet 12-hydroxyoleic acid sulfates almost exclusively at the hydroxyl group. The product is generally a complex mixture of sulfated di-and monoglycerides, and even free fatty acids. Other feeds are castor oil, fish oil, tallow, and sperm oil. [Pg.84]

Spermaceti. Spermaceti [8002-23-1] is derived from the head oil of the sperm whale. Owing to the present status of the sperm whale as an endangered species, however, the material is no longer an item of commerce and has been replaced by other natural and synthetic waxes. [Pg.314]

Jojoba is a desert crop that gives a small bean containing about 50% of a wax, a fatty acid ester with a fatty alcohol. The only other large source of such a wax is sperm whale oil, traditionally used in fine lubricants (see Lubrication and lubricants). Because the sperm whale is an endangered species, relatively Httle sperm whale oil is available and there is a large market for a substitute. Jojoba oil has been found to be usable for most of these appHcations. The jojoba oil is obtained by simply pressing the nut followed by conventional refining. Some jojoba oil is used in cosmetics (qv). [Pg.448]

In the last several decades, physical properties of vaginal contraceptive formulations have been improved to deUver spermicide more effectively and enhance consumer compliance. The formulation that deUvers the spermicide can affect the efficacy of vaginal contraceptives (86,87). Formulations currentiy available include jeUies, creams, suppositories, aerosol foams, and foaming tablets. Each consists of a relative inert base material that serves as a carrier for the chemically active spermicide and blocks to some extent the passage of sperm. [Pg.121]

After insertion of an lUD, polymorphonuclear leukocytes and macrophages accumulate in the uterine cavity. These cells appear to phagocytize sperm and Hberate a blastotoxic toxin (92,93). Intrauterine devices also may create a hostile environment, perhaps because antibodies are produced that interfere with implantation of the fertilized ovum (93). [Pg.121]

Diaphragms, shallow mbber cups with a flexible metal rim which are placed in the vagina and cover the cervix, are both a mechanical barrier to sperm and a receptable for spermicidal agent. The mechanism of action is beheved to be a combination of spermicidal and mechanical barrier actions. To be effective, the diaphragm must fit correctly, be inserted properly, and remain in place sufficiently long for the spermicide to act (99). [Pg.122]

The primary difficulty with periodic abstinence is the month-to-month variation in the time of ovulation. Whereas the ovum can only be fertilized during the first 12 to 24 hours after its release from the ovary, sperm remain viable longer in the female reproductive tract, able to fertilize an ovum for 5—7 days and perhaps longer. Thus, intercourse several days prior to ovulation can result in pregnancy. [Pg.122]

PH-20, a guinea pig sperm protein of 64 kD, is present on both the plasma membrane and inner acrosomal membrane of sperm. It is essential for adhesion of sperm to the zona peUucida, the initial step in the fertilization process. Active immunization with PH-20 causes infertility in both male and female guinea pigs for a period ranging from 6 to 15 months (120). [Pg.123]

Another interesting sperm specific antigen is lactic dehydrogenase-x (LDH-x or LDHC, an isoenzyme of LDH confined to male germ ceUs. [Pg.123]

Organic molecules thus far identified, such as those fisted above, appear either to have irreversible antifertifity effects, to be inherently toxic, or to affect libido. It has been demonstrated that sperm count could be depressed in men injected with large doses of androgens. However, questions about the potential utility of androgens as male antifertifity agents are stiU debated. [Pg.123]

A study of sperm counts conducted worldwide suggested that an annual fall of 0.8% had occurred between 1938 and 1990. Since then, falling sperm count and quality have been reported in a number of countriesand a recent study of... [Pg.5]


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A Push-Pull Model for Nematode Sperm Amoeboid Motility

Abalone sperm

Acrosome reaction mammalian sperm

Amino acid composition basic nuclear protein from bull sperm thynnine

Amphibians sperm binding

Analysis of the sperm tail movement

Ascaris sperm

Assays for Sperm Chemotaxis

Basic proteins from sperm

Bovine sperm capacitation

Capacitation mammalian sperm

Computer assisted sperm analysis

Computer assisted sperm analysis CASA)

Cryopreservation sperm

Endo-sperm

Epididymal sperm density

Fertilization sperm

Fish sperm

Flagella, flagellum sperm

Flow cytometry sperm

Hamster sperm

Intracytoplasmic sperm injection

Intracytoplasmic sperm injection ICSI)

Ivory sperm whale

Major sperm protein

Major sperm protein Ascaris

Mammalian sperm

Mouse sperm

Mouse sperm capacitation

Mouse sperm tyrosine phosphorylation

Nematode Sperm is Coupled to Assembly and Disassembly of the Cytoskeleton

Partial Characterization of a Basic Protein from Bull Sperm Heads

Protein sperm whale myoglobin

Rat sperm

Recent studies of sperm chemotaxis in mammals

Ruthenated sperm whale myoglobin

SPERM method

Salmon Sperm and Calf Thymus DNA

Salmon sperm

Salmon sperm DNA

Salmon sperm, deoxyribonucleic acid

Sea urchin sperm

Sea urchin sperm acrosome reaction

Sea urchin sperm bindin

Separation and Purification of Protamines from Sperm Heads or Nucleoprotamine

Species Specificity of Sperm Chemotaxis

Sperm DNA

Sperm Heads

Sperm RNAs

Sperm accumulation in a descending chemoattractant gradient

Sperm agglutination

Sperm antibodies

Sperm assembly

Sperm attractant

Sperm binding

Sperm buffers

Sperm capacitation

Sperm cell membrane

Sperm cell production

Sperm cell-free systems

Sperm cells

Sperm chemoattractants

Sperm chemotaxis

Sperm chemotaxis accumulation assays

Sperm chemotaxis assays

Sperm chemotaxis in mammals

Sperm chromatin structure assay

Sperm collection

Sperm competition

Sperm continuous production

Sperm count/quality

Sperm counts

Sperm cryopreservation methods and adaptation to hatcheries

Sperm cryopreservation reviews

Sperm cryopreservation species

Sperm dilution buffer

Sperm duct

Sperm effects

Sperm endocannabinoid signaling

Sperm fertilizing potential

Sperm function

Sperm functionality

Sperm hatcheries

Sperm heads, composition

Sperm hyperactivation

Sperm interaction

Sperm locomotion

Sperm maturation

Sperm membrane potential

Sperm migration

Sperm mitochondria

Sperm motility

Sperm number

Sperm oil

Sperm overview

Sperm packaging

Sperm penetration

Sperm penetration, acrosin

Sperm precedence

Sperm production

Sperm production alterations

Sperm quality

Sperm receptors

Sperm reservoir

Sperm retention

Sperm selection

Sperm spermatozoa

Sperm storage

Sperm supply

Sperm transfer

Sperm tube growth

Sperm whale

Sperm whale apoMb

Sperm whale extract

Sperm whale metMb

Sperm whale myoglobin

Sperm whale myoglobin, schematic

Sperm whale tooth

Sperm whale, ambergris from

Sperm, DNA damage

Sperm, bovine

Sperm, flagella

Sperm, increased motility

Sperm-Egg Coat Binding

Sperm-activating peptide (speract

Sperm-egg

Sperm-mediated gene transfer

Synthesis of a Human Sperm CD52 Antigen GPI Anchor

Techniques for measuring sperm motility

Types of sperm motility in different species

Types of sperm motility within the female genital tract

Xenopus sperm chromatin preparation

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