implant

views updated May 23 2018

im·plant • v. / imˈplant/ [tr.] insert or fix (tissue or an artificial object) in a person's body, esp. by surgery: electrodes had been implanted in his brain. ∎  (implant someone/something with) provide someone or something with (something) by such insertion: rats implanted with amphetamine pellets. ∎  [intr.] (of a fertilized egg) become attached to the wall of the uterus. ∎ fig. establish or fix (an idea) in a person's mind.• n. / ˈimˌplant/ a thing implanted in something else, esp. a piece of tissue, prosthetic device, or other object implanted in the body: a silicone breast implant.

implantation

views updated May 17 2018

implantation of an embryo into the lining of the uterus occurs a week or so after an ovum has been fertilized in one of the Fallopian tubes. The uterine lining has been routinely prepared to receive it in the second half of the menstrual cycle, but the mother's body does not ‘know’ that there is an embryo on the way until it has become embedded and can send hormonal signals via the maternal blood to the ovary whence its ovum came. This chorionic gonadotrophin makes the ovary continue to secrete progesterone, which in turn, via the blood, makes the uterus maintain its welcoming lining, avoiding the catastrophe (for an embryo) of menstruation. The embryo implants itself by passing though the outer cellular layer of the uterine lining, assisted by chemicals which it secretes. At this stage it is more or less spherical and covered with villi (frond-like protrusions); these provide a large surface area for exchange of gases, nutrients, water and waste with the maternal blood.

Stuart Judge


See pregnancy.

implant

views updated May 14 2018

implant (im-plahnt) n. a drug (such as a subcutaneous hormone implant), a prosthesis (such as an artificial hip), or a radioactive source (such as radium needles) that is put into the body. breast i. a prosthesis inserted subcutaneously to replace breast tissue that has been removed surgically during a simple mastectomy in the treatment of breast cancer or to augment existing breast tissue. The type of implant in current use is a silicone sac filled with silicone gel. dental i. a rigid structure that is embedded in the jawbone or under its periosteum to provide support for replacement teeth on a denture or a bridge. heart i. see artificial heart. intraocular lens i. a plastic lens placed inside the eye after cataract surgery. osseointegrated i. an implant that can be introduced into living bone without producing a foreign-body reaction (see osseointegration). See also cochlear implant.

implant

views updated May 18 2018

implant Anything deliberately embedded in the body, other than an organ or tissue from another body (transplant). An implant may be a drug in ‘depot’ form, to provide gradual absorption over an extended period; or a man-made replacement for damaged tissue such as heart valves or major arteries; or a permanent electrical device such as a pacemaker for the heart or a stimulator for emptying the bladder. The computer chip age promises far-reaching developments in this last area. Artificial joints and screws and plates for fixing fractures are also implants, though not usually given that name.

Stuart Judge

implantation

views updated May 21 2018

implantation (im-plahn-tay-shŏn) n.
1. (nidation) the attachment of the early embryo to the lining of the uterus, which occurs six to eight days after ovulation.

2. the placing of a substance (e.g. a drug) or an object (e.g. an artificial pacemaker) within a tissue.

3. the surgical replacement of damaged tissue with healthy tissue (see transplantation).

implantation

views updated May 23 2018

implantation (nidation) (in embryology) The embedding of a fertilized mammalian egg into the wall of the uterus (womb) where it will continue its development. After fertilization in the fallopian tube the egg passes into the womb in the form of a ball of cells (blastocyst). Its outer cells destroy cells of the uterine wall, forming a cavity into which the blastocyst sinks.

implant

views updated Jun 11 2018

implant vb. XVI. — F. implanter or late L.; see IM-1, PLANT.

implant

views updated Jun 08 2018

implant Any substance, device, or tissue that is inserted into the body. For example, drug implants and heart pacemakers are typically inserted under the skin.