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The prostate is an exocrine gland Zaumzeug Prostata-Download the male reproductive system in most mammals. Anatomically, the prostate can be subdivided in two ways: by zone Zaumzeug Prostata-Download by lobe. It does not have a capsule ; rather an integral fibromuscular band surrounds Zaumzeug Prostata-Download.
The prostate also contains some smooth muscles that also Zaumzeug Prostata-Download expel semen during ejaculation. The function of the prostate is to secrete a fluid which contributes to the volume of the semen.
The prostatic fluid is expelled in the first part of ejaculate, together with most of the sperm. In comparison with the few spermatozoa expelled together with Zaumzeug Prostata-Download seminal vesicular fluid, those in prostatic fluid have better motilitylonger survival, and better protection of genetic material. Disorders of the prostate include enlargement, inflammationZaumzeug Prostata-Download, and cancer. The prostate is a gland found in males.
In adults, it is about the size of a walnut. Within it sits the urethra coming from the bladder is called the prostatic urethra and merges with the two ejaculatory ducts. A study stated that prostate volume among patients with negative biopsy is related significantly with weight and height body mass indexso it is necessary to control for weight.
One can sub-divide the prostate in two ways: by zone or by lobe. The "lobe" classification is more often used in anatomy. The prostate is incompletely divided into five lobes:. The prostate has been described as consisting of three or four zones. The tissue of the prostate consists of Zaumzeug Prostata-Download and stroma.
The stroma of the Zaumzeug Prostata-Download is made up Zaumzeug Prostata-Download fibrous tissue and Zaumzeug Prostata-Download muscle. Over time, thickened secretions called corpora amylacea accumulate in the gland. Three histological types of cells are present in the prostate gland: glandular cells, myoepithelial cells, and subepithelial interstitial cells. The prostatic part of the urethra develops from the middle, pelvic, part of the urogenital sinusof endodermal origin.
Condensation of mesenchymeurethraand Wolffian ducts gives rise to the adult prostate gland, a composite organ made up of several tightly fused glandular and non-glandular components. To function properly, the prostate needs male hormones androgenswhich are responsible for male sex characteristics.
The main male hormone is testosteronewhich is Zaumzeug Prostata-Download mainly by the testicles. It is dihydrotestosterone DHTa metabolite of testosterone, that predominantly regulates the prostate.
Zaumzeug Prostata-Download prostate gland enlarges over time, until the fourth decade of life. During male seminal emission, sperm is transmitted from the vas deferens into the male urethra via the ejaculatory ducts, which lie within the prostate gland. Stimulation sends nerve signals via the internal pudendal nerves to the upper lumbar spine; the nerve signals causing contraction act via the hypogastric nerves.
It is possible for some men to achieve orgasm solely through stimulation of the prostate gland, such as prostate massage or anal intercourse. Prostatitis is inflammation Zaumzeug Prostata-Download the prostate gland. It can be caused by infection Zaumzeug Prostata-Download bacteria, or other noninfective causes. Inflammation of the prostate can cause painful urination or ejaculation, Zaumzeug Prostata-Download pain, difficulty passing urine, or constitutional symptoms.
A culprit bacteria may Zaumzeug Prostata-Download in a urine culture. Acute prostatitis and chronic bacterial prostatitis are treated with antibiotics. More recently, a combination of trigger point and psychological therapy has proved effective for category III prostatitis as well. Benign prostatic hyperplasia refers to a non-malignant enlargement hyperplasia of the prostate that is very common in older men.
Symptoms include needing to urinate often frequencyor Zaumzeug Prostata-Download a while to get started hesitancy. If Zaumzeug Prostata-Download prostate grows too large, it may constrict the urethra and impede the flow of urine, making urination difficult and painful and, in extreme cases, completely impossible, causing urinary retention.
BPH can be treated with medication, a minimally invasive procedure or, in extreme cases, surgery that removes the prostate. In general, treatment often begins with a alpha antagonist medication such as tamsulosinwhich reduces the tone of the smooth muscle found in the ureter that passes through the prostate, making it easier for urine to pass through.
The surgery most often used in such cases is called Zaumzeug Prostata-Download resection of the prostate in which an instrument is inserted through the urethra to remove prostate tissue that is pressing against the upper part of the urethra and restricting the flow of urine. This results in the removal of mostly transitional zone tissue Zaumzeug Prostata-Download a patient with BPH.
Prostate cancer is one of the most common cancers affecting older men in the UKUS and Northern Europe  and a significant cause of death for Zaumzeug Prostata-Download men in Zaumzeug Prostata-Download countries.
Uncommonly, such cancers may cause weight loss, urinary retention, or other Zaumzeug Prostata-Download due to lesions outside of the prostate, such as back pain. A digital rectal examination and the measurement of a prostate specific antigen PSA level are usually the first investigations done to check for prostate cancer.
PSA values are difficult to interpret, because a high value might be present in a person without cancer, and a low Zaumzeug Prostata-Download can be present in someone with cancer. Prostate cancer that is only present in the prostate is often treated with either surgical removal of the prostate or with radiotherapy or by the insertion of small radioactive particles brachytherapy  Cancer that has spread to other parts of the body is usually treated with hormone therapy, to deprive a tumour of sex hormones androgens that stimulate proliferation.
This is often done through the use of GnRH analogues Zaumzeug Prostata-Download agents that block the receptors that Zaumzeug Prostata-Download act Zaumzeug Prostata-Download, such as bicalutamide Zaumzeug Prostata-Download occasionally, surgical removal of the testes may be done instead. Radiotherapy may also Zaumzeug Prostata-Download used to help with pain associated with bony lesions. Sometimes, the decision may be made not to treat prostate cancer.
If a cancer is small and localised, the decision may Zaumzeug Prostata-Download made to monitor for cancer activity Zaumzeug Prostata-Download intervals "Active surveillance" and commence treatment. John E. McNeal first proposed the idea of Zaumzeug Prostata-Download in McNeal found that the relatively homogeneous cut surface of an adult prostate in no way resembled "lobes" and thus led to the description of "zones".
The prostate is found as a male accessory gland in all placental mammals excepting edentatesmartensbadgers and otters. The gland is particularly well developed in dogs, foxes and boars, though in other mammals, such as bulls, it can be small and inconspicuous.
They excrete this fluid along with their urine to mark their territory. This mixes with and coagulates semen during copulation to form a mating plug that temporarily prevents further copulation. Prostatic secretions vary among species. They are generally composed of simple sugars and are often slightly alkaline. The prostate gland originates with tissues in the urethral wall.
This means the urethraa compressible tube used for urination, runs through the middle Zaumzeug Prostata-Download the prostate. This Zaumzeug Prostata-Download to an evolutionary design fault for some mammals, including human males. The prostate is prone Zaumzeug Prostata-Download infection and enlargement later in life, constricting the urethra so urinating becomes slow and painful.
Skene's gland is found in Zaumzeug Prostata-Download female humans and rodents. Historically it was thought to be a vestigial organ, but recently it has been discovered that it produces the same protein markers, PSA and PABas the male prostate. Monotremes and marsupial moles lack prostates, instead having simpler cloacal glands that carry their function. A prostate gland also occurs in some invertebrate species, Zaumzeug Prostata-Download as gastropods.
From Wikipedia, the free encyclopedia. This is the latest accepted revisionreviewed on 31 October This Zaumzeug Prostata-Download is about the male prostate gland. For the equivalent female prostate gland, see Skene's gland.
For the "prostrate" body position, see Prostration. For the journal, see The Prostate. Zaumzeug Prostata-Download article: Prostate massage. Main article: Prostatitis.
A digital rectal examinations may be performed to investigate how large a prostate is, or if a prostate is tender which may indicate inflammation. A diagram of prostate cancer pressing on the urethra, which can cause symptoms. Micrograph showing an Zaumzeug Prostata-Download prostate gland, the histologic correlate of prostatitis.
A normal non-inflamed prostatic gland is seen on the left of the image. Micrograph showing normal prostatic glands and glands of prostate cancer prostatic adenocarcinoma — right upper aspect of image. HPS stain. Prostate biopsy. Main article: Benign prostatic hyperplasia. Main article: Prostate cancer. The Vertebrate Body. The Histochemical Zaumzeug Prostata-Download. Online Etymology Dictionary. Retrieved Annals of the Royal College of Surgeons of England. Henry Am Zaumzeug Prostata-Download Physiol.
Wheater's Zaumzeug Prostata-Download histology: a text and colour atlas 6th ed. Philadephia: Elsevier. Prostate Cancer and Prostatic Diseases. Clinical Anatomy. Urology Match. The Journal of Urology. Archived from the original on