Members of the Eucestoda have no mouth or digestive tract, and instead absorb nutrients through a layer of microtriches over the tegument at the shared body wall surface. In addition to the body wall, several other systems are common to the whole length of the tapeworm, including excretory canals, nerve fibers, and longitudinal muscles. The excretory system is responsible for osmoregulation and consists of blind-ending flame bulbs communicating through a duct system. The nervous system, often referred to as a "ladder system," is a system of longitudinal connectives and transverse ring commissures. Reproduction
The reproductive systems develop progressively along the differentiated proglottids of the strobila region, with each proglottid developing one or two sets of sexual organs that differentiate at different times in a species-specific pattern, usually male-first. Thus, moving in the posterior direction of the continuously maturing proglottid chain, there are proglottids with mature male reproductive organs, then proglottids with mature female reproductive organs, and then proglottids with fertilized eggs in the uterus, a condition commonly referred to as "gravid." Proglottids
An atrium on the lateral margin of each proglottid contains the openings to both the male and female genital ducts. Follicular testes produce sperm, which are carried by a system of ducts to the cirrus, an eversible copulatory organ that usually has a hypodermic system of spines and a holdfast system of hooks. The main specialized female reproductive organs are an ovary that produces eggs and a vitellarium that produces yolk cells.
Goserelin, sold under the brand name Zoladex among others, is a medication which is used to suppress production of the sex hormones (testosterone and estrogen), particularly in the treatment of breast and prostate cancer. It is an injectable gonadotropin releasing hormone agonist (GnRH agonist). Structurally, it is a decapeptide. It is the natural GnRH decapeptide with two substitutions to inhibit rapid degradation. Goserelin stimulates the production of the sex hormones testosterone and estrogen in a non-pulsatile (non-physiological) manner. This causes the disruption of the endogenous hormonal feedback systems, resulting in the down-regulation of testosterone and estrogen production. It was patented in 1976 and approved for medical use in 1987. It is on the World Health Organizations List of Essential Medicines. Medical uses
Goserelin is used to treat hormone-sensitive cancers of the breast (in pre- and peri-menopausal women) and prostate, and some benign gynaecological disorders (endometriosis, uterine fibroids and endometrial thinning). In addition, goserelin is used in assisted reproduction and in the treatment of precocious puberty. It may also be used in the treatment of male-to-female transgender people and is favoured above other anti-androgens in some countries, such as the UK. It is available as a 1-month depot and a long-acting 3-month depot. Goserelin is administered by subcutaneous injection as an implant every 28 days for the duration of treatment. Side effects
Goserelin may cause a temporary increase in bone pain and symptoms of prostatic cancer during the first few weeks of treatment.