Steroid isolation , depending on context, is the isolation of chemical matter required for chemical structure elucidation, derivitzation or degradation chemistry, biological testing, and other research needs (generally milligrams to grams, but often more  or the isolation of "analytical quantities" of the substance of interest (where the focus is on identifying and quantifying the substance (for example, in biological tissue or fluid). The amount isolated depends on the analytical method, but is generally less than one microgram.  [ page needed ] The methods of isolation to achieve the two scales of product are distinct, but include extraction , precipitation, adsorption , chromatography , and crystallization . In both cases, the isolated substance is purified to chemical homogeneity; combined separation and analytical methods, such as LC-MS , are chosen to be "orthogonal"—achieving their separations based on distinct modes of interaction between substance and isolating matrix—to detect a single species in the pure sample. Structure determination refers to the methods to determine the chemical structure of an isolated pure steroid, using an evolving array of chemical and physical methods which have included NMR and small-molecule crystallography .  :10–19 Methods of analysis overlap both of the above areas, emphasizing analytical methods to determining if a steroid is present in a mixture and determining its quantity. 
This should give you a good understanding of tren and how perfect of a compound it is when you’re choosing which AAS to run. In most cases tren should not be run by itself; tren will shut down your natural testosterone production and you’re best suited to stack tren with some form of testosterone. Also, an important note, Trenbolone is typically not suitable for beginners; Trenbolone as we can see is a very, very potent compound and the side effects in some cases can be brutal for some lifters. That is also another reason why Trenbolone Acetate is best in comparison to other forms of Trenbolone. Because it has the Acetate ester attached to it, making it very fast acting and giving it a very short half-life, if problems arise, the lifter can discontinue Trenbolone Acetate and have it cleared from his system very quickly.
The metabolites of NGMN and EE are eliminated by renal and fecal pathways. Following administration of 14 C-norgestimate, 47% (45 to 49%) and 37% (16 to 49%) of the administered radioactivity was eliminated in the urine and feces, respectively. Unchanged NGM was not detected in the urine. In addition to 17-deacetyl norgestimate, a number of metabolites of NGM have been identified in human urine following administration of radiolabeled NGM. These include 18, 19-Dinor-17-pregn-4-en-20- yn-3-one,17-hydroxy-13-ethyl,(17α)-(-);18,19-Dinor-5β17-pregnan-20-yn,3α,17β-dihydroxy-13- ethyl,(17α), various hydroxylated metabolites and conjugates of these metabolites.