Pressure contractions

Raise of blood pressure, contraction of smooth muscles, glycogen breakdown in liver, lipid breakdown in adipose tissue... 

The prostaglandins are a group of modified C20 fatty acids first isolated from human semen and initially assumed to be secreted by the prostate gland. They are now known to occur widely in animal tissues, but only in tiny amounts, and they have been found to exert a wide variety of pharmacological effects on humans and animals. They are active at very low, hormone-like concentrations and can regulate blood pressure, contractions of smooth... 

Neurotensin 11, which was isolated from bovine small intestine by Carraway and Leeman 29) in 1973, causes, in addition to the typical plasma kinin effects (lowering of the blood pressure, contracting action on the intestine and uterus), an increase in the LH and FSH secretion without influencing the release of somatotropin or thyrotropin. 

PROSTAGLANDINS A group of potent hormone-like substances that are produced in various tissues of the hody. Prostaglandins help with a wide range of physiological functions, such as control of hlood pressure, contraction of smooth muscles, and modulation of inflammation. 

The vasopressor effect of HORD is not centrally induced but by its stimulatoiy action on the heart muscle [45]. In isolated vas deferens of guinea pig, relative maximal response of HORD ethiodide was found to be higher (0.22) than tyramine (0.09) as compared to norepinephrine (1.00), which served as the reference [46]. HORD isolated from Phyllophora nervosa increased blood pressure, contracted nictating membrane when injected by i.v. route to cats. This epinephrine-like effect was less potent but more durable than epinephrine [5]. 

At present, the term kinin is a generic name for polypeptides characterized by the following biological effects lowering of blood pressure, contraction of most smooth-muscle preparations, increase of capillary permeability, pain production and bronchoconstiiction in the guinea-pig. The reader is reminded that the nomenclature of this group of substances and of the enzymes which liberate them, as well as the enzymes which inactivate them, is not uniforuL In this chapter, the recommendations of the Committee on Nomenclature for Hypotensive Peptides have been followed... 

Acts to constrict small arteries, thereby increasing blood pressure and to contract smooth muscle. Used in cases of peripheral vasomotor collapse. 

In addition, the separator temperature and pressure of the surface facilities are typically outside the two-phase envelope, so that no liquids form during separation. This makes the prediction of the produced fluids during development very simple, and gas sales contracts can be agreed with the confidence that the fluid composition will remain constant during field life in the case of a dry gas. 

The most important use of the real gas law is to calculate the volume which a subsurface quantity of gas will occupy at surface conditions, since when gas sales contracts are negotiated and gas is subsequently sold it is referred to in volumes at standard conditions of temperature (Tsc) and pressure (Psc). 

The previous equation is only valid as long as there is no compositional change of the gas between the subsurface and the surface. The value of E is typically in the order of 200, in other words the gas expands by a factor of around 200 from subsurface to surface conditions. The actual value of course depends upon both the gas composition and the reservoir temperature and pressure. Standard conditions of temperature and pressure are commonly defined as 60°F (298K) and one atmosphere (14.7 psia or 101.3 kPa), but may vary from location to location, and between gas sales contracts. 

A comfortable margin is maintained between the flowing tubing head pressure (downstream of compression) and the minimum pressure required for export, since the penalties for not meeting contract quantities can be severe. The decision not to install a fourth stage of compression in the above example is dictated by economics. During the final part of the pressure decline above, the field production is of course also declining. 

Physiological responses to prostaglandins encompass a variety of effects Some prostaglandins relax bronchial muscle others contract it Some stimulate uterine con tractions and have been used to induce therapeutic abortions PGEj dilates blood vessels and lowers blood pressure it inhibits the aggregation of platelets and offers promise as a drug to reduce the formation of blood clots... 

Pressure Drop from Are Cha.nge, Pressure drop from area change occurs as a result of energy dissipation associated with eddies formed when a flow area is suddenly expanded or contracted. It is expressed in the following form ... 

W. T. Ziegler, G. N. Brown, and J. D. Garber, Calculation of the Hapor Pressure and Heats ofHapori ation and Sublimation ofdquids and Solids Pelow One Htmosphere Pressure. IX. Neon, Tech. Report No. 1, Contract No. CST-7973, U.S. National Bureau of Standards, Boulder, Colo., 1970. 

The posterior lobe of the pituitary, ie, the neurohypophysis, is under direct nervous control (1), unlike most other endocrine organs. The hormones stored in this gland are formed in hypothalamic nerve cells but pass through nerve stalks into the posterior pituitary. As early as 1895 it was found that pituitrin [50-57-7] an extract of the posterior lobe, raises blood pressure when injected (2), and that Pitocin [50-56-6] (Parke-Davis) causes contractions of smooth muscle, especially in the utems (3). Isolation of the active materials involved in these extracts is the result of work from several laboratories. Several highly active posterior pituitary extracts have been discovered (4), and it has been deterrnined that their biological activities result from peptide hormones, ie, low molecular weight substances not covalendy linked to proteins (qv) (5). 

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