Reduction of resistance

Ducts are used to transport the exhaust air and its contaminants to the collection area. An important feature of duct design is reduction of resistance to air flow from friction within the wall, aggravated by unnecessary curves and bends (particularly right-angled bends), as well as junctions with other ducts at sharp angles, collections of dust, and changes in duct diameter. 

The drugs of this class (hydralazine and sodium nitroprusside) lower arterial blood pressure primarily by direct spasmolytic action on smooth musculature of arterioles, which leads to a reduction of resistance of peripheral vessels by causing dilation. Diastolic pressure is usually lowered more than the systolic pressure. 

Analyzing this equation with reference to hydrogen flow in hydride beds, it is possible to note a number of constructive measures which promote reduction of resistance of hydrogen flow P-m-Poud reduction of thickness of a bed of hydride (characteristic size 8Ch), passing hydrogen reduction of pores tortuosity (asjn) and increase in their diameter (dp) increase in porosity of covering s. Presentation of these requirements speaks about necessity of use for porous beds of structures with the open, organized porosity of small relative size (l/dp <100, at 8ch=5 mmdp <50 microns). 

They found that the reduction of resistance to carbenicillin in the presence of EDTA appears to be inversely related to the quantity of /3-lactamase produced by the bacterial strain. 

Any enhancing effect of surfactants on drug absorption appears to be related to increased drug solubilization, modification of mucosal permeability, or reduction of resistance of the unstirred water layer at the GI membrane surface. In general, unionic surfactants have little effect on membrane structure but cationic surfactants have been associated with reversible cell loss and loss of goblet cells. These effects must limit consideration of surfactants as absorption promoters, particularly for long term treatment. 

F. Vasodilators Vasodilator therapy with nitroprusside or nitroglycerin is often used for acute severe congestive failure. The use of these vasodilator drugs is based on the reduction in cardiac size and improved efficiency that can be realized with proper adjustment of venous return and reduction of resistance to ventricular ejection. Vasodilator therapy can be dramatically effective, especially in cases in which increased afterload is a major factor in causing the failure (eg, continuing hypertension in an individual who has just had an infarct). Chronic congestive heart failure sometimes responds favorably to oral vasodilators such as hydralazine or isosorbide dinitrate. 

Polyacrylamide El, with the lowest electrochemical degradation factor of 11.2 in Table 3, experiences the smallest reduction of resistance factor in the presence of univalent and divalent electrolytes, from 55.9 in river water to 49.5 in an 80/20 mixture of river and formation waters. These unusually large resistance factors probably resulted from the hydrodynamic resistance of the long linear polymer chain which is a unique characteristic of its gamma radiation manufacturing process. There appears to be some correspondence between the effect of electrolytes on viscosity and screen factor since polymers C and D1 with the lowest electrochemical degradation exhibit the greatest reduction in screen factor on... 

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