The Active Substance

General types of physiological functions attributed to quaternary ammonium compounds are curare action, muscarinic—nicotinic action, and ganglia blocking action. The active substance of curare is a quaternary that can produce muscular paralysis without affecting the central nervous system or the heart. Muscarinic action is the stimulation of smooth-muscle tissue. Nicotinic action is primary transient stimulation and secondary persistent depression of sympathetic and parasympathetic ganglia. 

The paper presents the experimental and theoretical data regarding the realization and characterization of three liquid-membrane electrodes, which have not been mentioned in the specialized literature so far. The active substances whose solutions in nitrobenzene have constituted the membranes on a graphite rod, are simple complex combinations of the Cu(II) and Ni(II) ions with Schiff base N-[2-thienylmethylidene]-2-aminothiophenol (TNATPh). 

EC Directive including the active substance kxesoxim-methyl in Annex I of 91/414/EEC concerning... 

If the tube T, containing the active substance, be interposed between the two mcols, then both rays OB and OB will he rotated through equal angles, and to re-establish unifoi in... 

The guideline concludes with a note that there is no intention to require further data on established medicinal products which contain a racemic drug unless new evidence emerges concerning the safety or efficacy of one enantiomer. If new claims related to the chiral nature of the active substance are made, then supporting studies on the individual enantiomers will be required. 

A secondary standard is a substance which may be used for standardisations, and whose content of the active substance has been found by comparison against a primary standard. It follows that a secondary standard solution is a solution in which the concentration of dissolved solute has not been determined from the weight of the compound dissolved but by reaction (titration) of a volume of the solution against a measured volume of a primary standard solution. 

Kuwabara, S., and Wassink, E. C. (1966). Purification and properties of the active substance of fungal luminescence. In Johnson, F. H., and Haneda, Y. (eds.), Bioluminescence in Progress, pp. 233-245. Princeton University Press, Princeton, NJ. 

Dronabinol is the only currently available derivative of THC, which is a derivative of the active substance found in marijuana Dronabinol is a second-line antiemetic and is used after treatment with other antiemetics has failed. 

Changes to the active substance(s), such as use of different salts, complexes, isomers, or slightly different biological materials. 

The EU will accept applications without supporting pre-clinical and clinical data, if it can be demonstrated that the active substances have been in well-established medical use in the Community for at least 10 years, with recognised efficacy and an acceptable level of safety. This route would be appropriate for many common over-the-counter (OTC) products. Safety and efficacy is supported by providing copies of published scientific literature as part of the submission that is, the submission relies on safety and efficacy data available in the public domain, as opposed to confidential data from authorised applications that is the cornerstone of generic applications. 

In macromolecular dmg delivery systems, dmgs are attached to polymeric compounds, such as synthetic polymers [60], dendrimers [61], and antibodies [62], in order to enhance the delivery of the active substance to the diseased tissue and to reduce the toxicity to healthy tissue. The use of macromolecular delivery systems provides several advantages extension of the half-life of the dmg, the ability to introduce targeting moieties into the carrier, the possibility of triggered dmg release, and the aforementioned reduced cytotoxicity. 

Homogenates of MetruUum senile, possibly the world s most common large sea anemone, yield extracts that are powerfully hemolytic for washed mammalian erythrocytes (22). The active substance, metridiolysin, is a protein of molecular weight approximately 80,000. In contrast to the sphingomyelin-inhibitable toxins, metridiolysin is an acidic protein having a pi of about 5. It is thermolabile and is inactivat by proteolytic enzymes. The optimal pH for hemolysis is between 5 and 6, and at pH 8 the lysin is inactive. It can be dissociated into two subunits of unequal size. Besides being cytolytic in vitro, metridiolysin is lethal when injected intravenously into mice. As shown in Table IV erythrocytes from the horse or dog are about a hundred times as sensitive to lysis as those from the mouse, and erythrocytes from other animals tested are intermediate in sensitivity. 

THCA shows no psychotropic effects, but heating (e.g., by smoking of Cannabis) leads to decarboxylation, which provides the active substance A9-THC. A9-THC is naturally accompanied by its homologous compounds containing a propyl side chain (e.g., tetrahydrocannabivarin, THCV, THC-C3,2.4) or a butyl side chain (THC-C4,2.5). 

Lasers produce spatially narrow and very intense beams of radiation, and lately have become very important sources for use in the UV/VIS and IR regions of the spectrum. Dye lasers (with a fluorescent organic dye as the active substance) can be tuned over a wavelength range of, for instance, 20-50 nm. Typical solid-state lasers are the ruby laser (0.05% Cr/Al203 694.3 nm) and the Nd YAG laser (Nd3+ in an yttrium aluminium garnet host 1.06 pm). 

Human serum albumin (HSA) may be used as a protectant against adsorptive loss of proteins present at low concentrations. HSA is present at higher concentration than the active substance and is preferentially adsorbed, coating the surface of interest and preventing adsorption of the drug. For example, insulin is subject to adsorptive loss to hydrophobic materials. Addition of 0.1-1.0% HSA has been reported to prevent this adsorptive loss [9],... 

Depending on the crop and the physical and chemical properties of the active substance, various portions of the applied amount will evaporate during the drying of the spray mixture and within the first few hours afterwards. 

If a further refinement of the determination of exposure is necessary, an exposure study using the product of concern and conducted under conditions of real practice might be required. The exposure study may include passive dosimetry or biomonitoring, depending on the properties of the active substance and the data on metabolism and toxicokinetics in mammals. 

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