Safe, generally

If the drug proves safe and effective, phase III trials are initiated. (In the context of clinical trials, safe and effective are rarely used in the absolute sense. Safe generally refers to a favourable risk beneht ratio, i.e. the benefits should outweigh any associated risk. A drug is rarely 100 per cent effective in all patients. Thus, an acceptable level of efficacy must be defined, ideally prior to trial commencement. Depending upon the trial context, efficacy could be defined as prevention of death/prolonging of life by a specific time-frame. It could also be defined as alleviation of disease symptoms or enhancement of the quality of life of sufferers (often difficult parameters to measure objectively). An acceptable incidence of efficacy should also be defined (particularly for phase II and III trials), e.g. the drug should be efficacious in, say, 25 per cent of all patients. If the observed incidence is below the minimal acceptable level, then clinical trials are normally terminated. 

Only the most general remarks will be made here about the photohydration reaction because, as in the case of dimerization phenomena, most experimental observations have been made on only single compounds and cannot be safely generalized to other pyrimidines. These will therefore be discussed under the headings of individual compounds and any general aspects mentioned at that time. Existing information about the hydration of pyrimidines is summarized in Table I. 

Gordon, B.M. Making the Formulary Safe General Strategies for Reducing Risks. ASHP Medication Use Safety Learning Community, Baltimore, June 2002. NCC MERP council recommendations to reduce medication errors associated with verbal medication orders and prescriptions, adopted February 20, 2001. Available at www.nccmerp.org/council2001-02-20.html, accessed January 9, 2004. 

Halothane (CFsCHClBr) is a safe general anesthetic that has now replaced other organic anesthetics such as CHCI3, which causes liver and kidney damage, and CH3CH2OCH2CH3 (diethyl ethei), which is very flammable. 

The dominant stationary phase in HPLC is modified silica and, to be more specific, octadecyl silica (ODS). It should be pointed out that there could be great differences between various types of ODS materials or even between different batches of the same material. Carbon load, free silanol content, endcapping, type of silica, and coupling chemistry to the Cig moiety, not to mention the several physical characteristics of the packing material all involve the behavior of an ODS column. However, a rather safe generalization is that, in such material, hydrophobic interactions are a dominant mechanism of separation [3-7]. 

Government Performance and Results Act Generally Recognized as Safe Generally Recognized as Safe and Effective Good Review Practice... 

It is likely that the ( )-alkene selective reactions of anionic ylides are due to equlibration of the betaine lithium halide adduct as discussed earlier. However, the balance is delicate and small structural changes can have surprising consequences. Thus, Corey s stereospecific trisubstituted alkene synthesis via /3-oxido ylides (Table 10) is clearly under dominant kinetic control, even though lithium ion is present and aromatic aldehydes can be used as the substrates (54,55). The only obvious difference between the intermediates of Table 10 and oxido ylide examples such as entry 11 in Table 21 is that the latter must decompose via a disubstituted oxaphosphetane while the stereospecific reactions in Table 10 involve trisubstituted analogues. Apparently, the higher degree of oxaphosphetane substitution favors decomposition relative to equilibration. There are few easy and safe generalizations in this field. Each system must be evaluated in detail before rationales can be recommended. 

Static index Safe General Dangerous Very dangerous Extremely dangerous... 

Therefore, we may safely generalize the chemical-biological kinetics in terms of the general rate of biological uptake jS while respecting the chemical... 

Foods or Food Additives (Federal Food, Drug and Cosmetic Act) Reasonable certainty of no harm Food Additive Petition— Food and Drug Administration (FDA) must approve that the material is safe Generally Recognized as Safe— Notifier makes safety determination FDA reviews notification... 

A particular area of risk is the laying of the first sheets, which should be covered specifically in method statements. Standing on stacks of decking sheets is not considered to be safe generally another safe place of work must be provided. 

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