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Initial Evaluation

A statistical analysis allows us to determine whether our results are significantly different from known values, or from values obtained by other analysts, by other methods of analysis, or for other samples. A f-test is used to compare mean values, and an F-test to compare precisions. Comparisons between two sets of data require an initial evaluation of whether the data... [Pg.97]

Initial evaluations of chemicals produced for screening are performed by smelling them from paper blotters. However, more information is necessary given the time and expense required to commercialize a new chemical. No matter how pleasant or desirable a potential odorant appears to be, its performance must be studied and compared with available ingredients in experimental fragrances. A material may fail to Hve up to the promise of its initial odor evaluation for a number of reasons. It is not at all uncommon to have a chemical disappear in a formulation or skew the overall odor in an undesirable way. Some materials are found to be hard to work with in that their odors stick out and caimot be blended weU. Because perfumery is an individuaHstic art, it is important to have more than one perfumer work with a material of interest and to have it tried in several different fragrance types. Aroma chemicals must be stable in use if their desirable odor properties are to reach the consumer. Therefore, testing in functional product appHcations is an important part of the evaluation process. Other properties that can be important for new aroma chemicals are substantivity on skin and cloth, and the abiHty to mask certain malodors. [Pg.84]

Another example is the use of Tc-sestamibi, approved for use in the evaluation of coronary artery disease and myocardial infarction, in patients with breast cancer. Use in breast cancer is under investigation by a number of physicians. The data are not yet sufficient to determine the efficacy of this agent in this setting. Its safety, of course, has already been demonstrated as part of its initial evaluation for heart disease. [Pg.484]

Gani" derived a group contribution method that shows promise. Initial evaluations show average errors of 5 to 10 percent (10-30 K) on a wide variety of compounds, but larger errors can occur. It is recommended that severaf compounds of Known melting point in the same or a similar family be predic ted in order to estimate the probable error. [Pg.389]

Installation of a shut-off valve in the expander exhaust line prevents baekflow during expander isolation (Figure 6-37). Although the need for this valve may not be immediately obvious, it ean be very bene-fieial if the expander is operated for an extended period in the windmilling mode. Often this type of operation is not antieipated during the initial evaluation of valve requirements, but beeomes neeessary at some later date. For example, it is useful when it is deemed prudent... [Pg.375]

The eapabilities of new eoatings are initially evaluated in the laboratory on speeially designed rainbow rotor test rigs to determine their eorrosion resistanee and effeet on meehanieal properties. [Pg.434]

Uncoupled Rate Constants. An initial evaluation of polymerization kinetics is presented in Figure (2), constrained by viscosity invariant rate constants K. The slopes of these straight lines give initial estimates of Rgg/Kp according to Equation (14). Figure 3 presents graphically a power law relationship between K g/Kp and viscosity at 21°C and at 16.6 C. More scatter In Yu s data may be attributed to the use of an older GPC instrument of relatively low resolution. The ratio Kgq/Kp is temperature-sensitive a change of the order or five times is observed if the temperature is reduced by 4.4°C and viscosity is kept constant. [Pg.382]

Acamprosate. Acamprosate (calcium acetylhomotaurinate), an amino acid derivative, affects both GABA and excitatory amino acid (i.e., glutamate) neurotransmission (the latter effect most likely being the one that is important for its therapeutic effects in alcoholism). Initially evaluated in a singlecenter trial in France, acamprosate was shown to be twice as effective as placebo in reducing the rate at which alcoholic patients returned to drinking (Lhuin-tre et al. 1985). The safety and efficacy of the medication have been studied most widely in Europe, and three of these studies provided the basis for the recent approval of acamprosate by the FDA for clinical use in the United States. As with naltrexone, there exist a number of meta-analytic studies that provide consistent evidence of the efficacy of the medication in the treatment of alcohol dependence. [Pg.28]

Knapp (1998) has noted that there is a need to know if additional treatment costs have a downstream pay-off in system-wide cost-effectiveness. This is almost certainly the case for clozapine, but it is less clear for other drugs. Knapp (1998) argues that cost-effectiveness studies need to be part of the initial evaluative process rather than an afterthought. In this respect very new drugs may have an advantage as these calculations can be built into the current registration... [Pg.93]

Loerzel SM, Samuelson DA, Sepulveda MS, Spalding MG, Lewis P, Smith PJ. 1996. Initial evaluation of mercury toxicity in the eye of the great egret. Investig Ophthalmol Vis Sci 37 s349. [Pg.180]

An initial evaluation of the intoxicated patient is needed to determine the level of care indicated. Some patients, although frequent users, may have sufficient ego strength, behavioral control, and capacity to form a treatment alliance to commence treatment in an outpatient setting. Their repeated PCP intoxications may continue for a time, but the intoxication picture is sufficiently benign to allow an outpatient program to be conducted safely, and with a reasonable chance of success. [Pg.270]

To compare the disassembly rate of the above dendritic systems, we synthesized AB3 molecules 18 and 19 (Fig. 5.10). Both the molecules are designed for activation by PGA and have three units of tryptophan as a model drug. Tryptophan was used for initial evaluation as it contains a strong UV chromophore, allowing us to monitor the disassembly reaction. [Pg.126]

Initial Evaluation Identify Precipitants and Correct if Possible... [Pg.334]

Assess patients for improvement of anxiety symptoms and for return to baseline occupational, social, and interpersonal functioning. With effective treatment, the patient should have no or minimal symptoms of anxiety or depression. While drug therapy is being initiated, evaluate patients more frequently to ensure tolerability and response. Increase the dose in patients exhibiting a partial response after 2 to 4 weeks on an antidepressant or 2 weeks on a benzodiazepine. Individualize the duration of treatment because some patients require up to one year of treatment.27... [Pg.613]

When a patient presents with inattention, hyperactivity, academic underachievement, and/or behavior problems, he or she should be evaluated for ADHD. Initial evaluation of the patient primarily should be for the purpose of information gathering. Evidence of the patient s behavior should be... [Pg.635]

Amenorrhea traditionally is described as either primary or secondary in nature. Primary amenorrhea is the absence of menses by age 16 in the presence of normal secondary sexual development or the absence of menses by age 14 in the absence of normal secondary sexual development. Secondary amenorrhea is the absence of menses for three cycles or 6 months in a previously menstruating woman. However, in clinical practice, there is a significant amount of overlap. The initial evaluation of amenorrhea is often the same regardless of age of onset, except in unusual clinical situations.1... [Pg.752]

In a patient presenting with a bleeding or clotting disorder, an initial evaluation should include bleeding time, prothrombin time (PT), activated partial thromboplastin time (aPTT), thrombin time, and platelet count. [Pg.1001]

Becldes MA, Spiro SG, Colice GL, et al. Initial evaluation of the patient with lung cancer Symptoms, signs, laboratory tests, and paraneoplastic syndromes. Chest 2003 123(1 suppl) 97S-104S. [Pg.1339]

New cerebral neurologic symptoms in a cancer patient should initiate evaluation for brain metastases. [Pg.1478]

This step contains an initial evaluation of possible risk to workers due to the toxicity of the plant-protection product. The evaluation is based on the classification and labeling requirements established within the European Community. In order to address the specific need to safeguard the health of workers during re-entry to treated crops, the general safety advice (S-phrases) has to be specified in detail. Delineation of specific instructions for workers regarding classification and labeling is provided below. If no classification or... [Pg.112]

The initial evaluation showed that utilizing fiber-reinforced polymer (FRP) for pipelines is a feasible alternative to steel pipelines with regard to performance and cost [35]. From the cost analysis, an FRP pipe is quite attractive, especially in the regional or distributed service. Currently, spoolable piping manufacturers could install a composite pipeline for serving a 100,000 population for a cost of 250,000-500,000/mi. (does not include the cost for right-of-way), which is well below the DOE s capital cost target in 2017 of 800,000/mi. [35]. From this estimate and cost analyses, it is seen that FRP pipe economics is very attractive, especially for the distribution service. [Pg.362]

Busatto, G. F., Pilowsky, L. S., Costa, D. C. et al. Initial evaluation of 123I-5-I-R91150, a selective 5-HT2A ligand for singlephoton emission tomography, in healthy human subjects. Eur. J. Nucl. Med. 24 119-124,1997. [Pg.959]

A diagnosis of HF should be considered in patients exhibiting characteristic signs and symptoms. A complete history and physical examination with appropriate laboratory testing are essential in the initial evaluation of patients suspected of having F1F. [Pg.96]

Because contrast studies are expensive, invasive, and technically difficult to perform and evaluate, noninvasive tests (e.g., ultrasonography, computed tomography scans, and the ventilation-perfusion scan) are used frequently for the initial evaluation of patients with suspected VTE. [Pg.178]

Patient age and hormonal status in women should be considered in the initial evaluation of patients with skin disorders. Older patients are predisposed to developing psoriasis, seborrhea, and other skin conditions. Atopic dermatitis is most likely to occur in children. Menopausal women tend to develop brown hyperpigmentation, or melasma. Pregnant women may develop hyperpigmentation of the areola and genitalia as well as melasma. [Pg.211]

Initial evaluation of anemia involves a complete blood cell count (Table 33-2), reticulocyte index, and examination of the stool for occult blood. [Pg.378]

The management of a patient with a UTI includes initial evaluation, selection of an antibacterial agent and duration of therapy, and follow-up evaluation. [Pg.559]

Although magnetic resonance imaging is very useful (especially imaging of the temporal lobes), computed tomography typically is not helpful except in the initial evaluation for a brain tumor or cerebral bleeding. [Pg.591]


See other pages where Initial Evaluation is mentioned: [Pg.4]    [Pg.221]    [Pg.160]    [Pg.486]    [Pg.212]    [Pg.506]    [Pg.80]    [Pg.294]    [Pg.335]    [Pg.209]    [Pg.50]    [Pg.51]    [Pg.138]    [Pg.91]    [Pg.118]    [Pg.224]    [Pg.147]    [Pg.160]    [Pg.30]    [Pg.74]    [Pg.291]    [Pg.902]    [Pg.198]   


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