Respondents estimating individual

It is unlikely that a victim of a terrorist attack will use the information in Table 3.2. This information may, however, be useful to emergency responders and medical personnel during triage to identify the most highly exposed individuals. The information may also be useful to postattack investigators who must reconstruct the crime scene and estimate doses to all potential victims. 

Radiation-induced genomic instability and bystander effects are now well-established consequences of exposure of living cells to ionizing radiation. Cells not directly traversed by radiation may still exhibit radiation effects. This phenomenon, known as bystander effect, has become a major activity in radiation biology and in some cases has challenged the conventional wisdom. An example is the currently accepted models used for low-dose extrapolation of radiation risks. The currently used models assume that cells in an irradiated population respond individually rather than collectively. If bystander effects have implications for health risks estimates from exposure to ionizing radiation, then the question of whether this is a general phenomenon or solely a characteristic of a particular type of cell and the radiation under test becomes an important issue. 

Figure 5.9. Dose-response profile in a population. (A) Relationship between responding patients, expressed as percentage of individuals, and plasma drug concentrations. With increasing drug concentration, the proportion of patients who derive therapeutic benefit, without concentration-limited side effect peaks, and then declines. (B) A schematic representation of dose-response curves. Typical therapeutic and lethal responses at indicated doses are evaluated in animal models to estimate therapeutic index, TI. ED50, effective dose needed to produce a therapeutic response in 50% of animals, exhibiting therapeutic response LD50, effective dose needed to produce lethal effects in 50% of animals.

Hepatitis C virus (HCV) was discovered in 1989 and has been regarded as the key causative agent for non-A, non-B virus hepatitis (33-35). It is estimated that there are over 170 million people worldwide and about 4 million individuals in United States with chronic HCV infection (36). Majority of the infected persons (80%) develop chronic hepatitis, where about 10-25% of them could advance to serious HCV-related liver diseases such as fibrosis, cirrhosis, and hepatocellular carcinoma (37). Only a fraction of patients respond to current FDA-approved standard therapy with a sustained viral load reduction (38), and many of them could not tolerate the treatment because of the various severe side effects (39). Therefore, HCV still represents an unmet medical need which requires discovery and development of more effective and well-tolerated therapies. 

In a 1.0-L sample of N2 gas (10.0 cm on a side) at 25°C and 1.0 atm pressure, what is the rms velocity of N2 molecules What is the average z component of velocity Estimate how often a single molecule hits a particular wall. What is the total rate of impacts with this wall Do you think that there is any pressure gauge that could respond to these individual impacts ... 

The NAC/AEGL Committee estimates the range in variability of response to specific chemical exposures primarily on the basis of quantitative human data. Acceptable experimental data are more likely to be available for AEGL-1 and AEGL-2 endpoints than for AEGL-3 endpoints. For example, numerous studies have considered induction of bronchospasm after controlled exposmes to sulfur dioxide (SO2) in asthmatic and nonasthmatic individuals (see references below). There is marked individual variability in the severity of reaction to inhalation of low concentrations of SO2. Asthmatics, individuals with hyper-reactive airways, smokers, and those with chronic respiratory or cardiac disease respond at relatively lower concentrations (Aleksieva 1983 Simon 1986). Susceptibility may also be increased in people over 60 years of age, but reports have not been consistent (Rondinelli et al. 1987 Koenig et al. 1993). By contrast, comparable human data for AEGL-3 tier concentrations are limited to anecdotal case reports. 

Two practical concerns of the critics of use of HRQOL assessments in individual patient care are 1) respondent burden and 2) reliability of scores obtained from shorter questionnaires. Current researchers struggle with the competing demands invoked by everyday use requiring shorter forms and the reliability of a result obtained from fewer questions. Specifically, concerns are raised about the reliability of the result and the interpretation. With popular outcomes measures, the standard error around a single person estimate is large and not satisfying enough to ensure stable conclusions. 

OTA was unable to obtain much information about the structure of such accounting systems hence, the ability of firms to identify expenditures by clinical phase is unclear. All companies would have an accurate picture of monthly charges to individual project accounts, however, and the dates at which phase I, phase II, and phase III trials began are available to companies, so allocation of costs by date is a reasonable approach to estimating the distribution of costs by phase. If companies responded to survey questions with this approach, the phase-specific estimates would be reasonably accurate. 

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