Aberration-tolerance

A circular spot is more aberration-tolerant than a line of the same area and thus can be demagnified further (Hirschfeld, 1977). In other words, the Raman radiation of a smaller spot on the sample can be collected within a larger solid angle. This means a further optimization of the arrangement. 

PCP concentrations in blood of 20 workers ranged between 0.023 and 0.775 mg/L and were below the biological tolerance value of 1.0 mg/L no effect on sister chromatid exchange or chromosomal aberrations (Ziemsen et al. 1987)... 

Regulation of Peripheral T-Cell Tolerance and Aberrations in Allergic Diseases... 

In agreement with the aberrant HDAC/HAT activity equilibrium in cancer, HDAC inhibitors have been shown to induce cell-cycle arrest, terminal differentiation and/or apoptosis in a broad spectrum of human tumor cell Unes in vitro, to inhibit angiogenesis and to exhibit in vivo antitumor activity in human xenograft models in nude mice [10-12]. Several HDAC inhibitors are in advanced stages of development and antitumor activity has been observed in hematological malignancies at doses that were well tolerated (Sect. 3). 

Aberrations in chromosomes or chromatids, which are sometimes microscopically visible, may arise during mitotic division when newly divided chromosomes fail to separate or do so incorrectly. The absence of a chromosome is usually lethal, and an excess is often poorly tolerated, giving rise to serious defects. Aberrations of the sex chromosomes are more readily tolerated, however. Chromosome aberrations may be caused by foreign compounds as indicated in the section on mutagenesis (see chap. 6). However, those cells with aberrations seem to be rapidly eliminated and so may contribute to cell death rather than a heritable mutation. 

Spontaneous human autoimmunity seems to be almost entirely restricted to the autoantibody responses produced by B-lymphocytes. Loss of tolerance by T-ceUs has been extremely hard to demonstrate, and where there is evidence for an abnormal T-ceU response it is usually not to the antigen recognised by the autoantibody. This disparity has led to the idea that human autoimmune disease is in most cases (with probable exceptions including type I diabetes) based on a loss of B-cell tolerance, which makes use of normal T-cell responses to foreign antigens in a variety of aberrant ways. 

Long-term use of large doses of ephedrine (350-2500 mg day for 3-20 years) may produce psychotic episodes characterized by paranoia, hallucinations, depression, and bizarre mentation. Following withdrawal of the drug, aberrant mental effects will resolve but reinstitution of ephedrine use may result in a return of the psychotic symptoms. A tolerance may develop with chronic use, allowing larger doses. Tolerance is lost after 4-6 weeks of removal from the drug. 

A double-blind crossover trial in which clomipramine was directly compared to haloperidol and placebo in 36 autistic adolescents and adults failed to demonstrate any advantages of clomipramine over haloperidol with respect to Aberrant Behavior Checklist (ABC) measures of hyperactivity and irritability. Although no serious adverse effects were reported, tolerability of clomipramine was significantly worse than haloperidol, with over half of the subjects being unable to complete the clomipramine phase of the study due to adverse effects and/or lack of efficacy. An open-label sfudy also reporfed a high frequency of adverse effects (Sanchez et al.. 

For the purposes of this study, hexaploid wheat and certain other polyploids are important because they are often subject to a so-called genetic buffering (c/. Mac Key, 1967), which permits tolerance of gross chromosomal aberrations and even loss of whole chromosomes. Such effects, no doubt, are of concern as a hazard to man from certain environmental factors. Wheat, in contrast to diploid barley and pea, offers the possibility to measure such effects inherited as gene mutations, i.e., affecting morphological characters. 

Rosenthal, G. A., M. A. Berge, J. A. Bleiler, and T. P. Rudd, Aberrant, canavalyl protein formation and the ability to tolerate or utilize L-canavanine, Experientia, 43, 558-561 (1987). 

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