Tolerance causes

Amphotericin B is the drug of choice for treatment of acute C. neoformans meningitis. Amphotericin B, 0.5 to 1 mg/kg/day, combined with flucytosine, 100 mg/kg/day, is more effective than amphotericin alone. In the acquired immune deficiency syndrome (AIDS) population, flucytosine is often poorly tolerated, causing bone marrow suppression and GI distress. 

Sakaguchi, S. et al., Immunologic self-tolerance maintained by activated T cells expressing IL-2 receptor alpha-chains (CD25). Breakdown of a single mechanism of self-tolerance causes various autoimmune diseases, J. Immunol. 155, 1151-1164, 1995. 

FcyRIIb-deficiency results in loss of self-tolerance, causing spontaneous development of systemic vasculitis, at the age of 4-5 months [47, 97-99], The SLC-Tg mice on the FcyRIIb-... 

A unified safety standard for raw and processed foods This amends the Delaney clause in the FFDCA. Under the Delaney clause, a chemical that causes cancer in experimental animals (regardless of dose) shall not be allowed in processed food. Under the FQPA, pesticide residues shown to cause cancer in humans or animals are allowed on food if the EPA determines that the tolerance is safe, meaning that there is a reasonable certainty that no harm will result from exposure to the pesticide. This amendment is necessary mainly because of improved analytical capabilities. Under the Delaney clause, a carcinogen pesticide would be given a zero tolerance in processed food. However, zero tolerance caused many problems. As the analytical sensitivity increased, concentrations that were zero by old methods became measurable. A unified safety standard eliminates longstanding problems posed by multiple standards for pesticides in raw and processed foods. 

The quantity and quality of food in the diet on which insects are reared may affect their size and survival capacity. Variegated cutworm larvae fed peppermint leaves were more tolerant of the insecticides carbaryl, acephate, methomyl, and malathion than larvae fed snap bean leaves. Increased tolerance for carbaryl and methomyl was also observed in larvae of the alfalfa looper and cabbage looper when they were fed peppermint plants instead of their favored host plants alfalfa and broccoli. Furthermore, fall armyworm larvae fed corn leaves became less susceptible to the insecticides methomyl, acephate, methamido-phos, diazinon, trichlorfon, monocrotophos, permethrin, and cypermethrin than those fed soybean leaves. Although nutrition may play some role in these cases, it was found that enhanced insecticide tolerance caused by these host plants was mainly due to plant allelochemicals, which induced detoxification enzymes in the insects (Yu, 1986). 

Acute CNS toxicity, hypertension, tachycardia, tremor and urinary retention occurred in a woman 48 hours after phenelzine was abruptly stopped and isocarboxazid started. In this patient, phenelzine was poorly tolerated causing hypertension and headache. ... 

Sakaguchi, S., Sakaguchi. N..Asano.M., Itoh.M.. and Toda. M. (1995) Immunologic Self-Tolerance Maintained by Activated T Cells Expressing IL-2 Receptor Alpha-Chains (CD25). Breakdown of a Single Mechanism of Self-Tolerance Causes Various Autoimmune Diseases,/. Immunol. 155,1151 1164. 

A process termed oral immune tolerance causes a reduction in the peripheral response to an antigen when that antigen is presented orally. This is the basis of an experimental approach to treat type-I diabetes, in which there may be an autoimmune reaction against the blood glucose regulating hormone, insulin. 

Components exceeding or being lower than the specified tolerances causing interference or location stability problems... 

The lead alkyls and scavengers contained in fuels cause rapid poisoning ol exhaust gas catalytic converters. They are tolerated only in trace quantities in fuels for vehicles having that equipment. The officially allowed content is 0.013 g Pb/1, but the contents observed in actual practice are less than 0.005 g Pb/1. 

Repeated exposures of animals to high (near-lethal) concentrations of vapors result in inflammation of the respiratory tract, as weU as degenerative changes in the Hver, kidneys, and heart muscle. These effects arise at concentrations far above those causing irritation. Such effects have not been reported in humans. The low odor threshold and irritating properties of acrylates cause humans to leave a contaminated area rather than tolerate the irritation. 

Of the water-soluble vitamins, intakes of nicotinic acid [59-67-6] on the order of 10 to 30 times the recommended daily allowance (RE)A) have been shown to cause flushing, headache, nausea, and moderate lowering of semm cholesterol with concurrent increases in semm glucose. Toxic levels of foHc acid [59-30-3] are ca 20 mg/d in infants, and probably approach 400 mg/d in adults. The body seems able to tolerate very large intakes of ascorbic acid [50-81-7] (vitamin C) without iH effect, but levels in excess of 9 g/d have been reported to cause increases in urinary oxaHc acid excretion. Urinary and blood uric acid also rise as a result of high intakes of ascorbic acid, and these factors may increase the tendency for formation of kidney or bladder stones. AH other water-soluble vitamins possess an even wider margin of safety and present no practical problem (82). 

Hydrogen chloride in air is an irritant, severely affecting the eye and the respiratory tract. The inflammation of the upper respiratory tract can cause edema and spasm of the larynx. The vapor in the air, normally absorbed by the upper respiratory mucous membranes, is lethal at concentrations of over 0.1% in air, when exposed for a few minutes. HCl is detectable by odor at 1—5 ppm level and becomes objectionable at 5—10 ppm. The maximum concentration that can be tolerated for an hour is about 0.01% which, even at these levels, causes severe throat irritation. The maximum allowable concentration under normal working conditions has been set at 5 ppm. 

Precipita.tlon. An ink may also be caused to dry by precipitation of its binder rather than by evaporation of solvent. This can be accompHshed by a dding a diluent, such as water in the form of steam or humidity, to a hygroscopic solvent ink system, which causes the solubiHty of the resin in the ink film to decrease sharply and causes it to precipitate when its tolerance for the diluent is reached. Eurther drying is accompHshed by absorption of the solvents into the stock and then by evaporation. Another form of precipitation setting is the quick-set mechanism. This utilizes resins held in solution in a relatively poor solvent, by means of a small amount of an exceUent solvent (called a sweetener) blended with it. When the ink film is printed on the paper, an amount of the solvents is absorbed reducing the content of the sweetener solvent to a point which causes the resins to precipitate and the ink to set. 

The anodes can be made of graphite which tolerates high current densities without passivation, but are subject to gradual corrosive attack causing a... 

Inhalation is the chief route of worker exposure. Comparative data from acute or subchronic inhalation exposures with rats (98) indicate that nitromethane and nitroethane are the least toxic of the nitroparaffins by this route and do not induce methemoglobin formation. The nitropropanes are less well tolerated 2-nitropropane is more toxic than 1-nitropropane and is more likely to cause methemoglobinemia. 

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