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Experimental studies human

In an experimental study, humans exposed to 100ppm for 2.5 minutes experienced irritation of eyes, nose, and throat, whereas 50 ppm produced lesser irritation. Distortion of vision can occur at levels much lower than those that cause irritation. Workers exposed to low vapor concentrations (3-11 ppm) for several hours reported temporary fogged vision with rings around lights. Corneal edema has been observed in workers when air concentrations of substituted morpholines exceed 40 ppm. The symptoms usually appear at the end of the workday and clear within 3-4 hours after cessation of exposure. ... [Pg.337]

The cultivation of viruses from material taken from lesions is an important step in the diagnosis of many viral diseases. Studies of the basic biology and multiplication processes of human viruses also require that they are grown in the laboratory under experimental conditions. Human pathogenic viruses can be propagated in three types of cell systems. [Pg.66]

It has been known for many years that antimuscarinic drugs like hyoscine, which enter the brain, cause amnesia when used clinically, e.g. pre-operatively, to reduce bronchial secretions. In experimental studies in both humans and animals they disrupt both the acquisition and the performance of learned behaviour. Anti-cholinestrase drugs have the opposite effect. It is by no means certain, however, that the memory defects induced by antimuscarinics are identical to those seen in AzD. [Pg.383]

The sterols and sterolins in rice bran are potent immunomodulators. The best response was obtained with a 100 1 sterol/sterolin mixture that demonstrated T-cell proliferation from 20% to 920% and active cell antigens after four weeks in human subjects (Bouic et al, 1996). Another in vitro experimental study with sterol/sterolins, demonstrated a significant increase in cytokinines, interleukin-2 and y-interferon between 17% and 41 % in addition to an increase in natural killer cell activity. These experiments (Bouic et al, 1996) prove that sterol/sterolins are potent immunomodulators with important implications for the treatment of immune dysfunction. Rice bran products are excellent dietary supplements for the improvement of immune function. It is probable that the effects of rice bran on diabetes, CVD and cancer all result from improved immune function. [Pg.369]

The presence of particles in the brains of experimental rats and humans exposed to asbestos has been reported (Pontefiart and Cunningham, 1973 Auerbach et al., 1980). In experimental studies, particles of Teflon, a reflux paste, enter the brain via intravascular transport when injected into the bladder (Aaronson et al., 1993). Encephalitic reactions to accumulated calcium oxalate crystals in the brain as a result of infusions of glucose surrogate polyol solutions have been described (PciflPcr etal., 1984). Such studies indicate the capacity of particulates to enter the brain and thus pose a potential pathological threat to the functioning of the central nervous system (CNS). [Pg.252]

Effects In Humans. Neither postmortem nor functional cerebrospinal fluid (CSF) studies in humans provide firm evidence for similar, long-term damages or alterations to monoaminergic neurons in chronic stimulant abusers. In part, the lack of demonstrable neurochemical changes may well be due to the obvious preclusion of well-controlled prospective experimentation in humans, as well as to variability in critical variables (e.g., individual sensitivity or pattern of abuse) encountered in clinical research. Possible relationship of the various complications of stimulant abuse including hyperpyrexia, seizure, anoxia, and metabolic exhaustion to neuronal chromatolysis, terminal destruction, and monoamine and enzymatic depletion have not been systematically explored in human autopsy eases. It should be also noted that, under nonperturbed conditions, overt behavioral deficits are rare in... [Pg.332]

To reduce mortality, administration of an aldosterone antagonist, either eplerenone or spironolactone, should be considered within the first 2 weeks following MI in all patients who are already receiving an ACE inhibitor (or ARB) and have an EF of equal to or less than 40% and either heart failure symptoms or diagnosis of diabetes mellitus.3 Aldosterone plays an important role in heart failure and in MI because it promotes vascular and myocardial fibrosis, endothelial dysfunction, hypertension, left ventricular hypertrophy, sodium retention, potassium and magnesium loss, and arrhythmias. Aldosterone antagonists have been shown in experimental and human studies to attenuate these adverse effects.70 Spironolactone decreases all-cause mortality in patients with stable, severe heart failure.71... [Pg.102]

Experimental Studies on the Inhalation of Lead by Human Subjects. Pure... [Pg.215]

Experimental design (human study details or strain, number of animals per exposure/control groups, sex, dose administration details) ... [Pg.216]

Although experimental studies provide significant amounts of information regarding the structure and the catalytic activity of these enzymes, several issues concerning the structure (presence of water in the active site) and the catalytic mechanism remained unresolved. Based on the complete X-ray structure of human plasma GPx (2.9 A resolution) [64], we performed active-site and ONIOM QM MM calculations of structure and reaction mechanism [27, 28, 65],... [Pg.39]

Experimental studies showed antitumoral effects of raloxifene in different in vitro preparations and animal models. Raloxifene has been able to inhibit the mitogenic effect induced by estrogens on ZR-75-1 cells, an estrogen responsive human breast cancer cell line (Poulin et al. 1989). In a well-accepted rat model of breast cancer induced by nitroso-methyl urea (NMU) raloxifene significantly suppressed the development of breast tumors and acted synergistically with 9 cis-retinoic acid (Anzano et al. 1996). [Pg.264]

Experimental studies with human subjects and several mammalian species (monkey, dog, rat, mouse, and rabbit) were located. Animal studies addressed neurotoxicity, genotoxicity, carcinogenicity, and cardiac sensitization and were conducted over acute, subchronic, and chronic exposure durations. [Pg.141]

There is no experimental evidence available to assess whether the toxicokinetics of -hexane differ between children and adults. Experiments in the rat model comparing kinetic parameters in weanling and mature animals after exposure to -hexane would be useful. These experiments should be designed to determine the concentration-time dependence (area under the curve) for blood levels of the neurotoxic /7-hcxane metabolite 2,5-hexanedione. w-Hcxanc and its metabolites cross the placenta in the rat (Bus et al. 1979) however, no preferential distribution to the fetus was observed. -Hexane has been detected, but not quantified, in human breast milk (Pellizzari et al. 1982), and a milk/blood partition coefficient of 2.10 has been determined experimentally in humans (Fisher et al. 1997). However, no pharmacokinetic experiments are available to confirm that -hexane or its metabolites are actually transferred to breast milk. Based on studies in humans, it appears unlikely that significant amounts of -hexane would be stored in human tissues at likely levels of exposure, so it is unlikely that maternal stores would be released upon pregnancy or lactation. A PBPK model is available for the transfer of M-hcxanc from milk to a nursing infant (Fisher et al. 1997) the model predicted that -hcxane intake by a nursing infant whose mother was exposed to 50 ppm at work would be well below the EPA advisory level for a 10-kg infant. However, this model cannot be validated without data on -hexane content in milk under known exposure conditions. [Pg.170]

Experimental Design (Human study details or strain, number of animals per exposure/control group, sex, dose administration details) Endrin was administered at doses of 0.15, 0.20, 0.25, 0.29, 0.49, 0.53, 1.21, and 2.50 mg/kg/day in the diet of dogs for 18 days to 9.9 months, 6 days per week. [Pg.198]


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