Gestation, human

An intermediate-duration oral MRL of 0.0007 mg/kg/day was derived for methyl parathion based on the observation of electrophysiological effects in the central and peripheral nervous systems of male rats exposed to methyl parathion through gavage administration of 0.22 mg/kg/day to the dams on days 5-15 of gestation and days 2-28 of lactation, followed by direct administration of the same dose to the male pups for 8 weeks. More marked effects occurred at the two higher doses, 0.44 and 0.88 mg/kg/day. The effects were dose-related, and were statistically significant at all three dose levels. The MRL was derived by dividing the LOAEL from this study (0.22 mg/kg/day) by an uncertainty factor of 300 (3 for a minimal LOAEL, 10 for extrapolation from animals to humans, and 10 for human variability). 

Senior s text is found in Eberhard Zetzner (ed.), Theatrum chemicum Praecipuos Selectorum Auctorum (Strassburg Heredium Eberhard Zetzner, 1622) 5, 193-239 Senioris Zadith, filii Hamuefis Tabula Chemica. This deals with the making of the stone on the model of the human body. It is gestated in nine months. On page... 

The POMC protein is processed differendy in the anterior lobe than in the intermediate lobe. The intermediate lobe of the pituitary is mdimentary in adult humans, but it is active in human fetuses and in pregnant women during late gestation and is also active in many animal species. Processing of the POMC protein in the peripheral tissues (gut, placenta, male reproductive tract) resem-... 

The major Impetus to the development of methods for the prenatal detection of genetic disorders derives. In historical terms, from the roughly simultaneous development of three major techniques (11-14). One was the technique, and the willingness to use It, for obtaining samples of amnlotlc fluid early In gestation. The second was the development of techniques for the culture of human cells in vitro, and the third was the development of better techniques for cytogenetic analysis. As will be described below, with the availability of these three techniques It became possible first to work out methods for the examination of fetal chromosomes, and then, by extension, to devise ways of determining other characteristics of the fetus. 

The process of retinal vascularization is unique. Before the fourth month of gestation, there are no blood vessels in the human retina, the inner layers being nourished by the embryonic system of hyaloid vessels in the vitreous. 

Positive urine human chorionic gonadotropin followed by positive ultrasound, fetal heart sounds, and/or fetal movement. Pregnancy Dating and Gestational Age Calculated from the first day of the last menstrual period. 

Exchanges between bone and soft tissue stores of americium would be expected to be more rapid during periods of active bone metabolism such as infancy and childhood, pregnancy, and menopause. Thus, it is possible that, in humans, some of the maternal bone americium stores may be transferred to the fetus during gestation and may be incorporated into fetal bone during the development of the fetal skeleton. 

Pregnant rats exposed to 75 ppm of hydrogen sulfide from gestation days 1-21 had 50% increases in glucose levels (Hayden et al. 1990a). The relevance of this finding to humans is not known. 

This section discusses potential health effects from exposures during the period from conception to maturity at 18 years of age in humans, when all biological systems will have fully developed. Potential effects on offspring resulting from exposures of parental germ cells are considered, as well as any indirect effects on the fetus and neonate due to maternal exposure during gestation and lactation. Relevant animal and in vitro models are also discussed. 

Cat, Fells domesticus Human, Homo sapiens adult Human, adult Human, adult Human, adult 250 pg/kg BW daily on days 10 to 58 of gestation oral route 50 pg/day 200 pg/day 1000 pg/day 50 pg Hg/m3air for 8 h... 

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