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91.
Allgrove syndrome is a rare autosomal recessive disease with achalasia, alacrima, adrenocortical insufficiency, autonomic neuropathy and other neurological disturbances. A case of two brothers with Addison s disease from early childhood is presented. The younger brother with Addison disease died at the age of 5. The older brother was treated for adrenocortical insufficiency from the age 3, and then treated for achalasia and epilepsy from the age of 5. The patient is currently 26 years old and suffers from achalasia and adrenocortical insufficiency. He also suffers from alacrima, autonomic neuropathy, epilepsy and other damages of the central and peripheral nervous system. The clinical picture is typical for Allgrove or 4A syndrome, and the diagnosis was confirmed by means of molecular analysis of a new AAAS gene mutation. 相似文献
92.
Water uptake and distribution in germinating tobacco seeds investigated in vivo by nuclear magnetic resonance imaging 总被引:4,自引:0,他引:4
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The regulation of water uptake of germinating tobacco (Nicotiana tabacum) seeds was studied spatially and temporally by in vivo (1)H-nuclear magnetic resonance (NMR) microimaging and (1)H-magic angle spinning NMR spectroscopy. These nondestructive state-of-the-art methods showed that water distribution in the water uptake phases II and III is inhomogeneous. The micropylar seed end is the major entry point of water. The micropylar endosperm and the radicle show the highest hydration. Germination of tobacco follows a distinct pattern of events: rupture of the testa is followed by rupture of the endosperm. Abscisic acid (ABA) specifically inhibits endosperm rupture and phase III water uptake, but does not alter the spatial and temporal pattern of phase I and II water uptake. Testa rupture was associated with an increase in water uptake due to initial embryo elongation, which was not inhibited by ABA. Overexpression of beta-1,3-glucanase in the seed-covering layers of transgenic tobacco seeds did not alter the moisture sorption isotherms or the spatial pattern of water uptake during imbibition, but partially reverted the ABA inhibition of phase III water uptake and of endosperm rupture. In vivo (13)C-magic angle spinning NMR spectroscopy showed that seed oil mobilization is not inhibited by ABA. ABA therefore does not inhibit germination by preventing oil mobilization or by decreasing the water-holding capacity of the micropylar endosperm and the radicle. Our results support the proposal that different seed tissues and organs hydrate at different extents and that the micropylar endosperm region of tobacco acts as a water reservoir for the embryo. 相似文献
93.
Two-dimensional gel electrophoresis (2-DE) with immobilized pH gradients was carried out on total cell lysates and membrane fractions of Paracoccus denitrificans with the aim to characterize differences in protein expression during growth under aerobic and various anaerobic conditions (with nitrate, nitrite or nitrous oxide). Comparative image analysis of the protein pattern revealed several subgroups of the total 800 protein spots resolved that were characteristically induced or repressed in response to individual electron acceptors. The respiratory inhibitor azide also exerted a profound influence upon cellular protein composition. However, since most of the proteins showing an altered expression pattern in cells growing on oxygen differed from those in cells growing on nitrite, we suppose that azide acts mainly indirectly, possibly by influencing other cellular signals. Limited information on the P. denitrificans genome has precluded the identification of more than eight protein spots as yet. A public accessible P. denitrificans 2-DE protein database is currently built up at http://www.mpiib-berlin.mpg.de/2D-PAGE. 相似文献
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Control of respiration rate in non-growing cells of Paracoccus denitrificans. 总被引:1,自引:0,他引:1
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By means of fluorimetric measurement and by direct determination of intracellular NAD+ and NADH contents, it was proved that the respiration rate of Paracoccus denitrificans cells utilizing glucose is limited by processes preceding NADH oxidation in the respiratory chain, so that the membrane NADH dehydrogenase is not saturated by its substrate. In the separated membrane fraction on saturation with exogenous NADH the main limiting factor is represented by NADH: ubiquinone oxidoreductase. 相似文献
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Ján Lí?KA Július BRTKO Michal DUBOVICKY Dana MACEJOVá Viktória KISSOVá ?tefan POLáK Eduard UJHáZY 《Experimental Animals》2016,65(1):1-9
The mammary gland is a dynamic organ that undergoes structural and functional changes
associated with growth, reproduction, and post-menopausal regression. The postnatal
transformations of the epithelium and stromal cells of the mammary gland may contribute to
its susceptibility to carcinogenesis. The increased cancer incidence in mammary glands of
humans and similarly of rodents in association with their development is believed to be
partly explained by proliferative activity together with lesser degree of differentiation,
but it is not completely understood how the virgin gland retains its higher susceptibility
to carcinogenesis. During its developmental cycle, the mammary gland displays many of the
properties associated with breast cancer. An early first full-term pregnancy may have a
protective effect. Rodent models are useful for investigating potential breast
carcinogens. The purpose of this review is to help recognizing histological appearance of
the epithelium and the stroma of the normal mammary gland in rats, and throughout its
development in relation to tumorigenic potential. 相似文献
99.
Christiane Schmidt Raphael Morard Ahuva Almogi-Labin Anna E. Weinmann Danna Titelboim Sigal Abramovich Michal Kucera 《PloS one》2015,10(8)
The eastern Mediterranean is a hotspot of biological invasions. Numerous species of Indo-pacific origin have colonized the Mediterranean in recent times, including tropical symbiont-bearing foraminifera. Among these is the species Pararotalia calcariformata. Unlike other invasive foraminifera, this species was discovered only two decades ago and is restricted to the eastern Mediterranean coast. Combining ecological, genetic and physiological observations, we attempt to explain the recent invasion of this species in the Mediterranean Sea. Using morphological and genetic data, we confirm the species attribution to P. calcariformata McCulloch 1977 and identify its symbionts as a consortium of diatom species dominated by Minutocellus polymorphus. We document photosynthetic activity of its endosymbionts using Pulse Amplitude Modulated Fluorometry and test the effects of elevated temperatures on growth rates of asexual offspring. The culturing of asexual offspring for 120 days shows a 30-day period of rapid growth followed by a period of slower growth. A subsequent 48-day temperature sensitivity experiment indicates a similar developmental pathway and high growth rate at 28°C, whereas an almost complete inhibition of growth was observed at 20°C and 35°C. This indicates that the offspring of this species may have lower tolerance to cold temperatures than what would be expected for species native to the Mediterranean. We expand this hypothesis by applying a Species Distribution Model (SDM) based on modern occurrences in the Mediterranean using three environmental variables: irradiance, turbidity and yearly minimum temperature. The model reproduces the observed restricted distribution and indicates that the range of the species will drastically expand westwards under future global change scenarios. We conclude that P. calcariformata established a population in the Levant because of the recent warming in the region. In line with observations from other groups of organisms, our results indicate that continued warming of the eastern Mediterranean will facilitate the invasion of more tropical marine taxa into the Mediterranean, disturbing local biodiversity and ecosystem structure. 相似文献
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