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91.
Jacek Najda Jan Gmiński Marian Dróżdż Alojzy danch 《Biological trace element research》1993,37(2-3):107-114
The influence of silicon treatment on the levels of calcium and magnesium in blood serum and tissues was studied in rats.
The concentrations of both elements were estimated in samples of sera and tissues of rats receiving per os a soluble, inorganic
silicon compound—sodium metasilicate nonahydrate (Na2SiO3·9H2O (REACHIM, USSR)), dissolved in the animals' drinking water. A decrease of magnesium concentration in serum was observed
with accompanying elevation of registered calcemia. Moreover, a reduction of tissue calcium levels was found with a simultaneous
increase of magnesium tissue pool.
The results provide evidence for silicon involvement in mineral metabolism. It could result in a modification of pathological
processes concerning bone tissue. 相似文献
92.
B‐cell differentiation is one of the most recognized examples of the progressive lineage commitment that is distinctive for stem cell systems. However, the characteristics of the stage just before a cell becomes restricted to the B‐cell lineage are less understood. Using single‐cell RNA sequencing technology, Rolink and colleagues are able to define the cellular heterogeneity at this step and challenge our understanding of developmental trajectories in early B‐lymphoid development (Alberti‐Servera et al, 2017 ). 相似文献
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Jan Kvíčala Václav Zamrazil Jarmila Čeřovská Jiří Bednář Jaroslav Janda 《Biological trace element research》1995,47(1-3):365-375
Blood serum selenium of 65 men and hair selenium of 77 men from three regions of the Czech Republic (CR) were analyzed by neutron activation analysis, and 202 samples of urine from the same populations were analyzed for Se by the fluorimetric method to assess selenium status of these regions. Low status (53 μg Se/L of serum and 0.29 μg Se/g lyophilized hair as means) and very low urine selenium (8.7 μg/L urine) were detected. By these data, the CR is among the countries with the lowest Se intake. A comparison of studied regions is presented. Moreover, values of serum zinc were within the reference range, but mild to moderate deficiency in the supply of iodine was detected. 相似文献
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Richard M. McCourt Louise A. Lewis Paul K. Strother Charles F. Delwiche Norman J. Wickett Jan de Vries John L. Bowman 《American journal of botany》2023,110(5):e16175
Green plants, broadly defined as green algae and the land plants (together, Viridiplantae), constitute the primary eukaryotic lineage that successfully colonized Earth's emergent landscape. Members of various clades of green plants have independently made the transition from fully aquatic to subaerial habitats many times throughout Earth's history. The transition, from unicells or simple filaments to complex multicellular plant bodies with functionally differentiated tissues and organs, was accompanied by innovations built upon a genetic and phenotypic toolkit that have served aquatic green phototrophs successfully for at least a billion years. These innovations opened an enormous array of new, drier places to live on the planet and resulted in a huge diversity of land plants that have dominated terrestrial ecosystems over the past 500 million years. This review examines the greening of the land from several perspectives, from paleontology to phylogenomics, to water stress responses and the genetic toolkit shared by green algae and plants, to the genomic evolution of the sporophyte generation. We summarize advances on disparate fronts in elucidating this important event in the evolution of the biosphere and the lacunae in our understanding of it. We present the process not as a step-by-step advancement from primitive green cells to an inevitable success of embryophytes, but rather as a process of adaptations and exaptations that allowed multiple clades of green plants, with various combinations of morphological and physiological terrestrialized traits, to become diverse and successful inhabitants of the land habitats of Earth. 相似文献
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