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1.
ANP (atrial natriuretic peptide), a peptide found in granules of mammalian atrial cardiac myocytes, has been shown to be active in regulation of blood pressure and body water homeostasis. The existence of ANP in atrium, pituitary, adrenal gland, and kidney of the rat had been immunocytochemically demonstrated with an antibody against rat ANP (102-126). We used the same antibody in immunocytochemical studies for the detection of ANP in peripheral organs of the tree shrew (Tupaia belangeri). The antibody stained granules in myocytes of cardiac atria which indicated that it reacted with tree shrew ANP. In contrast to the rat, no immunoreactive cells were found in pituitaries and adrenal glands. However, in the kidneys distal tubules in outer medulla and cortex were labeled. Ascending limbs of distal tubules were intensely stained when either the peroxidase-antiperoxidase (PAP) or the indirect immunofluorescence method were used. Collecting ducts and convoluted distal tubules in the outer cortex showed a granular type of staining when the immunofluorescence method was used. These data indicate that ANP is present in epithelial cells of distal tubules and collecting ducts, where it may be involved in the regulation of renal salt excretion. 相似文献
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Summary The protective effect of a nutrient solution upon young forest plants, seriously stressed by de-icing salt (NaCl) were investigated.
The results show, that the adsorbed salt ions in the soil are already exchanged at low concentrations (2 bars), whilst plant
survival and growth showed only at higher concentrations (10 bars) a significant optimum. 相似文献
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The 3'-orf protein of human immunodeficiency virus 2 shows sequence homology with the bel3 gene of the human spumaretrovirus 总被引:10,自引:0,他引:10
The primary amino acid sequence within a domain of 89 residues of the central part of the 3'-orf protein (p27 3'-orf) of human immunodeficiency virus (HIV-2) shares homology with the middle and carboxy-terminal portion of the bel3 gene product of human spumaretrovirus (HSRV). In addition, a limited region of the tat protein of HIV-2 but not HIV-1 shows a 28% degree of homology to the deduced protein sequence of the bel1 gene product of HSRV. Comparison between the viral sequences suggests that the 3'-orf and bel1 gene product of HSRV could serve similar functions to those in HIV-2. 相似文献
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Brasil Flávia Bittencourt Gobbo Rênata Cristina Bertolini de Almeida Fhelipe Jolner Souza Luckachaki Matheus Dargesso dos Santos Petry Fernanda de Oliveira Marcos Roberto 《Neurochemical research》2021,46(4):740-754
Neurochemical Research - Methylglyoxal (MG) is a reactive dicarbonyl presenting both endogenous (e.g. glycolysis) and exogenous (e.g. food cooking) sources. MG induces neurotoxicity, at least in... 相似文献
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Danilo E. F. L. Fl?res Barbara M. Tomotani Patricia Tachinardi Gisele A. Oda Veronica S. Valentinuzzi 《PloS one》2013,8(7)
Subterranean rodents spend most of the day inside underground tunnels, where there is little daily change in environmental variables. Our observations of tuco-tucos (Ctenomys aff. knighti) in a field enclosure indicated that these animals perceive the aboveground light-dark cycle by several bouts of light-exposure at irregular times during the light hours of the day. To assess whether such light-dark pattern acts as an entraining agent of the circadian clock, we first constructed in laboratory the Phase Response Curve for 1 h light-pulses (1000lux). Its shape is qualitatively similar to other curves reported in the literature and to our knowledge it is the first Phase Response Curve of a subterranean rodent. Computer simulations were performed with a non-linear limit-cycle oscillator subjected to a simple model of the light regimen experienced by tuco-tucos. Results showed that synchronization is achieved even by a simple regimen of a single daily light pulse scattered uniformly along the light hours of the day. Natural entrainment studies benefit from integrated laboratory, field and computational approaches. 相似文献
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