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81.
J. J. Brown R. H. Chinn R. Fraser A. F. Lever J. J. Morton J. I. S. Robertson M. Tree M. A. Waite D. M. Park 《BMJ (Clinical research ed.)》1973,1(5854):650-654
A patient with recurrent weakness and blurring of consciousness associated with hyperkalaemia due to aldosterone deficiency is reported. The plasma concentrations of renin, angiotensin II, and aldosterone were low and did not increase during sodium deprivation. Blood angiotensin I was also low while renin-substrate concentration was normal. Infusion of angiotensin produced a distinct rise in plasma aldosterone. The patient was treated successfully with fludrocortisol.The results support the concept that the renin-angiotensin system is an important regulator of aldosterone secretion and that in the syndrome of acquired selective hypoaldosteronism the primary abnormality may be a deficiency of renin. It is suggested that a selective lack of aldosterone should be considered in all cases of otherwise unexplained hyperkalaemia. 相似文献
82.
Activation of alpha1-adrenergic receptors has been linked to the control of blood pressure, neuroendocrine secretion, reproductive behavior and mood. The present study describes the distribution of alpha1B-adrenergic receptor immunoreactivity in female rat brain regions involved in stress and neuroendocrine function. The pattern of immunolabeling seen resembles that obtained in previous in situ hybridization studies. Several hypothalamic areas that control pituitary function showed intense fiber and/or cell immunolabeling, including the paraventricular nucleus of the hypothalamus, the supraoptic nucleus, and the median eminence. Some regions such as the arcuate nucleus, the median eminence, and dorsal hypothalamus exhibit intense labeling of axonal varicosities, while other regions exhibit only perikarya immunolabeling. alpha1B-adrenergic receptor immunoreactivity was also observed in large pyramidal neurons of layer V of the cerebral cortex, the frontal cortex showing a particularly strong immunoreactivity. Virtually all thalamic regions were labeled, especially the lateral and ventral areas. In addition, labeled cells were present in hippocampus, the medial septum, the horizontal and vertical limbs of the diagonal band of Broca, and the caudate putamen. Finally, some midbrain and hindbrain regions important for motor function were immunoreactive. Because ligands specific for alpha1-adrenergic receptor subtypes are not available, the present immunocytochemical study not only addresses the subcellular and regional distribution of alpha1B-adrenergic receptors but may also provide clues about receptor subtype-specific function. 相似文献
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David A. Sandham Claire Adcock Kamlesh Bala Lucy Barker Zarin Brown Gerald Dubois David Budd Brian Cox Robin A. Fairhurst Markus Furegati Catherine Leblanc Jodie Manini Rachael Profit John Reilly Rowan Stringer Alfred Schmidt Katharine L. Turner Simon J. Watson Jennifer Willis Gareth Williams Caroline Wilson 《Bioorganic & medicinal chemistry letters》2009,19(16):4794-4798
High throughput screening identified a 7-azaindole-3-acetic acid scaffold as a novel CRTh2 receptor antagonist chemotype, which could be optimised to furnish a highly selective compound with good functional potency for inhibition of human eosinophil shape change in whole blood and oral bioavailability in the rat. 相似文献
87.
Mark Andrews Alan Brown Jean-Yves Chiva David Fradet David Gordon Mark Lansdell Malcolm MacKenny 《Bioorganic & medicinal chemistry letters》2009,19(8):2329-2332
The reported selective serotonin Re-uptake Inhibitor Litoxetine was used as the starting point in the design of a range of potential SSRIs with high ease of synthetic accessibility. Preparation and subsequent optimization yielded a range of potent and highly selective SSRIs. 相似文献
88.
Marta Bassitta Joana M. Buades Ana Pérez-Cembranos Valentín Pérez-Mellado Barbara Terrasa Richard P. Brown Pilar Navarro Javier Lluch Jesús Ortega Jose A. Castro Antònia Picornell Cori Ramon 《Zoologica scripta》2020,49(6):668-683
The phylogenetic relationships among the wall lizards of the Podarcis hispanicus complex that inhabit the south-east (SE) of the Iberian Peninsula and other lineages of the complex remain unclear. In this study, four mitochondrial and two nuclear markers were used to study genetic relationships within this complex. The phylogenetic analyses based on mtDNA gene trees constructed with ML and BI, and a species tree using *BEAST support three divergent clades in this region: the Valencia, Galera and Albacete/Murcia lineages. These three lineages were also corroborated in species delimitation analyses based on mtDNA using bPTP, mPTP, GMYC, ABGD and BAPS. Bayesian inference species delimitation method (BPP) based on both nuclear data and a combined data set (mtDNA + nuclear) showed high posterior probabilities for these three SE lineages (≥0.94) and another Bayesian analysis (STACEY) based on combined data set recovered the same three groups in this region. Divergence time dating of the species tree provided an estimated divergence of the Galera lineage from the other SE group (Podarcis vaucheri, (Albacete/Murcia, Valencia)) at 12.48 Ma. During this period, the Betic–Rifian arc was isolated, which could have caused the isolation of the Galera form distributed to the south of the Betic Corridor. Although lizards from the Albacete/Murcia and Galera lineage are morphologically similar, they clearly represent distinct genetic lineages. The noteworthy separation of the Galera lineage enables us to conclude that this lineage must be considered as a new full species. 相似文献
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Matthew I. Daws Jennifer Davies Hugh W. Pritchard Neville A. C. Brown Johannes Van Staden 《Plant Growth Regulation》2007,51(1):73-82
We tested the applicability of the recently identified major germination cue from smoke (a butenolide 3-methyl-2Hfuro[2,3-c]pyran-2-one) on 18 weed species from non-fire prone environments. For the study species we compared the relative effectiveness
of alternating temperatures, KNO3, GA3, smoke water and the butenolide on germination percentage, germination rate and seedling mass. We found that while smoke
stimulated germination in a number of species it also had negative impacts on other species. In addition, the butenolide was
effective on the widest range of species in terms of enhancing germination percentage, rate and seedling mass. However, none
of the treatments, including butenolide were effective on all species. Our data demonstrate that butenolide may have wide
applicability as a germination and seedling growth stimulant irrespective of whether the species come from fire-prone habitats. 相似文献