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871.
K. T. Parsons J. Maisano J. Gregg C. F. Cotton R. J. Latour 《Environmental Biology of Fishes》2018,101(1):137-151
Life history strategies of batoid fishes have evolved within dynamic marine ecosystems. Adaptations in reproductive and developmental biology are paramount to the survival of species, and therefore knowledge of growth rates to maturity is fundamental for identifying constraints on the conservation of populations. The butterfly rays (Myliobatiformes: Gymnuridae) are highly derived batoids with generally low reproductive potentials for which age and growth information remains unknown. In this study we applied high-resolution X-ray computed tomography (HRXCT) to vertebral centra from a stingray for the first time to estimate age, and used a multimodel approach to investigate growth of spiny butterfly ray, Gymnura altavela. Estimated ages of the oldest male and female were 11 and 18 yrs. at disk widths (WD) 1355 mm and 2150 mm, respectively. Disk width-at-age data were analyzed using three growth models (von Bertalanffy, logistic, Gompertz), and the most parsimonious and empirically supported model was the logistic function with sex treated as a fixed effect on asymptotic disk width (WD ∞ ) and k parameters. Model parameter estimates were (males) WD ∞ = 1285.46 ± 67.27 mm, k = 0.60 ± 0.10, and (females) WD ∞ = 2173.51 ± 129.78 mm, k = 0.27 ± 0.04. Results indicated sexually dimorphic growth patterns, with males growing faster and reaching asymptotic size at earlier ages than females. These age and growth results are the first reported for the genus, and suggest that G. altavela grows at a similar rate as some teleosts and batoids, and relatively fast among chondrichthyans. 相似文献
872.
Coral Reefs - Associations between resembling species have been noted long ago by naturalists and have been traditionally interpreted in terms of mimicry, whereby a mimetic species is naturally... 相似文献
873.
Morgane Sonia Thion Donovan Low Aymeric Silvin Jinmiao Chen Pauline Grisel Jonas Schulte-Schrepping Ronnie Blecher Thomas Ulas Paola Squarzoni Guillaume Hoeffel Fanny Coulpier Eleni Siopi Friederike Sophie David Claus Scholz Foo Shihui Josephine Lum Arlaine Anne Amoyo Anis Larbi Sonia Garel 《Cell》2018,172(3):500-516.e16
874.
Sophie Calderari Massimiliano Ria Christelle Gérard Tatiane C. Nogueira Olatz Villate Stephan C. Collins Helen Neil Nicolas Gervasi Christophe Hue Nicolas Suarez-Zamorano Cécilia Prado Miriam Cnop Marie-Thérèse Bihoreau Pamela J. Kaisaki Jean-Baptiste Cazier Cécile Julier Mark Lathrop Michel Werner Dominique Gauguier 《Genomics》2018,110(2):98-111
The GLIS family zinc finger 3 isoform (GLIS3) is a risk gene for Type 1 and Type 2 diabetes, glaucoma and Alzheimer's disease endophenotype. We identified GLIS3 binding sites in insulin secreting cells (INS1) (FDR q < 0.05; enrichment range 1.40–9.11 fold) sharing the motif wrGTTCCCArTAGs, which were enriched in genes involved in neuronal function and autophagy and in risk genes for metabolic and neuro-behavioural diseases. We confirmed experimentally Glis3-mediated regulation of the expression of genes involved in autophagy and neuron function in INS1 and neuronal PC12 cells. Naturally-occurring coding polymorphisms in Glis3 in the Goto-Kakizaki rat model of type 2 diabetes were associated with increased insulin production in vitro and in vivo, suggestive alteration of autophagy in PC12 and INS1 and abnormal neurogenesis in hippocampus neurons. Our results support biological pleiotropy of GLIS3 in pathologies affecting β-cells and neurons and underline the existence of trans?nosology pathways in diabetes and its co-morbidities. 相似文献
875.
Sophie Querouil Florence Magliocca Annie Gautier-Hion 《African Journal of Ecology》1999,37(2):161-167
The structure of the population of forest elephants visiting a clearing in north-west Congo was studied over 8 months. Out of 3314 sightings, 629 elephants were identified (including 64%, of adults). The sex ratio was about 1:1. The number of offspring per female was 1.12. Solitary elephants (91.4%, of males) made up 35% of the population. Of females, 93.6% were grouped. Groups (mean size 3.5) included females and offspring (3.4), males and females (5.0), or males only (2.3). The return rate of elephants at the clearing suggested that up to 1900 individuals have visited the clearing. This confirms that elephant densities are especially high in north Congo. 相似文献
876.
Alberto Ricci Sophie Marchal-Victorion Elena Bronzetti Angelo Parini Francesco Amenta Seyed K Tayebati 《The journal of histochemistry and cytochemistry》2002,50(8):1091-1096
Dopamine D4 receptors mediate inhibition of vasopressin-dependent sodium reabsorption by dopamine in collecting tubules. At present, the distribution of D4 receptors in other renal districts remains an open issue. The renal distribution of D4 receptor was assessed in normally innervated and denervated male Sprague-Dawley rats by quantitative immunohistochemistry using an anti-dopamine D4 receptor rabbit polyclonal antibody. D4 receptor protein immunoreactivity was observed perivascularly in the adventitia and the adventitia-media border. The density of perivascular dopamine D4 receptor was higher in afferent and efferent arterioles than in other segments of the renal vascular tree. Renal denervation abolished perivascular dopamine D4 receptor protein immunoreactivity. In renal tubules, the epithelium of collecting tubules showed the highest dopamine D4 receptor protein immunoreactivity, followed by the epithelium of proximal and distal tubules. No dopamine D4 receptor protein immunoreactivity was observed in the epithelium of the loop of Henle. Denervation did not change dopamine D4 receptor protein immunoreactivity in renal tubules. These results indicate that rat kidney expresses dopamine D4 receptors located both prejunctionally and nonprejunctionally in collecting, proximal, and distal tubules. This suggests that the dopamine D4 receptor may be involved in the control of neurotransmitter release and in renal hemodynamic and tubule function. 相似文献
877.
878.
F. Albert Cotton Akhil R. Chakravarty Derek A. Tocher T. Anthony Stephenson 《Inorganica chimica acta》1984,87(2):115-119
The compounds Os2(O2CCH3)4Cl2,1 and Os(O2CC2H5)4Cl2, 2, have been structurally characterized. Both compounds crystallize in space group P21/n. For 1 the unit cell parameters are a = 6.546(1) Å, b = 8.950(1) Å, c = 12.533(1) Å, β = 90.17(1)° and Z = 2; for 2 they are a = 6.792(2) Å, b = 10.519(3) Å, c = 13.372(4) Å, β = 89.27(3)° and Z = 2. Both molecules have approximate D4th symmetry with important dimensions as follows: for 1, Os≡Os 2.314(1) Å, OsCl 2.448(2) Å; for 2, Os≡Os 2.316(2) Å, OsCl 2.430(5) Å. The mass spectra of these compounds as well as that of Os2(O2CC3H7)4Cl2,3, are reported and discussed. 相似文献
879.
I. Perrault Sophie Châtelin Vanessa Nancy Jean-Michel Rozet Sylvie Gerber Imad Ghazi Eric Souied Jean-Louis Dufier Arnold Munnich Jean de Gunzburg Josseline Kaplan 《Human genetics》1998,102(3):322-326
Leber’s congenital amaurosis (LCA) is the earliest and most severe of all inherited retinal dystrophies. Recently, we mapped
an LCA gene to chromosome 17p13.1 (LCA1) and ascribed the disease to mutations of the retinal guanylate cyclase (ret GC) gene
in a subset of families of North African ancestry. Owing to the genetic heterogeneity of LCA and considering that LCA1 results
from an impaired production of cGMP in the retina (with permanent closure of cGMP-gated cation channels), we hypothesized
that the activation of the cGMP phosphodiesterase (PDE) could trigger the disease by lowering the intracellular cGMP level
in the retina. The rod and cone cGMP-PDE inhibitory subunits were regarded therefore as candidate genes in LCA. Here, we report
the exclusion of five rod and cone cGMP-PDE subunits in LCA families unlinked to chromosome 17p13.
Received: 7 April 1997 / Accepted: 3 November 1997 相似文献
880.