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121.
Susan M. Theiss Thomas J. Lisney Shaun P. Collin Nathan S. Hart 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2007,193(1):67-79
Relatively little is known about the physical structure and ecological adaptations of elasmobranch sensory systems. In particular,
elasmobranch vision has been poorly studied compared to the other senses. Virtually nothing is known about whether elasmobranchs
possess multiple cone types, and therefore the potential for colour vision, or how the spectral tuning of their visual pigments
is adapted to their different lifestyles. In this study, we measured the spectral absorption of the rod and cone visual pigments
of the blue-spotted maskray, Dasyatis kuhlii, using microspectrophotometry. D. kuhlii possesses a rod visual pigment with a wavelength of maximum absorbance (λmax) at 497 nm and three spectrally distinct cone types with λmax values at 476, 498 and 552 nm. Measurements of the spectral transmittance of the ocular media reveal that wavelengths below
380 nm do not reach the retina, indicating that D. kuhlii is relatively insensitive to ultraviolet radiation. Topographic analysis of retinal ganglion cell distribution reveals an
area of increased neuronal density in the dorsal retina. Based on peak cell densities and using measurements of lens focal length
made using laser ray tracing and sections of frozen eyes, the estimated spatial resolving power of D. kuhlii is 4.10 cycles per degree. 相似文献
122.
Bendlová B Zavadilová J Vanková M Vejrazková D Lukásová P Vcelák J Hill M Cibula D Vondra K Stárka L Vrbíková J 《The Journal of steroid biochemistry and molecular biology》2007,104(1-2):68-74
SHBG (sex hormone-binding globulin) is a transport protein specific for dihydrotestosterone, testosterone and estradiol. The missense mutation in exon 8 (GAC-->AAC) causing the amino acid exchange Asp-->Asn in codon 327 (D327N) correlates according to the published data with increased SHBG levels. We studied possible association of this polymorphism with polycystic ovary syndrome (PCOS) and anthropometric and biochemical parameters in 248 PCOS patients and 109 healthy control women. The D327N polymorphism (wild-type and variant allele) was detected using PCR-RFLP method (restriction enzyme Bbs-I). For statistical evaluation chi(2) test, Mann-Whitney test, ANCOVA, ANOVA (NCSS 2004, Statgraphics Plus v.5.1, USA) were used. There was no significant difference in genotype distribution between PCOS and controls (chi(2)=1.03, p=0.59). Moreover, we did not find an association of the variant allele with plasma SHBG level, steroid hormones, or screened parameters of lipid and glucose metabolism. In conclusion, the D327N polymorphism of the SHBG gene does not influence susceptibility to PCOS. 相似文献
123.
DC homeostasis in hematopoietic stem cell transplantation 总被引:1,自引:0,他引:1
Hematopoietic stem cell transplantation is an important experimental tool and therapeutic modality. Its efficacy and toxicity are both linked to a GvH reaction that is initiated by donor T cells recognizing recipient APC, of which DC are the most potent. In most tissues recipient DC are replaced after transplantation because they turnover rapidly from BM-derived precursors. However, in a number of sites, notably the skin, recipient DC may persist and even self-renew for many months after transplantation. Understanding the homeostasis of different APC populations and how they are related to the induction of alloreactivity may help to improve the therapeutic benefit of transplantation. 相似文献
124.
Helena J Bailes Wayne L Davies Ann EO Trezise Shaun P Collin 《BMC evolutionary biology》2007,7(1):200
Background
One of the greatest challenges facing the early land vertebrates was the need to effectively interpret a terrestrial environment. Interpretation was based on ocular adaptations evolved for an aquatic environment millions of years earlier. The Australian lungfish Neoceratodus forsteri is thought to be the closest living relative to the first terrestrial vertebrate, and yet nothing is known about the visual pigments present in lungfish or the early tetrapods. 相似文献125.
Bett Nolan N. Hinch Scott G. Bass Arthur L. Braun Douglas C. Burnett Nicholas J. Casselman Matthew T. Cooke Steven J. Drenner S. Matthew Gelchu Ahmed Harrower William L. Ledoux Roxx Lotto Andrew G. Middleton Collin T. Minke-Martin Vanessa Patterson David A. Zhang Wenming Zhu David Z. 《Hydrobiologia》2022,849(2):385-405
Hydrobiologia - Many of the world’s rivers are dammed, altering the physiology, behaviour, ecology and survival of fish. Integrative research has the potential to improve our understanding of... 相似文献
126.
Říha Milan Rabaneda-Bueno Ruben Jarić Ivan Souza Allan T. Vejřík Lukáš Draštík Vladislav Blabolil Petr Holubová Michaela Jůza Tomas Gjelland Karl Ø. Rychtecký Pavel Sajdlová Zuzana Kočvara Luboš Tušer Michal Prchalová Marie Seďa Jaromír Peterka Jiří 《Hydrobiologia》2022,849(15):3351-3371
Hydrobiologia - To understand the spatiotemporal overlap in the habitat use of sympatric predators, we studied longitudinal activity and reservoir section and depth use of pike (Esox lucius),... 相似文献
127.
128.
Michail Rovatsos Jasna Vuki? Petros Lymberakis Luká? Kratochvíl 《Proceedings. Biological sciences / The Royal Society》2015,282(1821)
Amniote vertebrates possess various mechanisms of sex determination, but their variability is not equally distributed. The large evolutionary stability of sex chromosomes in viviparous mammals and birds was believed to be connected with their endothermy. However, some ectotherm lineages seem to be comparably conserved in sex determination, but previously there was a lack of molecular evidence to confirm this. Here, we document a stability of sex chromosomes in advanced snakes based on the testing of Z-specificity of genes using quantitative PCR (qPCR) across 37 snake species (our qPCR technique is suitable for molecular sexing in potentially all advanced snakes). We discovered that at least part of sex chromosomes is homologous across all families of caenophidian snakes (Acrochordidae, Xenodermatidae, Pareatidae, Viperidae, Homalopsidae, Colubridae, Elapidae and Lamprophiidae). The emergence of differentiated sex chromosomes can be dated back to about 60 Ma and preceded the extensive diversification of advanced snakes, the group with more than 3000 species. The Z-specific genes of caenophidian snakes are (pseudo)autosomal in the members of the snake families Pythonidae, Xenopeltidae, Boidae, Erycidae and Sanziniidae, as well as in outgroups with differentiated sex chromosomes such as monitor lizards, iguanas and chameleons. Along with iguanas, advanced snakes are therefore another example of ectothermic amniotes with a long-term stability of sex chromosomes comparable with endotherms. 相似文献
129.
130.