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981.
982.
Antoine Blanc Nicolas Tran-Khanh Dominic Filion Michael D Buschmann 《The journal of histochemistry and cytochemistry》2005,53(9):1171-1175
Tissue engineering of articular cartilage requires accurate imaging of the chondrocyte cytoskeleton. Past studies have applied various fixation and permeabilization protocols without optimization of parameters. In this study, we have examined procedures using glutaraldehyde and paraformaldehyde as fixatives and Triton X-100 and Octyl-POE as permeabilizing detergents. A four-color fluorescence confocal method was developed to simultaneously image actin, tubulin, vimentin, and the nucleus. We found optimal preservation and morphology of the chondrocyte cytoskeleton after simultaneous fixation and permeabilization with glutaraldehyde and Triton X-100. These images displayed less cellular shrinkage and higher-resolution filamentous structures than with paraformaldehyde or when permeabilization followed fixation. 相似文献
983.
Nicolas Chartrel Françoise Collin Yung-Sen Huang Maïté Montero Marie-Christine Tonon H. J. T. Goos Sylvie Dufour H. Vaudry 《Cell and tissue research》1998,293(2):235-243
Two molecular variants of gonadotropin-releasing hormone (GnRH) have been previously characterized in the brain of amphibians, i.e., mammalian GnRH (mGnRH) and chicken GnRH-II (cGnRH-II). The aim of the present study was to identify the molecular forms of gonadotropin-releasing hormone and to localize gonadotropin-releasing hormone-containing elements in the spinal cord of the frog Rana ridibunda using highly specific antisera against mGnRH and cGnRH-II. High-performance liquid chromatography (HPLC) analysis combined with radioimmunoassay (RIA) detection revealed that frog spinal cord extracts contained both mGnRH and cGnRH-II. Immunohistochemical labeling revealed that the frog spinal cord was devoid of GnRH-containing cell bodies. In contrast, numerous GnRH-immunoreactive fibers were observed throughout the entire length of the cord. mGnRH immunoreactivity was only detected in the rostral region of the cord and consisted of varicose processes located in the vicinity of the central canal. cGnRH-II-positive fibers were found throughout the spinal cord, the density of immunoreactive processes decreasing gradually toward the caudal region. Two main cGnRH-II-positive fiber tracts with a rostrocaudal orientation were observed: a relatively dense fiber bundle surrounding the central canal, and a more diffuse plexus in the white matter. In addition, short, varicose cGnRH-II-positive processes with a radial orientation were present throughout the gray matter. These fibers were particularly abundant ventromedially and formed a diffuse network that ramified laterally to end in the vicinity of motoneurons. Taken together, these data indicate that the frog spinal cord, like the frog brain, contains two forms of GnRH. The presence of numerous cGnRH-II-immunoreactive fibers in the ventral horn suggests that cGnRH-II may influence the activity of a subpopulation of motoneurons. 相似文献
984.
985.
The postnatal fall in fatty acid synthesis in the liver and brown fat of newborn rabbits is accompanied in both tissues by a decrease in the capacities of the enzymes of fatty acid synthesis and an apparent increase in the degree of inhibition of one or more of these enzymes. 相似文献
986.
Nicolas Brucato Veronica Fernandes Stéphane Mazières Pradiptajati Kusuma Murray P. Cox Joseph Wainaina Ng’ang’a Mohammed Omar Marie-Claude Simeone-Senelle Coralie Frassati Farida Alshamali Bertrand Fin Anne Boland Jean-Francois Deleuze Mark Stoneking Alexander Adelaar Alison Crowther Nicole Boivin Luisa Pereira François-Xavier Ricaut 《American journal of human genetics》2018,102(1):58-68
987.
Anthony Drecourt Joël Babdor Michael Dussiot Floriane Petit Nicolas Goudin Meriem Garfa-Traoré Florence Habarou Christine Bole-Feysot Patrick Nitschké Chris Ottolenghi Metodi D. Metodiev Valérie Serre Isabelle Desguerre Nathalie Boddaert Olivier Hermine Arnold Munnich Agnès Rötig 《American journal of human genetics》2018,102(2):266-277
988.
989.
Rabih El Osta Thierry Almont Catherine Diligent Nicolas Hubert Pascal Eschwège Jacques Hubert 《Andrologie》2016,26(1):2
For several decades, testosterone and its synthetic derivatives have been used with anabolic and androgenic purposes. These substances were first restricted to professional bodybuilders, but become more and more popular among recreational athletes. Up to date, 3,000,000 anabolic-androgenic steroids (AAS) users have been reported in the United States with an increasing prevalence, making AAS consumption a major public health growing concern. Infertility is defined by the WHO as the failure to achieve a clinical pregnancy after 12 months or more of regular unprotected sexual intercourse and a male factor is present in up to 50 % of all infertile couples. Several conditions may be related to male infertility.Substance abuse, including AAS, is commonly associated to transient or persistent impairment on male reproductive function, through different pathways. Herein, a brief overview on AAS is offered. Steroids biochemistry, patterns of use, physiological and clinical issues are enlightened. A further review about fertility outcomes among male AAS abusers is also presented, including the classic reports on transient anabolic steroid-induced hypogonadism (ASIH), and the more recent experimental reports on structural and genetic sperm damage. 相似文献
990.
Eric W.M. Stienen Peter Desmet Bart Aelterman Wouter Courtens Simon Feys Nicolas Vanermen Hilbran Verstraete Marc Van de Walle Klaas Deneudt Francisco Hernandez Robin Houthoofdt Bart Vanhoorne Willem Bouten Roland-Jan Buijs Marwa M. Kavelaars Wendt Müller David Herman Hans Matheve Alejandro Sotillo Luc Lens 《ZooKeys》2016,(555):115-124
In this data paper, Bird tracking - GPS tracking of Lesser Black-backed Gulls and Herring Gulls breeding at the southern North Sea coast is described, a species occurrence dataset published by the Research Institute for Nature and Forest (INBO). The dataset (version 5.5) contains close to 2.5 million occurrences, recorded by 101 GPS trackers mounted on 75 Lesser Black-backed Gulls and 26 Herring Gulls breeding at the Belgian and Dutch coast. The trackers were developed by the University of Amsterdam Bird Tracking System (UvA-BiTS, http://www.uva-bits.nl). These automatically record and transmit bird movements, which allows us and others to study their habitat use and migration behaviour in great detail. Our bird tracking network is operational since 2013. It is funded for LifeWatch by the Hercules Foundation and maintained in collaboration with UvA-BiTS and the Flanders Marine Institute (VLIZ). The recorded data are periodically released in bulk as open data (http://dataset.inbo.be/bird-tracking-gull-occurrences), and are also accessible through CartoDB and the Global Biodiversity Information Facility (GBIF). 相似文献