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R. Laurà F. Abbate G. P. Germanà G. Montalbano A. Germanà M. Levanti 《Anatomia, histologia, embryologia》2018,47(4):322-329
The mechanosensory lateral line system of fish is responsible for several functions such as balance, hearing, and orientation in water flow and is formed by neuromast receptor organs distributed on head, trunk and tail. Superficial and canal neuromasts can be distinguished for localization and morphological differences. Several information is present regarding the superficial neuromasts of zebrafish and other teleosts especially during larval and juvenile stages, while not as numerous data are so far available about the ultrastructural characteristics of the canal neuromasts in adult zebrafish. Therefore, the aim of this study was to investigate by transmission electron microscopy the ultrastructural aspects of cells present in the canal neuromasts. Besides the typical cellular aspects of the neuromast, different cellular types of hair cells were observed that could be identified as developing hair cells during the physiological turnover. The knowledge of the observed cellular types of the canal neuromasts and their origin could give a contribution to studies carried out on adult zebrafish used as model in neurological and non‐neurological damages, such as deafness and vestibular disorders. 相似文献
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Mari Lappalainen Marjo Palviainen Jussi V.K. Kukkonen Heikki Setälä Sirpa Piirainen Tytti Sarjala Harri Koivusalo Leena Finér Samuli Launiainen Ari Laurén 《Water, air, and soil pollution》2018,229(7):240
Terrestrial export of dissolved organic carbon (DOC) to watercourses has increased in boreal zone. Effect of decomposing material and soil food webs on the release rate and quality of DOC are poorly known. We quantified carbon (C) release in CO2, and DOC in different molecular weights from the most common organic soils in boreal zone; and explored the effect of soil type and enchytraeid worms on the release rates. Two types of mor and four types of peat were incubated in laboratory with and without enchytraeid worms for 154 days at +?15 °C. Carbon was mostly released as CO2; DOC contributed to 2–9% of C release. The share of DOC was higher in peat than in mor. The release rate of CO2 was three times higher in mor than in highly decomposed peat. Enchytraeids enhanced the release of CO2 by 31–43% and of DOC by 46–77% in mor. High molecular weight fraction dominated the DOC release. Upscaling the laboratory results into catchment level allowed us to conclude that peatlands are the main source of DOC, low molecular weight DOC originates close to watercourse, and that enchytraeids substantially influence DOC leaching to watercourse and ultimately to aquatic CO2 emissions. 相似文献
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Laurène?FeintrenieEmail author Wan?Kian?Chong Patrice?Levang 《Small-Scale Forestry》2010,9(3):379-396
Indonesia has been the world’s largest producer and exporter of palm oil since 2008. This paper discussed the livelihood impacts
of oil palm development in Indonesia, based on lessons learnt from Bungo district, in the province of Jambi. The various community-company
partnerships that structure the sector are reviewed and the difficulties raised by the joint ventures schemes are discussed.
The merits and drawbacks of oil palm as a smallholder crop are then analysed, based on household socio-economic surveys conducted
in 2007–2010. The main causes of conflicts between oil palm companies and communities are unclear land tenure, and a recurrent
lack of leadership in smallholders’ cooperatives. Under fair partnerships between smallholders and companies, oil palm could
become a smallholder friendly crop. The land-use profitability analysis demonstrates the high returns that can be generated
by oil palm independent smallholdings, making it highly competitive with rubber, and much more profitable than rice production. 相似文献
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Francesco Abbate Maria Cristina Guerrera Maria Levanti Rosaria Laurà Germana Patrizia Germanà Giuseppe Montalbano Mauro Cavallaro Antonino Germanà 《Anatomia, histologia, embryologia》2020,49(6):686-694
The Atlantic salmon (Salmo salar) is a freshwater and marine fish of the family Salmonidae, widely farmed in aquaculture facilities in several countries. The salmon are carnivorous, but in aquaculture, alternative foods have been experienced. It is well known that feeding in captivity should cause adaptation and modifications of the morphological characteristics of the oral cavity, especially of tongue; therefore, the aim of this study was to investigate, by light, laser confocal and scanning electron microscopy, the morphological characteristics of the tongue dorsal surface, considering the importance of the correlations between feeding habits and the anatomy of the tongue. Scanning electron microscopy demonstrates the presence of caniniform teeth with oro-aboral orientation surrounded by numerous filiform papillae, single, fused or arranged in row. Oro-aborally, the papillae show an appearance like a rosette and they disappear at level of the root. Light and laser confocal microscopy demonstrates that the mucosa is covered by a non-keratinized stratified pavement epithelium with, in the deepest layer, the presence of a triangular structure whose apex is cranially directed and base facing aborally. In this structure, spindle-shaped cells are present, with a vimentin immunoreactivity, that for their characteristics could be adult mesenchymal stem cells. The obtained data could be useful not only for further studies on the nutrition, but it is interesting the detection of tissues typical of the embryo-fetal phase in the adult specimens tongue, thus giving a basis for studies of potential applications, if any, regarding cell therapies for different clinical indications. 相似文献
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Presence and distribution of leptin and its receptor in the gut of adult zebrafish in response to feeding and fasting 
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下载免费PDF全文 Olivia Garcia‐Suarez Roberto Cabo Francesco Abbate Basilio Randazzo Rosaria Laurà Giuseppe Piccione Antonino Germanà Maria Levanti 《Anatomia, histologia, embryologia》2018,47(5):456-465
Leptin is an anorectic hormone secreted mainly by peripheral adipocytes but also by other central and peripheral tissues. It acts by means of a receptor called OB‐R, influencing not only appetite and body mass but being also involved in many fields like endocrinology, metabolism and reproduction. Immunohistochemistry and qRT‐PCR techniques were, respectively, used to demonstrate the presence of leptin and its receptor in the gut of adult zebrafish and to evaluate the leptin gene expression response to feeding and fasting. Immunoreactivity for the antibodies utilized was demonstrated in feeding but not in fasting fish, and the gene expression analysis corroborates the data obtained by immunohistochemistry. Therefore, all the obtained results support the hypothesis of the role of this hormone in food regulation in zebrafish. 相似文献
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Carlo Poltronieri Rosaria Laurà Daniela Bertotto Elena Negrato Claudia Simontacchi Maria Cristina Guerrera Giuseppe Radaelli 《Veterinary research communications》2009,33(7):619-629
Farmed fish are usually exposed to routine procedures which have strong effects on stress responses. Rodlet cells may represent
an useful biomarker for studies on the presence of stressors in aquaculture. This work focused on the localization of rodlet
cells by light and electron microscopy in gills of sea bass (Dicentrarchus labrax) subjected to different conditions of overcrowding. In general, a significant increase in number of rodlet cells has been
observed in all animals subjected to overcrowding stress. In gills of control group rare rodlet cells were detected at the
level of both primary and secondary lamellae, whereas in stressed group clusters of rodlet cells have been found in the epithelium
of primary and secondary lamellae indicating that these cells are influenced by stocking density. 相似文献
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Coconut-based agroforestry systems have a central role in livelihoods on Malo Island in the South Pacific. These mixed plantations
provide households with both food and a cash income, thanks to the association in space and time of root crops, vegetables,
and cash crops (coconut, cocoa and vanilla). Vanilla has been developed on the island since the year 2000. Farmers have tried
to adapt their production systems to include it, with some choosing to do so by associating vanilla with their main cash crop,
coconut. A survey of these innovative practices and their economic results conducted in 2005 resulted in an economic modelling
of this new agroforestry system with the software Olympe. This study illustrates the use of economic modelling with Olympe
to simulate and test new agricultural practices in complex agroforestry systems. The software proved to suit agroforestry
systems very well and provided useful information, particularly on economic aspects. 相似文献
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Francesco Abbate Maria Cristina Guerrera Maria Levanti Rosaria Laurà Giuseppe Montalbano Mauro Cavallaro Antonino Germanà 《Anatomia, histologia, embryologia》2020,49(1):51-59
The leopard gecko is a crepuscular and insectivorous reptile. The role of the tongue in this reptile is fundamental for the prey capture and ingestion and is not related with eyes cleaning as usual in other geckos. The elongated tongue can be divided into a foretongue with a slightly bifurcated apex and a hindtongue. Scanning electron microscopy demonstrated that several different papillae are present on the dorsal surface, foliate and dome-shaped in the foretongue, becoming thicker and stouter with reduced interpapillary spaces in the lateral parts. The hindtongue is characterised by wide foliate papillae with indented margins and deep fissures of the mucosa. Light microscopy showed the presence of a stratified slightly keratinized squamous epithelium in the apex of the foretongue, a stratified non-keratinized squamous epithelium in the fore and in the hindtongue. In the foretongue, numerous muciparous caliciform cells were observed. Moreover, the presence of taste buds on the tongue ventral surface was demonstrated for the first time in this species and the confocal laser study revealed a strong immunoreactivity for the S-100 protein in the sensory cells. Therefore, the results obtained could give a contribution to the knowledge of the tongue anatomy and are a basis for eventual further studies regarding the feeding habits in a reptile become a popular pet. 相似文献