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741.
Surface-spread spermatocytes of the fallow deer were examined by light microscopy after silver staining. The development and behaviour of synaptonemal complexes and the partial synapsis of the X and Y chromosomes were investigated during leptotene to diplotene chromosome pairing. 相似文献
742.
Gualtiero Basilone Rosalia Ferreri Salvatore Mangano Maurizio Pulizzi Antonella Gargano Marco Barra Salvatore Mazzola Ignazio Fontana Giovanni Giacalone Simona Genovese Salvatore Aronica Angelo Bonanno 《Hydrobiologia》2018,812(1):99-114
Species distributions are structured by regional and local determinants, which operate at multiple spatial and temporal scales. The purpose of our work was to distinguish the relative roles of local variables, climate, geographical location and post glaciation condition (i.e., delineation between supra- and subaquatic lakes during the post-glacial Ancylus Lake) in explaining variation in macrophyte community composition of all taxa, helophytes and hydrophytes. In addition, we investigated how these four explanatory variable groups affected macrophyte strategy groups based on Grime’s classification. Using partial linear regression and variation partitioning, we found that macrophyte communities are primarily filtered by local determinants together with regional characteristics at the studied spatial scale. We further evidenced that post glaciation condition indirectly influenced on local water quality variables, which in turn directly contributed to the macrophyte communities. We thus suggest that regional determinants interact with local-scale abiotic factors in explaining macrophyte community patterns and examining only regional or local factors is not sufficient for understanding how aquatic macrophyte communities are structured locally and regionally. 相似文献
743.
M. Maraschin J.A. Sugui K.V. Wood C. Bonham F.M. Lanças P.S. Araujo R.A. Yunes R. Verpoorte J.D. Fontana 《Biotechnology letters》2001,23(1):77-82
MALDI-TOF MS analysis of supercritical CO2 extracted samples obtained from Mandevilla velutina cell cultures allowed the detection of the anti-bradykinin pregnanic steroid, velutinol A, using low amount of sample (1 g lyophilized cells), with minimum analyte isolation. 相似文献
744.
745.
Francesco Fontana 《Chromosoma》1980,81(2):169-175
In six Italian populations of the rhinotermitid Reticulitermes lucifugus there is a diploid complement of 2n=42 with no visible sex chromosome difference between male and female reproductives. The first male meiotic division in this species is, however, characterised by the presence of inter-change multiples. Thus males from three mainland colonies at Udine, Tombolo and Barberino, as well as a Sicilian colony (Polizzi), are regularly heterozygous for a single translocation chain (C) multiple of IV (2n=19II+ C IV). A fourth mainland colony (Squinzano) proved to be polymorphic. Here, three of the six males analysed regularly formed 21 bivalents; two further males had nineteen bivalents and a chain of four multiple while a sixth male had a predominance of meiocytes with 19 bivalents and a chain of four together with a small number of cells with 18 bivalents and a chain of six multiple. Finally a sixth colony from Sardinia (Sennori) was characterized by larger multiple configurations involving chains or rings of eight. 相似文献
746.
The Gravlee endometrial jet wash technique has been used to collect uterine fluid in normal human volunteers for Prostaglandin F analysis throughout the human menstrual cycle. Uterine washings so obtained demonstrated a cyclicity in prostaglandin F content with low concentrations found during the proliferative phase and a 3-4 fold rise occurring during the secretory phase. Menstrual fluid prostaglandin F content collected with the jet wash technique gave the highest total concentrations. 相似文献
747.
Simona Fontana Odessa Schillaci Monica Frinchi Marco Giallombardo Giuseppe Morici Valentina?Di Liberto Riccardo Alessandro Giacomo De Leo Vincenzo Perciavalle Natale Belluardo Giuseppa Mudò 《Bioscience reports》2015,35(3)
In our recent study was shown a significant recovery of damaged skeletal muscle of mice with X-linked muscular dystrophy (mdx) following low-intensity endurance exercise, probably by reducing the degeneration of dystrophic muscle. Consequently, in the present work, we aimed to identify proteins involved in the observed reduction in degenerating fibres. To this end, we used proteomic analysis to evaluate changes in the protein profile of quadriceps dystrophic muscles of exercised compared with sedentary mdx mice. Four protein spots were found to be significantly changed and were identified as three isoforms of carbonic anhydrase 3 (CA3) and superoxide dismutase [Cu-Zn] (SODC). Protein levels of CA3 isoforms were significantly up-regulated in quadriceps of sedentary mdx mice and were completely restored to wild–type (WT) mice values, both sedentary and exercised, in quadriceps of exercised mdx mice. Protein levels of SODC were down-regulated in quadriceps of sedentary mdx mice and were significantly restored to WT mice values, both sedentary and exercised, in quadriceps of exercised mdx mice. Western blot data were in agreement with those obtained using proteomic analysis and revealed the presence of one more CA3 isoform that was significantly changed. Based on data found in the present study, it seems that low-intensity endurance exercise may in part contribute to reduce cell degeneration process in mdx muscles, by counteracting oxidative stress. 相似文献
748.
749.
Karina Fontana Fernanda M. Almeida Tatiana Carla Tomiosso Edson Rosa Pimentel Maria Alice da Cruz Höfling 《Cell and tissue research》2010,339(2):411-420
The effect of mesterolone and intensive treadmill training (6 weeks, 5 days/week, means: 15.82 m/min and 45.8 min/day) in Achilles tendon remodeling was evaluated. Sedentary mice treated with mesterolone (Sed-M) or vehicle (Sed-C, placebo/control) and corresponding exercised (Ex-M and Ex-C) were examined. SDS-polyacrylamide gel electrophoresis was used for determining collagen bands and hydroxyproline concentration. Collagen fibril diameter, the area and number of fibrils contained in an area probe, and the ultrastructure of fibroblasts (tenocytes) were determined. The presence of collagen was notable in the tendons of all groups. Collagen α1/α2 bands in Sed-M, Ex-C, and Ex-M were higher than in Sed-C, as shown by hydroxyproline content, but collagen β-chain appeared only in Ex-C. Noticeable bands of non-collagenous proteins were found in Sed-M and Ex-M. The number of fibrils in the area probe increased markedly in Sed-M and Ex-C (12-fold), but their diameter and area were unchanged compared with Sed-C. In Ex-M, the fibril number decreased by three–fold to 3.5-fold compared with Sed-M and Ex-C, whereas diameter and area increased. Sed-C tenocytes appeared quiescent, whereas those in the other groups seemed to be engaged in protein synthesis. The density of tenocytes was smaller in Sed-C than in Ex-C, Sed-M, and Ex-M. Thus, mechanical stimuli and mesterolone alter the morphology of tenocytes and the composition of the tendon, probably through fibrillogenesis and/or increased intermolecular cross-links. The ergogenic effect is evidenced by the activation of collagenous and non-collagenous protein synthesis and the increase in the diameter and area of collagen fibrils. This study might be relevant to clinical sports medicine. 相似文献
750.
Lorenzo Zane Tomaso Patarnello Arne Ludwig Francesco Fontana Leonardo Congiu 《Molecular ecology resources》2002,2(4):586-588
We isolated and characterized seven polymorphic microsatellite loci from a partial genomic library of the Adriatic sturgeon (Acipenser naccarii) enriched for GATA repeats. Variability was tested in 20 specimens of this endangered species. Our data support the tetraploid condition for A. naccarii and will be useful for the investigation of the remnant genetic variability of this species as well as for genetic tagging studies. 相似文献