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71.
72.
Both male and female of a new species of Eriopeltasttes Burmeister & Schaum, 1840, E. (E.) ornatus Ricchiardi, sp. n., are described from the mistbelt grassland of KwaZulu-Natal. Sexual dimorphism is extreme in this genus, with females being brachypterous, fossorial and entirely black to dark brown in general body colour. This is only the fifth out of 12 known species in this genus for which the female is known. The species appears to be restricted to areas within or in the immediate vicinities of two marginal nature reserves, Karkloof and Blinkwater, in a grassland habitat that is regarded as one of the most threatened in the Province of KwaZulu-Natal. Despite its acknowledged importance as centre of endemism the area is currently in a precarious state of large-scale degradation. 相似文献
73.
Dawn Field Peter Sterk Renzo Kottmann J. Wim De Smet Linda Amaral-Zettler Guy Cochrane James R. Cole Neil Davies Peter Dawyndt George M. Garrity Jack A. Gilbert Frank Oliver Gl?ckner Lynette Hirschman Hans-Peter Klenk Rob Knight Nikos Kyrpides Folker Meyer Ilene Karsch-Mizrachi Norman Morrison Robert Robbins Inigo San Gil Susanna Sansone Lynn Schriml Tatiana Tatusova Dave Ussery Pelin Yilmaz Owen White John Wooley Gregory Caporaso 《Standards in genomic sciences》2014,9(3):599-601
74.
Alberta Ferrari Paolo Dionigi Francesca Rovera Luigi Boni Giorgio Limonta Silvana Garancini Diego De Palma Gianlorenzo Dionigi Cristiana Vanoli Mario Diurni Giulio Carcano Renzo Dionigi 《World journal of surgical oncology》2006,4(1):1-8
Extra-abdominal desmoid tumours are slow-growing, histologically benign tumours of fibroblastic origin with variable biologic behaviour. They are locally aggressive and invasive to surrounding anatomic structures. Magnetic resonance imaging is the modality of choice for the diagnosis and the evaluation of the tumours. Current management of desmoids involves a multidisciplinary approach. Wide margin surgical resection remains the main treatment modality for local control of the tumour. Amputation should not be the initial treatment, and function-preserving procedures should be the primary treatment goal. Adjuvant radiation therapy is recommended both for primary and recurrent lesions. Chemotherapy may be used for recurrent or unresectable disease. Overall local recurrence rates vary and depend on patient's age, tumour location and margins at resection. 相似文献
75.
Microbialites, bioaccretionary structures formed during the growth and metabolism of microorganisms (principally cyanobacteria) were the dominant lifeform in shallow late-Archean and Proterozoic oceans. During the Cambrian radiation of metazoan life, which began ~540 Mya, microbialite abundance and diversity further declined following a peak in the Mesoproterozoic. Notwithstanding contention, grazing and bioturbation effects of metazoans have been hypothesized as the dominant driver of modern microbialite scarcity. However, this metazoan–microbialite exclusion has not been fully explored in the few extant microbialites. Here we provide further evidence showing that living marine layered microbialites (stromatolites) coexist with a persistent assemblage of benthic macro-invertebrates, as has previously been demonstrated in some thrombolitic (clotted) microbialites. Surprisingly, these metazoans have active habits, such as burrowing, which should be expected to disrupt the layered matrix. As other studies have shown, through a network of burrows, metazoans can exploit local diurnal oxygen refugia within microbialites as well as escape predation. Our results, therefore, add novel evidence in support of the hypotheses that geologically, metazoans are not always incompatible with stromatolites, while ecologically, microbialites may act as micro-refugia for modern metazoans and historically have performed a similar inferred role in past ecosystems. 相似文献
76.
S Amoroso M Taglialatela L M Canzoniero E J Cragoe G di Renzo L Annunziato 《Life sciences》1990,46(12):885-894
Insulin (63 microM) stimulated endogenous dopamine (DA) release from tuberoinfundibular neurons. This effect was independent on the presence of extracellular glucose and did not involve the outward transport of DA, mediated by its membrane carrier. By contrast this effect was completely prevented by the removal of extracellular Ca++ ions in presence of the Ca(++)-chelator ethyleneglycol-2-(2-aminoethyl)-tetracetic acid (EGTA). Furthermore 1-(5-isoquinolinyl-sulfonyl)-2-methyl-piperazine (H7), a compound which behaves as a putative inhibitor of protein kinase C (PK-C) (10 microM), completely counteracted the stimulation of endogenous DA release induced by insulin. Amiloride (300 microM) and its 5-amino nitrogen atom-substituted derivative, 5-(N-methyl-N-(guanidinocarbonylmethyl) amiloride (MGCMA) (10 microM), a highly selective inhibitor of the Na(+)-H+ membrane antiporter, were both able to prevent the stimulatory action exerted by insulin on endogenous DA release. Collectively, these results suggest that the transductional events by which insulin stimulated endogenous DA release from TIDA neurons may involve the activation of PK-C, the enhancement of Ca++ influx and the stimulation of the Na(+)-H+ exchange system. 相似文献
77.
Platelet-activating factor metabolism in human amnion and the responses of this tissue to extracellular platelet-activating factor 总被引:1,自引:0,他引:1
M M Billah G C Di Renzo C Ban C T Truong D R Hoffman M M Anceschi J E Bleasdale J M Johnston 《Prostaglandins》1985,30(5):841-850
It was found previously that platelet-activating factor (PAF, 1-0-alkyl-2-acetyl-sn-glycero-3-phosphocholine) is undetectable in human amniotic fluid obtained before labor but is present in the majority of samples of amniotic fluid obtained after labor. In the present investigation, the amount of PAF in amnion tissue and the ability of this tissue to produce PAF and respond to PAF were investigated. Amounts of PAF in amnion obtained either during the second trimester of gestation or at term (before labor) were similar. After labor, however, the amount of PAF in amnion increased to 2.5-times that in amnion before labor without any discernible changes in the amounts of two related glycerophospholipids viz., 1-0-alkyl-sn-glycero-3-phosphocholine and 1-0-alkyl-2-acyl-sn-glycero-3-phosphocholine. The Ca2+-ionophore A23187, in the presence of Ca2+, caused an increase in the amount of PAF in amnion tissue disks but PAF did not appear to be released into the incubation medium. The stimulation of PAF formation by A23187 and Ca2+ was not affected by the addition of indomethacin. Addition of PAF to disks of amnion tissue resulted in an increase in the concentration of prostaglandin E2 in the incubation medium. An increase in prostaglandin E2 formation of similar magnitude was induced by A23187. Based on these results it is concluded that PAF can be synthesized in amnion tissue and net production is stimulated by Ca2+. In addition, amnion is receptive to extracellular PAF and exhibits, as one response, an increased production of prostaglandin E2. 相似文献
78.
Francesco Maria Sabatini Sabina Burrascano William S. Keeton Christian Levers Marcus Lindner Florian Pötzschner Pieter Johannes Verkerk Jürgen Bauhus Erik Buchwald Oleh Chaskovsky Nicolas Debaive Ferenc Horváth Matteo Garbarino Nikolaos Grigoriadis Fabio Lombardi Inês Marques Duarte Peter Meyer Rein Midteng Stjepan Mikac Martin Mikoláš Renzo Motta Gintautas Mozgeris Leónia Nunes Momchil Panayotov Peter Ódor Alejandro Ruete Bojan Simovski Jonas Stillhard Miroslav Svoboda Jerzy Szwagrzyk Olli‐Pekka Tikkanen Roman Volosyanchuk Tomas Vrska Tzvetan Zlatanov Tobias Kuemmerle 《Diversity & distributions》2018,24(10):1426-1439
Aim
Primary forests have high conservation value but are rare in Europe due to historic land use. Yet many primary forest patches remain unmapped, and it is unclear to what extent they are effectively protected. Our aim was to (1) compile the most comprehensive European‐scale map of currently known primary forests, (2) analyse the spatial determinants characterizing their location and (3) locate areas where so far unmapped primary forests likely occur.Location
Europe.Methods
We aggregated data from a literature review, online questionnaires and 32 datasets of primary forests. We used boosted regression trees to explore which biophysical, socio‐economic and forest‐related variables explain the current distribution of primary forests. Finally, we predicted and mapped the relative likelihood of primary forest occurrence at a 1‐km resolution across Europe.Results
Data on primary forests were frequently incomplete or inconsistent among countries. Known primary forests covered 1.4 Mha in 32 countries (0.7% of Europe’s forest area). Most of these forests were protected (89%), but only 46% of them strictly. Primary forests mostly occurred in mountain and boreal areas and were unevenly distributed across countries, biogeographical regions and forest types. Unmapped primary forests likely occur in the least accessible and populated areas, where forests cover a greater share of land, but wood demand historically has been low.Main conclusions
Despite their outstanding conservation value, primary forests are rare and their current distribution is the result of centuries of land use and forest management. The conservation outlook for primary forests is uncertain as many are not strictly protected and most are small and fragmented, making them prone to extinction debt and human disturbance. Predicting where unmapped primary forests likely occur could guide conservation efforts, especially in Eastern Europe where large areas of primary forest still exist but are being lost at an alarming pace. 相似文献79.
80.
New piperidine-based derivatives as sigma receptor ligands. Synthesis and pharmacological evaluation
Daniele Zampieri Maurizio Romano Renzo Menegazzi Maria Grazia Mamolo 《Bioorganic & medicinal chemistry letters》2018,28(19):3206-3209
The sigma receptor (σR) family has been considered mysterious for a long time. In fact, the σ2R subtype has been cloned only recently, revealing its identity as TMEM97, a NPC1-binding protein involved in cholesterol biosynthesis and implicated in the pathogenesis of cancer and neurologic disorders. With the aim of developing new chemical entities gifted with σR affinity, herein we report the design and synthesis of new piperidine-based alkylacetamide derivatives with mixed affinity towards both σ1 and σ2R subtypes. 相似文献