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91.
J. D. Anadón A. Giménez M. Martínez J. A. Palazón M. A. Esteve 《Diversity & distributions》2007,13(3):324-331
In this study we propose a model-building approach based on the hierarchical integration of the main environmental factors (climate, topography/lithology, and land uses) determining the distribution of the spur-thighed tortoise in south-east Spain. Data on the presence/absence of the species were primarily based on information derived from interviews to shepherds. The hierarchical modelling exercise consisted of three steps. First, we constructed a model for the entire region using climate variables, thus obtaining a potential climatical model. Second, we introduced variables referring to topography and lithology that fall within the climatic distribution range ( potential model). Third, by using this second model as a starting point, we included land use variables to obtain the actual distribution model.
We analysed the changes in the values of probability of the presence of this species for a given cell between the potential and the actual model, assessing areas where habitat quality has decreased, been maintained or increased. The spatial representation of these changes was highly coherent. A discriminant analysis linked areas where habitat quality has dropped with agriculture landscapes, whereas those areas where habitat quality has been maintained or increased were located mainly in shrublands. Twenty-five per cent (479 km2 ) of the potential distribution of the species became suboptimal when land use was included, which emphasizes the importance of land use changes in both the range dynamics and the conservation of the spur-thighed tortoise in south-east Spain. 相似文献
We analysed the changes in the values of probability of the presence of this species for a given cell between the potential and the actual model, assessing areas where habitat quality has decreased, been maintained or increased. The spatial representation of these changes was highly coherent. A discriminant analysis linked areas where habitat quality has dropped with agriculture landscapes, whereas those areas where habitat quality has been maintained or increased were located mainly in shrublands. Twenty-five per cent (479 km
92.
M R Padrós O Vindrola P Zunszain L Fainboin S Finkielman V E Nahmod 《Life sciences》1989,45(19):1805-1811
Several reports indicate that enkephalins participate in lymphocyte proliferation and several events of the immune response. It has been proposed that peptides involved in these processes may originate in the nervous system or endocrine glands. We have found that human peripheral blood lymphocytes (PBL) activated with a mitogenic agent contain and release proenkephalin derived peptides. The kinetics of met-enkephalin and cryptic products of proenkephalin in PBL activated with phytohemaglutinin (PHA) were studied. Peptides were released to the supernatant of stimulated PBL, reaching the highest values after 18 to 24 hours. The material secreted corresponds to high, intermediate and low molecular weight peptides derived from proenkephalin, displaying met-enkephalin and synenkephalin (proenkephalin 1-70) immunoreactivity. Therefore, an intrinsic lymphocytic proenkephalin system is induced by PHA and may play an important role in the regulation of the immune response. 相似文献
93.
94.
Maria A. Cerdá Esteve Diego Barral Tafalla Mindaugas Gudelis Albert Goday Magi Farre Albaladejo Juan F. Cano 《Endocrinología y nutrición》2010,57(4):155-159
ObjectiveTo establish the prevalence of psychoactive drug consumption in an obese population.Material and methodsWe collected data from the clinical records of obese patients attending the Endocrinology and Nutrition Department and Psychiatry Department of Hospital del Mar between June 2005 and May 2006 (n=259). We recorded anthropometric, epidemiological and toxicological data. We also investigated the prevalence of concomitant diseases in this population.ResultsPsychoactive drugs were consumed by 37% of obese patients, mainly antidepressants (27%), anxiolytics, sedatives and hypnotics, and anticonvulsants. Moreover, 15% of all patients received combination treatment with two or more psychoactive drugs, mostly the association of an antidepressant and an antiepileptic drug.ConclusionThe prevalence of psychoactive drug consumption in our sample was higher than prevalence data observed in the general population, with antidepressant consumption being three-fold higher. 相似文献
95.
Maria Dolores Arias Padrò Andrea Frattarelli Alessandra Sgueglia Emiliano Condello Carmine Damiano Emilia Caboni 《Plant Cell, Tissue and Organ Culture》2012,108(1):167-172
Shoot apices of in vitro-grown plantlets of white mulberry, Morus alba L. cv Florio, were cryopreserved using either encapsulation-dehydration or vitrification. For encapsulation-dehydration,
alginate beads containing apices were dehydrated for 1, 3, 5 or 7 days in a liquid medium containing various sucrose concentrations
(0.5, 0.75, 1.0 or 1.25 M). Bead desiccation was performed using silica gel for either 0, 4, 6, 8, 9 or 14 h. For vitrification,
apices were directly immersed for either 5, 15, 30 or 60 min in a vitrification solution (PVS2). Following encapsulation-dehydration,
treatment of alginate beads with 0.75 M sucrose was more effective in promoting re-growth of explants after immersion in liquid
nitrogen than in the presence of 0.5 M sucrose for either 1 or 3 days. Re-growth of explants was also observed following vitrification
and this reached 47% with increasing duration of the PVS2 treatment from 5 to 30 min. Overall, the highest frequency of explant
re-growth was obtained when explants were subjected to encapsulation-dehydration in the presence of 0.75 M along with a 3 day
sucrose dehydration pre-treatment and followed by desiccation for 9 h in silica gel. 相似文献
96.
J. D. Anadón A. Giménez I. Pérez M. Martínez M. A. Esteve 《Biodiversity and Conservation》2006,15(7):2287-2299
As a result of human activities, natural Mediterranean landscapes (including agro-ecosystems) are characterised by a mosaic-like
structure with habitat-patches at different successional stages. These systems have high biodiversity levels and are home
to a large number of species protected by European laws whose habitats should be adequately managed. In the present work,
we study habitat use from an applied point of view in the spur-thighed tortoise Testudo graeca, an endangered reptile present in semi-arid Mediterranean agro-ecosystems. Results show that, at a landscape scale, the species
selects simplified vegetation structures and includes in its home range re-colonisation shrubland and small non-irrigated
fields. Within the home range, habitat selection patterns vary and areas with higher vegetation cover and complexity are selected.
Detected patterns are discussed in terms of the ecological requirements of the species and with a hierarchical view of resources
and conditions. The implications of our findings for habitat management aimed at the conservation of the species are also
discussed. 相似文献
97.
Esteve C Nueda A Díaz JL Beleta J Cárdenas A Lozoya E Cadavid MI Loza MI Ryder H Vidal B 《Bioorganic & medicinal chemistry letters》2006,16(14):3642-3645
A new series of 4-(1,3-dialkyl-2,4-dioxo-2,3,4,5-tetrahydro-1H-pyrrolo[3,2-d]pyrimidin-6-yl)benzenesulfonamides has been identified as potent A2B adenosine receptor antagonists. The products have been evaluated for their binding affinities for the human A2B, A1 and A3 adenosine receptors. 6-(4-{[4-(4-Bromobenzyl)piperazin-1-yl]sulfonyl}phenyl)-1,3-dimethyl-1H-pyrrolo[3,2-d]pyrimidine-2,4(3H,5H)-dione (16) showed a high affinity for the A2B adenosine receptor (IC50=1 nM) and selectivity (A1: 183x; A3: 12660x). Synthesis and SAR of this novel class of compounds showing improved absorption properties is presented herein. 相似文献
98.
Carrillo R León LG Martín T Martín VS Padrón JM 《Bioorganic & medicinal chemistry letters》2006,16(23):6135-6138
In this study, we synthesized a series of enantiomerically pure (2R,3R)-disubstituted tetrahydropyrans with diverse functional groups. The in vitro antiproliferative activities were examined in the human solid tumor cell lines A2780 (ovarian cancer), SW1573 (non-small cell lung cancer), and WiDr (colon cancer). Overall, the results show the relevance for antiproliferative activity of the alpha,beta-unsaturated ester side chain at position 2 of the THP ring. 相似文献
99.
Beta'-hydroxy-alpha,beta-unsaturated ketones: a new pharmacophore for the design of anticancer drugs
Padrón JM Miranda PO Padrón JI Martín VS 《Bioorganic & medicinal chemistry letters》2006,16(8):2266-2269
A series of beta'-hydroxy-alpha,beta-unsaturated ketones were prepared by means of an iron(III) catalyzed domino process. The in vitro antiproliferative activities were examined in the human solid tumor cell lines A2780, SW1573, and WiDr. The results showed that beta'-hydroxy-alpha,beta-unsaturated ketones were more potent than alpha,beta-unsaturated ketones. The best activity profiles were obtained for the derivatives bearing cyclic or branched substituents on the side chains. 相似文献
100.