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111.
Fatima El-Houaria Zitouni-Haouar Pablo Alvarado Imed Sbissi Abdellatif Boudabous Zohra Fortas Gabriel Moreno José Luis Manjón Maher Gtari 《PloS one》2015,10(9)
The species concept within the genus Picoa Vittad. is here revisited in light of new molecular and ecological data obtained from samples collected throughout the Mediterranean basin. Two highly diverse widespread clades and four additional minor lineages were significantly supported by three genes dataset (ITS, 28s LSU and RPB2) inferences for 70 specimens. The two widespread clades occur in very different geographical and ecological areas associated with exclusive host plants in the genus Helianthemum. SEM study of spore surface morphology in these lineages revealed the existence of smooth ascospores in the majority of these clades. However the most frequent lineage in Europe and coastal North Africa displayed either smooth or verrucose spores. Hence this morphological criterion cannot be reliably used to discriminate between the different clades. In addition, SEM observations made on ascospores from several original collections of P. juniperi and P. lefebvrei supported the hypothesis that ornamentation depends on the degree of maturity in some of these lineages. Geographical and ecological, rather than morphological data are here suggested as the most useful characters to separate the different lineages in Picoa. Further studies focusing on these features are needed before the names P. juniperi and P. lefebvrei can be unambiguously linked with the genetic lineages observed. 相似文献
112.
Background
The statistical modeling of biomedical corpora could yield integrated, coarse-to-fine views of biological phenomena that complement discoveries made from analysis of molecular sequence and profiling data. Here, the potential of such modeling is demonstrated by examining the 5,225 free-text items in the Caenorhabditis Genetic Center (CGC) Bibliography using techniques from statistical information retrieval. Items in the CGC biomedical text corpus were modeled using the Latent Dirichlet Allocation (LDA) model. LDA is a hierarchical Bayesian model which represents a document as a random mixture over latent topics; each topic is characterized by a distribution over words. 相似文献113.
114.
SMM?VerstappenEmail author AR?Poole M?Ionescu LE?King M?Abrahamowicz DM?Hofman JWJ?Bijlsma FPJG?Lafeber the Utrecht Rheumatoid Arthritis Cohort Study group 《Arthritis research & therapy》2005,8(1):R31
Introduction
The objective of this study was to determine whether serum biomarkers for degradation and synthesis of the extracellular matrix of cartilage are associated with, and can predict, radiographic damage in patients with rheumatoid arthritis (RA). 相似文献115.
116.
Peripheral blood and tissue from twenty-two free-ranging, hunter-killed capybaras (Hydrochaeris hydrochaeris) collected between December 1996 and April 1997 in Casanare, Colombia (5 degrees 58'N and 71 degrees 33'W), were examined by light microscopy for Kurloff cells (KCs). Kurloff cells were observed in the blood of one pregnant adult female, and in organs from all the animals, including spleen (21 of 22 animals), liver (18 of 21), lungs (13 of 21), ovary (8 of 11), uterus (7 of 10), bone marrow (13 of 20), kidney (8 of 22), adrenal gland (6 of 20), and lymph node (4 of 14). The anatomic distribution of the KC in the wild capybaras was similar to that of the guinea pig. 相似文献
117.
Multicellularity, stem cells, and the neoblasts of the planarian Schmidtea mediterranea 总被引:1,自引:0,他引:1
All multicellular organisms depend on stem cells for their survival and perpetuation. Their central role in reproductive, embryonic, and post-embryonic processes, combined with their wide phylogenetic distribution in both the plant and animal kingdoms intimates that the emergence of stem cells may have been a prerequisite in the evolution of multicellular organisms. We present an evolutionary perspective on stem cells and extend this view to ascertain the value of current comparative studies on various invertebrate and vertebrate somatic and germ line stem cells. We suggest that somatic stem cells may be ancestral, with germ line stem cells being derived later in the evolution of multicellular organisms. We also propose that current studies of stem cell biology are likely to benefit from studying the somatic stem cells of simple metazoans. Here, we present the merits of neoblasts, a largely unexplored, yet experimentally accessible population of stem cells found in the planarian Schmidtea mediterranea. We introduce what we know about the neoblasts, and posit some of the questions that will need to be addressed in order to better resolve the relationship between planarian somatic stem cells and those found in other organisms, including humans. 相似文献
118.
Synthesis and binding affinity of novel 3-aminoethyl-1-tetralones, potential atypical antipsychotics
Alvarado M Coelho A Masaguer CF Raviña E Brea J Padín JF Loza MI 《Bioorganic & medicinal chemistry letters》2005,15(12):3063-3066
A series of 3-aminoethyl-1-tetralones, conformationally constrained higher homologues of haloperidol (standard for typical antipsychotic profile), have been obtained by a four-step route from valerolactone. Their binding affinities at dopamine D(2) and serotonin 5-HT2A and 5-HT2C receptors were determined, showing in some cases an atypical antipsychotic profile. 相似文献
119.
A total of 25 species of echinoderms (four asteroids, six ophiuroids, five echinoids and ten holothurians) were recorded at Marino Ballena National Park, using 25 m2 quadrants, parallel to the coast, at seven sites. The ophiuroids were the most abundant group with 581 individuals and the asteroids the less abundant (48 individuals). Echinoderms densities were low, with the exception of the ophiuroids. Diversity, density and the number of groups were higher where sedimentation was lower. We suggest that sedimentation is having a negative effect on the diversity of echinoderms and on the development of the coral reefs in this park. 相似文献
120.