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排序方式: 共有289条查询结果,搜索用时 15 毫秒
61.
62.
Lazaro E. Aira Patricia Hernández Dinorah Prada Araceli Chico Jorge A. Gómez Zuyén González 《MABS-AUSTIN》2016,8(1):187-195
Rheumatoid arthritis is an autoimmune disease characterized by joint inflammation that affects approximately 1% of the general population. Itolizumab, a monoclonal antibody specific for the human CD6 molecule mainly expressed on T lymphocytes, has been shown to inhibit proliferation of T cells and proinflammatory cytokine production in psoriasis patients. We have now assessed the immunological effect of itolizumab in combination with methotrexate in rheumatoid arthritis by analyzing clinical samples taken from 30 patients enrolled in a clinical trial. T and B cell subpopulations were measured at different time points of the study. Plasma cytokine levels and anti-idiotypic antibody response to itolizumab were also evaluated. The combined treatment of itolizumab and methotrexate led to a reduction in the frequency of T cell subpopulations, and plasma levels of proinflammatory cytokines showed a significant decrease up to at least 12 weeks after treatment ended. No anti-idiotypic antibody response was detected. These results support the relevance of the CD6 molecule as a therapeutic target for the treatment of this disease. 相似文献
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64.
Blanca Montalbán Sarah Croes Nele Weyens M Carmen Lobo Araceli Pérez-Sanz Jaco Vangronsveld 《International journal of phytoremediation》2016,18(10):985-993
The interaction between plant growth-promoting bacteria (PGPB) and plants can enhance biomass production and metal tolerance of the host plants. This work aimed at isolating and characterizing the cultivable bacterial community associated with Brassica napus growing on a Zn-contaminated site, for selecting cultivable PGPB that might enhance biomass production and metal tolerance of energy crops. The effects of some of these bacterial strains on root growth of B. napus exposed to increasing Zn and Cd concentrations were assessed. A total of 426 morphologically different bacterial strains were isolated from the soil, the rhizosphere, and the roots and stems of B. napus. The diversity of the isolated bacterial populations was similar in rhizosphere and roots, but lower in soil and stem compartments. Burkoholderia, Alcaligenes, Agrococcus, Polaromonas, Stenotrophomonas, Serratia, Microbacterium, and Caulobacter were found as root endophytes exclusively. The inoculation of seeds with Pseudomonas sp. strains 228 and 256, and Serratia sp. strain 246 facilitated the root development of B. napus at 1,000 µM Zn. Arthrobacter sp. strain 222, Serratia sp. strain 246, and Pseudomonas sp. 228 and 262 increased the root length at 300 µM Cd. 相似文献
65.
Claudia I. Echeverría Dora M. Isolabella Elio A. Prieto Gonzalez Araceli Leonardelli Laura Prada Alina Perrone Alicia G. Fuchs 《In vitro cellular & developmental biology. Animal》2010,46(9):781-792
The taeniid tapeworm Echinococcus granulosus is the causative agent of echinococcal disease, a major zoonosis with worldwide distribution. Several efforts to establish
an in vitro model of E. granulosus have been undertaken; however, many of them have been designed for Echinococcus multilocularis. In the present study, we have described and characterized a stable cell line obtained from E. granulosus bovine protoscoleces maintained 3 yr in vitro. Growth characterization, morphology by light, fluorescent and electronic microscopy,
and karyotyping were carried out. Cell culture origin was confirmed by immunofluorescent detection of AgB4 antigen and by PCR for the mitochondrial cytochrome c-oxidase subunit 1 (DCO1) gene. Cells seeded in agarose biphasic culture
resembled a cystic structure, similar to the one formed in secondary hosts. This cell line could be a useful tool to research
equinococcal behavior, allowing additional physiological and pharmacological studies, such as the effect of growth factors,
nutrients, and antiparasitic drugs on cell viability and growth and on cyst formation. 相似文献
66.
Clemens Küpper Scott V. Edwards András Kosztolányi Monif Alrashidi Terry Burke Philipp Herrmann Araceli Argüelles‐Tico Juan A. Amat Mohamed Amezian Afonso Rocha Hermann Hötker Anton Ivanov Joseph Chernicko Tamás Székely 《Molecular ecology》2012,21(23):5864-5879
Gene flow promotes genetic homogeneity of species in time and space. Gene flow can be modulated by sex‐biased dispersal that links population genetics to mating systems. We investigated the phylogeography of the widely distributed Kentish plover Charadrius alexandrinus. This small shorebird has a large breeding range spanning from Western Europe to Japan and exhibits an unusually flexible mating system with high female breeding dispersal. We analysed genetic structure and gene flow using a 427‐bp fragment of the mitochondrial (mtDNA) control region, 21 autosomal microsatellite markers and a Z microsatellite marker in 397 unrelated individuals from 21 locations. We found no structure or isolation‐by‐distance over the continental range. However, island populations had low genetic diversity and were moderately differentiated from mainland locations. Genetic differentiation based on autosomal markers was positively correlated with distance between mainland and each island. Comparisons of uniparentally and biparentally inherited markers were consistent with female‐biased gene flow. Maternally inherited mtDNA was less structured, whereas the Z‐chromosomal marker was more structured than autosomal microsatellites. Adult males were more related than females within genetic clusters. Taken together, our results suggest a prominent role for polyandrous females in maintaining genetic homogeneity across large geographic distances. 相似文献
67.
Ricardo Carreño-López Araceli Sánchez Nohemí Camargo Claudine Elmerich Beatriz Eugenia Baca 《Archives of microbiology》2009,191(6):501-507
We report, here, the characterization of a mutant strain of Azospirillum brasilense Sp7 impaired in surface motility and chemotactic response. Presence of flagella in the mutant strain was confirmed by western
blot analysis, using antisera raised against the polar and lateral flagellins, and by electron microscopy. Genetic complementation
and nucleotide sequencing led to the identification of a new gene, named chsA. The deduced translation product, ChsA protein, contained a PAS sensory domain and an EAL domain. As ChsA displayed characteristic
signaling protein architecture, it is thought that this protein is a component of the signaling pathway controlling chemotaxis
in Azospirillum. 相似文献
68.
The chile of Mesoamerica, Capsicum annuum, is one of five domesticated chiles in the Americas. Among the chiles, it varies the most in size, form, and color of its fruits. Together with maize, C. annuum is one of the principal elements of the neotropical diets of Mesoamerican civilizations. Despite the great economic and cultural importance of C. annuum both worldwide and in Mexico, however, very little is known about its geographic origin and number of domestications. Here we sampled a total of 80 accessions from Mexico (58 semiwild and 22 domesticated) and examined nucleotide sequence diversity at three single- or low-copy nuclear loci, Dhn, G3pdh, and Waxy. Across the three loci, we found an average reduction of ca. 10% in the diversity of domesticates relative to semiwild chiles and geographic structure within Mexican populations. The Yucatan Peninsula contained a large number of haplotypes, many of which were unique, suggesting an important region of chile domestication and center of diversity. The present sampling of loci did not conclusively resolve the number and location of domestications, but several lines of evidence suggest multiple independent domestications from widely distributed progenitor populations. 相似文献
69.
Iglesias JA Angelov P Ledezma A Sanchis A 《International journal of neural systems》2010,20(5):355-364
Environments equipped with intelligent sensors can be of much help if they can recognize the actions or activities of their users. If this activity recognition is done automatically, it can be very useful for different tasks such as future action prediction, remote health monitoring, or interventions. Although there are several approaches for recognizing activities, most of them do not consider the changes in how a human performs a specific activity. We present an automated approach to recognize daily activities from the sensor readings of an intelligent home environment. However, as the way to perform an activity is usually not fixed but it changes and evolves, we propose an activity recognition method based on Evolving Fuzzy Systems. 相似文献
70.
Araceli Marcela Ramos Marcela Gally María C. García Laura Levin 《Revista iberoamericana de micología》2010,27(4):186-190
BackgroundColletotrichum truncatum is the most common pathogenic fungus associated with soybean anthracnose, a prevalent disease in Argentina. Pectinolytic enzymes are involved in the pathogenicity of a wide range of plant pathogenic fungi.ObjectivesTo explore pectinolytic enzyme production in Argentinian Colletotrichum strains isolated from diseased soybean plants from different geographic locations, as a preliminary step to establish the biological role of the pectinolytic enzymes in the Colletotrichum spp.–soybean system, yet unknown.MethodsTen strains were screened for in vitro pectinolytic enzyme production on a defined medium based on pectin as carbon source.ResultsAll isolates were able to grow in this medium and polymethylgalacturonase (PMG), polygalacturonase (PG) and pectin lyase (PL) activities were detected. On the whole, the peak of polygalacturonases activities preceded the day of maximum growth, while PL activity reached its highest level afterwards. Strain BAFC 3097 (from Santa Fe province) yielded high titles of the three enzymes (1.08 U/ml PG, 1.05 U/ml PMG, 156 U/ml PL), after a short incubation period (7–10 days). Low synthesis of polygalacturonases in cultures containing glucose as unique carbon source suggests that these enzymes are constitutive in contrast with PL, which was not detected.ConclusionsThe disparity observed in enzyme production among strains cannot be related to fungal growth, since no major differences in mycelial yield were found; it was not connected with their geographic origin, but might be associated with differences in virulence among strains not yet evaluated. 相似文献