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21.
The European Water Framework Directive (WFD) (2000/60/EC) requires assessing the ecological quality status of water bodies,
and gives great importance to the biological components of the ecosystem. Within this framework, a multimetric, fuzzy-based
index for the evaluation of environmental quality (FINE: fuzzy index of ecosystem integrity) has been developed using data
from several Italian coastal lagoons, gathered with seasonal frequency at diverse sites in each lagoon. The rationale of FINE
is that certain attributes, selected on the basis of established principles of benthic ecology, are fundamental for lagoon
ecosystem function. FINE is composed of seven ecosystem attributes (variables) each of which have ecological relevance for
lagoon ecosystems. Individually, all these attributes are themselves useful indices of environmental conditions. However,
the combination of these attributes into a single fuzzy index, provides a more robust, overall index of the response of the
natural communities to environmental perturbations and avoids misleading or ambiguous results. Each variable is not represented
by a single numerical value, but by several categories that describe its properties: in the present model we considered a
total of seven variables: two with four modalities (low–medium–high–very high), one with three (low–medium–high) and three with two (low–high), plus a qualitative variable (yes–no), that altogether generate 768 rules. FINE is a low-cost, flexible and robust routine index of lagoon ecosystem impairment
and could be of particular benefit to environmental managers and policymakers who require tools capable of expressing the
degree of degradation or environmental quality of different lagoon habitats. For its relative simplicity in the application,
FINE could be a good candidate to assess the environmental quality of Mediterranean transitional ecosystems.
Guest editors: A. Razinkovas, Z. R. Gasiūnaitė, J. M. Zaldivar & P. Viaroli
European Lagoons and their Watersheds: Function and Biodiversity 相似文献
22.
Kelly Yoshizaki J?se Mára Brito Henrique T Moriya Alessandra C Toledo Sandra Ferzilan Ana Paula Ligeiro de Oliveira Isabel D Machado Sandra HP Farsky Luiz FF Silva Milton A Martins Paulo HN Saldiva Thais Mauad Mariangela Macchione 《Respiratory research》2015,16(1)
Background
Diesel exhaust particles (DEPs) are deposited into the respiratory tract and are thought to be a risk factor for the development of diseases of the respiratory system. In healthy individuals, the timing and mechanisms of respiratory tract injuries caused by chronic exposure to air pollution remain to be clarified.Methods
We evaluated the effects of chronic exposure to DEP at doses below those found in a typical bus corridor in Sao Paulo (150 μg/m3). Male BALB/c mice were divided into mice receiving a nasal instillation: saline (saline; n = 30) and 30 μg/10 μL of DEP (DEP; n = 30). Nasal instillations were performed five days a week, over a period of 90 days. Bronchoalveolar lavage (BAL) was performed, and the concentrations of interleukin (IL)-4, IL-10, IL-13 and interferon-gamma (INF-γ) were determined by ELISA-immunoassay. Assessment of respiratory mechanics was performed. The gene expression of Muc5ac in lung was evaluated by RT-PCR. The presence of IL-13, MAC2+ macrophages, CD3+, CD4+, CD8+ T cells and CD20+ B cells in tissues was analysed by immunohistochemistry. Bronchial thickness and the collagen/elastic fibers density were evaluated by morphometry. We measured the mean linear intercept (Lm), a measure of alveolar distension, and the mean airspace diameter (D0) and statistical distribution (D2).Results
DEP decreased IFN-γ levels in BAL (p = 0.03), but did not significantly alter IL-4, IL-10 and IL-13 levels. MAC2+ macrophage, CD4+ T cell and CD20+ B cell numbers were not altered; however, numbers of CD3+ T cells (p ≤ 0.001) and CD8+ T cells (p ≤ 0.001) increased in the parenchyma. Although IL-13 (p = 0.008) expression decreased in the bronchiolar epithelium, Muc5ac gene expression was not altered in the lung of DEP-exposed animals. Although respiratory mechanics, elastic and collagen density were not modified, the mean linear intercept (Lm) was increased in the DEP-exposed animals (p ≤ 0.001), and the index D2 was statistically different (p = 0.038) from the control animals.Conclusion
Our data suggest that nasal instillation of low doses of DEP over a period of 90 days results in alveolar enlargement in the pulmonary parenchyma of healthy mice.Electronic supplementary material
The online version of this article (doi:10.1186/s12931-015-0172-z) contains supplementary material, which is available to authorized users. 相似文献23.
A set of multiplex panels of microsatellite markers for rapid molecular characterization of rice accessions 总被引:1,自引:0,他引:1
Marco Pessoa-Filho André Beló António AN Alcochete Paulo HN Rangel Márcio E Ferreira 《BMC plant biology》2007,7(1):23
Background
This study aimed to analyze the efficiency of three new microsatellite multiplex panels, which were designed to evaluate a total of 16 loci of the rice genome, based on single PCR reactions of each panel. A sample of 548 accessions of traditional upland rice landraces collected in Brazil in the last 25 years was genotyped, a database of allelic frequencies was established, estimates of genetic parameters were performed and analysis of genetic structure of the collection was developed. 相似文献24.
Maged1, a new regulator of skeletal myogenic differentiation and muscle regeneration 总被引:1,自引:0,他引:1
Tuan HN Nguyen Mathieu JM Bertrand Christiane Sterpin Younes Achouri Olivier RY De Backer 《BMC cell biology》2010,11(1):57
Background
In normal adult skeletal muscle, cell turnover is very slow. However, after an acute lesion or in chronic pathological conditions, such as primary myopathies, muscle stem cells, called satellite cells, are induced to proliferate, then withdraw definitively from the cell cycle and fuse to reconstitute functional myofibers. 相似文献25.
CA Siegrist C van Delden M Bel C Combescure C Delhumeau M Cavassini O Clerc S Meier K Hadaya PM Soccal S Yerly L Kaiser B Hirschel A Calmy;HN Study Group;Swiss HIV Cohort Study 《PloS one》2012,7(7):e40428
Background
Memory responses require immune competence. We assessed the influence of priming with AS03-adjuvanted pandemic vaccine (Pandemrix®) on memory responses of HIV patients, kidney recipients (SOT) and healthy controls (HC).Method
Participants (HIV: 197, SOT: 53; HC: 156) were enrolled in a prospective study and 390/406 (96%) completed it. All had been primed in 2009/2010 with 1 (HC) or 2 (patients) doses of Pandemrix®, and were boosted with the 2010/2011 seasonal influenza vaccine. Geometric mean titres and seroprotection rates were measured 12 months after priming and 4 weeks after boosting. Primary and memory responses were directly compared in 191 participants (HCW: 69, HIV: 71, SOT: 51) followed during 2 consecutive seasons.Results
Most participants (HC: 77.8%, HIV: 77.6%, SOT: 66%) remained seroprotected at 12 months post-priming. Persisting A/09/H1N1 titers were high in HIV (100.2) and HC (120.1), but lower in SOT (61.4) patients. Memory responses reached higher titers in HIV (507.8) than in HC (253.5) and SOT (136.9) patients. Increasing age and lack of HAART reduced persisting and memory responses, mainly influenced by residual antibody titers. Comparing 2009/2010 and 2010/2011 titers in 191 participants followed for 2 seasons indicated lower post-2010/2011 titers in HC (240.2 vs 313.9), but higher titers in HIV (435.7 vs 338.0) and SOT (136 vs 90.3) patients.Conclusions
Priming with 2 doses of Pandemrix® elicited persistent antibody responses and even stronger memory responses to non-adjuvanted seasonal vaccine in HIV patients than 1 dose in healthy subjects. Adjuvanted influenza vaccines may improve memory responses of immunocompromised patients.Trial Registration
ClinicalTrials.gov NCT01022905相似文献26.
Selective influence of Sox2 on POU transcription factor binding in embryonic and neural stem cells 下载免费PDF全文
27.
As a tool to better understand the organization of the olfactory pathway three monoclonal antibodies have been isolated and characterized each having a unique staining pattern in the antenna and antennal lobe of Drosophila melanogaster. Monoclonal antibody F14-2D6 stains sensilla coeloconica and thick sensilla basiconica in the funiculus, Y1-3D10 stains only a few sensilla especially in and around the sacculus, while F15-12E8 stains all the sensilla. All three antibodies stain a subset of the glomeruli in the antennal lobe, of which 11 glomeruli are stained in common by all three antibodies. These antibodies could be used to study projection patterns of the sensilla into the antennal lobe. Glomerular staining was observed at different developmental times with the different antibodies. F15-12E8 stains all the glomeruli at eclosion, Y1-3D10 stains only a few glomeruli at eclosion but most glomeruli are stained by the first day after eclosion. F14-2D6 stains all glomeruli only after eclosion. F15-12E8 also stains the mushroom bodies. The antigen recognized by F14-2D6 in the glomeruli shows an increase with age of the flies, measured as increased intensity of staining. These observations suggest that age-related changes continue in the antennal lobe of the flies even after eclosion. These antibodies could therefore serve as unique markers for other studies on the development of the olfactory system. 相似文献
28.
Background
Breeding programs are usually reluctant to evaluate and use germplasm accessions other than the elite materials belonging to their advanced populations. The concept of core collections has been proposed to facilitate the access of potential users to samples of small sizes, representative of the genetic variability contained within the gene pool of a specific crop. The eventual large size of a core collection perpetuates the problem it was originally proposed to solve. The present study suggests that, in addition to the classic core collection concept, thematic core collections should be also developed for a specific crop, composed of a limited number of accessions, with a manageable size. 相似文献29.
Contrasting levels of DNA polymorphism at the autosomal and X-linked visual color pigment loci in humans and squirrel monkeys 总被引:1,自引:0,他引:1
The X-linked color pigment (opsin) locus is known to be highly polymorphic
in the squirrel monkey and other New World monkeys. To see whether this is
also the case for the autosomal (blue) opsin locus, we obtained 32 squirrel
monkey and 30 human blue opsin gene sequences. No amino acid polymorphism
was found in either the squirrel monkey sample or the human sample,
contrary to the situation at the X-linked opsin locus. This sharp contrast
in the level of polymorphism might be due to differences in gene expression
between the autosomal and the X-linked loci. At the X-linked locus,
heterozygote advantage can occur because, owing to X-inactivation, the two
alleles in a heterozygote are expressed in different cone cells, producing
two types of cone cell, whereas at the autosomal locus, heterozygote
advantage cannot occur because the two alleles in a heterozygote are
expressed in the same cone cells, producing only one type of cone cell
(i.e., phenotypically a homozygote). From the sequence data, the levels of
nucleotide diversity (pi, i.e., the number of nucleotide differences per
site) are estimated: for the human sample, pi = 0.00% per nondegenerate
site, 0.00% per twofold degenerate site, and 0.04% per fourfold degenerate
site in the coding regions and 0.01% per site in intron 4; for the squirrel
monkey sample, pi = 0.00% per nondegenerate site, 0.00% per twofold
degenerate site, and 0.15% per fourfold degenerate site in the coding
regions and 0.17% per site in intron 4. The blue opsin genes from the
common and pygmy chimpanzees, the gorilla, the capuchin, and the howler
monkey were also sequenced. Features critical to the function of the opsin
are well conserved in all known mammalian sequences. However, the
interhelical loops are, on average, actually more conservative than the
transmembrane helical regions. In addition, these sequence data and those
from some other genes indicate that the common and pygmy chimpanzees are
not closely related, their divergence data being from one third to one half
the date of the human-chimpanzee divergence.
相似文献
30.
A functional immunoassay, that has proved very useful, is described for screening and identifying monoclonal antibodies (McAbs)
against scarce and labile enzymes. This method does not require purified enzyme or antigen and it has been successfully applied
to isolate three hybridomas secreting McAbs to NADPH:nitrate reductase from the chloronema cells of the mossFunaria hygrometrica. Briefly, the protocol involves: adsorption of murine antibodies from hybridoma supernatants by rabbit antimouse IgG antibody
pre-adsorbed toStaphylococcus aureus cells (SAC), reaction with crude extract for 15 min, sedimentation of the SAC complex by centrifugation and measurement of
residual enzymatic activity in the supernatant. A depletion indicates the presence of antibodies that bind to the active enzyme.
The method is rapid, sensitive and versatile enough to be used to isolate McAbs with exquisite specificities. The three isolated
McAbs recognized nitrate reductase protein in a conformation-independent and/or a conformation-dependent manner. 相似文献