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41.
Ligia Noronha 《EcoHealth》2004,1(2):SU16
This article briefly discusses the evolution of ecosystem approaches, and illustrates the use of ecosystem approaches to assess human health and well-being in a mining context. It discusses the various elements that help distinguish such approaches from other approaches. Well-being here is understood broadly in terms of its “constituents” and “determinants,” of which health is an important constituent. Ecological, health, and social assessments highlighted a number of impacts from mining activity in Goa, India. These generated a list of issues of concern that were validated by stakeholders—community, industry, and government—which served as a basis for the development of tools to track mining-induced changes in health and well-being. The article concludes by reflecting on some of the challenges posed by the use of ecosystem approaches to assessing human health and well-being. 相似文献
42.
The abundance of calcareous green algae was recorded quarterly at 28 sites within the Florida Keys National Marine Sanctuary (FKNMS) for a period of 7 years as part of a sea grass monitoring program. To evaluate the validity of using the functional‐form group approach, we designed a sampling method that included the functional‐form group and the component genera. This strategy enabled us to analyze the spatiotemporal patterns in the abundance of calcareous green algae as a group and to describe synchronous behavior among its genera through the application of a nonlinear regression model to both categories of data. Spatial analyses revealed that, in general, all genera displayed long‐term trends of increasing abundance at most sites; however, at some sites the long‐term trends for genera opposed one another. Strong synchrony in the timing of seasonal changes was found among all genera, possibly reflecting similar reproductive and seasonal growth pattern, but the variability in the magnitude of seasonal changes was very high among genera and sites. No spatial patterns were found in long‐term or seasonal changes; the only significant relation detected was for slope, with sites closer to land showing higher values, suggesting that some factors associated with land proximity are affecting this increase. We conclude that the abundances of genera behaved differently from the functional‐form group, indicating that the use of the functional‐form group approach may be unsuitable to detect changes in sea grass community structure in the FKNMS at the existing temporal and spatial scale of the monitoring program. 相似文献
43.
A. Arnaiz-Villena S. Rodriguez de Córdoba F. Vela J. C. Pascual J. Cerveró A. Bootello 《Human genetics》1981,58(3):344-348
Summary Frequencies of recently described HLA-A,-B (antigens or splits) and HLA-C and HLA-DR antigens are studied in a 450 normal Spaniards sample. The linkage disequilibria are also calculated. HLA-DR7 is more frequent than in any other population studied. Aw30-B18 and Aw33-B14 associations are common and specific Spanish, Basque, and Sardinian HLA features. A11-B27 association is found in our Spanish sample and also in Basques.HLA-Bw4,-Bw6 antigens are analyzed by family mating and segregation and also using unrelated individuals. It shows a good fit as a genetic system. HLA-B antigens are included either in Bw4 or Bw6 according to expectations from other Caucasoid population results. The possibility of a common and North African origen (Iberians) for Spaniards, Basques, and Sardinians is discussed on the basis of presently available HLA data. 相似文献
44.
Ligia Subitoni Antonio Roberta Ribeiro Costa Marcelo Damário Gomes Wamberto Antonio Varanda 《Purinergic signalling》2009,5(3):277-287
ATP acts on cellular membranes by interacting with P2X (ionotropic) and P2Y (metabotropic) receptors. Seven homomeric P2X
receptors (P2X1–P2X7) and seven heteromeric receptors (P2X1/2, P2X1/4, P2X1/5, P2X2/3, P2X2/6, P2X4/6, P2X4/7) have been described. ATP treatment of Leydig cells leads to an increase in [Ca2+]i and testosterone secretion, supporting the hypothesis that Ca2+ signaling through purinergic receptors contributes to the process of testosterone secretion in these cells. Mouse Leydig
cells have P2X receptors with a pharmacological and biophysical profile resembling P2X2. In this work, we describe the presence of several P2X receptor subunits in mouse Leydig cells. Western blot experiments
showed the presence of P2X2, P2X4, P2X6, and P2X7 subunits. These results were confirmed by immunofluorescence. Functional results support the hypothesis that heteromeric
receptors are present in these cells since 0.5 μM ivermectin induced an increase (131.2 ± 5.9%) and 3 μM ivermectin a decrease
(64.2 ± 4.8%) in the whole-cell currents evoked by ATP. These results indicate the presence of functional P2X4 subunits. P2X7 receptors were also present, but they were non-functional under the present conditions because dye uptake experiments with
Lucifer yellow and ethidium bromide were negative. We conclude that a heteromeric channel, possibly P2X2/4/6, is present in Leydig cells, but with an electrophysiological and pharmacological phenotype characteristic of the P2X2 subunit. 相似文献
45.
Moreno-Valenzuela OA Minero-García Y Brito-Argáez L Carbajal-Mora E Echeverría O Vázquez-Nin G Loyola-Vargas VM 《Molecular biotechnology》2003,23(1):11-18
We investigated the intracellular distribution of tryptophan decarboxylase (TDC) (EC 4.1.1.28) in Catharanthus roseus hairy roots using immunofluorescence and immunogold techniques. TDC was detected by immunofluorescence localization in the
cytosol and in the apoplastic region of the meristematic cells of the roots, with a slight enrichment in the epidermal cells
of the root cap and in the meristematic region. In the enlargement zone, TDC was localized only in the first three layers
of the cortex. In the maturation zone, the enzyme was not present. Immunogold studies confirmed that the enzyme was localized
in the cytosol of the meristematic region, and intense gold labeling was found in the apoplastic zone. A protein fraction
isolated from the apoplastic zone and assayed for TDC activity showed high activity. 相似文献
46.
Zamora L Fernández-Garayzábal JF Palacios MA Sánchez-Porro C Svensson-Stadler LA Domínguez L Moore ER Ventosa A Vela AI 《Systematic and applied microbiology》2012,35(1):24-29
Genotypic and phenotypic analyses were performed on five Gram-negative, catalase and oxidase-positive, rod-shaped bacteria isolated from the gill and liver of four rainbow trout. Studies based on comparative 16S rRNA gene sequence analysis showed that the five new isolates shared 99.8-100% sequence similarity and that they belong to the genus Chryseobacterium. The nearest phylogenetic neighbours of the strain 701B-08(T) were Chryseobacterium ureilyticum F-Fue-04IIIaaaa(T) (99.1% 16S rRNA gene sequence similarity) and Chryseobacterium joosteii LMG 18212(T) (98.6%). DNA-DNA hybridization values between the five isolates were 91-99% and ranged from 2 to 53% between strain 701B-08(T) and the type strains of phylogenetically closely related species of Chryseobacterium. Strain 701B-08(T) had a DNA G+C content of 36.3 mol%, the major fatty acids were iso-C(15:0), iso-C(17:1)ω9c, C(16:1)ω6c and iso-C(17:0) 3-OH and the predominant respiratory quinone was MK-6. The novel isolates were distinguished from related Chryseobacterium species by physiological and biochemical tests. The genotypic and phenotypic properties of the isolates from rainbow trout suggest their classification as representatives of a novel species of the genus Chryseobacterium, for which the name Chryseobacterium oncorhynchi sp. nov. is proposed. The type strain is 701B-08(T) (=CECT 7794(T)=CCUG 60105(T)). 相似文献
47.
48.
Batch cultures of Azotobacter vinelandii grown in phosphate-deficient media were compared with control cultures grown in phosphate-sufficient media. Phosphate limitation was assessed by total cell yield and by growth kinetics. Although cell protein, nucleic acids, and early growth rate were unaffected by phosphate deficiency, cell wall structure, oxygen uptake, and cell viability were significantly affected. Also, phosphate-limited cells contained much larger amounts of poly-beta-hydroxybutyric acid but lower adenylate nucleotide energy charge than did control cells. The ratio of adenosine 5'-triphosphate to adenosine 5'-diphosphate was much lower in phosphate-deficient cells. The data indicate a substrate saving choice of three metabolic pathways available to this organism under different growth conditions. 相似文献
49.
The spider tree of life: phylogeny of Araneae based on target‐gene analyses from an extensive taxon sampling 下载免费PDF全文
Ward C. Wheeler Jonathan A. Coddington Louise M. Crowley Dimitar Dimitrov Pablo A. Goloboff Charles E. Griswold Gustavo Hormiga Lorenzo Prendini Martín J. Ramírez Petra Sierwald Lina Almeida‐Silva Fernando Alvarez‐Padilla Miquel A. Arnedo Ligia R. Benavides Silva Suresh P. Benjamin Jason E. Bond Cristian J. Grismado Emile Hasan Marshal Hedin Matías A. Izquierdo Facundo M. Labarque Joel Ledford Lara Lopardo Wayne P. Maddison Jeremy A. Miller Luis N. Piacentini Norman I. Platnick Daniele Polotow Diana Silva‐Dávila Nikolaj Scharff Tamás Szűts Darrell Ubick Cor J. Vink Hannah M. Wood Junxia Zhang 《Cladistics : the international journal of the Willi Hennig Society》2017,33(6):574-616
50.
D. N. Castelblanco‐Martínez J. Padilla‐Saldívar H. A. Hernández‐Arana D. H. Slone J. P. Reid B. Morales‐Vela 《Marine Mammal Science》2013,29(2):E166-E182
Information from 15 satellite‐tracked Antillean manatees (Trichechus manatus manatus) was analyzed in order to assess individual movements, home ranges, and high‐use areas for conservation decisions. Manatees were captured in Chetumal Bay, Mexico, and tagged with Argos‐monitored satellite transmitters. Location of the manatees and physical characteristics were assessed to describe habitat properties. Most manatees traveled to freshwater sources. The Maximum Area Size (MAS) for each manatee was determined using the observation‐area method. Additional kernel densities of 95% home range and 50% Center of Activity (COA) were also calculated, with manatees having 1–3 COAs. Manatees exhibited two different movement patterns: remaining in Chetumal Bay, and long‐distance (up to 240 km in 89 d). The residence time in Chetumal Bay was higher for females (89.6% of time) than for males (72.0%), but the daily travel rate (0.4–0.5 km/d) was similar for both sexes. Most of the COAs fell within Natural Protected Areas (NPA). However, manatees also travel for long distances into unprotected areas, where they face uncontrolled boat traffic, fishing activities, and habitat loss. Conservation of movement corridors may promote long‐distance movements and facilitate genetic exchange. 相似文献