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51.
A. Terracciano B. Martin D. Ansari T. Tanaka L. Ferrucci S. Maudsley M. P. Mattson P. T. Costa Jr. 《Genes, Brain & Behavior》2010,9(5):512-518
Brain‐derived neurotrophic factor (BDNF) regulates synaptic plasticity and neurogenesis, and BDNF plasma and serum levels have been associated with depression, Alzheimer's disease, and other psychiatric and neurodegenerative disorders. In a relatively large community sample, drawn from the Baltimore Longitudinal Study of Aging (BLSA), we examine whether BDNF plasma concentration is associated with the Val66Met functional polymorphism of the BDNF gene (n = 335) and with depression‐related personality traits assessed with the NEO‐PI‐R (n = 391). Plasma concentration of BDNF was not associated with the Val66Met variant in either men or women. However, in men, but not in women, BDNF plasma level was associated with personality traits linked to depression. Contrary to the notion that low BDNF is associated with negative outcomes, we found lower plasma levels in men who score lower on depression and vulnerability to stress (two facets of Neuroticism) and higher on Conscientiousness and Extraversion. These findings challenge the prevailing hypothesis that lower peripheral levels of BDNF are a marker of depression. 相似文献
52.
Type-specific reference conditions that describe sites with no or only very minor anthropogenic disturbances are a basic requirement
of the European Water Framework Directive. The reference condition approach implies a previous determination of criteria acceptable
for the definition of near-natural stretches. In this paper, a methodology based on selection and validation procedures is
applied to a Portuguese watershed to guide the identification of reference sites. The methodology consisted of three phases:
(1) a preliminary site inspection through the use of maps, available data and an extensive screening field campaign that resulted
in the selection of 52 potentially undisturbed small- and medium-sized rivers stretches, ranging from 43 to 1069 m in altitude,
with catchment areas between 4 and 641 km2 and representing siliceous and calcareous riverbeds; (2) a detailed site selection based on ten pre-defined criteria involving
physical/social/biological attributes that indicated catchment land use changes and alien vegetal riparian species as major
human impacts; (3) a site validation procedure involving detailed investigation of benthic macroinvertebrate communities,
riparian vegetation, in-stream habitat quality and chemical parameters that showed riparian wood-related problems as a major
restriction to validate a stretch as a near-natural site. Only about 12% of all investigated river sites, accounting for 600 m
of all 5200 m studied, could be considered as near-reference stretches or sites retaining essential natural functions. Selection
and validation procedures can identify different sites as reference, which reinforces the need for applying both procedures.
The results presented can help to accomplish the requirements of the EU – Water Framework Directive by selecting reference
sites as the first step to establish biological reference conditions and, simultaneously, to form a basis for nature conservation
strategies.
Electronic supplementary material Electronic supplementary material is available for this article at
and accessible for authorised users. 相似文献
53.
Ruth Pulikottil-Jacob Martin Connock Ngianga-Bakwin Kandala Hema Mistry Amy Grove Karoline Freeman Matthew Costa Paul Sutcliffe Aileen Clarke 《PloS one》2016,11(11)
BackgroundTotal hip replacement for end stage arthritis of the hip is currently the most common elective surgical procedure. In 2007 about 7.5% of UK implants were metal-on-metal joint resurfacing (MoM RS) procedures. Due to poor revision performance and concerns about metal debris, the use of RS had declined by 2012 to about a 1% share of UK hip procedures. This study estimated the lifetime cost-effectiveness of metal-on-metal resurfacing (RS) procedures versus commonly employed total hip replacement (THR) methods.Conclusion/SignificanceOur results imply that in most cases RS has not been a cost-effective resource and should probably not be adopted by decision makers concerned with the cost effectiveness of hip replacement, or by patients concerned about the likelihood of revision, regardless of patient age or gender. 相似文献
54.
Orlov A. M. Sytov A. M. Marí N. Figueroa D. E. Barbini S. A. Costa P. A. S. Marin Y. H. Mincarone M. M. 《Journal of Ichthyology》2019,59(2):174-185
Journal of Ichthyology - Long-term data on spatial and bathymetric distributions, preferred bottom temperatures, length and weight of blue hake Antimora rostrata caught off the Atlantic coast of... 相似文献
55.
Bioinsecticides are important in the control of disease vectors, but data regarding their physiological effects on target insects are incomplete. This study describes morphological changes that occur in the midgut of third instar Aedes aegypti L. (Diptera: Culicidae) following treatment with a methanolic extract of Annona coriacea (Magnoliales: Annonaceae). Dissected midguts were subdivided into anterior and posterior regions and analyzed by light and scanning electron microscopy. Insects exposed to the extract displayed intense, destructive cytoplasmic vacuolization in columnar and regenerative midgut cells. The apical surfaces of columnar cells exhibited cytoplasmic protrusions oriented toward the lumen, suggesting that these cells could be involved in apocrine secretory processes and/or apoptosis. We report that A. coriacea extracts induced morphological alterations in the midgut of A. aegypti midgut larvae, supporting the use of plant extracts for control of the dengue vector. 相似文献
56.
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58.
Kátia Regina da Silva Roberto Costa Elizabeth Sartori Crevelari Marianna Sobral Lacerda Caio Marcos de Moraes Albertini Martino Martinelli Filho José Eduardo Santana Jo?o Ricardo Nickenig Vissoci Ricardo Pietrobon Jacson V. Barros 《PloS one》2013,8(7)
Background
The ability to apply standard and interoperable solutions for implementing and managing medical registries as well as aggregate, reproduce, and access data sets from legacy formats and platforms to advanced standard formats and operating systems are crucial for both clinical healthcare and biomedical research settings.Purpose
Our study describes a reproducible, highly scalable, standard framework for a device registry implementation addressing both local data quality components and global linking problems.Methods and Results
We developed a device registry framework involving the following steps: (1) Data standards definition and representation of the research workflow, (2) Development of electronic case report forms using REDCap (Research Electronic Data Capture), (3) Data collection according to the clinical research workflow and, (4) Data augmentation by enriching the registry database with local electronic health records, governmental database and linked open data collections, (5) Data quality control and (6) Data dissemination through the registry Web site. Our registry adopted all applicable standardized data elements proposed by American College Cardiology / American Heart Association Clinical Data Standards, as well as variables derived from cardiac devices randomized trials and Clinical Data Interchange Standards Consortium. Local interoperability was performed between REDCap and data derived from Electronic Health Record system. The original data set was also augmented by incorporating the reimbursed values paid by the Brazilian government during a hospitalization for pacemaker implantation. By linking our registry to the open data collection repository Linked Clinical Trials (LinkedCT) we found 130 clinical trials which are potentially correlated with our pacemaker registry.Conclusion
This study demonstrates how standard and reproducible solutions can be applied in the implementation of medical registries to constitute a re-usable framework. Such approach has the potential to facilitate data integration between healthcare and research settings, also being a useful framework to be used in other biomedical registries. 相似文献59.
Nucleolar persistence during spermatogenesis of the genus Rhodnius (Hemiptera,Triatominae) 下载免费PDF全文
60.
Cecilio CA Costa EH Ucelli P Chaves CA Toffoli MC Flores CA Cunha FQ Ferreira SH Tamashiro WM 《Mediators of inflammation》1997,6(1):46-52
Macrophages harvested from the peritoneal cavities of rats release a neutrophil chemotactic factor (MNCF) in response to stimulation with Gram-negative bacterial lipopolysaccharide (LPS). MNCF has been shown to be active in rats treated with dexamethasone, a glucocorticoid that usually inhibits the neutrophil migration induced in this species by interleukin (IL)-1, tumour necrosis factor alpha (TNFalpha), IL-8, C5a and leukotriene B(4) (LTB(4)). Here we report that macrophages harvested from peritoneal cavities of mice, and stimulated in vitro with LPS, also release a factor that induces neutrophil migration in dexamethasone-treated animals. This chemotactic activity was neutralized by the incubation of the LPS-stimulated macrophage supernatants with a purified polyclonal IgG anti-mouse TNFalpha. In addition, significant amounts of TNF were detected in the supernatants. The neutrophil migration induced by intraperitoneal administration of recombinant murine TNFalpha was also unaffected by pretreatment of the mice with dexamethasone. Moreover, neutrophil migration induced by intraperitoneal injection of LPS was completely blocked by pretreatment of the mice with a monoclonal antibody against murine TNFalpha. In conclusion, our results support the hypothesis that, in contrast to the role of TNF in rats (where it indirectly induces neutrophil migration), in mice, it may be an important mediator in the recruitment of neutrophils to inflammatory sites. 相似文献