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991.
Francisco Torres-Gonzalez Ariadne Runte-Geidel Claudio Antonioli Luciane C Wagner Dinarte Ballester Jose Miguel Caldas de Almeida Emiliano Galende Benjamín Vicente Miguel Xavier Manuel Gómez-Beneyto Michael B King Sandra M Saldivia 《Mental health in family medicine》2012,9(2):125-134
Background There is a lack of instruments to measure the needs, stigma and informal care of people with schizophrenia that take account of sociocultural variation and patients'' and formal and informal carers'' opinions and experiences.Aims To develop questionnaires to measure stigma, needs and informal (non-professional) care for people with schizophrenia.Method We undertook the study in seven countries and in English, Spanish and Portuguese. We first held focus group discussions with patients, formal carers (professionals) and informal carers (family and friends) in Spain, the UK, Argentina, Brazil, Chile and Venezuela to elicit the main dimensions of needs, stigma and informal care. We then held nominal group discussions about these dimensions with patients, family members and professionals in Spain, Portugal and the UK, to develop the instruments.Results Three hundred and three people participated in 46 focus groups and results were discussed in three nominal groups, each involving eight participants. Three instruments were developed in this iterative process: needs for care (46 items), stigma (38 items) and informal care (20 items).Conclusions These instruments are based on service users'' and carers'' views and experiences and have cross-cultural validity. They will have application in assessment of outcomes for people with schizophrenia and their families. 相似文献
992.
In this communication, we present a unifying framework to understand the emergence and maintenance of diversity in ecological systems. We do this by developing a deterministic population model including density-dependent limitation in resources and available space. Our model shows that competitive exclusion and neutral coexistence represent different regimes of the same adaptive dynamics suggesting that neutrality is the general result of an adaptive process in a finite habitat with limited energetic resources. Our model explains the emergence of biodiversity through mutation and its maintenance through neutrality. We show that this framework provides the theoretical foundations to understand the emergence and maintenance of diversity in microbial ecosystems. 相似文献
993.
Hélder Dores João Abecasis Regina Ribeiras José Pedro Neves Miguel Mendes 《Cardiovascular ultrasound》2012,10(1):1-4
Gerbode defect is a rare type of left ventricle to right atrium shunt. It is usually congenital in origin, but acquired cases are also described, mainly following infective endocarditis, valve replacement, trauma or acute myocardial infarction. We report a case of a 50-year-old man who suffered an extensive and complex infective endocarditis involving a bicuspid aortic valve, the mitral-aortic intervalvular fibrosa and the anterior leaflet of the mitral valve. After dual valve replacement and annular reconstruction, a shunt between the left ventricle and the right atrium - Gerbode defect, and a severe leak of the mitral prosthesis were detected. Reintervention was performed with successful shunt closure with an autologous pericardial patch and paravalvular leak correction. No major complications occurred denying the immediate post-surgery period and the follow-up at the first year was uneventful. 相似文献
994.
Many studies have linked the processing of different object categories to specific event-related potentials (ERPs) such as the face-specific N170. Despite reports showing that object-related ERPs are influenced by visual stimulus features, there is consensus that these components primarily reflect categorical aspects of the stimuli. Here, we re-investigated this idea by systematically measuring the effects of visual feature manipulations on ERP responses elicited by both structure-from-motion (SFM)-defined and luminance-defined object stimuli. SFM objects elicited a novel component at 200-250 ms (N250) over parietal and posterior temporal sites. We found, however, that the N250 amplitude was unaffected by restructuring SFM stimuli into meaningless objects based on identical visual cues. This suggests that this N250 peak was not uniquely linked to categorical aspects of the objects, but is strongly determined by visual stimulus features. We provide strong support for this hypothesis by parametrically manipulating the depth range of both SFM- and luminance-defined object stimuli and showing that the N250 evoked by SFM stimuli as well as the well-known N170 to static faces were sensitive to this manipulation. Importantly, this effect could not be attributed to compromised object categorization in low depth stimuli, confirming a strong impact of visual stimulus features on object-related ERP signals. As ERP components linked with visual categorical object perception are likely determined by multiple stimulus features, this creates an interesting inverse problem when deriving specific perceptual processes from variations in ERP components. 相似文献
995.
Blanco M Campos F Rodríguez-Yáñez M Arias S Fernández-Ferro J Gómez-Sánchez JC Castillo J 《PloS one》2012,7(2):e30700
The control of temperature during the acute phase of stroke may be a new therapeutic target that can be applied in all stroke patients, however therapeutic window or timecourse of the temperature effect is not well established. Our aim is to study the association between changes in body temperature in the first 72 hours and outcome in patients with ischemic (IS) and hemorrhagic (ICH) stroke. We prospectively studied 2931 consecutive patients (2468 with IS and 463 with ICH). Temperature was obtained at admission, and at 24, 48 and 72 hours after admission. Temperature was categorized as low (<36°C), normal (36–37°C) and high (>37°C). As the main variable, we studied functional outcome at 3 months determined by modified Rankin Scale.Temperature in stroke patients is higher than in controls, and increases gradually in the first 72 hours after stroke. A positive correlation between temperature and stroke severity determined by NIHSS was found at 24 and 48 hours, but not at admission or 72 hours. In a logistic regression model, high temperature was associated with poor outcome at 24 hours (OR 2.05, 95% CI 1.59–2.64, p<0.0001) and 48 hours (OR 1.93, 95% CI 1.08–2.34, p = 0.007), but not at admission or 72 hours.Temperature increases in patients with stroke in the first 72 hours, with the harmful effect of high temperature occurring in the first 48 hours. The neuroprotective effect of low temperature occurs within the first 24 hours from stroke onset. 相似文献
996.
997.
Labarrere CA Woods JR Hardin JW Campana GL Ortiz MA Jaeger BR Baldridge LA Pitts DE Kirlin PC 《PloS one》2012,7(4):e36100
Background
Cardiac allograft vasculopathy (CAV) is the principal cause of long-term graft failure following heart transplantation. Early identification of patients at risk of CAV is essential to target invasive follow-up procedures more effectively and to establish appropriate therapies. We evaluated the prognostic value of the first heart biopsy (median: 9 days post-transplant) versus all biopsies obtained within the first three months for the prediction of CAV and graft failure due to CAV.Methods and Findings
In a prospective cohort study, we developed multivariate regression models evaluating markers of atherothrombosis (fibrin, antithrombin and tissue plasminogen activator [tPA]) and endothelial activation (intercellular adhesion molecule-1) in serial biopsies obtained during the first three months post-transplantation from 172 patients (median follow-up = 6.3 years; min = 0.37 years, max = 16.3 years). Presence of fibrin was the dominant predictor in first-biopsy models (Odds Ratio [OR] for one- and 10-year graft failure due to CAV = 38.70, p = 0.002, 95% CI = 4.00–374.77; and 3.99, p = 0.005, 95% CI = 1.53–10.40) and loss of tPA was predominant in three-month models (OR for one- and 10-year graft failure due to CAV = 1.81, p = 0.025, 95% CI = 1.08–3.03; and 1.31, p = 0.001, 95% CI = 1.12–1.55). First-biopsy and three-month models had similar predictive and discriminative accuracy and were comparable in their capacities to correctly classify patient outcomes, with the exception of 10-year graft failure due to CAV in which the three-month model was more predictive. Both models had particularly high negative predictive values (e.g., First-biopsy vs. three-month models: 99% vs. 100% at 1-year and 96% vs. 95% at 10-years).Conclusions
Patients with absence of fibrin in the first biopsy and persistence of normal tPA in subsequent biopsies rarely develop CAV or graft failure during the next 10 years and potentially could be monitored less invasively. Presence of early risk markers in the transplanted heart may be secondary to ischemia/reperfusion injury, a potentially modifiable factor. 相似文献998.
999.
I Zarraonaindia M Iriondo A Albaina MA Pardo C Manzano WS Grant X Irigoien A Estonba 《PloS one》2012,7(7):e42201
Geographic surveys of allozymes, microsatellites, nuclear DNA (nDNA) and mitochondrial DNA (mtDNA) have detected several genetic subdivisions among European anchovy populations. However, these studies have been limited in their power to detect some aspects of population structure by the use of a single or a few molecular markers, or by limited geographic sampling. We use a multi-marker approach, 47 nDNA and 15 mtDNA single nucleotide polymorphisms (SNPs), to analyze 626 European anchovies from the whole range of the species to resolve shallow and deep levels of population structure. Nuclear SNPs define 10 genetic entities within two larger genetically distinctive groups associated with oceanic variables and different life-history traits. MtDNA SNPs define two deep phylogroups that reflect ancient dispersals and colonizations. These markers define two ecological groups. One major group of Iberian-Atlantic populations is associated with upwelling areas on narrow continental shelves and includes populations spawning and overwintering in coastal areas. A second major group includes northern populations in the North East (NE) Atlantic (including the Bay of Biscay) and the Mediterranean and is associated with wide continental shelves with local larval retention currents. This group tends to spawn and overwinter in oceanic areas. These two groups encompass ten populations that differ from previously defined management stocks in the Alboran Sea, Iberian-Atlantic and Bay of Biscay regions. In addition, a new North Sea-English Channel stock is defined. SNPs indicate that some populations in the Bay of Biscay are genetically closer to North Western (NW) Mediterranean populations than to other populations in the NE Atlantic, likely due to colonizations of the Bay of Biscay and NW Mediterranean by migrants from a common ancestral population. Northern NE Atlantic populations were subsequently established by migrants from the Bay of Biscay. Populations along the Iberian-Atlantic coast appear to have been founded by secondary waves of migrants from a southern refuge. 相似文献
1000.
Michiel van Breugel Paulo van Breugel Patrick A. Jansen Miguel Martínez-Ramos Frans Bongers 《Plant Ecology》2012,213(1):25-34
Competition between neighboring plants plays a major role in the population dynamics of tree species in the early phases of
humid tropical forest succession. We evaluated the relative importance of above- versus below-ground competition during the
first years of old-field succession on soil with low fertility in Southern Mexico, using the premise that competition for
light is size-asymmetric, unlike competition for nutrients. Plant growth is thus expected to be disproportionally impeded
by larger neighbors. We studied how growth and survival of 3.5–5.5 m tall saplings of Cecropia peltata and Trichospermum mexicanum, two pioneer species that dominate the secondary forests in the study region, varied with the abundance and size of neighboring
trees in 1–2 year old secondary vegetation. We found that local neighborhood basal area varied 10-fold (3 to 30 cm2 m-2) and explained most of the variation in diameter and height growth of the target saplings. Most growth variables were strongly
affected by the neighbors bigger than the focal trees with no significant additive effect of the smaller neighbors, indicating
asymmetric competition. Smaller neighbors did have a small but significant additive effect on the diameter growth of Cecropia saplings and stem slenderness of Trichospermum saplings. We conclude that competition for light was more important than belowground competition in this initial phase of
moist tropical forest successional, despite the low soil fertility. 相似文献