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排序方式: 共有115条查询结果,搜索用时 78 毫秒
21.
Michael E. Matheny Josh F. Peterson Svetlana K. Eden Adriana M. Hung Theodore Speroff Khaled Abdel-Kader Sharidan K. Parr T. Alp Ikizler Edward D. Siew 《PloS one》2014,9(8)
Background
Patients with hospitalized acute kidney injury (AKI) are at increased risk for accelerated loss of kidney function, morbidity, and mortality. We sought to inform efforts at improving post-AKI outcomes by describing the receipt of renal-specific laboratory test surveillance among a large high-risk cohort.Methods
We acquired clinical data from the Electronic health record (EHR) of 5 Veterans Affairs (VA) hospitals to identify patients hospitalized with AKI from January 1st, 2002 to December 31st, 2009, and followed these patients for 1 year or until death, enrollment in palliative care, or improvement in renal function to estimated GFR (eGFR) ≥60 L/min/1.73 m2. Using demographic data, administrative codes, and laboratory test data, we evaluated the receipt and timing of outpatient testing for serum concentrations of creatinine and any as well as quantitative proteinuria recommended for CKD risk stratification. Additionally, we reported the rate of phosphorus and parathyroid hormone (PTH) monitoring recommended for chronic kidney disease (CKD) patients.Results
A total of 10,955 patients admitted with AKI were discharged with an eGFR<60 mL/min/1.73 m2. During outpatient follow-up at 90 and 365 days, respectively, creatinine was measured on 69% and 85% of patients, quantitative proteinuria was measured on 6% and 12% of patients, PTH or phosphorus was measured on 10% and 15% of patients.Conclusions
Measurement of creatinine was common among all patients following AKI. However, patients with AKI were infrequently monitored with assessments of quantitative proteinuria or mineral metabolism disorder, even for patients with baseline kidney disease. 相似文献22.
Rosie A. Fisher Charles D. Koven William R. L. Anderegg Bradley O. Christoffersen Michael C. Dietze Caroline E. Farrior Jennifer A. Holm George C. Hurtt Ryan G. Knox Peter J. Lawrence Jeremy W. Lichstein Marcos Longo Ashley M. Matheny David Medvigy Helene C. Muller‐Landau Thomas L. Powell Shawn P. Serbin Hisashi Sato Jacquelyn K. Shuman Benjamin Smith Anna T. Trugman Toni Viskari Hans Verbeeck Ensheng Weng Chonggang Xu Xiangtao Xu Tao Zhang Paul R. Moorcroft 《Global Change Biology》2018,24(1):35-54
Numerous current efforts seek to improve the representation of ecosystem ecology and vegetation demographic processes within Earth System Models (ESMs). These developments are widely viewed as an important step in developing greater realism in predictions of future ecosystem states and fluxes. Increased realism, however, leads to increased model complexity, with new features raising a suite of ecological questions that require empirical constraints. Here, we review the developments that permit the representation of plant demographics in ESMs, and identify issues raised by these developments that highlight important gaps in ecological understanding. These issues inevitably translate into uncertainty in model projections but also allow models to be applied to new processes and questions concerning the dynamics of real‐world ecosystems. We argue that stronger and more innovative connections to data, across the range of scales considered, are required to address these gaps in understanding. The development of first‐generation land surface models as a unifying framework for ecophysiological understanding stimulated much research into plant physiological traits and gas exchange. Constraining predictions at ecologically relevant spatial and temporal scales will require a similar investment of effort and intensified inter‐disciplinary communication. 相似文献
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T.K. Arun Kumar Gail J. Celio P. Brandon Matheny David J. McLaughlin David S. Hibbett P. Manimohan 《Mycological Research》2007,111(3):268-274
The phylogeny of Auriculoscypha anacardiicola, an associate of scale insects in India, is investigated using subcellular characters and MP and Bayesian analyses of combined nuLSU-rDNA, nuSSU-rDNA and 5.8S rDNA sequence data. It has simple septa with a pulley-wheel-shaped pore plug, which is diagnostic of phytoparasitic members of the Pucciniomycetes, and hyphal wall break on branching, a phenomenon unique to some simple septate heterobasidiomycetes. The septal ultrastructure of A. anacardiicola is similar to that of the genus Septobasidium. The close relationship to Septobasidium is also confirmed by rDNA sequence analyses. The polyphyletic nature of the order Platygloeales, noted in earlier studies, is evident from the present molecular analysis as well. The placement of Auriculoscypha in the Platygloeales can no longer be justified and both ultrastructural and molecular evidence strongly support the placement of Auriculoscypha in the Septobasidiales. 相似文献
26.
A Sghaier-Ayadi M Feki I Bezrati-Ben Ayed O Abene MK Ben Fredj K Kaabachi A Chaouachi 《Biology of sport / Institute of Sport》2015,32(4):281-287
Recent reports suggest that hypovitaminosis D in athletes is as common as in the general population. This study was devised to examine vitamin D status and determinants of deficiency in athletes living in a sunny country (Tunisia). One hundred and fifty national elite athletes, training outdoors (n = 83) or indoors (n = 67), were enrolled from January to February 2012. Plasma 25-hydroxyvitamin D was measured by radioimmunoassay. Concentrations were between 50 and 75 nmol · l-1 in 21.3% of participants, between 25 and 50 nmol · l-1 in 55.3% of participants and <25 nmol · l-1 in 14.7% of participants. The concentrations were significantly lower in indoor athletes than outdoor athletes (36.2±19.0 nmol · l-1 vs. 49.1±19.2 nmol · l-1; p < 0.001). In multivariate analysis, vitamin D deficiency (25-hydroxyvitamin D <50 nmol · l-1) was associated with indoor sports [multi-adjusted odds ratio (95% confidence interval), 5.03 (1.64-15.4); p = 0.005], female gender [3.72 (1.44-9.65); p = 0.007] and age < 18 years [2.40 (1.01-5.85); p = 0.05]. Athletes living in sun-rich environments are exposed to a high risk of vitamin D inadequacy. Given the importance of vitamin D in health and athletic ability, targeting sufficient levels of plasma 25-hydroxyvitamin D in athletes is well justified. 相似文献
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PG Kennedy PB Matheny KM Ryberg TW Henkel JK Uehling ME Smith 《Molecular ecology》2012,21(17):4151-4154
Ectomycorrhizal (ECM) fungi play major ecological roles in temperate and tropical ecosystems. Although the richness of ECM fungal communities and the factors controlling their structure have been documented at local spatial scales, how they vary at larger spatial scales remains unclear. In this issue of Molecular Ecology, Tedersoo et al. (2012) present the results of a meta‐analysis of ECM fungal community structure that sheds important new light on global‐scale patterns. Using data from 69 study systems and 6021 fungal species, the researchers found that ECM fungal richness does not fit the classic latitudinal diversity gradient in which species richness peaks at lower latitudes. Instead, richness of ECM fungal communities has a unimodal relationship with latitude that peaks in temperate zones. Intriguingly, this conclusion suggests the mechanisms driving ECM fungal community richness may differ from those of many other organisms, including their plant hosts. Future research will be key to determine the robustness of this pattern and to examine the processes that generate and maintain global‐scale gradients of ECM fungal richness. 相似文献
29.
Guma MK Abdeldaim Kristoffer Strålin Jens Korsgaard Jonas Blomberg Christina Welinder-Olsson Björn Herrmann 《BMC microbiology》2010,10(1):310
Background
Streptococcus pneumoniae and Haemophilus influenzae cause pneumonia and as Neisseria meningitidis they are important agents of meningitis. Although several PCR methods have been described for these bacteria the specificity is an underestimated problem. Here we present a quantitative multiplex real-time PCR (qmPCR) for detection of S. pneumoniae (9802 gene fragment), H. influenzae (omp P6 gene) and N. meningitidis (ctrA gene). The method was evaluated on bronchoalveolar lavage (BAL) samples from 156 adults with lower respiratory tract infection (LRTI) and 31 controls, and on 87 cerebrospinal fluid (CSF) samples from meningitis patients. 相似文献30.
Using simulated data, we compared five methods of phylogenetic tree
estimation: parsimony, compatibility, maximum likelihood, Fitch-
Margoliash, and neighbor joining. For each combination of substitution
rates and sequence length, 100 data sets were generated for each of 50
trees, for a total of 5,000 replications per condition. Accuracy was
measured by two measures of the distance between the true tree and the
estimate of the tree, one measure sensitive to accuracy of branch lengths
and the other not. The distance-matrix methods (Fitch- Margoliash and
neighbor joining) performed best when they were constrained from estimating
negative branch lengths; all comparisons with other methods used this
constraint. Parsimony and compatibility had similar results, with
compatibility generally inferior; Fitch- Margoliash and neighbor joining
had similar results, with neighbor joining generally slightly inferior.
Maximum likelihood was the most successful method overall, although for
short sequences Fitch- Margoliash and neighbor joining were sometimes
better. Bias of the estimates was inferred by measuring whether the
independent estimates of a tree for different data sets were closer to the
true tree than to each other. Parsimony and compatibility had particular
difficulty with inaccuracy and bias when substitution rates varied among
different branches. When rates of evolution varied among different sites,
all methods showed signs of inaccuracy and bias.
相似文献