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281.
The quality of running waters is reflected in the composition of benthic diatom assemblages. The biological assessment of changes in the composition, and thus of changes in water quality, was carried out in the lowland mid-sized Bzura River, Central Poland, over the period of 30 years. The benthic diatom material consisted of samples collected in two investigation periods, in 1972 and in 2003–2004. The methods applied were three diatom indices, IPS — Specific Pollution Sensitivity Index, GDI — Genetic Diatom Index and TDI —Trophic Diatom Index, and the OMNIDIA computer program, which are commonly used in Europe. The aim of the study was demonstrating the process of restoration that occurred in the river. The Bzura was included to the most polluted ones in Poland till 1996. Since 1998 a gradual improvement in water quality has been observed, which is caused by a number of biological-technical measures, mostly a proper organization of sewage management in most cites located on the river. In 1972 the IPS classified Bzura water into Water Quality Class IV-V, while in 2003–2004 it reached much higher values, i.e. Class III–IV. On the basis of the GDI Class III was determined in the whole river in 2003–2004, while its values indicated Class III–IV in 1972. The trophic index, TDI attributed Bzura water to the eutrophic to hypereutrophic zone in 2003–2004, and to one degree better water, i.e. from the mesoeutrophic to eutrophic zone, in 1972.  相似文献   
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BackgroundThe vast majority of systematic reviews are planned retrospectively, once most eligible trials have completed and reported, and are based on aggregate data that can be extracted from publications. Prior knowledge of trial results can introduce bias into both review and meta-analysis methods, and the omission of unpublished data can lead to reporting biases. We present a collaborative framework for prospective, adaptive meta-analysis (FAME) of aggregate data to provide results that are less prone to bias. Also, with FAME, we monitor how evidence from trials is accumulating, to anticipate the earliest opportunity for a potentially definitive meta-analysis.MethodologyWe developed and piloted FAME alongside 4 systematic reviews in prostate cancer, which allowed us to refine the key principles. These are to: (1) start the systematic review process early, while trials are ongoing or yet to report; (2) liaise with trial investigators to develop a detailed picture of all eligible trials; (3) prospectively assess the earliest possible timing for reliable meta-analysis based on the accumulating aggregate data; (4) develop and register (or publish) the systematic review protocol before trials produce results and seek appropriate aggregate data; (5) interpret meta-analysis results taking account of both available and unavailable data; and (6) assess the value of updating the systematic review and meta-analysis. These principles are illustrated via a hypothetical review and their application to 3 published systematic reviews.ConclusionsFAME can reduce the potential for bias, and produce more timely, thorough and reliable systematic reviews of aggregate data.

Jayne Tierney and coauthors discuss FAME, an approach for adaptive meta-analysis of data from randomised trials.  相似文献   
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ObjectiveThe prevalence of euthyroid sick syndrome (ESS) and its association with the prognosis of COVID-19 and mortality in patients with lung involvement in COVID-19 have not yet been elucidated.MethodsClinical and laboratory data of patients with COVID-19 with or without ESS were collected retrospectively and analyzed on admission. All subjects were admitted to the Department of Internal Diseases and Clinical Pharmacology at Bieganski Hospital between December 2020 and April 2021.ResultsIn total, 310 medical records of patients with COVID-19 were analyzed retrospectively. Among 215 enrolled patients, 82 cases of ESS were diagnosed. The patients with ESS had higher pro-inflammatory factor levels, longer hospitalizations, and a higher risk of requiring high-flow nasal oxygen therapy or intubation than the patients without ESS. The Kaplan-Meier curve indicated that the patients with ESS had a lower probability of survival when computed tomography showed ≤50% parenchymal involvement compared with that in patients without ESS. However, no differences in mortality were noted in those with more than 50% parenchymal involvement. The survival curve showed that ESS was associated with a higher risk of mortality during hospitalization.ConclusionESS is closely associated with a poor prognosis, including longer hospitalizations, more frequent intubation, transfer to the intensive care unit, and a higher mortality rate in patients with COVID-19. ESS is a potential prognostic predictor of survival, regardless of lung involvement in COVID-19.  相似文献   
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