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241.
Surgery is an increasingly common and expensive mode of medical intervention. The ethical dimensions of the surgeon‐patient relationship, including respect for personal autonomy and informed consent, are much discussed; but broader equity issues have not received the same attention. This paper extends the understanding of surgical ethics by considering the nature of evidence in surgery and its relationship to a just provision of healthcare for individuals and their populations. 相似文献
242.
Using conditional power of network meta‐analysis (NMA) to inform the design of future clinical trials
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Adriani Nikolakopoulou Dimitris Mavridis Georgia Salanti 《Biometrical journal. Biometrische Zeitschrift》2014,56(6):973-990
Clinical trials are typically designed with an aim to reach sufficient power to test a hypothesis about relative effectiveness of two or more interventions. Their role in informing evidence‐based decision‐making demands, however, that they are considered in the context of the existing evidence. Consequently, their planning can be informed by characteristics of relevant systematic reviews and meta‐analyses. In the presence of multiple competing interventions the evidence base has the form of a network of trials, which provides information not only about the required sample size but also about the interventions that should be compared in a future trial. In this paper we present a methodology to evaluate the impact of new studies, their information size, the comparisons involved, and the anticipated heterogeneity on the conditional power (CP) of the updated network meta‐analysis. The methods presented are an extension of the idea of CP initially suggested for a pairwise meta‐analysis and we show how to estimate the required sample size using various combinations of direct and indirect evidence in future trials. We apply the methods to two previously published networks and we show that CP for a treatment comparison is dependent on the magnitude of heterogeneity and the ratio of direct to indirect information in existing and future trials for that comparison. Our methodology can help investigators calculate the required sample size under different assumptions about heterogeneity and make decisions about the number and design of future studies (set of treatments compared). 相似文献
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Species of the tribe Adramini (Tephritidae: Trypetinae) are usually slender, and some specific species have eyes borne at the ends of their long stalks. This tribe is mainly distributed in the tropics and subtropics of the Afrotropical, Oriental and Australasian Regions; relatively few species occur in the Palearctic and Nearctic Regions. The phylogeny of the tribe Adramini is presented here based on analysis of morphological and molecular information (DNA sequences of nuclear 28S rDNA, mitochondrial COI and COII, and 16S rDNA genes) for its representative species in most genera. Three monophyletic groups (Adrama‐com‐group, Pelmatops‐com‐group and Dimeringophrys‐com‐group) were discovered in the combined morphological and molecular tree. The results showed moderate support for the monophyly of Adramini and strong support for most of its genera. However, Euphranta appears to be polyphyletic. Sapadrama, Celidodacus and Euphranta are basal taxon, and Coelopacidia, Soita and Trypanophion are closely related to the stalk‐eyed fruit flies (Pelmatops + Pseudopelmatops). A hypothesis regarding the morphology–function relationships for two main groups of Adramini (Adrama‐group and Pelmatops‐group) with different evolving probabilities is inferred. Sapadrama is proposed be removed from Adramini; a new genus, Ichneumonomacula Chen gen. n. and a new species Ichneumonmacula wangyongi Chen sp. n., are recognized and described, and a key to recognize the genera of Adramini around the world is provided. 相似文献
245.
《Indian pacing and electrophysiology journal》2021,21(6):367-393
In view of the increasing complexity of both cardiovascular implantable electronic devices (CIEDs) and patients in the current era, practice guidelines, by necessity, have become increasingly specific. This document is an expert consensus statement that has been developed to update and further delineate indications and management of CIEDs in pediatric patients, defined as ≤21 years of age, and is intended to focus primarily on the indications for CIEDs in the setting of specific disease categories. The document also highlights variations between previously published adult and pediatric CIED recommendations and provides rationale for underlying important differences. The document addresses some of the deterrents to CIED access in low- and middle-income countries and strategies to circumvent them. The document sections were divided up and drafted by the writing committee members according to their expertise. The recommendations represent the consensus opinion of the entire writing committee, graded by class of recommendation and level of evidence. Several questions addressed in this document either do not lend themselves to clinical trials or are rare disease entities, and in these instances recommendations are based on consensus expert opinion. Furthermore, specific recommendations, even when supported by substantial data, do not replace the need for clinical judgment and patient-specific decision-making. The recommendations were opened for public comment to Pediatric and Congenital Electrophysiology Society (PACES) members and underwent external review by the scientific and clinical document committee of the Heart Rhythm Society (HRS), the science advisory and coordinating committee of the American Heart Association (AHA), the American College of Cardiology (ACC), and the Association for European Paediatric and Congenital Cardiology (AEPC). The document received endorsement by all the collaborators and the Asia Pacific Heart Rhythm Society (APHRS), the Indian Heart Rhythm Society (IHRS), and the Latin American Heart Rhythm Society (LAHRS). This document is expected to provide support for clinicians and patients to allow for appropriate CIED use, appropriate CIED management, and appropriate CIED follow-up in pediatric patients. 相似文献
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If, as recently suggested, Lake Victoria dried up completely in theLate Pleistocene and refilled c 12,400 BP, not only must therate of speciation of its flock of cichlid fishes have been extremelyrapid but, more significantly, so too must the rate of morphologicaldifferentiation. Such desiccation also implies that fishes belongingto seven other families achieved endemic status since the lakerefilled, and in one case became generically distinct, acquiredstriking morphological/physiological adaptations to life in deepwater, and split into two species. Such rapid evolution within thesefamilies appears to have no parallel in Africa. This suggests thatprudence be applied in the interpretation of what appears to beunambiguous evidence, especially as this seems to be at variance withwhat also appears to be convincing geophysical evidence of adifferent kind. 相似文献