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91.
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On the status of the Serranid fish genus Epinephelus: evidence for paraphyly based upon 16S rDNA sequence 总被引:10,自引:0,他引:10
Historically, attempts to elucidate evolutionary relationships among members of the genus Epinephelus (Teleostei: Serranidae), commonly known as groupers, have been hindered by the overwhelming number of species (98, sensu stricto), a pan global distribution, and the lack of morphological specializations traditionally used in ichthyological classification. To date, no comprehensive phylogenetic study, morphological or molecular, to evaluate the monophyly of this genus has been presented. In this study, previous hypotheses regarding the relationships among the American grouper species and the allied genera were evaluated by examination of mitochondrial DNA sequences of the 16S ribosomal DNA region. A 590-bp region of the 16S rDNA gene was amplified using a universal primer pair for 42 serranid species, including members of the genera Epinephelus, Mycteroperca, and Paranthias from the New World and selected Indo-Pacific congeners. Maximum-parsimony criteria and neighbor-joining analysis dispute the monophyly of the American Epinephelus species as previously hypothesized. The data support the monophyly of Cephalopholis only with the inclusion of the morphologically distinct Paranthias and the monophyly of Mycteroperca with the inclusion of the Indo-Pacific Anyperodon leucogrammicus. 相似文献
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Alexander V. Andreev Franz Hafner Siegfried Klaus Hartmut Gossow 《Journal of Ornithology》2001,142(4):404-424
Summary The Siberian Spruce Grouse (Falcipennis falcipennis) is a species endemic to far-eastern Russia and a close relative toF. canadensis andF. franklinii of North-America. Prior to this study, little was known about the display behaviour, social organisation and seasonal movements of this grouse. We investigated these topics in 1990–1997, in 2 areas, 100 km N and 200 km NW of Komsomolsk/Amur. We caught, measured and marked 80 individuals. We determined the age of cocks by the size of combs and the length of neck feathers. Spatial organisation of the local population was studied by equipping 60 birds with transmitters and following them all-year-round.During the reproductive period males and females were territorial. Winter flocks (2–6 birds) break up by late March or early April, and spring flocks break up 1 month later. Cocks were present at the display ground from April 1 to May 25. Females visited the display grounds from April 25 to May 10. Eggs were laid between May 7 and May 20. The main display performances of cocks (upright posture and tail flicks, walks with tail swish, flutter jumps, flutter flights, drumming flights), courtship and agonistic behaviour were analysed from photographs and video recordings. Three-year-old cocks carried out most of the copulations. During the high season of display, we recorded activity (morning and evening displays, moving versus roosting) during continuous observations and counted flutter jumps, flutter flights and drumming flights.Parts of the displays of the Siberian spruce grouse are more diversified than those of the North-American species. The communication system is perfectly adapted to the dense habitat of the mountain taiga. Different acoustic signals for communication at very short, medium and longer distances seem to have evolved under specific predation pressure. The territorial system is very flexible, ranging from individual display grounds to an arena-like structure. The mating system is polygyny.
Balzverhalten und Paarungssystem des Sichelhuhns (Falcipennis falcipennis Hartlaub 1855)
Zusammenfassung Das Sichelhuhn (Falcipennis falcipennis) als endemisches Raufußhuhn des Fernen Ostens Russlands ist eng verwandt mit den nordamerikanischen FichtenhühnernF. canadensis undF. franklinii. Von 1990–1997 wurden Ökologie und Verhalten dieser Art in zwei Gebieten (100 km N und 200 km NW von Komsomolsk am Amur) studiert. 80 Vögel wurden gefangen, vermessen und markiert. Zwei Maße (Größe der Überaugenwülste und Halsfederlänge) gestatten eine Altersbestimmung der Hähne. 60 besenderte Vögel lieferten rund um das Jahr Daten zu Raum- und Habitatnutzung, Reproduktion und Mortalität. Individuelle Markierung und Ortung zu beliebigen Zeiten erleichterten auch die Verhaltensstudien. In der Reproduktionsperiode besaßen sowohl Hähne als auch Hennen Reviere. Winterflüge aus 2–6 Vögeln lösten sich Ende März/Anfang April auf; die Frühjahresgruppen einen Monat später. Die Hähne waren im Mittel zwischen 1. April und 25. Mai an den Balzplätzen anzutreffen, die Hennen erschienen dort zwischen 25. April und 10. Mai. Zwischen 7. und 20. Mai erfolgte die Eiablage. Die wichtigsten Elemente des Territorialverhaltens (Aufrechthaltung mit Schwanzspreizen, Imponierläufe mit Schwanzfederzischen, Flattersprünge, Flatterflüge und Trommelflüge), Revierverteidigung und Werbung werden nach Foto- und Videoaufzeichnungen beschrieben. Dreijährige Hähne vollzogen die meisten Paarungen. Zwischen 1. und 9. Mai, wenn Werbe- und Paarungsverhalten kulminieren, wurden durch Ganztagsbeobachtungen Morgen- und Abendaktivität, Ortsveränderungen und Ruhephasen quantitativ erfasst, ebenso der tägliche Anteil von Flattersprüngen, Flatter-und Trommelflügen. Im Vergleich zu den nordamerikanischen Geschwisterarten sind Teile des Verhaltensrepertoires des Sichelhuhns zur Balzzeit stärker differenziert. Das Kommunikationssystem ist an dichte Habitate der borealen Bergtaiga angepasst: Verschiedene akustische Signale, die auf sehr kurze, mittlere and längere Distanzen wirken, sind offenbar in Anpassung an den spezifischen Feinddruck entstanden. Das Reviersystem erscheint flexibel: Die Spanne reicht von solitär agierenden Hähnen bis zu Arena — ähnlichen Balzplätzen. Das Paarungssystem ist Polygynie.相似文献
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Anja Ulmer Klaus Dietz Isabelle Hodak Bernhard Polzer Sebastian Scheitler Murat Yildiz Zbigniew Czyz Petra Lehnert Tanja Fehm Christian Hafner Stefan Schanz Martin R?cken Claus Garbe Helmut Breuninger Gerhard Fierlbeck Christoph A. Klein 《PLoS medicine》2014,11(2)
Background
Sentinel lymph node spread is a crucial factor in melanoma outcome. We aimed to define the impact of minimal cancer spread and of increasing numbers of disseminated cancer cells on melanoma-specific survival.Methods and Findings
We analyzed 1,834 sentinel nodes from 1,027 patients with ultrasound node-negative melanoma who underwent sentinel node biopsy between February 8, 2000, and June 19, 2008, by histopathology including immunohistochemistry and quantitative immunocytology. For immunocytology we recorded the number of disseminated cancer cells (DCCs) per million lymph node cells (DCC density [DCCD]) after disaggregation and immunostaining for the melanocytic marker gp100. None of the control lymph nodes from non-melanoma patients (n = 52) harbored gp100-positive cells. We analyzed gp100-positive cells from melanoma patients by comparative genomic hybridization and found, in 45 of 46 patients tested, gp100-positive cells displaying genomic alterations. At a median follow-up of 49 mo (range 3–123 mo), 138 patients (13.4%) had died from melanoma. Increased DCCD was associated with increased risk for death due to melanoma (univariable analysis; p<0.001; hazard ratio 1.81, 95% CI 1.61–2.01, for a 10-fold increase in DCCD + 1). Even patients with a positive DCCD ≤3 had an increased risk of dying from melanoma compared to patients with DCCD = 0 (p = 0.04; hazard ratio 1.63, 95% CI 1.02–2.58). Upon multivariable testing DCCD was a stronger predictor of death than histopathology. The final model included thickness, DCCD, and ulceration (all p<0.001) as the most relevant prognostic factors, was internally validated by bootstrapping, and provided superior survival prediction compared to the current American Joint Committee on Cancer staging categories.Conclusions
Cancer cell dissemination to the sentinel node is a quantitative risk factor for melanoma death. A model based on the combined quantitative effects of DCCD, tumor thickness, and ulceration predicted outcome best, particularly at longer follow-up. If these results are validated in an independent study, establishing quantitative immunocytology in histopathological laboratories may be useful clinically. Please see later in the article for the Editors'' Summary 相似文献98.
A large-scale RNA in vitro selection study systematically identified RNA recognition elements for 205 RNA-binding proteins belonging to families conserved in most eukaryotes. 相似文献
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