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31.
S.M. Walker P.A. Prodöhl E.M. Hoey I. Fairweather R.E.B. Hanna G. Brennan A. Trudgett 《International journal for parasitology》2012,42(13-14):1193-1199
The liver flukes, Fasciola hepatica and Fasciola gigantica, are considered to be sister species and between them present a major threat worldwide to livestock production. In this study sequence data have been employed from informative regions of the nuclear and mitochondrial genomes of over 200 morphologically F. hepatica-like or F. gigantica-like flukes from Europe, sub-Saharan Africa and South Asia to assess genetic diversity. Evidence is presented for the existence of four well-separated clades: African gigantica-like flukes, Indian gigantica-like flukes, European hepatica-like flukes and African high-altitude hepatica-like flukes. Application of the Biological Species Concept to trematodes is problematic; however, the degree of separation between these groups was sufficient for them to be considered as distinct species using the four times rule for speciation. 相似文献
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Bellwood DR Baird AH Depczynski M González-Cabello A Hoey AS Lefèvre CD Tanner JK 《Oecologia》2012,170(2):567-573
The dynamic nature of coral reefs offers a rare opportunity to examine the response of ecosystems to disruption due to climate change. In 1998, the Great Barrier Reef experienced widespread coral bleaching and mortality. As a result, cryptobenthic fish assemblages underwent a dramatic phase-shift. Thirteen years, and up to 96 fish generations later, the cryptobenthic fish assemblage has not returned to its pre-bleach configuration. This is despite coral abundances returning to, or exceeding, pre-bleach values. The post-bleach fish assemblage exhibits no evidence of recovery. If these short-lived fish species are a model for their longer-lived counterparts, they suggest that (1) the full effects of the 1998 bleaching event on long-lived fish populations have yet to be seen, (2) it may take decades, or more, before recovery or regeneration of these long-lived species will begin, and (3) fish assemblages may not recover to their previous composition despite the return of corals. 相似文献
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Homeobox proteins as sequence-specific transcription factors 总被引:48,自引:0,他引:48
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M. L. Berumen A. S. Hoey W. H. Bass J. Bouwmeester D. Catania J. E. M. Cochran M. T. Khalil S. Miyake M. R. Mughal J. L. Y. Spaet P. Saenz-Agudelo 《Coral reefs (Online)》2013,32(3):737-748
The Red Sea has long been recognized as a region of high biodiversity and endemism. Despite this diversity and early history of scientific work, our understanding of the ecology of coral reefs in the Red Sea has lagged behind that of other large coral reef systems. We carried out a quantitative assessment of ISI-listed research published from the Red Sea in eight specific topics (apex predators, connectivity, coral bleaching, coral reproductive biology, herbivory, marine protected areas, non-coral invertebrates and reef-associated bacteria) and compared the amount of research conducted in the Red Sea to that from Australia’s Great Barrier Reef (GBR) and the Caribbean. On average, for these eight topics, the Red Sea had 1/6th the amount of research compared to the GBR and about 1/8th the amount of the Caribbean. Further, more than 50 % of the published research from the Red Sea originated from the Gulf of Aqaba, a small area (<2 % of the area of the Red Sea) in the far northern Red Sea. We summarize the general state of knowledge in these eight topics and highlight the areas of future research priorities for the Red Sea region. Notably, data that could inform science-based management approaches are badly lacking in most Red Sea countries. The Red Sea, as a geologically “young” sea located in one of the warmest regions of the world, has the potential to provide insight into pressing topics such as speciation processes as well as the capacity of reef systems and organisms to adapt to global climate change. As one of the world’s most biodiverse coral reef regions, the Red Sea may yet have a significant role to play in our understanding of coral reef ecology at a global scale. 相似文献
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OBJECTIVE: To describe the process used to notify pediatric patients who received transfusions of blood or blood products at our institution before donor blood was routinely screened for antibodies to HIV (1985) and hepatitis C virus (1990), and to evaluate the effectiveness of the notification program. DESIGN: Patients who had received transfusions were identified through the hospital''s medical records and the records from the Transfusion Medicine Laboratory. Patients were contacted by registered mail to provide notification of transfusion. A questionnaire was included with the notification to obtain information about the patient''s awareness of the transfusion and whether he or she had undergone or planned to undergo testing for HIV and hepatitis C virus. SETTING: Tertiary care university-affiliated teaching hospital in Hamilton, Ont. PATIENTS: Patients 16 years of age or younger who had received blood products between February 1978 and November 1985. Patients who had received only albumin or immune serum globulin were not included as these products were not associated with viral transmission in Canada. RESULTS: Notification letters were sent to 1546 patients. Of these letters 522 (33.8%) were returned undelivered. Of the 1024 patients contacted 493 (48.1%) responded to the questionnaire, of whom 157 (31.8%) were not aware of their transfusion. A total of 130 (26.4%) of the respondents had already undergone testing for HIV, and 342 (69.4%) indicated that they would undergo such testing as a result of the notification. In contrast, only 30 (6.3%) of 474 respondents had undergone testing for hepatitis C virus, but 425 (89.7%) indicated that they would undergo such testing. Overall, the patients'' response to the notification was neutral or positive; however, a number of patients expressed dissatisfaction and anxiety. CONCLUSIONS: The high proportion of patients who were unaware that they had undergone transfusion and who decided to undergo testing for HIV and hepatitis C virus as a result of notification supports the use of notification programs such as this one. 相似文献