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Fish stocks experiencing high fishing mortality show a tendency to mature earlier and at a smaller size, which may have a genetic component and therefore long-lasting economic and biological effects. To date, the economic effects of such ecoevolutionary dynamics have not been empirically investigated. Using 70 y of data, we develop a bioeconomic model for Northeast Arctic cod to compare the economic yield in a model in which life-history traits can vary only through phenotypic plasticity with a model in which, in addition, genetic changes can occur. We find that evolutionary changes toward faster growth and earlier maturation occur consistently even if a stock is optimally managed. However, if a stock is managed optimally, the evolutionary changes actually increase economic yield because faster growth and earlier maturation raise the stock’s productivity. The optimal fishing mortality is almost identical for the evolutionary and nonevolutionary model and substantially lower than what it has been historically. Therefore, the costs of ignoring evolution under optimal management regimes are negligible. However, if fishing mortality is as high as it has been historically, evolutionary changes may result in economic losses, but only if the fishery is selecting for medium-sized individuals. Because evolution facilitates growth, the fish are younger and still immature when they are susceptible to getting caught, which outweighs the increase in productivity due to fish spawning at an earlier age.  相似文献   
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Solid-organ transplantation has become a widely accepted treatment modality for end-stage diseases. With the advent of newer and more potent immunosuppressive regimens, graft survival has improved, but at the expense of an increased risk for the development of infections secondary to bacterial, fungal, viral and parasitic pathogens. Prevention of such infectious complications with effective, well-tolerated and cost-effective antimicrobials would be ideal to improve the outcome of transplant patients. Cytomegalovirus is the most common cause of viral infections. Herpes simplex virus, Varicella-zoster virus, Epstein–Barr virus and others are also significant pathogens. Fungal infections are associated with the highest mortality rates. This review summarizes the most relevant data pertaining to the current understanding of infection prevention for solid-organ transplant recipients.  相似文献   
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In 2010, Coxiella burnetii was identified at a high prevalence in the placentas of Northern fur seals (Callorhinus ursinus) collected at a single rookery on St. Paul Island Alaska; an area of the United States where the agent was not known to be present. As contamination was hypothesized as a potential cause of false positives, but nothing was known about environmental C. burnetii in the region, an environmental survey was conducted to look for the prevalence and distribution of the organism on the island. While environmental prevalence was low, two strains of the organism were identified using PCR targeting the COM1 and IS1111 genes. The two strains are consistent with the organism that has been increasingly identified in marine mammals as well as a strain type more commonly found in terrestrial environments and associated with disease in humans and terrestrial animals. Further work is needed to elucidate information regarding the ecology of this organism in this region, particularly in association with the coastal environment.  相似文献   
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Asthma is a significant global public health issue. Severe asthma exacerbations can be triggered by environmental factors and require medical care from health services. Although it is known that fungal exposure may lead to allergic sensitization, little is understood about its impact on asthma exacerbations. This review aims to examine whether outdoor fungi play a significant role in child asthma exacerbations. Systematic search of seven electronic databases and hand searching for peer‐reviewed studies published in English, up to 31 August 2013. Inclusion criteria were study population aged <18 yr, diagnosis of asthma, attended a health service; outdoor fungi exposure was reported. Quality and risk of bias assessments were conducted. Due to significant heterogeneity, meta‐analysis was not conducted. Of the 1896 articles found, 15 were eligible. Findings were not consistent, possibly due to methodological variations in exposure classifications, statistical methods and inclusion of confounders. Cross‐sectional studies found no or weak associations. All but one time series studies indicated an association that varied between fungal species. Increasing evidence indicates that asthmatic children are susceptible to asthma exacerbations when exposed to outdoor fungal spores. There is limited understanding of the contributions of different fungal species. Research is needed to investigate interactions of outdoor fungi with pollen, air pollutants and respiratory viruses.  相似文献   
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Phaeohyphomycosis is a chronic subcutaneous fungal infection caused by dematiaceous fungi, commonly involving the extremities, which present as single or multiple lesions mimicking a benign tumor. Fine‐needle aspiration cytology (FNAC) is an easy method for the diagnosis of the lesion. Morphology of the fungus is characteristic with no difficulty for cytopathologist for identification; with a close differential diagnosis of Candida and Aspergillosis. The special stains like periodic acid schiff (PAS) highlights the fungus and the Masson Fontana confirm the melanin pigment and dematiaceous nature of the fungi. Liquid‐based cytology (LBC) preparation of the aspirated material was attempted, which is not usually performed on day to day basis. However, in our case the conventional smears were better for appreciating the fungal morphology.  相似文献   
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颞下窝真菌感染属于侵袭性真菌感染,临床少见,多发生于糖尿病、恶性肿瘤、烧伤或长期糖皮质激素治疗的患者,其病原菌源于鼻窦真菌[1-2]。近年来侵袭性真菌性鼻一鼻窦炎(invasive fungalrhino-sinusitis,IFRS)及其并发症在国内外的发病率明显上升,其主要并发症是眶内、翼腭窝、颞下窝及颅内真菌感染。其中,颞下窝真菌感染较侵袭到眶内或颅内的真菌感染更为少见[3-4]。现将我科诊治的2例颞下窝真菌感染患者的资料报告如下。  相似文献   
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