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Anne Maria Eikeset Andries Richter Erin S. Dunlop Ulf Dieckmann Nils Chr. Stenseth 《Proceedings of the National Academy of Sciences of the United States of America》2013,110(30):12259-12264
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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The importance of the in utero environment as a contributor to later life metabolic disease has been demonstrated in both human and animal studies. In this review, we consider how disruption of normal fetal growth may impact skeletal muscle metabolic development, ultimately leading to insulin resistance and decreased insulin sensitivity, a key precursor to later life metabolic disease. In cases of intrauterine growth restriction (IUGR) associated with hypoxia, where the fetus fails to reach its full growth potential, low birth weight (LBW) is often the outcome, and early in postnatal life, LBW individuals display modifications in the insulin-signaling pathway, a critical precursor to insulin resistance. In this review, we will present literature detailing the classical development of insulin resistance in IUGR, but also discuss how this impaired development, when challenged with a postnatal Western diet, may potentially contribute to the development of later life insulin resistance. Considering the important role of the skeletal muscle in insulin resistance pathogenesis, understanding the in utero programmed origins of skeletal muscle deficiencies in insulin sensitivity and how they may interact with an adverse postnatal environment, is an important step in highlighting potential therapeutic options for LBW offspring born of pregnancies characterized by placental insufficiency. 相似文献
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Oliver J. Gurney-Champion Dualta McQuaid Alex Dunlop Kee H. Wong Liam C. Welsh Angela M. Riddell Dow-Mu Koh Uwe Oelfke Martin O. Leach Christopher M. Nutting Shreerang A. Bhide Kevin J. Harrington Rafal Panek Kate L. Newbold 《International journal of radiation oncology, biology, physics》2018,100(2):306-316
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Calprotectin in cerebrospinal fluid of the HIV infected: a diagnostic marker of opportunistic central nervous system infection? 总被引:2,自引:0,他引:2
O Dunlop J N Bruun B Myrvang M K Fagerhol 《Scandinavian journal of infectious diseases》1991,23(6):687-689
The calprotectin level in the cerebrospinal fluid (CSF) of 15 HIV positive patients with symptoms from the central nervous system (CNS) was measured. All 5 patients with opportunistic infections had levels above the reference range and all 10 patients with HIV associated encephalopathy had levels within the reference range. Thus, the calprotectin level in CSF can be of diagnostic value in differentiating between HIV associated encephalopathy and opportunistic infection in the HIV positive patient with symptoms from the CNS. 相似文献
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Sawitzke AD Shi H Finco MF Dunlop DD Bingham CO Harris CL Singer NG Bradley JD Silver D Jackson CG Lane NE Oddis CV Wolfe F Lisse J Furst DE Reda DJ Moskowitz RW Williams HJ Clegg DO 《Arthritis and rheumatism》2008,58(10):3183-3191
OBJECTIVE: Osteoarthritis (OA) of the knee causes significant morbidity and current medical treatment is limited to symptom relief, while therapies able to slow structural damage remain elusive. This study was undertaken to evaluate the effect of glucosamine and chondroitin sulfate (CS), alone or in combination, as well as celecoxib and placebo on progressive loss of joint space width (JSW) in patients with knee OA. METHODS: A 24-month, double-blind, placebo-controlled study, conducted at 9 sites in the United States as part of the Glucosamine/Chondroitin Arthritis Intervention Trial (GAIT), enrolled 572 patients with knee OA who satisfied radiographic criteria (Kellgren/Lawrence [K/L] grade 2 or grade 3 changes and JSW of at least 2 mm at baseline). Patients with primarily lateral compartment narrowing at any time point were excluded. Patients who had been randomized to 1 of the 5 groups in the GAIT continued to receive glucosamine 500 mg 3 times daily, CS 400 mg 3 times daily, the combination of glucosamine and CS, celecoxib 200 mg daily, or placebo over 24 months. The minimum medial tibiofemoral JSW was measured at baseline, 12 months, and 24 months. The primary outcome measure was the mean change in JSW from baseline. RESULTS: The mean JSW loss at 2 years in knees with OA in the placebo group, adjusted for design and clinical factors, was 0.166 mm. No statistically significant difference in mean JSW loss was observed in any treatment group compared with the placebo group. Treatment effects on K/L grade 2 knees, but not on K/L grade 3 knees, showed a trend toward improvement relative to the placebo group. The power of the study was diminished by the limited sample size, variance of JSW measurement, and a smaller than expected loss in JSW. CONCLUSION: At 2 years, no treatment achieved a predefined threshold of clinically important difference in JSW loss as compared with placebo. However, knees with K/L grade 2 radiographic OA appeared to have the greatest potential for modification by these treatments. 相似文献
29.
William Dunlop Lachlan Hegarty Margaret Staples Michele Levinson Michael Ben‐Meir Katherine Walker 《Emergency medicine Australasia : EMA》2018,30(1):61-66
Objective
We aimed to evaluate patient perceptions of medical scribes in the ED and to test for scribe impacts on ED Net Promoter Scores, Press Ganey Surveys and other patient‐centred topics.Methods
Exploratory semi‐structured interviews were conducted in the ED during wait times after scribed consultations. Interview results were used to derive topics relating to scribes. Items addressing these topics from validated surveys were combined with items from widely used patient satisfaction questionnaires. Questionnaires were administered in the ED by face‐to‐face approach while patients were waiting for admission/discharge or test results. Patients and doctors were blinded to the purpose of the questionnaire. The survey evaluated for non‐inferiority of scribed consultations, using Net Promoter Scores, Press Ganey questions and questions specific to the presence of the scribe.Results
Patient interviews did not identify any negative views regarding the presence of scribes during consultations. Thematic saturation was achieved after seven interviews. Two hundred and fifty‐eight patients were approached to complete the questionnaire, and 215 participated (83%); 95 and 118 participants in the scribed and non‐scribed groups, respectively. There was no difference between scribed and non‐scribed consultations on the following measures of satisfaction: the Net Promoter Score, Press Ganey questions, quality of information received from doctors, communication, privacy concerns or inhibition about revealing private information and room crowding.Conclusion
We found no evidence that scribes reduce patient satisfaction during emergency consultations, nor prompt discomfort that might cause a patient to withhold information. 相似文献30.