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1.
BACKGROUND: Measurement of high concentrations of urine catecholamines and metanephrines is useful in diagnosing pheochromocytoma in humans. Stress increases catecholamine excretion in urine. HYPOTHESIS: Stress of a hospital visit increases urinary catecholamine and metanephrine excretion in dogs. ANIMALS: Fourteen clinically normal dogs, 2 dogs with pheochromocytoma. METHODS: Voided urine samples were collected by the owners 7 days before (t-7), during the hospital visit immediately after diagnostic procedures (t0), as well as 1 (t1) and 7 days (t7) after the hospital visit. Urine catecholamine and metanephrine concentrations were measured using high-pressure liquid chromatography and expressed as ratios to urine creatinine concentration. RESULTS: In client-owned dogs epinephrine and norepinephrine ratios at t0 were significantly higher compared with ratios at t7. Metanephrine and normetanephrine ratios at t-7, t0, and t1 did not differ significantly from each other; however, at t7 they were significantly lower compared to values at t-7. In staff-owned dogs no significant differences were detected among the different collecting time points for any variable. Metanephrine and normetanephrine ratios were significantly higher in client-owned dogs compared to staff-owned dogs at t-7, t0, and t1 but not at t7. CONCLUSIONS AND CLINICAL IMPORTANCE: Stress associated with a hospital visit and with the sampling procedure causes increases in urine catecholamine and metanephrine excretion. Urine collection for the diagnosis of pheochromocytoma probably should take place at home after adaptation to the sampling procedure.  相似文献   
2.
The growing set of fully-sequenced angiosperm genomes highlight the role of polyploidy in angiosperm evolution, and suggest that even the high level of importance we had already attributed to this mechanism was inadequate.  相似文献   
3.
Since 2007, the Open Access journal PLOS ONE has published 194,622 expert-reviewed scientific papers, including 85 related to the human food sciences such as food safety, general food science, and nutrition. Seventy-five of their corresponding authors had previously published. Their most cited articles in other journals were identified and citation counts compared against those earned by their PLOS ONE papers. No PLOS ONE food sciences paper has yet been cited more than an author's best effort in the field in other journals. More than half (38) of the 75 PLOS ONE papers studied remain uncited even by their own authors.  相似文献   
4.
Paterson  George B.  Smart  Gill  McKenzie  Paul  Cook  Sally 《Landscape Ecology》2019,34(12):2791-2805
Landscape Ecology - Habitat loss and fragmentation contribute significantly to pollinator decline and biodiversity loss globally. Conserving high quality habitats whilst restoring and connecting...  相似文献   
5.
Nitrous oxide (N2O) emissions make up a significant part of agricultural greenhouse gas emissions. There is an urgent need to identify new approaches to the mitigation of these emissions with emerging technology. In this short review four approaches to precision managements of agricultural systems are described based on examples of work being undertaken in the UK and New Zealand. They offer the opportunity for N2O mitigation without any reduction in productivity. These approaches depend upon new sensor technology, modeling and spatial information with which to make management decisions and interventions that can both improve agricultural productivity and environmental protection.  相似文献   
6.
This article considers the experiences of a Samoan female geographer undertaking community‐based field research in her home country, and identifies some lessons for researchers working in similar circumstances. The paper suggests that ethical behaviour in research is ‘place‐specific’, and there is therefore a need to employ culturally sensitive and ‘location‐specific’ methodologies when undertaking community‐based research fieldwork. For the lead researcher, growing up in Samoa played a significant role in gaining an understanding of a set of robust and effective procedures to evaluate citizens' resilience to climatic and other environmental challenges. Fluency in everyday and more formal local languages, and awareness of local differences, each with multi‐layered connections to local communities, understanding cultural nuances and practising respect for va tapuia [sacred space or relationships] protocols, together facilitated the process of knowledge acquisition and helped to confirm the validity of the conclusions derived from the study.  相似文献   
7.
Two trials involving housed cattle examined the effect of Co depletion and supplementation on immune status as assessed by the neutrophil function test which measures the ability of isolated neutrophils to kill the yeast Candida albicans. A third trial investigated the extent to which Co status influenced the severity of Ostertagia ostertagi infection. In the first two trials liveweight gains were unaffected until some 40-60 weeks on the low dietary Co intake despite very low serum vitamin B12 values being recorded after 10 weeks. However, the immune status as measured by the neutrophil function test was reduced within 10 weeks of commencing the low Co diet. On administration of Ostertagia ostertagi larvae, Co-depleted cattle showed a greater weight loss than Co-supplemented cattle but showed no difference in the length of the prepatent period, worm egg production or serum gastrin and pepsinogen concentrations. After anthelmintic treatment both groups showed a similar response. It is postulated that the lowered immune response of Co-depleted cattle resulted in the greater severity of the Ostertagia ostertagi infection.  相似文献   
8.
Abstract – Strontium/Calcium (Sr/Ca) and Barium/Calcium (Ba/Ca) ratios were measured in 60 otoliths of the French Polynesian flagtail Kuhlia malo. Both elemental ratios were needed to correctly distinguish residence in marine, brackish and fresh water. High Sr/Ca and low Ba/Ca around the nucleus of all otoliths provided evidence of marine residency during the early life of all individuals. At about 0.5 mm from the core, Ba/Ca increased rapidly and remained high in all otoliths. High and unstable Sr/Ca ratios were attributed to estuarine residency, whereas low and stable Sr/Ca ratios were attributed to freshwater residency. These chemical signatures inferred that following recruitment to rivers, some fish remained in the estuary, while others moved upstream. Some individuals shared their time between fresh and brackish waters later in life. The findings of this study have important implications for the protection of nearshore, brackish and freshwater environments for the conservation of this French Polynesian diadromous species.  相似文献   
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10.
To better understand the interaction between Mycoplasma bovis and its bovine host, we have characterized the immune response generated during an experimental lung infection with M. bovis. Proliferation ([3H]-thymidine blastogenesis) and Th1/Th2 cytokine production were used to monitor peripheral cellular immune responses. Flow cytometry analysis was used to determine T-cell subset activity by CD25 expression. Humoral immune response was monitored by the identification of antigen-specific IgG1 and IgG2 isotypes over time. Herein, we show that M. bovis antigen stimulates activation of CD4+ and CD8+ cells in vitro in a manner consistent with memory, and that gammadelta-T cells are activated by antigen in a manner consistent with innate immunity. In addition, the percentage of cells producing IFN-gamma during recall response is equal to that of IL-4 producing cells. Serological analysis shows M. bovis stimulates increased production of antigen-specific IgG1 while very little IgG2 is produced. We therefore submit that experimental lung infection of cattle with M. bovis results in a Th2-skewed immune response.  相似文献   
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