102 resultados para 327.1746


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Connections between environmental and cultural changes are analysed in Estonia during the past c. 4,500 years. Records of cereal-type pollen as (agri)cultural indices are compared with high-resolution palaeohydrological and annual mean temperature reconstructions from a selection of Estonian bogs and lakes (and Lake Igelsjon in Sweden). A broad-scale comparison shows increases in the percentage of cereal-type pollen during a decreasing trend in annual mean temperatures over the past c. 4,300 years, suggesting a certain independence of agrarian activities from environmental conditions at the regional level. The first cereal-type pollen in the region is found from a period with a warm and dry climate. A slow increase in pollen of cultivated land is seen around the beginning of the late Bronze Age, a slight increase at the end of the Roman Iron Age and a significant increase at the beginning of the Middle Ages. In a few cases increases in agricultural pollen percentages occur in the periods of warming. Stagnation and regression occurs in the periods of cooling, but regression at individual sites may also be related to warmer climate episodes. The cooling at c. 400-300 cal b.p., during the 'Little Ice Age' coincides with declines in cereal-type and herb pollen curves. These may not, however, be directly related to the climate change, because they coincide with war activities in the region.

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The illegal use of anabolic substances in the meat producing industry is an ongoing problem due to the continual production of new synthetic compounds and/or the practice of low-level cocktail administration to avoid detection by the surveillance schemes of EU member states National Plan surveillance systems.

We present a highly sensitive reporter gene assay and sample extraction procedure based on a two step solid phase extraction and high performance liquid chromatography, developed for the detection of glucocorticoid abuse in bovine urine. The assay is capable of detecting compounds with glucocorticoid bioactivity and is extremely sensitive with an EC50 of 0.79 ng mL-1 for dexamethasone. New or unknown compounds with glucocorticoid bioactivity and low-level cocktail mixtures are detectable by this assay.

Cross-reactivity data for a range of 11ß-hydroxyglucocorticoids has been provided. This assay shows low interference from the 11-keto prohormones and other steroidal hormones. The assay may be suitable for application in other matrices such as hair. In conclusion this screening assay offers advantages over existing analytical techniques.

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This review article reveals a long-standing gender bias in academic and policy research on adolescent pregnancy, which has led to the neglect of adolescent men's perspectives. The review summarizes the available literature on adolescent men's attitudes in relation to pregnancy occurrence and pregnancy outcomes in the context of addressing three questions: (1) What are adolescent men's attitudes to an adolescent pregnancy? (2) What are adolescent men's attitudes in relation to pregnancy outcomes? (3) What explanations are offered for the identified attitudes to adolescent pregnancy and resolution? The review establishes a foundation for future quantitative and qualitative research on adolescent men's perspectives. It emphasizes that a greater understanding of adolescent men's perspectives could lead to a re-framing of adolescent pregnancy away from being seen solely as a woman's issue. Furthermore, it is argued that the inclusion of adolescent men would lead to more effective adolescent pregnancy prevention and counseling programmes.

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Background: We investigated if minimizing bowel manipulation and mesenteric traction using the retroperitoneal approach in open abdominal aortic aneurysm (AAA) repair preserves splanchnic perfusion, as measured by gastric tonometry, and reduces the systemic inflammatory response and dysfunction of the various organs.