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For the fifth year, BMC Ecology is proud to present the winning images from our annual image competition. The 2017 edition received entries by talented shutterbug-ecologists from across the world, showcasing research that is increasing our understanding of ecosystems worldwide and the beauty and diversity of life on our planet. In this editorial we showcase the winning images, as chosen by our Editorial Board and guest judge Chris Darimont, as well as our selection of highly commended images. Enjoy!  相似文献   
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Qualitative and quantitative differences among the constituents in various fennel (Foeniculum vulgare Mill., family Apiaceae) teas prepared by classical infusion, microwave decoction, and dissolution are reported. Different commercial starting materials, such as fruit (unbroken and crushed), four herbal teas, and two instant herbal teas were evaluated. Chlorogenic acid (1), quercetin-3-O-beta-D-glucuronide (2), p-anisaldehyde (3), and trans-anethole (4) were identified by HPLC-DAD and HPLC-MS as constituents of fennel teas. No coumarins, which are characteristic constituents of plants of Apiaceae family, were found. Trans-anethole (4), the main constituent of the essential oil, was present in all teas. In addition p-anisaldehyde (3), a degradation product of trans-anethole, was also identified in all teas with the exception of two samples. Chlorogenic acid (1) and quercetin-3-O-beta-D-glucuronide (2) were also present in all teas. In addition, minor unidentified flavonol constituents were found in two teas. Quality, activity, and safety of the content of the investigated preparations are also discussed.  相似文献   
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The efficiency of two-dimensional homonuclear (1)H--(1)H correlated spectroscopy and two-dimensional reverse heteronuclear shift correlation spectroscopy (i.e., heteronuclear multiple quantum correlation) in characterizing and evaluating the relative content of herbal extract constituents is demonstrated. These experiments are able to fully assign the proton and carbon resonances of all three classes of constituents present in dried commercial extract of St. John's wort, that is, flavonols, phloroglucinols, and naphthodianthrones, with particular regard to the very unstable phloroglucinols. In addition, shikimic and chlorogenic acids, sucrose, lipids, polyphenols, and traces of solvents of the extractive process (methanol) were also identified. These experiments can be considered to be a very simple and fast analytical method for determining the quality and stability of the titled commercial extract. They represent a generally applicable technique for a rapid screening and a specific measurement of other commercial phytochemicals or, in selected cases, an alternative to the classical analytical techniques such as high-performance thin-layer chromatography, high-performance liquid chromatography, capillary gas chromatography, and electrophoresis.  相似文献   
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This study focused on the expression of somatotropic axis genes in the skeletal muscle of dairy cattle. A slow-release recombinant bovine growth hormone (GH) (rbGH) formulation was administered to 5 cows, and saline solution (control) was administered to another 5 cows every 2 wk for a total of 10 wk, starting from the peak of lactation. Tissue and blood samples were collected on days 2 and 14 after each rbGH injection. As target genes insulin-like growth factor (IGF)-1, IGF-2, IGFBPs (1, 2, 3, 4, 5, 6), acute labile subunit (ALS), IGF-1 receptor (IGF-1R), GH receptor (GHR), and the known GHR 5′-UTR variants were selected as target genes, and their relative expression was measured using real-time polymerase chain reaction. In GH-treated cows, an increase in expression was observed for GHR 5′-UTR variant 1I on day 14 (P < 0.05), whereas a significant down-regulation of GHR (P < 0.05) was found after comparing values of treated cows between day 2 and day 14. However, only IGF binding proteins (BP)-5 was found to be appreciably up-regulated in GH-treated cows (P < 0.001), which may indicate the importance of this gene in the overall molecular response to GH administration. Our study indicated that GH treatment did not affect the expression of most somatotropic axis genes, despite the marked increase in GH and IGF-1 in blood (P < 0.001). Nor did it have a large impact on the proportion of GHR 5′-UTR variants in the skeletal muscle of lactating cows. Finally, although we observed a significant variation in the expression of some genes, it would appear that the differences between GH-treated cows and controls were not great enough to be considered as reliable indirect indicators of GH treatment in dairy cattle.  相似文献   
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Journal of Pest Science - Classical biological control, i.e., the introduction of natural enemies from an invasive pest’s area of origin, has been proposed repeatedly to control the spotted...  相似文献   
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Aortic occlusion is a rare vascular disorder in the dog. This report describes the clinical feature of an aged Boxer with complete occlusion of the abdominal aorta caused by an intraluminal thrombus. Angiography evidenced a collateral circulation, represented by the internal thoracic artery, the cranial epigastric artery and the caudal epigastric artery, providing adequate blood flow to the pelvis and pelvic limbs. This vascular network has only recently been recognised as one of the major collateral pathways for arterial blood supply to the pelvis and lower extremities in humans with chronic aorto-iliac occlusive disease (CAOD). Furthermore, a femoral artery Doppler waveform, characterised by low amplitude, a monophasic systolic wave with blunted parabolic flow profile and a small spectral window, peculiar to humans with CAOD, is documented for the first time in a dog with aortic occlusion.  相似文献   
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