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101.
G Brem B Brenig B Salmons E Wolf M Müller V Erfle W H Günzburg E Dahme 《Tier?rztliche Praxis》1991,19(4):345-350
Pronuclear microinjection was used to produce transgenic mice harboring gene constructs, in which 110 base pairs (WAP1) or 2.4 kilobases (WAP2) of the 5' flanking sequences of the whey acidic protein (WAP) gene were fused to human growth hormone (hGH)-coding sequences. Female WAP-hGH transgenic mice expressed the transgenes in the mammary gland, the expression of the WAP2-hGH transgene mirroring that of the endogenous WAP gene. When other organs were examined, high level expression of hGH was observed in the brains of WAP2-hGH transgenic mice. Using in situ hybridization and immunohistochemistry, hGH expression from the transgene was seen to occur specifically in Bergmann glia cells. While normally neither WAP nor hGH is expressed in this type of cell, it appears that a combination of the regulatory region of the WAP gene and the hGH structural gene results in a novel tissue specificity in Bergmann glia cells. 相似文献
102.
103.
Clifford L.K. Robinson Beatrice Proudfoot Christopher N. Rooper Douglas F. Bertram 《水产资源保护:海洋与淡水生态系统》2021,31(10):2855-2869
- The Pacific sand lance (Ammodytes personatus) is a key forage species for many commercially important fish (e.g. salmon and groundfish), marine birds, and whales found in nearshore coastal waters of British Columbia, Canada.
- Sand lance lack a swim bladder and have a requirement for low-silt, medium-coarse sandy sea-bed habitat for burying. Little information is available describing the distribution of burying habitat, partly because there are no commercial fisheries for A. personatus in British Columbia.
- This information is required by habitat and wildlife managers to identify and protect uncommon patches of burying habitats from detrimental activities, including dredging, infilling, and oil spills.
- In this study, habitat distribution results from five suitability modelling algorithms were evaluated: maximum entropy, generalized linear model, generalized additive model, random forest, and an ensemble model of the latter three.
- The maximum entropy model had the highest performance score (area under the receiver operator characteristic curve was 0.78) and was selected as the model that most accurately identified the presence of suitable A. personatus burying habitat.
- Model results indicate that suitable burying habitat is primarily influenced by derived sea-bed substrate, distance to estuary, distance to sand-gravel beaches, and bottom sea temperature.
- Overall, the spatial modelling identified only 105 km2 of highly suitable sand lance burying habitat, or 2.6% of the study area (0–150 m), primarily in Haro Strait, along the east coast of Vancouver Island, and in northern regions of the strait near Cortes, Savary, and Harwood islands.
- Identification of this uncommon and patchy burying habitat will contribute to the ongoing conservation of an important coastal prey species.
104.
Geoff Bertram 《Asia Pacific viewpoint》2006,47(1):1-13
Abstract: The papers collected in this volume were originally presented at a conference in February 2004, on the theme ‘Beyond MIRAB: The Political Economy of Small Islands in the Twenty‐First Century’. Several of the papers in the collection point towards the emergence of a new three‐way taxonomy of small‐island socioeconomic formations, comprising MIRAB, PROFIT and SITE ideal‐types. The key economic flows in the first are remittances and aid; in the second, jurisdictionally‐related flows such as tax‐haven and money‐laundering transactions; and in the third, tourism revenues. All three ideal‐types correspond to potentially sustainable temporary equilibria, but in all cases the existing set‐up is path‐dependent, and subject to regime switch if disturbed. Conceptualisation of the small‐island world as a field of multiple equilibria and path dependence points to the future importance of event studies by island researchers. The collection includes also new research on the theory of remittances, and case studies of the MIRAB process and the transnational migrant diaspora. 相似文献
105.
106.
107.
Bertram TH Perring AE Wooldridge PJ Crounse JD Kwan AJ Wennberg PO Scheuer E Dibb J Avery M Sachse G Vay SA Crawford JH McNaughton CS Clarke A Pickering KE Fuelberg H Huey G Blake DR Singh HB Hall SR Shetter RE Fried A Heikes BG Cohen RC 《Science (New York, N.Y.)》2007,315(5813):816-820
We present a statistical representation of the aggregate effects of deep convection on the chemistry and dynamics of the upper troposphere (UT) based on direct aircraft observations of the chemical composition of the UT over the eastern United States and Canada during summer. These measurements provide unique observational constraints on the chemistry occurring downwind of convection and the rate at which air in the UT is recycled. These results provide quantitative measures that can be used to evaluate global climate and chemistry models. 相似文献
108.
Hanne Christine Bertram Bent Ole Petersen Jens ? Duus Mogens Larsen Birgitte-Marie L Raun Niels Bastian Kristensen 《Acta veterinaria Scandinavica》2009,51(1):25
Background
It is unknown which metabolites are responsible for propylene glycol (PG)-induced toxicosis, and a better understanding of the underlying mechanisms explaining incidences of abnormal behaviour of dairy cows fed PG is therefore needed.Methods
The study included three cows of which one developed PG toxicosis. In order to investigate how the metabolism of PG differed in the cow developing toxicosis, proton nuclear magnetic resonance (NMR) spectroscopy was applied on ruminal fluids and blood plasma samples obtained before and after feeding with PG.Results
PG toxicosis was characterized by dyspnea and ruminal atony upon intake of concentrate containing PG. The oxygen saturation of arterial blood haemoglobin and the oxygen pressure in arterial blood decreased along with the appearance of the clinical symptoms. NMR revealed differences in plasma and ruminal content of several metabolites between the cow responding abnormally to PG and the two control cows.Conclusion
It is concluded that PG-toxicosis is likely caused by pulmonary vasoconstriction, but no unusual metabolites directly related to induction of this condition could be detected in the plasma or the ruminal fluid. 相似文献109.
Bertram HC Kristensen M Østdal H Baron CP Young JF Andersen HJ 《Journal of agricultural and food chemistry》2007,55(6):2342-2348
Water-binding properties of myofibrils extracted from porcine muscle, and added hemoglobin with and without exposure to H2O2, were characterized using low-field proton NMR T2 relaxometry. The effects of pH and ionic strength in the samples were investigated as pH was adjusted to 5.4, 6.2, and 7.0 and ionic strength was adjusted to 0.29, 0.46, and 0.71 M, respectively. The formation of dityrosine as a measure of oxidative protein cross-linking revealed a significant increase in dityrosine concentrations upon H2O2 activation. The formation of dityrosine was strongly pH-dependent and increased with decreasing pH. In addition, increased levels of thiobarbituric acid reactive substances were observed upon addition of H2O2, implying that lipid oxidation was enhanced, however, with a different oxidation pattern as compared to the myofibrillar proteins. Low-field NMR relaxation measurements revealed reduced T2 relaxation times upon H2O2 activation, which corresponds to reduced water-holding capacity upon oxidation. However, a direct relationship between degree of oxidation and T2 relaxation time was not observed with various pH values and ionic strengths, and further studies are needed for a complete understanding of the effect of oxidation on myofibrillar functionality. 相似文献
110.
Herbrand K Hammerschmidt FJ Brennecke S Liebig M Lösing G Schmidt CO Gatfield I Krammer G Bertram HJ 《Journal of agricultural and food chemistry》2007,55(19):7874-7878
This study describes the identification of six allyl esters in a garlic cheese preparation and in a commercial cream cheese. The extracts were prepared by liquid/liquid extraction and concentrated by the SAFE process. The identification of the allyl esters of acetic, butyric, hexanoic, heptanoic, octanoic, and decanoic acids is based on the correlation of their mass spectrometric data and chromatographic retention time data obtained from the extracts with those of authentic standards. In addition to the gas chromatography (GC)/mass spectrometry analysis, the flavor ingredients were characterized by GC sniffing by a trained flavorist. Some of the esters were isolated by preparative GC. 相似文献