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41.
Norway was requested by the International Whaling Commission (IWC) to explore the use of high-velocity projectiles to replace cold harpoon as killing device for minke whales (Anon 1980). Tests of suitable high-velocity projectiles for minke whales were therefore initiated in 1982 as part of a wider project with the purpose of studying alternative killing methods to the traditional cold harpoon used in the Norwegian minke whale hunt until 1984 (Øen 1995). The results of the trials have previously been presented in unpublished reports to the IWC (Øen 1982, 1983, 1992). 相似文献
42.
43.
Anti-complement effects of lactoferrin-derived peptides 总被引:2,自引:0,他引:2
Samuelsen Ø Haukland HH Ulvatne H Vorland LH 《FEMS immunology and medical microbiology》2004,41(2):141-148
Lactoferrin is an important biological molecule with many functions such as modulation of the inflammatory response, iron metabolism and antimicrobial defense. One effect of lactoferrin is the inhibition of the classical complement pathway. This study reports that antimicrobial peptides derived from the N-terminal region from both human and bovine lactoferrin, lactoferricin H and lactoferricin B, respectively, inhibit the classical complement pathway. No inhibitory effect of these peptides was observed on the alternative complement pathway in an AP50 assay. However, lactoferricin B reduced the inhibitory properties of serum against Escherichia coli in a concentration dependent manner. These results suggest that the N-terminal region of lactoferrin is the important part in the inhibition of complement activation and that these peptides possess other important properties than their antimicrobial effect. 相似文献
44.
Andersen GØ Skomedal T Enger M Fidjeland A Brattelid T Levy FO Osnes JB 《American journal of physiology. Heart and circulatory physiology》2004,286(4):H1354-H1360
We studied molecular and functional characteristics as well as hormonal regulation of the Na-K-2Cl cotransporter (NKCC) in the isolated rat heart and cardiomyocytes. NKCC activity was measured as bumetanide-sensitive (86)Rb(+) influx in isolated perfused rat hearts and isolated cardiomyocytes. Stimulation of alpha(1)-adrenoceptors (AR) by phenylephrine (30 microM) increased (86)Rb(+) influx. The NKCC inhibitor bumetanide (50 microM) reduced the response to phenylephrine by 45 +/- 13% (n = 12, P < 0.01). PD-98059 (10 microM), an inhibitor of the activation of the mitogen-activated protein kinases extracellular signal-regulated protein kinase 1 and 2 (ERK1/2), reduced the total response to phenylephrine by 51 +/- 13% (n = 10, P < 0.01) and eliminated the bumetanide-sensitive component, indicating that alpha(1)-AR mediated stimulation of NKCC is dependent on activation of ERK1/2. Inhibitors of protein kinase C or phosphatidylinositol 3-kinase had no effect. The presence of NKCC mRNA and protein was demonstrated in isolated rat cardiomyocytes. Phosphorylation of NKCC after alpha(1)-AR stimulation was shown by immunoprecipitation of the phosphoprotein from (32)P(i) prelabeled cardiomyocytes. Increased phosphorylation of the NKCC protein was also abolished by PD-98059. We conclude that the NKCC is present in rat cardiomyocytes and that ion transport by the cotransporter is regulated by alpha(1)-AR stimulation through phosphorylation of this protein involving the ERK pathway. 相似文献
45.
Anthocyanin from strawberry (Fragaria ananassa) with the novel aglycone, 5-carboxypyranopelargonidin 总被引:1,自引:0,他引:1
An anthocyanin, 1, with the novel 4-substituted aglycone, 5-carboxypyranopelargonidin, was isolated in small amounts from the acidified, methanolic extract of strawberries, Fragaria ananassa Duch., by preparative HPLC after purification by partition against ethyl acetate, Amberlite XAD-7 and Sephadex LH-20 column chromatography. It was identified mainly by 2D NMR spectroscopy and electrospray LC-MS as the 3-O-beta-glucopyranoside of 5-carboxy-2-(4-hydroxyphenyl)-3,8-dihydroxy-pyrano[4,3,2-de]-1-benzopyrylium, an anthocyanidin which is homologous to 5-carboxypyranomalvidin (vitisidin A) reported in red wines and 5-carboxypyranocyanidin recently isolated from red onions. By comparison of UV-Vis absorption spectra, 1 showed in contrast to 2, pelargonidin 3-O-beta-glucopyranoside, a local absorption peak around 360 nm, a hypsochromic shift (8 nm) of the visible absorption maximum, and lack of a distinct UV absorption peak around 280 nm. The similarities between the absorption spectra of 1 in various acidic and neutral buffer solutions implied restricted formation of the instable colourless equilibrium forms, which are typical for most anthocyanins in weakly acidic solutions. The molar absorptivity (epsilon) of 1 varied little with pH contrary to similar values of for instance the major anthocyanin in strawberry, 2. However, 2 revealed higher epsilon-values than 1 at all pH values except 5.1. At pH 5.1, the epsilon-value of 1 (6250) was nearly four times the corresponding value of 2 (1720), which showed the potential of 5-carboxypyranopelargonidin derivatives as colorants in solutions with pH around 5. The colours of 1 and 2 in buffered solutions with pH 1.1 and pH 6.9 have been described by the CIELAB coordinates h(ab) (hue angle), C* (chroma), and L* (lightness). 相似文献
46.
Øien AH 《Bulletin of mathematical biology》2004,66(1):1-46
Attempts are presented of an analogue modelling of Daphnia responses to various influences and stimuli, as distribution of
food and of predators. An aim of the study is to examine to what extent a statistical-mechanical approach may be useful as
a tool in modelling of Daphnia swarms behaviour. In the modelling we follow a line close to test particle studies in physical
sciences. A generalized kinetic equation of what we shall call daphnicles is derived. The modelling incorporates individual characteristics of daphnicles, as position, velocity, degree of food saturation
and responses daphnicles have to outside influences. Each daphnicle we assume responds to some stimuli in ordered ways and
to others in stochastic ways, and the degree or strength of reactions depends on the density of all daphnicles, the density
of food available, the saturation level of daphnicles and the threat level in the environment, or background, the daphnicles
are living on. Some fluid equations of daphnicle swarms are subsequently derived from the basic equation, and solutions are
given of the model-equations, including a food distribution equation, in some particular cases that show peculiarities in
reactions of daphnicles to food, degree of saturation and to threat, when these are acting alone, and in combination. The
modelling results may be compared to results of laboratory experiments of Daphnia behaviour that soon will be performed. 相似文献
47.
48.
Gjøstein H Holand Ø Weladji RB 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2004,137(4):292-656
Milk yield and composition of major milk constituents were measured in captive, nursing reindeer. Registration of milk production was performed during two successive lactations (2001 and 2002). The milk yield was significantly affected by week of lactation (P<0.001) and by individual (P<0.001). The lactation curve had an asymmetrical peak 3 weeks postpartum and the milk yield at peak lactation was 983 g/day (range 595-1239). The length of lactation varied from 24 to 26 weeks and average total milk production was 99.5 kg. From peak lactation the milk production decreased linearly (P<0.001) until milk production was terminated. Mean values for content of major milk constituents were 15.5% fat, 9.9% protein and 2.5% lactose. The content of fat and protein increased markedly with the lactation stage (P<0.001), while lactose showed a slight decrease (P<0.001). The milk composition was significantly affected by stage of lactation (P<0.001). There was a marginally significant decrease in protein:fat ratio (P=0.06) as protein was substituted by fat with stage of lactation. The caloric value of the milk averaged 8.7 kJ/g and increased significantly with the stage of lactation (P<0.001). The overall increase in milk gross energy content during lactation was 67.6%. The energy output averaged 7996 kJ/day at peak lactation and decreased significantly during the course of lactation (P=0.002). 相似文献
49.
Minna Ruokonen Laura Kvist Tomas Aarvak Juha Markkola Vladimir V. Morozov Ingar J. Øien Eugeny E. Syroechkovsky Jr. Petteri Tolvanen Jaakko Lumme 《Conservation Genetics》2004,5(4):501-512
The lesser white-fronted goose is a sub-Arctic species with a currently fragmented breeding range, which extends from Fennoscandia to easternmost Siberia. The population started to decline at the beginning of the last century and, with a current world population estimate of 25,000 individuals, it is the most threatened of the Palearctic goose species. Of these, only 30–50 pairs breed in Fennoscandia. A fragment of the control region of mtDNA was sequenced from 110 individuals from four breeding, one staging and two wintering areas to study geographic subdivisions and gene flow. Sequences defined 15 mtDNA haplotypes that were assigned to two mtDNA lineages. Both the mtDNA lineages were found from all sampled localities indicating a common ancestry and/or some level of gene flow. Analyses of molecular variance showed significant structuring among populations (
ST 0.220, P < 0.001). The results presented here together with ecological data indicate that the lesser white-fronted goose is fragmented into three distinctive subpopulations, and thus, the conservation status of the species should be reconsidered. 相似文献
50.
Mechanisms of hydrazine toxicity in rat liver investigated by proteomics and multivariate data analysis 总被引:1,自引:0,他引:1
A proteomics approach combined with multivariate data analysis was used to examine the hepatotoxic effect of hydrazine in 30 male Sprague Dawley rats, assigned to four treatment groups and two control groups. Liver samples from the individual animals were resolved by two-dimensional differential gel electrophoresis (2-D DIGE) and protein patterns from the 2-D gels were analyzed by principal component analysis (PCA) and partial least squares regression (PLSR). The PCA plot was able to describe the variation in the protein expression related to dose and time, by separation or clustering of different animal groups. PLSR followed by variable selection (Jack-knifing) was used to select proteins that varied significantly in relation to the dose related response of the hydrazine treatment. The 10 up-regulated and 10 down-regulated proteins with highest rank in the PLSR model were identified by mass spectrometry. Hydrazine treatment induced altered expression of proteins related to lipid metabolism, Ca(2+) homeostasis, thyroid hormone pathways and stress response. Several of the identified proteins have not previously been implicated in hydrazine toxicity and may thus be regarded as new potential biomarkers of induced liver toxicity. 相似文献