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141.
HB Simonsen 《Canadian Metallurgical Quarterly》1978,30(6):241-252
Bone fragility and increased fat content in the liver of egg-laying hens are more often encountered in birds from traditional battery-cage systems than in those confined in other systems. By reviewing the relevant literature possible explanations of these phenomena are proposed. Clinical and pathological manifestations of the syndromes are described and a number of possible aetiological factors are evaluated. Bone fragility can be seen either as a general weakness of bone tissue or as a clinically manifest disease, Cage layer fatigue. It is concluded, that general restriction of the animal's possibilities to locomote and perform comfort movements are the most important aetiological factors. Fatty liver disease may be seen either as a pathological elevation of the liverfat content or it may be seen as a disease called Fatty liver haemorrhagic syndrome. Several factors may cause elevation of the liver fat content. The influence of restricted movement on the animals energy balance, however, like other behavioural disturbances seems to be the most important aetiological factors. It is concluded, that bone fragility and fatty liver in egg-laying hens are diseases caused by an inadequate environment and the restriction of essential behavioural patterns. 相似文献
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HB Verheul R Balázs JW Berkelbach van der Sprenkel CA Tulleken K Nicolay M van Lookeren Campagne 《Canadian Metallurgical Quarterly》1993,618(2):203-212
A retention model for ionizable compounds in micellar liquid chromatography is derived and verified. The use of the model for the prediction of retention is illustrated and appropriate optimization strategies for the separation of ionizable compounds in Micellar Liquid Chromatography are discussed. 相似文献
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Corey J.M. Wheeler B.C. Brewer G.J. 《IEEE transactions on bio-medical engineering》1996,43(9):944-955
Toward the goal of creating patterns of primary hippocampal neurons in low density culture, the authors investigated techniques to fabricate microminiature grids of organofunctional silanes on glassy surfaces. A new photoresist (PR) process, Selective Silane Removal (SSR), was developed and compared to two previously developed techniques which use PR and laser patterning. The grid patterns consisted of 27 combinations of path width, length, and intersection (node diameter). The background consisted of squares bounded for the paths. The best neuron patterning was observed on substrates produced by the SSR process where cytophilic aminosilane is uniformly deposited and selectively removed from the background. Controlling water during aminosilane deposition was critical to good neuronal growth and patterning. Oxygen plasma etching of background regions prior to cytophobic phenylsilane binding significantly reduced off-pattern cell growth. Up to 90% of somata grown on these substrates complied to the pattern, and an average of 77% of background regions were free of neurites or cells connected to the pattern. The highest laser energy density, 120 mJ/cm2, produced the best compliance on lased substrates, with an average of 35% of background regions free of connected cells and neurites, but considerable variation across the surface. On substrates with excellent patterning, compliance to nodes was found to be dependent on pattern dimensions, with 20-μm node diameters and 80-μm internodal path lengths increasing compliance 相似文献
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Differential influence of a selective melanocortin MC4 receptor antagonist (HS014) on melanocortin-induced behavioral effects in rats 总被引:1,自引:0,他引:1
AV Vergoni A Bertolini F Mutulis JE Wikberg HB Schi?th 《Canadian Metallurgical Quarterly》1998,362(2-3):95-101
We injected i.c.v. the natural agonist alpha-MSH (melanocyte-stimulating hormone) and the first selective melanocortin MC4 receptor antagonist HS014 (cyclic [AcCys11, D-Nal14, Cys18, Asp-NH(2)22]-beta-MSH(11-22) in rats and scored a number of behavioral effects which have been related to the melanocortic peptides. The results showed that HS014 (5 microg/rat) completely blocked alpha-MSH (3 and 5 microg/rat)-induced grooming, yawning and stretching. Penile erections induced by alpha-MSH were, however, only partially blocked by HS014. Injections of alpha-MSH decreased food intake in food-deprived rats, whereas HS014 increased food intake. When the peptides were given together, the food intake was similar to that of saline treated controls. Locomotion/exploration and resting were not influenced by either peptide. Our data show that exogenous beta-MSH decreases food intake, and that an endogenous central melanocortinergic inhibitory tone on feeding prevails which can be blocked with HS014, leading to an increase in food intake. Our data also provide evidence that grooming, stretching and yawning in rats may be mediated by the melanocortin MC4 receptor, whereas penile erections might perhaps be mediated by some other melanocortin receptor. 相似文献
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