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131.
132.
HB Goldman RS Israeli JL Lerner RS Hollabaugh MS Steiner 《Canadian Metallurgical Quarterly》1998,52(6):1073-1078
In this investigation, the presence of NKA-immunoreactive substances was determined in pineal glands from intact, castrated and castrated, testosterone-treated male rats. The effect of environmental light, melatonin treatment and superior cervical ganglionectomy on pineal NKA-immunoreactive substances was also investigated. The results obtained show that NKA is present in measurable amounts in the rat pineal, and NPK is probably also present, Orchidectomy was followed by an increase in the content of NKA-immunoreactive substances in the pineal gland. The replacement treatment with testosterone propionate in castrated rats blocked this effect. NKA-immunoreactive substances were not significantly different quantitatively in pineals from rats killed under light or under darkness. The removal of the superior cervical ganglia was followed by a significant increase in the NKA-immunoreactive substance content in the pineal gland of male rats. These results indicate that NKA and other tachykinins are present in the pineal gland of the male rat, and they seem to be regulated by gonadal hormones and the innervation originated from the superior cervical ganglia. 相似文献
133.
M Geldmacher v Mallinckrodt A Zober J Dumbach JH Geldmacher L Lautenbach G Machbert G Reinhardt G Schaidt B Schellmann W Schütz HB Wuermeling P Zink 《Canadian Metallurgical Quarterly》1976,78(2):97-120
11 cases of rapid central death following combination of sublethal doses of alcohol and sedativa are presented with case-history, histology, alcohol-concentrations and toxicological findings. 相似文献
134.
The role of the sinoatrial ring bundle (SARB) in internodal conduction was examined by the microelectrode technique in excised rabbit hearts. The spread of the sinus impluse to the surrounding tissues was shown to proceed anteriorly toward the right branch of the crista terminalis significantly faster than toward the other direction. Thus the right SARB and the right branch of the crista terminalis close to the sinus node were the earliest areas excited by the sinus impulse in the areas surrounding the sinus node. It was further shown that the activation sequence does not initiate from the right SARB to the right branch of the crista terminalis via the junction of these two structures. Cutting the SARB did not produce any delay in conduction from the sinus node to the atrioventricular (AV) node. The conduction velocity measured at the endocardial surface by two microelectrodes has proved that conduction in the crista terminalis was significantly faster than in the SARB. The upstroke of the action potential from the crista terminalis was also steeper than that from the SARB. These results suggest that the SARB is not the main route for impulse propagation from the sinus node to the AV node; the fastest internodal conduction therefore takes place with wide wave fronts, along the crista terminalis. 相似文献
135.
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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137.
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
138.
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140.
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