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51.
Insulin and glucose in neonatal calves after peroral insulin and intravenous glucose administration.
Effects of peroral insulin on plasma concentrations of immunoreactive insulin (IRI) and glucose in newborn calves were studied. Bovine insulin was administered in amounts of 0.5 mg/kg body weight immediately preceding first colostrum. Thereafter, neither an increased IRI response nor a lowering of blood glucose level were observed, indicating that insulin was either not absorbed from the intestine or possibly retained in the liver. Feeding of whole milk was followed by a higher rise in IRI and glucose concentrations than feeding of colostrum after po insulin. However, when compared with 1-3-month old calves, IRI responses to feeding and to iv infused glucose were markedly smaller on the first and second day of life respectively, while glucose responses were similar. This indicates that insulin secretory mechanisms are not fully developed in the newborn calf. 相似文献
52.
Ingrid Holst Olsen Nanna Holt Seppo W. Langer Jane P. Hasselby Henning Gr?nb?k Jens Hillings? Masti Mahmoud Morten Ladekarl Lene H. Iversen Andreas Kj?r Birgitte H. Federspiel Ulrich Knigge 《PloS one》2015,10(2)
BackgroundAppendiceal goblet cell carcinoids (GCCs) exhibit neuroendocrine and adenocarcinoma features.ResultsMedian age for f/m was 59/58 years, respectively, and similar for localized and disseminated disease. At diagnosis 54 patients had localized appendiceal disease (f/m: 29/25). According to TNM 24% had Stage I, 70% had Stage II and 6% had Stage III. Twenty-nine patients had disseminated disease (f/m: 27/2). Chromogranin A, synaptophysin and p53 were positive in >90%. Serotonin was positive in 70%. Median Ki67 index was 32% (6-75%) and higher in Tang group C (50%) compared to group A (30%; p<0.0001), and group B (30%; p<0.004). All patients had surgery. Sixty-three (76%) had radical resections including all patients with localized disease. Median OS was 83 months. The 1-, 5- and 10-year survival rates were 90%, 58%, and 38%, respectively. For localized disease OS was 164 months and 1-, 5- and 10-year survival rates were 100%, 80%, and 55%, respectively. For disseminated disease OS was 19 months and 1-, 5- and 10-year survival rates were 73%, 18% and 6%, respectively. The 1-, 5- and 10 year-survival rates for f/m were 87%/96%, 49%/76% and 31%/57%, respectively (p = 0.02). According to the Tang classification group A, B, and C OS was 118, 83 and 20 months, respectively (p = 0.0002).ConclusionThe Tang classification was found to be a significant prognostic factor, while the Ki67 index was not. Localized GCCs occurred equally in males and females, while disseminated GCCs were mostly seen in females. Median age of patients with localized disease and disseminated disease was identical. Cox regression analysis found Stage IV, focally positive synaptophysin and non-radical surgery as strongest negative prognostic factors. 相似文献
53.
Pascal Weigold Alexander Ruecker Tina Loesekann-Behrens Andreas Kappler 《Geomicrobiology journal》2016,33(5):426-440
Little is known about the potential activity of microbial communities in hypersaline sediment ecosystems. Ribosomal tag libraries of DNA and RNA extracted from the sediment of Lake Strawbridge (Western Australia) revealed bacterial and archaeal operational taxonomic units (OTUs) with high RNA/DNA ratios providing evidence for the presence of ‘rare’ but potentially “active” taxa. Among the ‘rare’ bacterial taxa Halomonas, Salinivibrio and Idiomarina showed the highest protein synthesis potential. Rare but ‘active’ archaeal OTUs were related to the KTK 4A cluster and the Marine-Benthic-Groups B and D. We present the first molecular analysis of the microbial diversity and protein synthesis potential of rare microbial taxa in a hypersaline sediment ecosystem. 相似文献
54.
The reaction of halflanthanidocene aryloxides CpR′Ln(OArtBu,R)2 (Ln = Y, La, Lu; CpR′ = C5Me5, C4Me4H; R = H, Me) and halflanthanidocene alkoxides [(C5Me5)Ln(OCH2CMe3)2]2 (Ln = Y, Lu) with trimethylaluminum (TMA) was investigated. Monomeric CpR′Ln(OArtBu,R)2, derived from the ortho-tBu-substituted OC6H2tBu2-2,6-R-4 (R = H, Me) ligands, form mono(tetramethylaluminate) complexes CpR′Ln(OArtBu,R)(AlMe4) for the smaller lanthanide metal centers yttrium and lutetium. Such an [aryloxide] → [aluminate] ligand exchange was not observed at the larger lanthanum metal center. The mobility of the tetramethylaluminate ligands of complexes CpR′Ln(OArtBu,R)(AlMe4) (Ln = Y, Lu) was examined by variable-temperature (VT) 1H NMR spectroscopy, revealing two signals for bridging and terminal methyl groups at lower temperatures. The treatment of complexes CpR′Ln(OArtBu,R)(AlMe4) with donor solvent d8-THF gave CpR′Ln(OArtBu,R)(Me)(d8-THF)2 (Ln = Y, Lu) with terminal methyl groups, according to a donor-induced aluminate cleavage reaction. Dimeric [(C5Me5)Ln(OCH2CMe3)2]2 (Ln = Y, Lu) was synthesized from (C5Me5)Ln(NiPr2)2(THF) and reacted with two equivalents of TMA per Ln center to yield monomeric bis(TMA) adduct complexes (C5Me5)Ln(OCH2CMe3)2(AlMe3)2(Ln = Y, Lu). VT NMR spectroscopic studies confirmed a high mobility of the Ln(μ-OCH2CMe3)(μ-Me)AlMe2 moieties at an ambient temperature. Both bis(TMA) adduct complexes were characterized by X-ray structure analysis. 相似文献
55.
A goal of sensory coding is to capture features of sensory input that are behaviorally relevant. Therefore, a generic principle of sensory coding should take into account the motor capabilities of an agent. Up to now, unsupervised learning of sensory representations with respect to generic coding principles has been limited to passively received sensory input. Here we propose an algorithm that reorganizes an agent''s representation of sensory space by maximizing the predictability of sensory state transitions given a motor action. We applied the algorithm to the sensory spaces of a number of simple, simulated agents with different motor parameters, moving in two-dimensional mazes. We find that the optimization algorithm generates compact, isotropic representations of space, comparable to hippocampal place fields. As expected, the size and spatial distribution of these place fields-like representations adapt to the motor parameters of the agent as well as to its environment. The representations prove to be well suited as a basis for path planning and navigation. They not only possess a high degree of state-transition predictability, but also are temporally stable. We conclude that the coding principle of predictability is a promising candidate for understanding place field formation as the result of sensorimotor reorganization. 相似文献
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A comparison was made between a hay fed group, consisting of 23 ewes, and a grass silage fed group of 22 ewes, all pregnant. Excretion of Listeria monocytogenes (Lm) in the faeces and milk, antibody titres in sera and whey and delayed hypersensitivity against Lm, and several blood components were determined. The animals had previously been exposed to Lm, and Lm was isolated from the faeces from several animals when the experiment started. No significant difference in number of excretors between the 2 groups was found during the experimental period. The haemagglutination titres in both sera and whey were low and on the same level in both groups. The titres were higher in animals with 1 foetus than in animals with more than 1 foetus. In the first part of the experimental period the silage group had a reduced number of lymphocytes, lower total serum protein values and higher serum iron values, compared with the hay group. The silage group also had a stronger delayed hypersensitivity reaction against Lm than the hay group, and in the silage group the reaction was significantly stronger in ewes with 3 or more foetuses than in ewes with 1 foetus. In conclusion, the combined effect of some of the changes found in animals fed grass silage may leave them more susceptible to infections. 相似文献
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