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Sleep and Biological Rhythms - 相似文献
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Jan Willem Erisman Nelleke Domburg Wim de Vries Hans Kros Bronno de Haan Kaj Sanders 《中国科学:生命科学英文版》2005,48(Z2)
The Netherlands is "well known" for its nitrogen problems; it has one of the highest reactive nitrogen (Nr) emission densities in the world. It is a small country at the delta of several large European rivers. Ever since the industrial revolution, there has been a growing excess of nutrients and related emissions into the atmosphere (ammonia, nitrogen oxides and nitrous oxide) and into groundwater and surface water (nitrate), leading to a large range of cascading environmental impacts. Vehicular traffic, sewage and animal husbandry are the main sources of oxidized and reduced forms of Nr. This paper provides an overview of the origin and fate of nitrogen in the Netherlands, the various reported impacts of nitrogen, the Dutch and European policies to reduce nitrogen emissions and related impacts. In addition, ways are presented to go forward to potentially solve the problems in a European perspective. Solutions include the improvement of nitrogen efficiencies in different systems, technological options and education. 相似文献
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The intermediate filament (IF) synemin gene encodes three IF proteins (H 180, M 150, L 41 kDa) with overlapping distributions.
Synemin M was present early with vimentin and nestin. Synemin H was found later in the nervous system and mesodermic derivatives
concomitantly with angiogenesis and the migration of neural crest cells. Synemin L appeared later in neurons. A series of
in vitro cell cultures were done to identify the linkage between synemin isoforms and specific cell types of the central nervous
system (CNS). The neurons and glia from the brains of humans and rats were cultured and double immunostaining done with antibodies
against the H/M or L synemin isoforms and neural cell types (βIII-tubulin or NeuN) or astrocyte intermediate filaments (GFAP
or vimentin). In neurons of the CNS, synemin H/M were co-expressed with GFAP, vimentin or nestin in glial cells, whereas synemin
L was found in neurons. 相似文献
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Naumenko VS Tkachev SE Kulikov AV Semenova TP Amerhanov ZG Smirnova NP Popova NK 《Genes, Brain & Behavior》2008,7(3):300-305
Hibernation is a unique physiological state characterized by profound reversible sleep-like state, depression in body temperature and metabolism. The serotonin 5-hydroxytryptamine1A (5-HT1A ) receptor gene sequence in typical seasonal hibernator, ground squirrel ( Spermophilus undulatus ), was specified. It was found that the fragment encoding the fifth transmembrane domain showed 93.6% of homology with the analogous fragment of the mouse and rat genes and displayed 88.5% homology with the human 5-HT1A receptor gene. Using primers designed on the basis of obtained sequence, the expression of 5-HT1A receptor gene in the brain regions in active, entering into hibernation, hibernating and coming out of hibernation ground squirrels was investigated. Significant structure-specific changes were revealed in the 5-HT1A messenger RNA (mRNA) level in entry into hibernation and in arousal. An increase in the 5-HT1A gene expression was found in the hippocampus during the prehibernation period and in ground squirrels coming out of hibernation, thus confirming the idea of the hippocampus trigger role in the hibernation. Significant decrease in 5-HT1A receptor mRNA level in the midbrain was found in animals coming out of hibernation. There was no considerable changes in 5-HT1A receptor mRNA level in different stages of sleep–wake cycle in the frontal cortex. Despite drastically decreased body temperature in hibernating animals (about 37°C in active and 4–5°C in hibernation), 5-HT1A receptor mRNA level in all examined brain regions remained relatively high, suggesting the essential role of this 5-HT receptor subtype in the regulation of hibernation and associated hypothermia. 相似文献
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Mitochondrial DNA (mtDNA) restriction-site maps for six species (10
strains) of the Drosophila montium subgroup were established. A total of 50
restriction sites were mapped, corresponding to 1.67% of the mtDNA genome.
On the basis of differences in the restriction sites, nucleotide divergence
(delta) was calculated for each pair of species (strains), and phylogenetic
trees were constructed by using distance- matrix and parsimony methods.
Comparison of the resultant phylogenetic trees shows that the sibling
species D. auraria and D. quadraria are closely related. At the other
extreme, considerable divergence was observed between the two strains of D.
serrata and between D. serrata and D. birchii, a finding that contrasts
with their grouping within the same species complex. Nevertheless, our data
indicate that these six oriental montium species are rather closely
related.
相似文献
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Ensiling whole-crop wheat and corn in large containers with Lactobacillus plantarum and Lactobacillus buchneri 总被引:1,自引:0,他引:1
Weinberg ZG Ashbell G Hen Y Azrieli A Szakacs G Filya I 《Journal of industrial microbiology & biotechnology》2002,28(1):7-11
The effect of applying Lactobacillus buchneri, alone or in combination with Lactobacillus plantarum, at ensiling, on the aerobic stability of wheat and corn silages was studied in 50-l plastic containers. Treatments comprised
control (no additives), L. plantarum, L. buchneri and a combination of L. plantarum+L. buchneri. After 3 months of storage, the wheat silages treated with L. buchneri had higher acetic acid contents than the control or L. plantarum-treated silages, and were free of mold, whereas the top layers of the control or L. plantarum-treated silages were moldy. In an aerobic stability test the L. buchneri-treated silages were stable, whereas those treated with L. plantarum deteriorated. In the corn silages the effects of L. buchneri were not as clear and the top layer was moldy in all silages. However, L. buchneri also improved the aerobic stability of the corn silage, as indicated by lower yeast numbers, less CO2 production and stable pH. It is concluded that L. buchneri has a potential as a silage additive that protects the silage upon aerobic exposure. The 50-l plastic containers can serve
as an appropriate model to test silage additives before conducting full-scale farm experiments. Journal of Industrial Microbiology & Biotechnology (2002) 28, 7–11 DOI: 10.1038/sj/jim/7000207
Received 17 April 2001/ Accepted in revised form 25 August 2001 相似文献
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