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71.
Karl Henrik Larsson Helga Grosse-Brauckmann Jean Keller 《Nordic Journal of Botany》1998,18(2):239-242
The new species Hyphoderma tibia (Aphyllophorales, Basidiomycotina) is described and illustrated using drawings and scanning electron microscope. 相似文献
72.
Helga Müller Undine E.M. Achilles-Day John G. Day 《European journal of protistology》2010,46(2):133-142
The survival of ciliate resting cysts, in the presence and absence of soil, was studied under two environmental stresses: desiccation and freezing. Laboratory strains of the common species Colpoda inflata and the rare species Meseres corlissi were used in these experiments, which yielded the following results: 1) Freezing of cysts in soil with a residual moisture level exceeding ~30% was destructive for both species. 2) Survival of Meseres corlissi cysts depended largely on the presence of soil. 3) In the absence of soil, Colpoda inflata cysts had greater tolerance to desiccation and freezing than Meseres corlissi cysts. Possible consequences for the distribution of natural populations are discussed. 相似文献
73.
Helga Szelke Sarah Schübel Job Harenberg Roland Krämer 《Bioorganic & medicinal chemistry letters》2010,20(4):1445-1447
Fluorescent perylenediimide probes modified with 2, 4, 6, or 8 ammonium groups were synthesized and their binding to the antithrombotic drug heparin was studied by fluorescence spectroscopy in solution. The polyanionic polysaccharide strands of heparin bind more probe molecules per sugar unit when the charge of the latter is low, and stability of the probe-heparin complex increases with increasing probe charge. 相似文献
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Timing of reproduction in a Darwin''s finch: temporal opportunism under spatial constraints 总被引:1,自引:0,他引:1
We investigated whether predation by the minor grison ( Galictis cuja , a small mustelid) played a key role in limiting a wild cavy population ( Cavia magna ), ultimately leading to its local extinction. Radio-telemetry and capture-mark-recapture techniques were used to estimate grison predation rates (kill rates), time-specific probabilities of apparent mortality (population loss rate), overall mortality and grison predation for the cavy population. Additionally, we present data on alternative prey species, grison diet and reproduction to show potential proximate mechanisms of grison predation on wild cavies. The predictions specified were mostly confirmed: (1) grison predation was responsible for almost 80% of the cavies killed by known predators; (2) grison predation probabilities paralleled those of overall mortality of cavies over time; and (3) also those of the apparent mortality of the population. Thus, the population dynamics and the local extinction of the cavy population were not due to emigration processes. (4) Grison predation rates were not density-dependent, but showed pronounced peaks during the austral summer. The grison mainly preyed on small mammals: two water-rat species and the wild cavies. When the availability of alternative prey decreased in summer, the grison appeared to specialise on cavies. The onset of grison reproduction was somewhat delayed in relation to the onset of cavy reproduction. The lack of alternative prey coincided with high grison food demands due to reproduction, leading to a very high predation pressure ultimately resulting in the local extinction of the cavy population. We conclude that grison predation was indeed the main factor driving changes of the cavy population studied and speculate why caviomorph rodents might be especially susceptible to local extinction processes. 相似文献
77.
Dina F. Ahram Sinisa D. Grozdanic Helga Kecova Arjen Henkes Rob W. J. Collin Markus H. Kuehn 《PloS one》2015,10(5)
Several dog breeds are susceptible to developing primary angle closure glaucoma (PACG), which suggests a genetic basis for the disease. We have identified a four-generation Basset Hound pedigree with characteristic autosomal recessive PACG that closely recapitulates PACG in humans. Our aim is to utilize gene mapping and whole exome sequencing approaches to identify PACG-causing sequence variants in the Basset. Extensive clinical phenotyping of all pedigree members was conducted. SNP-chip genotyping was carried out in 9 affected and 15 unaffected pedigree members. Two-point and multipoint linkage analyses of genome-wide SNP data were performed using Superlink-Online SNP-1.1 and a locus was mapped to chromosome 19q with a maximum LOD score of 3.24. The locus contains 12 Ensemble predicted canine genes and is syntenic to a region on chromosome 2 in the human genome. Using exome-sequencing analysis, a possibly damaging, non-synonymous variant in the gene Nebulin (NEB) was found to segregate with PACG which alters a phylogenetically conserved Lysine residue. The association of this variants with PACG was confirmed in a secondary cohort of unrelated Basset Hounds (p = 3.4 × 10-4, OR = 15.3 for homozygosity). Nebulin, a protein that promotes the contractile function of sarcomeres, was found to be prominently expressed in the ciliary muscles of the anterior segment. Our findings may provide insight into the molecular mechanisms that underlie PACG. The phenotypic similarities of disease presentation in dogs and humans may enable the translation of findings made in this study to patients with PACG. 相似文献
78.
Kirsten Schulz Jana Frahm Susanne Kersten Ulrich Meyer Jürgen Rehage Marion Piechotta Maria Meyerholz Gerhard Breves Dania Reiche Helga Sauerwein Sven D?nicke 《PloS one》2015,10(8)
The inhibition of dipeptidyl peptidase-4 (DPP4) via specific inhibitors is known to result in improved glucose tolerance and insulin sensitivity and decreased accumulation of hepatic fat in type II diabetic human patients. The metabolic situation of dairy cows can easily be compared to the status of human diabetes and non-alcoholic fatty liver. For both, insulin sensitivity is reduced, while hepatic fat accumulation increases, characterized by high levels of non-esterified fatty acids (NEFA) and ketone bodies.Therefore, in the present study, a DPP4 inhibitor was employed (BI 14332) for the first time in cows. In a first investigation BI 14332 treatment (intravenous injection at dosages of up to 3 mg/kg body weight) was well tolerated in healthy lactating pluriparous cows (n = 6) with a significant inhibition of DPP4 in plasma and liver. Further testing included primi- and pluriparous lactating cows suffering from subclinical ketosis (β-hydroxybutyrate concentrations in serum > 1.2 mM; n = 12). The intension was to offer effects of DPP4 inhibition during comprehensive lipomobilisation and hepatosteatosis. The cows of subclinical ketosis were evenly allocated to either the treatment group (daily injections, 0.3 mg BI 14332/kg body weight, 7 days) or the control group. Under condition of subclinical ketosis, the impact of DPP4 inhibition via BI 14332 was less, as in particular β-hydroxybutyrate and the hepatic lipid content remained unaffected, but NEFA and triglyceride concentrations were decreased after treatment. Owing to lower NEFA, the revised quantitative insulin sensitivity check index (surrogate marker for insulin sensitivity) increased. Therefore, a positive influence on energy metabolism might be quite possible. Minor impacts on immune-modulating variables were limited to the lymphocyte CD4+/CD8+ ratio for which a trend to decreased values in treated versus control animals was noted. In sum, the DPP4 inhibition in cows did not affect glycaemic control like it is shown in humans, but was able to impact hyperlipemia, as NEFA and TG decreased. 相似文献
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