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131.
Kovarova H Hajduch M Livingstone M Dzubak P Lefkovits I 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2003,787(1):53-61
In this paper we focus on the detection of specific state of protein phosphorylation within a complex protein mixture separated by two-dimensional gel electrophoresis followed by immunoblotting. The availability of antibodies that specifically recognize the phosphorylated residue(s) of proteins make this approach feasible as exemplified by the study of the regulatory mechanisms of the cell cycle. The major advantage of the presented approach is its relative simplicity and sensitivity that allows specific detection of protein phosphorylation and distinguishes different phosphorylation sites of target protein. Current findings demonstrate that this method represents a reasonable alternative to the use of other tools to study protein phosphorylation. 相似文献
132.
Klára Řeháková Eliška Zapomělová Ondřej Prášil Jana Veselá Hana Medová Aharon Oren 《Hydrobiologia》2009,636(1):77-88
There are several conflicting hypothesis that deal with the influence of flooding in the natural river–floodplain systems.
According to the Flood Pulse Concept, the flood pulses are not considered to be a disturbance, while some recent studies have
proven that floods can be a disturbance factor of phytoplankton development. In order to test whether flooding acts as a disturbance
factor in the shallow Danubian floodplain lake (Lake Sakadaš), phytoplankton dynamics was investigated during two different
hydrological years—extremely dry (2003) without flooding and usually flooded (2004). A total of 18 phytoplankton functional
groups were established. The sequence of phytoplankton seasonality can be summarized P/D → E (W1, W2) → C/P (only in potamophase) → S2/H1/SN/S1 → W1/W2 → P/D. The canonical correspondence analysis (CCA) demonstrated that the water level was a significant environmental
variable in 2004. Due to the higher total biomass of Bacillariophyceae established under potamophase conditions, floodings
in the early spring seem to be a stimulating factor for phytoplankton development. On the other hand, the flood pulses in
May and June had dilution effects on nutrients, so that a significantly lower phytoplankton biomass was established indicating
that flooding pulses can be regarded as a disturbance event. Such conditions supported diatom development (D, P, C species)
and prolonged its dominance in the total phytoplankton biomass. A long-lasting Cyanoprokaryota bloom (various filamentous
species—S1, S2, SN and H1 representatives) with very high biomass characterized the limnophase (dry conditions) in summer and autumn of both
years. In-lake variables (lake morphology, internal loadings of nutrients from sediments, light conditions) seem to be important
for the appearance of Cyanoprokaryota bloom. The equilibrium phase was found during the Cyanoprokaryota bloom only in the
extremely dry year. This study showed that depending on the time scale occurrence, flood pulses can be a stimulating or a
disturbance factor for phytoplankton development in Lake Sakadaš.
Handling editor: J. Padisak 相似文献
133.
Nur Syafiqah Abdul Ghani Roghayeh Abedi Karjiban Mahiran Basri Nur Hana Faujan Wui Zhuan Lim 《International journal of peptide research and therapeutics》2017,23(3):393-407
Alzheimer’s disease (AD) is a neurodegenerative disorder caused by overproduction and accumulation of amyloid beta-peptide (Aβ). The hallmarks associated with this AD are the presence of Aβ plaques between the nerve cell in the brain which leading to synaptic loss in memory. The amyloid plaques contain of transition metals like zinc, copper and iron. In a healthy brain, the metal ions are present in balance concentration. High concentrations of Zn are normally released during neurotransmission process. The release of Zn might cause the aggregation of Aβ leading to AD. Amyloid-β1–42 is the main type of Aβ in amyloid plaque. There still have limited explanation on how Aβ1–42 interaction with Zn metal, as well as the effect of Zn metal on the Aβ structure in different solvents in atomic detail. Therefore, we investigated the structural changes of Aβ1–42 in water (Aβ-H2O) and the mixed hexafluoroisopropanol (HFIP) with water (Aβ-HFIP/H2O). The mixed solvent consisted of hexafluoroisopropanol (HFIP) and water was used with the ratio of HFIP:H2O (80:20). The effect of zinc ion was also examined for the interaction of Aβ peptide with zinc in water (Aβ-Zn-H2O) and mixed solvent (Aβ-Zn-HFIP/H2O) using all atom level molecular dynamics (MD) calculations for 1 μs. We found that Aβ-Zn-HFIP/H2O contained more α-helix compared to Aβ-HFIP/H2O while Aβ-H2O and Aβ-Zn-H2O produced well-dissolved structure and they contained more β-sheets. β-turns are possible to bind with the receptor proteins and may induce the aggregation process in AD. Thus, Aβ-H2O and Aβ-Zn-H2O have higher possibility leading to AD compared to Aβ-Zn-HFIP/H2O and Aβ-HFIP/H2O models. 相似文献
134.
Luchman HA Friedman HC Villemaire ML Peterson AC Jirik FR 《Genesis (New York, N.Y. : 2000)》2008,46(4):229-234
Employing the Hprt locus as the site for targeted transgenesis we have developed mice expressing the tamoxifen-inducible Cre-ER(T2) fusion protein under the control of the ARR2-rat probasin promoter. This system enables external control over the timing of prostate epithelial cell-specific gene alterations. Using both the ROSA26-lacZ and ROSA26-EYFP reporter strains to monitor recombinase activity, Cre-ER(T2) was found to be specifically expressed in the prostatic epithelium and was strictly tamoxifen dependent. This strain thus allows precise control over the timing of gene alterations in the mouse prostate, enabling analyses of the phenotypic consequences of gene alterations in mice of any age. It also provides an ideal platform to study the impact of environmental, hormonal, and age-related factors on prostate tumorigenesis. This latter feature will be of particular value given the paucity of murine models that accurately mimic the late onset and prolonged natural history of human prostate cancer. 相似文献
135.
Abouzeid H Boisset G Favez T Youssef M Marzouk I Shakankiry N Bayoumi N Descombes P Agosti C Munier FL Schorderet DF 《American journal of human genetics》2011,(1):773-98
Waardenburg anophthalmia syndrome, also known as microphthalmia with limb anomalies, ophthalmoacromelic syndrome, and anophthalmia-syndactyly, is a rare autosomal-recessive developmental disorder that has been mapped to 10p11.23. Here we show that this disease is heterogeneous by reporting on a consanguineous family, not linked to the 10p11.23 locus, whose two affected children have a homozygous mutation in SMOC1. Knockdown experiments of the zebrafish smoc1 revealed that smoc1 is important in eye development and that it is expressed in many organs, including brain and somites. 相似文献
136.
Itoh S Saito T Hirata M Ushita M Ikeda T Woodgett JR Algül H Schmid RM Chung UI Kawaguchi H 《The Journal of biological chemistry》2012,287(35):29227-29236
137.
138.
3alpha,17beta-Dihydroxy-3beta-methyl-5alpha-androstan-6-one (1) and 3beta,17beta-dihydroxy-3alpha-methyl-5alpha-androstan-6-one (13) were prepared by the reaction of methylmagnesium bromide with the 3-ketosteroids. Structures and configurations in position 3 were determined by NMR spectra. Substitution in the position 6 influences the ratio of the products. 相似文献
139.
Dagmar Jičínská Eduard Brabec Marcel Rejmánek Jan Jeník Joří Haager Josef Holub Věroslav Samek Hana Rambousková Josef Holub Marie Naděžda Končalová Robert Neuhäusl Josev Kyncl František Krahuleo Jaroslav Dobrý Blanka Úlehlová Jiří Úlehla Eliška Rybníčková Kamil Rybníček 《Folia Geobotanica》1982,17(4):431-448
140.