341 research outputs found
Hemmende und förderliche Faktoren des Einsatzes digitaler Medien im Unterricht: empirische Befunde und forschungsmethodische Probleme
No full textIn den letzten Jahren hat eine Reihe von Studien gezeigt, dass in deutschen und schweizerischen Schulen Computer und Internet zwar zunehmend zur Verfügung stehen, diese jedoch nur verhältnismäßig selten im Unterricht eingesetzt warden (vgl. Korte/Hüsing 2006; Shewbridge/Ikeda/Schleicher 2006). Angesichts der Größenordnung der getätigten Investitionen in Infrastruktur und Weiterbildung und auch angesichts der hohen Priorität, die dem Thema ICT (d. h. Informationsund Kommunikationstechnologien) in politischen Strategiepapieren beigemessen wird (vgl. in der Schweiz z. B. EDK 2007; Schweizerischer Bundesrat 2006; international z. B. Rychen/Salganik 2003), muss sich pädagogische Forschung mit der Frage beschäftigen, warum die Schule nur schleppend in der Informationsgesellschaft ankommt. Im englischsprachigen Raum wurde das Phänomen von Cuban (2001) unter dem Schlagwort „Oversold & Underused“ prägnant auf den Punkt gebracht. Zur Erklärung dieser Situation werden in Studien vor allem zwei, teilweise auch miteinander kombinierte Ansätze verfolgt (vgl. im Überblick z. B. Somekh 2008; Balanskat/Blamire/Kefala 2006; Webb/Cox 2004; Mumtaz 2000). Einerseits geht es darum, die Aspekte zu erfassen, die einem verstärkten Einsatz im Wege stehen (sog. „barriers“, vgl. Jones 2004), andererseits wird versucht, Faktoren zu bestimmen, die mit einer verstärkten Nutzung korrespondieren (sog. „enablers“, vgl. Scrimshaw 2004). Beides geschieht sowohl anhand qualitativer Fallstudien und Beobachtungen (z. B. Eickelmann 2010; Schulz-Zander 2005; Kozma 2003; Venezky/Davis 2002) als auch durch Befragungen anhand größerer Stichproben (z. B. Law/Pelgrum/Plomp 2008; Pelgrum 2001). Gerade letzterer Ansatz hat neuerdings zu verblüffenden Resultaten mit hoher Erklärungskraft geführt. Im sogenannten Will/Skill/Tool-Modell werden drei Faktoren identifiziert, mit denen 90 % der Varianz des Grades der ICT-Integration im Unterricht erklärt werden können (vgl. Christensen/ Knezek, 2008; Morales Velázquez 2006). Ein ähnliches Modell wurde etwa zeitgleich von anderen Autoren und unter anderem Namen verfolgt (vgl. das Access/Competence/Motivation-Modell bei Korte/Hüsing 2006; Viherä/Nurmela 2001)
Sp1 inhibition downregulates ET<sub>B</sub>R expression and vascular contractility after MCAO.
No full text<p><b>A.</b> Representative ET<sub>B</sub>R and Sp1 immunostainings in the MCA on the occluded side (RMCA). Stainings show changes in the expression levels after treatment with MitA compared to vehicle (n = 4 per group). <b>B.</b> Graphs depict concentration-response curves of the MCA segments elicited by cumulative application of S6c (ET<sub>B</sub>R specific) of MitA and vehicle treated rats after MCAO. Vehicle vs. RMCA MitA, P<0.0001 and LMCA Vehicle vs. RMCA MitA, not significant. <b>C.</b> Graphs depict concentration-response curves of the MCA segments elicited by cumulative application of ET-1 of MitA and vehicle treated rats after MCAO. No significant difference between the groups (Vehicle, n = 4 and MitA, n = 6). <b>Statistics:</b> Values are presented as mean ± S.E.M. One-way ANOVA and Dunnet's multiple comparison test was performed to obtain statistical significance.</p
Increased vascular smooth muscle expression of Sp1 and ET<sub>B</sub>R after MCAO and organ culture.
No full text<p><b>A.</b> Representative immunohistochemical stainings of MCA sections from MCAO rats after 48 hrs. of I/R (LMCA: non-occluded side and RMCA: occluded side) (n = 4 per group). Scale bar is 50 µm. <b>B.</b> Bar graphs show the statistical significance of intensity measurements of Sp1 and ET<sub>B</sub>R in figure 1A (***P<0.001, *P<0.05). <b>C.</b> Representative western blot shows protein levels of ET<sub>B</sub>R and Sp1 in cultured cerebral arteries at 24 hrs. (n = 4 per group). <b>D.</b> Quantitative PCR analysis of ET<sub>B</sub>R and Sp1 mRNA levels in cultured cerebral arteries at 6 hrs. (n = 4 per group, **P<0.01). <b>E.</b> Immunohistochemical staining showing the expression and localization of Sp1 in fresh and 24 hrs. cultured MCAs (n = 4 per group). Scale bar is 50 µm. <b>Statistics</b>: Values are presented as mean ± S.E.M. Mann-Whitney test was performed between two groups for statistical significance.</p
Inhibition of Sp1 blocks ET<sub>B</sub>R mediated cerebrovascular contractility <i>ex vivo</i>.
No full text<p><b>A.</b> Graphs depict concentration-response curves of 24 hrs. organ cultured (cultured) and non-cultured (Fresh) MCA segments elicited by cumulative application of S6c (ET<sub>B</sub>R specific) in the presence or absence of MitA in a dose dependent manner (Fresh n = 6, OC n = 5, 2 µM MitA n = 3, 5 µM MitA n = 4). OC vs. 2 µM MitA; not significant. OC vs. 5 µM MitA; P = 0.0004. <b>B.</b> Graphs show concentration-response curves of cultured and fresh MCA segments elicited by cumulative application of ET-1 in the presence or absence of MitA (Fresh n = 5, OC n = 4, 5 µM MitA n = 5). No significant difference between the groups was observed. <b>Statistics:</b> Values are presented as mean ± S.E.M. One-way ANOVA and Dunnett's multiple comparison test was performed for statistical significance.</p
Inhibition of transcription factor Sp1 blocks ET<sub>B</sub>R upregulation <i>ex vivo</i> in rat and human cerebral arteries.
No full text<p><b>A.</b> Representative western blot for Sp1 and ET<sub>B</sub>R protein levels in cultured cerebral arteries with and without 5 µM MitA at 24 hrs. <b>B and C.</b> Bar graphs show the statistical significance of protein expression and inhibition of Sp1 and ET<sub>B</sub>R in figure 2A (Fresh n = 7, OC n = 7, MitA n = 6, **P<0.01, *P<0.05). <b>D and E.</b> Quantitative PCR analysis of ET<sub>B</sub>R and Sp1 mRNA levels in fresh and 24 hrs. cultured MCA segments with and without MitA treatment (n = 6 per group, **P<0.01, *P<0.05). <b>F.</b> Representative immunohistochemical stainings of MCAs cultured in the presence or absence of MitA at 24 hrs. (n = 4 per group). Scale bar is 50 µm. <b>G.</b> Immunohistochemical stainings of cultured human cerebral arteries show ET<sub>B</sub>R and Sp1 immunoreactivity with and without MitA treatment at 24 hrs. (n = 4 per group). Scale bar is 50 µm. <b>Statistics</b>: Values are presented as mean ± S.E.M. One-way ANOVA and Dunnett's multiple comparison test was done for figure B, C and D while Mann-Whitney test was done for figure E for statistical significance.</p
Consistency and inconsistency in testing biomarkers in breast cancer. A GRELL study in cut-off variability in the Romance language
No full textPURPOSE: Biological markers are crucial factors in order to differentiate female breast cancers and to determine the right therapy. This study aims at evaluating whether testing for biomarkers for female breast cancer has similar frequency and characteristics across and within countries.
METHODS: Population-based cancer registries of the Association for cancer registration and epidemiology in Romance language countries (GRELL) were asked to complete a questionnaire on biomarkers testing. The data collected referred to invasive female breast cancer cases diagnosed between 2004 and 2009. The investigation focused on 1) the overexpression and amplification of the human epidermal growth factor receptor 2 oncogene (HER2); 2) the expression of oestrogen (ER) and progesterone (PgR) receptors; and 3) the proliferation index (PI). Weighted percentages, the heterogeneity among and within countries, and the correlation between responses and calendar years were evaluated. The study was based on 19,644 breast cancers.
RESULTS: Overall, 85.9% of the cases were tested for HER2, 91.8% for both ER and PgR, and 74.1% for proliferative markers. For HER2 and ER-PgR, the frequency of testing increased from 2004 to 2009. Testing varied among countries (HER2 from 82.0% to 95.9%, ER-PgR from 89.3% to 98.9%, PI from 10% to 92%) and also within the same country (e.g. HER2 in Italy from 51% to 99%) as well as within single cancer registries. The most relevant differences were in the scores for positive/negative/not clearly defined HER2 (e.g. HER2 was defined positive if IHC 3+ in 21/33 registries), and in the cut-off of positive cells for ER/PgR (from >0% to >30%) and PI positivity (from >0% to >20%).
CONCLUSIONS: Biological markers are widely tested in the Romance language countries; however, the parameters defining their positivity may vary, raising concerns about homogeneity in breast cancer classification and treatment
The Berlin water company. From "inevitable" privatization to "impossible" remunicipalization
No full textFormosulfathiazole: A Structural Revision
No full textFormosulfathiazole (FSTz) is a synthetic active pharmaceutical ingredient (API) prepared by condensation of sulfathiazole with formaldehyde. Originally described for the first time in 1948, it is currently used for the treatment of bacterial and protozoal infections in cattle and pets, acting as a prodrug slowly releasing the sulfamidic sulfathiazole and formaldehyde. A systematic analysis of FSTz allowed to revise the originally believed undefined polymeric structure and uncovered the intriguing cyclophane skeleton of a well-defined cyclodimeric condensation product
ERK1/2 mediated phosphorylation of Sp1 is essential for ET<sub>B</sub>R upregulation.
No full text<p><b>A.</b> and <b>B.</b> Bar graphs show the time-dependent changes in the phosphorylation status of Sp1 (T453) and ERK1/2 based on the intensity measurements of western blots (n = 4 per group). No statistical difference between groups was observed. <b>C.</b> Representative western blot showing the time-dependent changes in the phosphorylation status of Sp1 (T453) and ERK1/2 in culture conditions. <b>D.</b> Representative immunohistochemical staining of MCA sections showing the phosphorylation status of Sp1 (T739) after 120 min of culturing (n = 4 per group). <b>Statistics</b>: Values are presented as mean ± S.E.M. One-way ANOVA and Bonferronis multiple comparison test was performed for statistical significance.</p
Regulatory mechanism of endothelin receptor B in the cerebral arteries after focal cerebral ischemia.
No full textIncreased expression of endothelin receptor type B (ETBR), a vasoactive receptor, has recently been implied in the reduced cerebral blood flow and exacerbated neuronal damage after ischemia-reperfusion (I/R). The study explores the regulatory mechanisms of ETBR to identify drug targets to restore normal cerebral artery contractile function as part of successful neuroprotective therapy
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