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941.
942.
Novel biomarkers for cancer diagnosis and therapy selection are urgently needed to facilitate early detection and improve therapy outcomes. We have previously identified a novel phosphorylation site at serine 506 (PS506) on topoisomerase-I (topo-I) and have shown that it is widely expressed in cell lines derived from several cancers, including lung cancer, but is low in cell lines derived from non-cancerous tissues. Here we have investigated how PS506 expression in lung tissue specimens correlates with their malignant status. We find that PS506 expression is significantly elevated in malignant tumors of non-small cell lung cancer (NSCLC) compared to adjacent, non-cancerous lung tissue and benign lung tumors. PS506 expression was up to 6-fold higher in malignant specimens than in paired non-malignant tissue. Using the well-characterized NIH/NCI 60-cell line panel, we correlate the most elevated expression levels of PS506 in lung, ovarian, and colon cancer cells lines with increased sensitivity to camptothecin, a plant alkaloid that targets topo-I. This is consistent with our earlier studies in a smaller sampling of cell lines and with our finding that PS506 increases topo-I DNA binding. Two widely used chemotherapeutic drugs for ovarian and colon cancer, topotecan and irinotecan, respectively, are derived from camptothecin. Irinotecan has also displayed efficacy in clinical trials of NSCLC. Our results suggest that elevated PS506 expression may correlate with clinical chemosensitivity to these agents in ovarian, colon, and NSCLC. PS506 may therefore serve as a biomarker for diagnosis or therapy selection. 相似文献
943.
Ludy Keino Frederick Baijukya Wilson Ng’etich Abigael N. Otinga John R. Okalebo Ruth Njoroge John Mukalama 《PloS one》2015,10(12)
Low soybean yields in western Kenya have been attributed to low soil fertility despite much work done on nitrogen (N) and phosphorus (P) nutrition leading to suspicion of other nutrient limitations. To investigate this, a nutrient omission trial was set up in the greenhouse at the University of Eldoret-Kenya to diagnose the nutrients limiting soybean production in Acrisols from Masaba central and Butere sub-Counties, and Ferralsols from Kakamega (Shikhulu and Khwisero sub-locations) and Butula sub-Counties and to assess the effect of liming on soil pH and soybean growth. The experiment was laid out in a completely randomized design with ten treatments viz; positive control (complete), negative control (distilled water), complete with lime, complete with N, minus macronutrients P, potassium (K), calcium (Ca), magnesium (Mg) and sulphur (S) and with, micro-nutrients boron (B), molybdenum (Mo), manganese (Mn), copper (Cu) and zinc (Zn) omitted. Visual deficiency symptoms observed included interveinal leaf yellowing in Mg omission and N addition and dark green leaves in P omission. Nutrients omission resulted in their significantly low concentration in plant tissues than the complete treatment. Significantly (P≤ 0.05) lower shoot dry weights (SDWs) than the complete treatment were obtained in different treatments; omission of K and Mg in Masaba and Shikhulu, Mg in Khwisero, K in Butere and, P, Mg and K in Butula. Nitrogen significantly improved SDWs in soils from Kakamega and Butula. Liming significantly raised soil pH by 9, 13 and 11% from 4.65, 4.91 and 4.99 in soils from Masaba, Butere and Butula respectively and soybean SDWs in soils from Butere. The results show that, poor soybean growth was due to K, Mg and P limitation and low pH in some soils. The results also signify necessity of application of small quantities of N for initial soybean use. 相似文献
944.
945.
946.
947.
Seetharamaiyer Padmanabhan Ruth C. Lavin Paresh M. Thakker Jinqing Guo Lu Zhang Deke Moore Michael E. Perlman Cassandra Kirk Deborah Daly Kathy J. Burke-Howie Teresa Wolcott Suchitra Chari David Berlove James B. Fischer William F. Holt Graham J. Durant Robert N. McBurney 《Bioorganic & medicinal chemistry letters》2001,11(24):1945-3155
Solution-phase synthesis of various acylguanidine derivatives and the evaluation of a small library of compounds as potential sodium channel blockers are described. 相似文献
948.
Eleni Karali Beat Brunner Ruth Doherty Anna M. Hersperger Mark D. A. Rounsevell 《Human ecology: an interdisciplinary journal》2013,41(6):915-926
Identifying and interpreting the heterogeneity of farmer behaviour is becoming increasingly important in support of policy- and decision-making goals. This paper explores whether observed differences in farming practices can be interpreted from the heterogeneity of farmer behaviour. Farmer attitudes and objectives were analysed using a combination of principal components and cluster analysis applied to responses to statements in a telephone-based survey. Respondents were classified into four profiles; business-oriented, lifestylers, multifunctionalists and traditionalists. Each profile differed in terms of farm management practices, the amount of land farmers either managed or owned, the existence of successors and the importance placed on household members in providing information. The results suggest that knowledge of farmer behavioural profiles could support more targeted policy development that accounts for alternative farmer goals. However, similarities were also found between the profiles, suggesting that farmer behaviour would be better interpreted as a dynamic set of identities, rather than as static profiles. 相似文献
949.
950.
Ruth Becker 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1932,16(2):515-528
Zusammenfassung Es wurde die Vaguswirkung bei den Herzen von drei Schlangenarten, Spilotes pullatus L., Coluber longissimus
Laur. und Coluber quatuorlineatus
Lac. geprüft. Durch einen Schwellenreiz wird das Herz nach einer Latenz von 1–2 Sek. stillgestellt. Nur in den seltensten Fällen gelang es, den Reiz so abzustufen, daß das Herz verlangsamt und mit verminderter Kraft weiter arbeitete.Bei schwachem Vagusreiz sind während des Stillstandes die Herzabteilungen noch erregbar. Auch wird die Erregung der einen Abteilung auf die benachbarten übertragen. Bei starkem Vagusreiz ziehen sich die Vorhöfe bei künstlicher Reizung mit außerordentlich herabgesetzter Kraft zusammen.Nach Beendigung des Vagusreizes nimmt das Herz seine Tätigkeit sofort in vollem Umfange wieder auf, wenn der Vagus schwach gereizt wurde. Wurde er stark gereizt, so macht sich eine stark negativ inotrope Wirkung an den verschiedenen Herzabteilungen mit Ausnahme der Kammer, bemerkbar. Eine Tonussenkung der verschiedenen Herzabschnitte durch eine Vagusreizung wurde niemals beobachtet. 相似文献