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441.
Immunoprecipitation of insulin receptors from cultured human lymphocytes (IM-9 cells) by antibodies to pp60src 总被引:2,自引:0,他引:2
N Perrotti S I Taylor N D Richert U R Rapp I H Pastan J Roth 《Science (New York, N.Y.)》1985,227(4688):761-763
The family of tyrosine-specific protein kinases includes proteins encoded by retroviral oncogenes as well as receptors for insulin and several growth factors. Antibodies to pp60src, the protein encoded by the src oncogene of Rous sarcoma virus (RSV), can specifically immunoprecipitate affinity-labeled insulin receptors from cultured human lymphocytes (IM-9 cells). This precipitation is specifically inhibited by the src gene product purified from RSV-transformed rat cells. These observations provide evidence that there is structural homology between the insulin receptors and pp60src. 相似文献
442.
Fritz J Roth M Holbach P Esselen M Marko D 《Journal of agricultural and food chemistry》2008,56(19):8891-8896
Delphinidin has been found to possess DNA strand-breaking properties in cell culture. In the present study, we demonstrated that the extent of DNA damage by delphinidin is not affected by the expression of tyrosyl-DNA-phosphodiesterase 1, indicating that the induction of DNA strand breaks is not predominantly topoisomerase-mediated. However, the DNA-damaging properties of delphinidin were decreased by the addition of catalase to the cell culture medium, counteracting delphinidin-mediated hydrogen peroxide formation. Under these conditions, delphinidin showed clearly antioxidative properties in HT29 cells, preventing menadione-induced oxidative DNA damage. In contrast, in the absence of catalase, delphinidin lacked antioxidative properties. In conclusion, delphinidin acted as an effective antioxidant within intact cells if the formation of hydrogen peroxide was prevented. In the absence of catalase, the accumulated hydrogen peroxide appears to play a substantial role for the observed DNA-damaging properties of delphinidin and the apparent lack of antioxidative properties of this anthocyanidin. 相似文献
443.
Perrin G Woillez J Lai O Guérin J Kotani T Wizinowich PL Le Mignant D Hrynevych M Gathright J Léna P Chaffee F Vergnole S Delage L Reynaud F Adamson AJ Berthod C Brient B Collin C Crétenet J Dauny F Deléglise C Fédou P Goeltzenlichter T Guyon O Hulin R Marlot C Marteaud M Melse BT Nishikawa J Reess JM Ridgway ST Rigaut F Roth K Tokunaga AT Ziegler D 《Science (New York, N.Y.)》2006,311(5758):194
Here we report successful interferometric coupling of two large telescopes with single-mode fibers. Interference fringes were obtained in the 2- to 2.3-micrometer wavelength range on the star 107 Herculis by using the two Keck 10-meter telescopes, each feeding their common interferometric focus with 300 meters of single-mode fibers. This experiment demonstrates the potential of fibers for future kilometric arrays of telescopes and is the first step toward the 'OHANA (Optical Hawaiian Array for Nanoradian Astronomy) interferometer at the Mauna Kea observatory in Hawaii. It opens the way to sensitive optical imagers with resolutions below 1 milli-arc second. Our experimental setup can be directly extended to large telescopes separated by many hundreds of meters. 相似文献
444.
445.
Lorenz RD Wall S Radebaugh J Boubin G Reffet E Janssen M Stofan E Lopes R Kirk R Elachi C Lunine J Mitchell K Paganelli F Soderblom L Wood C Wye L Zebker H Anderson Y Ostro S Allison M Boehmer R Callahan P Encrenaz P Ori GG Francescetti G Gim Y Hamilton G Hensley S Johnson W Kelleher K Muhleman D Picardi G Posa F Roth L Seu R Shaffer S Stiles B Vetrella S Flamini E West R 《Science (New York, N.Y.)》2006,312(5774):724-727
The most recent Cassini RADAR images of Titan show widespread regions (up to 1500 kilometers by 200 kilometers) of near-parallel radar-dark linear features that appear to be seas of longitudinal dunes similar to those seen in the Namib desert on Earth. The Ku-band (2.17-centimeter wavelength) images show approximately 100-meter ridges consistent with duneforms and reveal flow interactions with underlying hills. The distribution and orientation of the dunes support a model of fluctuating surface winds of approximately 0.5 meter per second resulting from the combination of an eastward flow with a variable tidal wind. The existence of dunes also requires geological processes that create sand-sized (100- to 300-micrometer) particulates and a lack of persistent equatorial surface liquids to act as sand traps. 相似文献
446.
Effect of days postburning and calcium oxide on the fermentation,aerobic stability and nutritional characteristics of sugarcane silage for finishing Nellore steers 下载免费PDF全文
Anna Paula T. P. Roth Gustavo R. Siqueira Carlos H. S. Rabelo Matheus H. Moretti Carla J. Härter Flávio D. Resende Ricardo A. Reis 《Grass and Forage Science》2018,73(3):671-684
In this study, the effects of days postburning and calcium oxide (CaO) on the fermentation, aerobic stability and nutritional characteristics of sugarcane silages for finishing Nellore steers were investigated. Silages were prepared in minisilos from in natura and burned sugarcane that remained in the field 1 and 10 days postburning (1‐day burned and 10‐day burned, respectively). Next, forages were left untreated or treated with CaO (10 g/kg fresh forage). Compared to that in untreated silages, CaO application increased the dry‐matter (DM) recovery of in natura, 1‐day and 10‐day burned silages (p < 0.001) by 67, 179 and 209 g/kg DM respectively. The CaO treatment increased (p < 0.001) the aerobic stability of the in natura and 10‐day burned silages by 62.7 and 24.7 hr respectively. In a feedlot experiment, feeding 1‐day burned silage reduced DM intake of steers throughout the feedlot period (0–93 days; p < 0.05) compared with that of steers fed in natura silage diet, but the average daily gain (ADG) was lower (p = 0.006) only during the adaptation period (?0.16 kg/day; 0–28 days). The CaO application decreased DM intake (p = 0.007; ?1.17 kg/day) and ADG (p < 0.001; ?0.13 kg/day) of steers only during the adaptation period likely owing to low silage palatability caused by increased Ca and butyric acid concentrations (≥11.6 g/kg DM). We recommend feeding beef cattle with CaO‐treated burned sugarcane silages in low‐dietary concentration because of its high butyric acid concentration. 相似文献
447.
The in vitro effect of bovine recombinant tumor necrosis factor-alpha (rbTNF-alpha) on bovine neutrophil function and the possibility that rbTNF-alpha and recombinant bovine interferon-gamma (rbIFN-gamma) act synergistically were investigated. Treatment of neutrophils with rbTNF-alpha (0.05 micrograms/ml; approximately 50 U/ml) at 37 degrees C for 2.5 h resulted in enhancement of antibody independent neutrophil-mediated cytotoxicity (AINC) and inhibition of random migration and chemotaxis. The same treatment resulted in a slight decrease in iodination and cytochrome C reduction, but did not affect Staphylococcus aureus ingestion, or antibody dependent cell-mediated cytotoxicity. Kinetic and inhibitor studies indicated that the action of rbTNF-alpha was rapid and was independent of protein and RNA synthesis by neutrophils. Evaluation of the synergistic activities of rbTNF-alpha and rbIFN-gamma indicated that treatment of neutrophils with these two cytokines simultaneously resulted in additive enhancement of AINC and inhibition of random migration and chemotaxis. There was no additive effect of the two cytokines on inhibition of iodination or cytochrome C reduction. 相似文献
448.
Relationships between flour functional properties and protein composition were studied using a set of 138 Argentinean wheat samples. Among different protein groups, the incremental increase of gliadin with increasing grain protein content was highest followed by polymeric protein with albumin‐globulin content much lower. Functional properties could be divided into two groups based on dependence on protein composition. Properties such as dough extensibility and bake test loaf volume correlated highly with the percentage of polymeric protein in the grain. Properties such as mixograph dough development time were best correlated with the percentage of polymeric protein in the protein (PPP). Alveograph tenacity showed no significant dependence on PPP. as found previously for extensigraph maximum resistance, but it was correlated with the percentage of unextractable polymeric protein in the protein. Energy (W) appeared to be a more useful alveograph parameter for predicting flour quality. 相似文献