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排序方式: 共有2245条查询结果,搜索用时 46 毫秒
991.
Gianfranco De Feo Simona Signoriello Jane C. Bryce Antonia Del Giudice Giuliana Canzanella Federika Crudele Fiorella Romano Giovanni de Matteis Manuela Florio Fabiano Falasconi Alfonso Savio Pasqualina Giordano Gennaro Daniele Mario Iaccarino Maria Carmela Piccirillo Massimo Di Maio Alessandro Morabito Ciro Gallo Francesco Perrone 《PloS one》2010,5(7)
992.
Oscar González-Flores Carlos Beyer Marcos García-Juárez Alfonso Soto-Sánchez 《Hormones and behavior》2010,58(2):223-229
This study tested the hypothesis that the Src/Raf/MAPK signaling pathway is involved in the facilitation of the lordosis and proceptive behaviors induced by progesterone (P) and its ring A-reduced metabolites in ovariectomized, estradiol-primed rats. Intraventricular (icv) infusion of PP2 (7.5, 15 and 30 µg), a Src kinase inhibitor, significantly depressed P-dependent estrous behavior (lordosis and proceptivity) in estradiol-primed rats. Icv infusion of 30 µg of PP2 also significantly attenuated estrous behavior induced by the ring A-reduced P metabolites 5α-dihydroprogesterone (5α-DHP) and 5α-pregnan-3α-ol-20-one (allopregnanolone). PP2 did not inhibit estrous behavior induced by administration of high doses of estradiol alone to ovariectomized rats. We also assessed if the ventromedial hypothalamus (VMH) is one of the neural sites at which progestins activate Src signaling to facilitate estrous behavior. Bilateral administration of 15 µg of PP2 into the VMH inhibited the stimulation of both lordosis and proceptive behaviors elicited by subcutaneous P administration to estradiol-primed rats. These results suggest that progestins act through Src/Raf/MAPK signaling to initiate estrous behaviors in estrogen-primed rats. This event is one component of the cellular pathways leading to the display of estrous behaviors induced by P and its ring A-reduced metabolites in female rats. 相似文献
993.
Valeria Marina Nurchi Guido Crisponi Joanna Izabela Lachowicz Sergio Murgia Tiziana Pivetta Maurizio Remelli Antonio Rescigno Juan Niclós-Gutíerrez Josefa María González-Pérez Alicia Domínguez-Martín Alfonso Castiñeiras Zbigniew Szewczuk 《Journal of inorganic biochemistry》2010,104(5):560-569
With the aim to design new chelators for the clinical treatment of different diseases involving the trivalent metal ions Fe(III) and Al(III), we present the equilibria of kojic acid and its derivative 6-[5-hydroxy-2-hydroxymethyl-pyran-4-one]-5-hydroxy-2-hydroxymethyl-pyran-4-one with these two metal ions. Potentiometric and spectrophotometric techniques for iron, and potentiometry and 1H NMR for aluminum were used, supported by X-ray, electrospray ionization-mass spectrometry (ESI-MS), calorimetry and quantum chemical calculations. In this work, evidence is given on the formation of MeL, MeL2, and MeL3 complexes of both metal ions with kojic acid, confirmed by the X-ray structure of the FeL3 complex, and of variously protonated Me2L2 and MeL2 complexes of 6-[5-hydroxy-2-hydroxymethyl-pyran-4-one]-5-hydroxy-2-hydroxymethyl-pyran-4-one. The extremely good pFe value for this second ligand gives confidence to, and opens perspectives for, the search of new kojic acid derivatives. 相似文献
994.
Evaluation of single chemical extractants for the prediction of heavy metal uptake by barley in soils amended with polluted sewage sludge 总被引:1,自引:0,他引:1
José Martín Soriano-Disla Ignacio Gómez José Navarro-Pedreño Alfonso Lag-Brotons 《Plant and Soil》2010,327(1-2):303-314
The main aim of this study was to compare the suitability of three single chemical extractants [EDTA, CaCl2 and the low-molecular-weight organic acids solution (LMWOAs)] to estimate Cu, Zn and Ni uptake by barley (Hordeum vulgare) from rhizosphere soils, following a single application of a metal salts-spiked sewage sludge. Thirty-six contrasting soils from different parts of Spain were amended with the same dose (15.71 g dry weight kg-1) of polluted sewage sludge and sown with barley seeds under greenhouse conditions. Eight weeks after sowing, the plants were harvested and Cu, Zn and Ni were analysed in the roots. Heavy metal uptake was then compared with the theoretically available heavy metals in the rhizosphere soils, assessed by the three single chemical extractants. These three extractants alone failed to predict heavy metal uptake, and soil properties were needed to obtain accurate predictions. Thus, none of the methods tested in this study can be used as a universal soil extraction for estimating Cu, Zn and Ni uptake by barley. 相似文献
995.
Background
Cellular processes and pathways, whose deregulation may contribute to the development of cancers, are often represented as cascades of proteins transmitting a signal from the cell surface to the nucleus. However, recent functional genomic experiments have identified thousands of interactions for the signalling canonical proteins, challenging the traditional view of pathways as independent functional entities. Combining information from pathway databases and interaction networks obtained from functional genomic experiments is therefore a promising strategy to obtain more robust pathway and process representations, facilitating the study of cancer-related pathways. 相似文献996.
Benigno Linares Juan M Guizar Norma Amador Alfonso Garcia Victor Miranda Jose R Perez Rocío Chapela 《BMC pulmonary medicine》2010,10(1):1-9
Background
Poor adherence with prescribed asthma medication is a major barrier to positive treatment outcomes. This study was designed to determine the effect of a once-daily administration of mometasone furoate administered via a dry powder inhaler (MF-DPI) on treatment adherence compared with a twice-daily administration.Methods
This was a 12-week open-label study designed to mimic an actual clinical setting in patients ≥12 years old with mild-to-moderate persistent asthma. Patients were randomized to receive MF-DPI 400 μg once-daily in the evening or MF-DPI 200 μg twice-daily. Adherence was assessed primarily using the number of actual administered doses reported from the device counter divided by the number of scheduled doses. Self-reports were also used to determine adherence. Health-related quality of life, healthcare resource utilization, and days missed from work or school were also reported.Results
1233 patients were randomized. The mean adherence rates, as measured by the automatic dose counter, were significantly better (P < 0.001) with MF-DPI 400 μg once-daily in the evening (93.3%) than with MF-DPI 200 μg twice-daily (89.5%). Mean adherence rates based on self-reports were also significantly better (P < 0.001) with MF-DPI 400 μg QD PM (97.2%) than with MF-DPI 200 μg twice-daily (95.3%). Adherence rates were lower in adolescents (12-17 years old). Health-related quality of life improved by 20% in patients using MF-DPI once-daily in the evening and by 14% in patients using MF-DPI twice-daily. Very few (<8%) patients missed work/school.Conclusion
Mean adherence rates were greater with a once-daily dosing regimen of MF-DPI than with a twice-daily dosing regimen. This trial was completed prior to the ISMJE requirements for trial registration. 相似文献997.
Hernández-Godínez B Ibáñez-Contreras A Perdigón-Castañeda G Galván-Montaño A García-Montes de Oca G Zapata-Valdez C Tena-Betancourt E 《Comparative medicine》2010,60(5):396-399
Degenerative spinal disease is a leading cause of chronic disability both in humans and animals. Although widely seen as a normal occurrence of aging, degenerative spinal disease can be caused by various genetic, iatrogenic, inflammatory, and congenital factors. The objective of this study was to characterize the degenerative spine-related diseases and the age at onset in a random subpopulation of 20 captive rhesus monkeys (Macaca mulatta; male, 13; female, 7; age: range, 4 to 27 y; median, 18.5 y). Spinal radiographic evaluation (left lateral, right lateral, and ventrodorsal views) of the spinal column (C1 to S1) was performed, and spinal degenerative disease was scored. The incidence of osteopathology was higher in the 14- to 18-y-old group, but incidence did not differ according to sex. In the studied population, degenerative changes were present in monkeys as young as 9 y of age. 相似文献
998.
Ann C. Zovein Alfonso Luque Kirsten A. Turlo Jennifer J. Hofmann Kathleen M. Yee Michael S. Becker Reinhard Fassler Ira Mellman Timothy F. Lane M. Luisa Iruela-Arispe 《Developmental cell》2010,18(1):39-51
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999.
Oxidative stress plays an important role in arterial hypertension and propionyl-L-carnitine (PLC) has been found to protect cells from toxic reactive oxygen species. In this work, we have evaluated the antioxidant capacity of chronic PLC treatment in spontaneously hypertensive rats (SHR) by measuring the activity of antioxidant enzymes and the lipid peroxidation in liver and cardiac tissues. The activity of glutathione peroxidase was decreased in liver and cardiac tissues of SHR when compared with their normotensive controls, Wistar- Kyoto (WKY) rats, this alteration being prevented by PLC treatment. Glutathione reductase activity was increased in hypertensive rats and no effect was observed after the treatment. No significant changes in superoxide dismutase activity were observed among all experimental groups. Liver of hypertensive rats showed higher catalase activity than that of normotensive rats, and PLC enhanced this activity in both rat strains. Thiobarbituric acid reactive substances, determined as a measure of lipid peroxidation, were increased in SHR compared with WKY rats, and PLC treatment decreased these values not only in hypertensive rats but also in normotensive ones. The content of carnitine in serum, liver and heart was higher in PLC-treated rats, but PLC did not prevent the hypertension development in young SHR. In addition, triglyceride levels, which were lower in SHR than WKY rats, were reduced by chronic PLC treatment in both rat strains. These results demonstrate: i) the hypotriglyceridemic effect of PLC and ii) the antioxidant capacity of PLC in SHR and its beneficial use protecting tissues from hypertension-accompanying oxidative damage. 相似文献
1000.
The 52-aminoacid peptide adrenomedullin (AM) is expressed in the normal and malignant prostate. We have previously shown that prostate cancer cells produce and secrete AM, which acts as an autocrine growth inhibitory factor. We have evaluated in the present study the role of AM in prostate cancer cell apoptosis, induced either by serum deprivation or treatment with the chemotherapeutic agent etoposide (which acts as an inhibitor of topoisomerase II). For this purpose we over-expressed AM in PC-3, DU 145 and LNCaP cells, which were transfected with an expression vector carrying AM. We also treated the parental cell lines with synthetic AM in normal culture conditions and in conditions of induced-apoptosis. After serum removal, AM prevented apoptosis in DU 145 and PC-3 cells, but not in LNCaP cells. When treated with etoposide, AM prevented apoptosis in PC-3 and LNCaP cells, but not in DU 145 cells. Cell cycle analysis demonstrated a significant decrease in the percentage of AM-overexpressing PC-3 cells in the subG0/G1 phase after treatment with etoposide, as compared to the percentage of mock-transfected PC-3 treated cells. Western blot showed that protein levels of phosphorylated ERK1/2 increased in parental PC-3 cells after treatment with etoposide. In PC-3 cells overexpressing AM, phosphorylated ERK1/2 basal levels were lower than basal levels of parental PC-3 cells, and treatment with etoposide did not result in such an increase. Etoposide produced a significant increase in cleaved PARP in parental PC-3 cells. However, PC-3 clones overexpressing AM that were treated with etoposide only showed a mild increase in fragmented PARP. The ratio Bcl-2/Bax was reduced in parental or mock-transfected PC-3 cells after treatment with etoposide. On the contrary, this ratio was not reduced in PC-3 clones with AM overexpression that were treated with etoposide. All these data demonstrate that AM plays a protective role against induced apoptosis in prostate cancer cells. These results may have important implications in prostate cancer resistance to chemotherapeutic agents. 相似文献