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801.
HRT preserves increases in bone mineral density and reductions in body fat after a supervised exercise program 总被引:3,自引:0,他引:3
Kohrt Wendy M.; Ehsani Ali A.; Birge Stanley J. Jr. 《Journal of applied physiology》1998,84(5):1506-1512
The aims of thisstudy were to confirm our previous finding that hormone-replacementtherapy (HRT) augments exercise-induced increases in bone mineraldensity (BMD) in older women and to determine whether HRT preserves theadaptations when exercise is reduced or discontinued. The studyincluded an 11-mo treatment phase and a 6-mo follow-up phase.Participants, aged 66 ± 3 yr, were assigned to control (Con;n = 10), exercise (Ex;n = 18), HRT(n = 10), and Ex+HRT(n = 16) groups. HRT was continuedduring the follow-up. After the treatment phase, changes in total body BMD were 0.5 ± 1.7, 1.5 ± 1.4, 1.2 ± 0.8, and 2.7 ± 1.2% in Con, Ex, HRT, and Ex+HRT, respectively. Ex+HRT was moreeffective than HRT in increasing BMD of the total body and tended(P = 0.08) to be more effective at thelumbar spine. Ex+HRT was more effective than Ex in increasing BMD ofthe total body, lumbar spine, and trochanter. Exercise-induced gains inBMD were preserved during the follow-up only in those individuals onHRT. HRT also attenuated fat accumulation, particularly in theabdominal region, after the exercise program. These findings suggestthat HRT is an important adjunct to exercise for the prevention notonly of osteoporosis but also of diseases related to abdominal obesity. 相似文献
802.
Khalid Zemzoumi Denis Sereno Cline Francois Eliane Guilvard Jean-Loup Lemesre Ali Oualssi 《Biology of the cell / under the auspices of the European Cell Biology Organization》1998,90(3):239-245
In previous studies we have characterized several Leishmania major polypeptides and showed that one member of this group (LmSIR2rp) shared significant homology to silent information regulator 2 (SIR2) of Saccharomyces cerevisiae, a protein playing a role in both telomeric and mating type loci repression in these organisms. In the present study, by using molecular and immunological approaches, we could identify LmSIR2rp homologues in different Leishmania species and developmental stages (eg logarithmic (LP) and stationary phase promastigotes (SP) and amastigotes). The reactive antigen was also detected in Trypanosoma cruzi extracts. Surprisingly, immunofluorescence assays revealed that LmSIR2rp is associated mainly with cytoplasmic granules of different sizes and numbers depending on the life stage of the parasite used. No reactivity was observed in the nucleus, in agreement with the Western blot showing an absence of immunoreactivity of anti-LmSIR2rp immune serum against parasite nuclear extracts. Furthermore, immunoprecipitation of [35S]methionine-labeled promastigote antigens after pulse chase experiments, using anti-LmSIR2rp fusion protein antibodies, showed that the protein is among parasite excreted-secreted antigens (ESA). Moreover, immunoflurescence assays conducted with short time incubations of either purified LmSIR2rp or viable promastigotes with murine macrophages, revealed that LmSIR2rp could be bound to the macrophage surface. The unexpected cytoplasmic localization of LmSIR2rp and its presence in ESA may suggest a new mode of action for silent information regulatory factor homologues. 相似文献
803.
804.
Houyem Mansouri Ines Zemni Leila Achouri Najet Mahjoub Mohamed Ali Ayedi Ines Ben Safta Tarek Ben Dhiab Riadh Chargui Khaled Rahal 《Reports of Practical Oncology and Radiotherapy》2021,26(2):266
BackgroundThe management of gastric adenocarcinoma is essentially based on surgery followed by adjuvant treatment. Adjuvant chemotherapy (CT) as well as chemoradiotherapy (CTRT) have proven their effectiveness in survival outcomes compared to surgery alone. However, there is little data comparing the two adjuvant approaches. This study aimed to compare the prognosis and survival outcomes of patients with gastric adenocarcinoma operated and treated by adjuvant radio-chemotherapy or chemotherapyMaterials and methodsWe retrospectively evaluated 80 patients with locally advanced gastric cancer (LGC) who received adjuvant treatment. We compared survival outcomes and patterns of recurrence of 53 patients treated by CTRT and those of 27 patients treated by CT.ResultsAfter a median follow-up of 38.48 months, CTRT resulted in a significant improvement of the 5-year PFS (60.9% vs. 36%, p = 0.03) and the 5-year OS (55.9% vs. 33%, p = 0.015) compared to adjuvant CT. The 5-year OS was significantly increased by adjuvant CTRT (p = 0.046) in patients with lymph node metastasis, and particularly those with advanced pN stage (p = 0.0078) and high lymph node ratio (LNR) exceeding 25% (p = 0.012). Also, there was a significant improvement of the PFS of patients classified pN2–N3 (p = 0.022) with a high LNR (p = 0.018). CTRT was also associated with improved OS and PFS in patients with lymphovascular and perineural invasion (LVI and PNI) compared to chemotherapy.ConclusionThere is a particular survival benefit of adding radiotherapy to chemotherapy in patients with selected criteria such as lymph node involvement, high LNR LVI, and PNI. 相似文献
805.
A Ca2+‐binding protein with numerous roles and uses: parvalbumin in molecular biology and physiology
Syed Hasan Arif 《BioEssays : news and reviews in molecular, cellular and developmental biology》2009,31(4):410-421
Parvalbumins (PVs) are acidic, intracellular Ca2+‐binding proteins of low molecular weight. They are associated with several Ca2+‐mediated cellular activities and physiological processes. It has been suggested that PV might function as a “Ca2+ shuttle” transporting Ca2+ from troponin‐C (TnC) to the sarcoplasmic reticulum (SR) Ca2+ pump during muscle relaxation. Thus, PV may contribute to the performance of rapid, phasic movements by accelerating the contraction–relaxation cycle of fast‐twitch muscle fibers. Interestingly, PVs promote the generation of power stroke in fish by speeding up the rate of relaxation and thus provide impetus to attain maximal sustainable speeds. However, immunological monitoring of diverse tissues demonstrated that PVs are also present in non‐muscle cells. The axoplasmic transport and various intracellular secretory mechanisms including the endocrine secretions seem to be controlled by the Ca2+ regulation machinery. Any defect in the Ca2+ handling apparatus may cause several clinical problems; for instance, PV deficiency alters the neuronal activity, a key mechanism leading to epileptic seizures. Moreover, atypical relaxation of the heart results in diastolic dysfunction, which is a major cause of heart failure predominantly among the aged people. PV may offer a unique potential to correct defective relaxation in energetically compromised failing hearts through PV gene transfer. Consequently, PV gene transfer may present a new therapeutic approach to correct cellular disturbances in Ca2+ signaling pathways of diseased organs. Hence, PVs appear to be amazingly useful candidate proteins regulating a variety of cellular functions through action on Ca2+ flux management. 相似文献
806.
807.
A series of dioxouranium(VI) complexes was synthesised with some Schiff base ligands containing substituent groups at para positions to CHN groups. These molecules were obtained by the condensation of para-nitro, chloro, bromo, hydroxy, methyl and methoxy aniline with salicylaldehyde. The bidentate ligands formed complexes of the type UO2(NCS)2 (X-N-Sal)n·mH2O, where n = 2, m = 3, x = NO2, Cl, Br and OH; n = 3, m = 2, x = CH3 and OCH3.Conductivity measurements indicate that all the complexes are non-electrolytes in nitromethane solution, whereas in DMF they correspond to 1:1 electrolytes.IR spectral data suggest that the molecules and not the anions of the Schiff base are coordinated to the central uranium atom. IR and Raman spectra suggest that the complexes UO2(NCS)2(X-N-Sal)2· 3H2O (X = NO2, Cl, Br) have C2h molecular symmetry, whereas UO2(NCS)2(X-N-Sal)3·2H2O (X = OCH3, CH3) have C2v symmetry.The frequencies of UO2(asym) (IR) and UO2(sym) (R) in the complexes seem to vary with the various substituents of the Schiff base ligand, in the order:NO2 > Cl > Br > OH > CH3 > OCH3 相似文献
808.
Robert J Spina Timothy E Meyer Linda R Peterson Dennis T Villareal Morton R Rinder Ali A Ehsani 《Journal of applied physiology》2004,97(5):1654-1659
Recent evidence suggests that octogenarians exhibit attenuated adaptations to training with a small increase in peak O2 consumption (VO2) that is mediated by a modest improvement in cardiac output without an increase in arteriovenous O2 content difference. This study was designed to determine whether diminished increases in peak VO2 and cardiac output in the octogenarians are associated with absence of left ventricular and arterial adaptations to exercise training. We studied 22 octogenarians (81.9 +/- 3.7 yr, mean +/- SD) randomly assigned a group that exercised at an intensity of 82.5 +/- 5% of peak heart rate for 9 mo and 14 (age 83.1 +/- 4.1) assigned to a control group. Peak VO2 increased 12% in the exercise group but decreased slightly (-7%) in the controls. The exercise group demonstrated significant but small decreases in the heart rate (6%, P = 0.002) and the rate-pressure product (9%, P = 0.004) during submaximal exercise at an absolute work rate. Training induced no significant changes in the left ventricular size, geometry (wall thickness-to-radius ratio), mass, and function assessed with two-dimensional echocardiography or in arterial stiffness evaluated with applanation tonometry. Data suggest that the absence of cardiac and arterial adaptations may in part account for the limited gain in aerobic capacity in response to training in the octogenarians. 相似文献
809.
Thin‐Film Solar Cells with InP Absorber Layers Directly Grown on Nonepitaxial Metal Substrates
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Maxwell Zheng Hsin‐Ping Wang Carolin M. Sutter‐Fella Corsin Battaglia Shaul Aloni Xufeng Wang James Moore Jeffrey W. Beeman Mark Hettick Matin Amani Wei‐Tse Hsu Joel W. Ager Peter Bermel Mark Lundstrom Jr‐Hau He Ali Javey 《Liver Transplantation》2015,5(22)
The design and performance of solar cells based on InP grown by the nonepitaxial thin‐film vapor–liquid–solid (TF‐VLS) growth technique is investigated. The cell structure consists of a Mo back contact, p‐InP absorber layer, n‐TiO2 electron selective contact, and indium tin oxide transparent top electrode. An ex situ p‐doping process for TF‐VLS grown InP is introduced. Properties of the cells such as optoelectronic uniformity and electrical behavior of grain boundaries are examined. The power conversion efficiency of first generation cells reaches 12.1% under simulated 1 sun illumination with open‐circuit voltage (VOC) of 692 mV, short‐circuit current (JSC) of 26.9 mA cm?2, and fill factor (FF) of 65%. The FF of the cell is limited by the series resistances in the device, including the top contact, which can be mitigated in the future through device optimization. The highest measured VOC under 1 sun is 692 mV, which approaches the optically implied VOC of ≈795 mV extracted from the luminescence yield of p‐InP. 相似文献