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排序方式: 共有365条查询结果,搜索用时 15 毫秒
71.
El Abed K Rebai H Bloomer RJ Trabelsi K Masmoudi L Zbidi A Sahnoun Z Hakim A Tabka Z 《Journal of strength and conditioning research / National Strength & Conditioning Association》2011,25(9):2400-2409
It is well recognized that acute strenuous exercise is accompanied by an increase in free-radical production and subsequent oxidative stress, in addition to changes in blood antioxidant status. Chronic exercise provides protection against exercise-induced oxidative stress by upregulating endogenous antioxidant defense systems. Little is known regarding the protective effect afforded by judo exercise. Therefore, we determined antioxidant and oxidative stress biomarkers at rest and in response to acute exercise in 10 competitive judokas and 10 sedentary subjects after mixed exercise (anaerobic followed by aerobic). The subjects performed a Wingate test, followed by 30 minutes of aerobic exercise performed at 60% of maximal aerobic power. Blood samples were taken, by an intravenous catheter, at rest (R), immediately after the physical exercise (P0), and at 5 (P5), 10 (P10), and 20 (P20) minutes postexercise. The measured parameters included the activity of the antioxidant enzymes superoxide dismutase, glutathione peroxidase, and glutathione reductase, in addition to α-tocopherol, and total antioxidant status. Malondialdehyde was measured as a representation of lipid peroxidation. At rest, the judokas had higher values for all antioxidant and oxidative stress markers as compared to the sedentary subjects (p < 0.05). Plasma concentrations of all parameters except for α-tocopherol increased significantly above resting values for both the judokas and sedentary subjects (p < 0.05) and remained elevated at 20 minutes postexercise. A significant postexercise decrease was observed for α-tocopherol (p < 0.05) at P20 for judokas and at P5 for sedentary subjects. These data indicate that competitive judo athletes have higher endogenous antioxidant protection compared to sedentary subjects. However, both groups of subjects experience an increase in exercise-induced oxidative stress that is not different. 相似文献
72.
73.
Adnan A. Bekhit Hayam M. A. Ashour Hamdy M. Abdel-Rahman Salma A. Bekhit 《Journal of enzyme inhibition and medicinal chemistry》2013,28(1):296-309
Four series of pyrazolylbenzenesulfonamide derivatives were synthesized and evaluated for their anti-inflammatory activity using cotton pellet induced granuloma and carrageenan-induced rat paw edema bioassays. Moreover, COX-1 and COX-2 inhibitory activity, ulcerogenic effect and acute toxiCIT000y were also determined. Furthermore, the target compounds were screened for their in-vitro antimicrobial activity against Eischerichia coli, Staphylococcus aureus and Candida albicans. Compounds 4-(3-Phenyl-4-cyano-1H-pyrazol-1-yl)benzenesulfonamide 9a and 4-(3-Tolyl-4-cyano-1H-pyrazol-1-yl)benzenesulfonamide 9b were not only found to be the most active dual anti-inflammatory antimicrobial agents in the present study with good safety margin and minimal ulcerogenic effect but also exhibited good selective inhibitory activity towards COX-2. A docking pose for 9a and 9b separately in the active site of the human COX-2 enzyme was also obtained. Therefore, these compounds would represent a fruitful matrix for the development of dual anti-inflammatory antimicrobial candidates with remarkable COX-2 selectivity. 相似文献
74.
Optimization of pectin extraction from lemon by-product with acidified date juice using response surface methodology 总被引:4,自引:0,他引:4
Manel Masmoudi Souhail Besbes Moncef Chaabouni Christelle Robert Michel Paquot Christophe Blecker Hamadi Attia 《Carbohydrate polymers》2008,74(2):185-192
Response surface methodology was used to optimize pectin recovery from lemon by-product using an acidified date juice as extraction solution. When enriched in pectin, this latter can be useful for preparation of date-lemon jelly. The effects of three parameters namely temperature, pH and extraction time, on pectin extraction were studied. The fitted mathematical model allowed us to plot response surfaces as well as isoresponse curves and to determine optimal extraction conditions. Results clearly indicated that the temperature was the main factor influencing the pectin yield which increased with temperature and time or decreasing pH. The selected optimal conditions were: temperature 84.34 °C; extraction time 3 h 34 min and pH 2.8. These conditions yielded about 11.21% of pectin versus 10.89% for the predicted value. 相似文献
75.
L. Ammar-Keskes N. Chakroun-Fki F. Bouzid A. Bahloul S. Masmoudi M. Trifa T. Rebaï S. Rekik N. Mhiri 《Andrologie》1999,9(4):472-480
There are numerous controverses concerning the relationship between the presence of leukocytes in semen and male infertility. In the aim to determine the impact of pyospermia on sperm quality, we have realised a retrospective study in which we analysed and compared semen parameters and abnormalities frequencies between pyospermic and non pyospermic infertile patients. 833 spermiograms were included in this study. They were done in accord with WHO method. Leucocytes identification was performed by cyto-enzymologic method that reveals myelo-peroxydase in polymorphonuclear granulations. Pyospermia was considered when number of leucocytes was more than one million per millititre of sperm. The non pyospermic group was composed by sperm with leucocytospermia less than 50.000 per millilitre. The prevalence of pyospermia was 5.88%. There was not significative difference of semen parameters (volume, motility, morphology, number of spermatozoa and viability) between pyospermic and non pyospermic groups. In the other hand, no correlation was found between leucospermia and semen parameters. However, oligospermia was significantly more frequent in pyospermic group (40.8%) than in non pyospermic group (20,3%). Inversly, the frequence of teratospermia was significantly higher in non pyospermic group (47.2% vs 34.1%, p<0,05). These results suggest that inflammation and/or infection associated with pyospermia is complicated by reduction of spermatic ducts permeability. Although, the leucocytes would act in removing amorphous gametes by phagocytosis. No relationship was established between pyospermia and infection. In future, a prospective study would be done with exhaustive exploration of pyospermia etiology, with hopes to clarify the true link with infection and autoimmune reaction and to determine the effect of pyospermia on glandular activities in male genital tract and on functional properties of spermatozoa. 相似文献
76.
Amara I Odena A Oliveira E Moreno A Masmoudi K Pagès M Goday A 《Plant & cell physiology》2012,53(2):312-329
LEA (late embryogenesis abundant) proteins participate in plant stress tolerance responses, but the mechanisms by which protection occurs are not fully understood. In the present work the unfolded proteins from maize dry embryos were analyzed by mass spectrometry. Twenty embryo proteins were identified, and among them 13 corresponded to LEA-type proteins. We selected three major LEA proteins, Emb564, Rab17 and Mlg3, belonging to groups 1, 2 and 3, respectively, and we undertook a comparative study in order to highlight differences among them. The post-translational modifications of native proteins were analyzed and the anti-aggregation properties of recombinant Emb564, Rab17 and Mgl3 proteins were evaluated in vitro. In addition, the protective effects of the LEA proteins were assessed in living cells under stress in Escherichia coli cells and in Nicotiana bentamiana leaves agroinfiltrated with fluorescent LEA-green fluorescent protein (GFP) fusions. Protein visualization by confocal microscopy indicated that cells expressing Mg3-GFP showed reduced cell shrinkage effects during dehydration and that Rab17-GFP co-localized to leaf oil bodies after heat shock. Overall, the results highlight differences and suggest functional diversity among maize LEA groups. 相似文献
77.
Salma Taboubi Fran?oise Garrouste Fabrice Parat Gilbert Pommier Emilie Faure Sylvie Monferran Hervé Kovacic Maxime Lehmann 《Molecular biology of the cell》2010,21(6):946-955
Insulin-like growth factor-I (IGF-I) activation of phosphoinositol 3-kinase (PI3K) is an essential pathway for keratinocyte migration that is required for epidermis wound healing. We have previously reported that activation of Gα(q/11)-coupled-P2Y2 purinergic receptors by extracellular nucleotides delays keratinocyte wound closure. Here, we report that activation of P2Y2 receptors by extracellular UTP inhibits the IGF-I–induced p110α-PI3K activation. Using siRNA and pharmacological inhibitors, we demonstrate that the UTP antagonistic effects on PI3K pathway are mediated by Gα(q/11)—and not G(i/o)—independently of phospholipase Cβ. Purinergic signaling does not affect the formation of the IGF-I receptor/insulin receptor substrate-I/p85 complex, but blocks the activity of a membrane-targeted active p110α mutant, indicating that UTP acts downstream of PI3K membrane recruitment. UTP was also found to efficiently attenuate, within few minutes, the IGF-I–induced PI3K-controlled translocation of the actin-nucleating protein cortactin to the plasma membrane. This supports the UTP ability to alter later migratory events. Indeed, UTP inhibits keratinocyte spreading and migration promoted by either IGF-I or a membrane-targeted active p110α mutant, in a Gα(q/11)-dependent manner both. These findings provide new insight into the signaling cross-talk between receptor tyrosine kinase and Gα(q/11)-coupled receptors, which mediate opposite effects on p110α-PI3K activity and keratinocyte migration. 相似文献
78.
Khan WN Lodhi MA Ali I Azhar-Ul-Haq Malik A Bilal S Gul R Choudhary MI 《Journal of enzyme inhibition and medicinal chemistry》2006,21(1):17-19
Phytochemical investigations on the chloroform and ethyl acetate soluble fractions of the roots of Ranunculus repens led to the isolation of methyl 3,4,5-trihydroxybenzoate 1, R(+)- 4-methoxydalbergione 2 and R(+)-dalbergiophenol 3. The structures of these compounds were established through spectral studies including 1D and 2D NMR experiments and by comparison with literature data. These compounds showed potent inhibitory activity against urease. 相似文献
79.
Soudani A Hadjfredj S Zribi M Messaadi F Messaoud T Masmoudi A Zribi M Fendri C 《Journal of microbiology (Seoul, Korea)》2011,49(3):413-417
Forty three isoniazid (INH)-resistant Mycobacterium tuberculosis isolates were characterized on the basis of the most common INH associated mutations, katG315 and mabA −15C→T, and phenotypic properties (i.e. MIC of INH, resistance associated pattern, and catalase activity). Typing for resistance
mutations was performed by Multiplex Allele-Specific PCR and sequencing reaction. Mutations at either codon were detected
in 67.5% of isolates: katG315 in 37.2, mabA −15C→T in 27.9 and both of them in 2.4%, respectively. katG sequencing showed a G insertion at codon 325 detected in 2 strains and leading to amino acid change T326D which has not been
previously reported. Distribution of each mutation, among the investigated strains, showed that katG S315T was associated with multiple-drug profile, high-level INH resistance and loss or decreased catalase activity; whereas
the mabA −15C→T was more prevalent in mono-INH resistant isolates, but it was not only associated with a low-level INH resistance.
It seems that determination of catalase activity aids in the detection of isolates for which MICs are high and could, in conjunction
with molecular methods, provide rapid detection of most clinical INH-resistant strains. 相似文献
80.