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31.
We have screened seven Chrysanthemum species, collected from different biotope in Tunisia for the antifeeding and growth regulatory activity against S. littoralis (Lepidoptera: Noctuidae) an insect pest of tomato. The flowers powder was added to the Poitout and Bues (1974) artificial diet at three concentrations: 4, 8, and 16%. After ten days of treatment, the consumed quantity determination revelled that these species have an antifeeding activity proportional to the concentration, more considerable for the C. fuscatum and C. Myconis flowers powder. At the concentration of 16% the larvae weight was significantly delayed in the average time to the control, these results were compared to the effect of Cestrum parquii on S. littoralis and Pieris brassicae The moulting date determination showed an elongation of the third, fourth and fifth stages at the high concentration probably due to the presence of juvenile hormones Analogues.  相似文献   
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Covalent conjugation of poly(ethylene glycol) or "PEGylation" has proven an effective strategy to improve pharmaceutical protein efficacy by hindering recognition by proteases, inhibitors, and antibodies and by retarding renal clearance. Because it determines the strength and range of intermolecular steric forces and the hydrodynamic properties of the conjugates, the configuration of protein-conjugated PEG chains is the key factor determining how PEGylation alters protein in vivo circulation time. Mono-PEGylated proteins are typically described as having a protective PEG shroud wrapped around the protein, but recent dynamic light scattering studies suggested that conjugates adopt a dumbbell configuration, with a relatively unperturbed PEG random coil adjacent to the globular protein. We used small-angle neutron scattering (SANS) to distinguish between the dumbbell model and the shroud model for chicken-egg lysozyme and human growth hormone covalently conjugated to a single 20 kDa PEG chain. The SANS contrast variation technique was used to isolate the PEG portion of the conjugate. Scattering intensity profiles were well described by the dumbbell model and inconsistent with the shroud model.  相似文献   
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Objective

To examine the time-of-day and Ramadan fasting (RF) effects on serum apolipoprotein-AI (Apo-AI) and B (Apo-B), lipoprotein particles-a (Lp-a), high-sensitive C-reactive-protein (hs-CRP), and homocysteine (Hcy) during the Yo-Yo intermittent recovery test (YYIRT).

Design

Performance and biochemical measures were completed at two times-of-day (07:00 and 17:00 h), 1-week before RF (BR), the second week of RF (SWR), and the fourth week of RF (ER).

Setting

For each session, subjects performed the YYIRT, and blood samples were taken before and 3-min after the test for biochemical measures.

Participants

Fifteen soccer players.

Main Outcome Measures

Total distance during the YYIRT, core temperature, body composition, dietary intakes, lipid (HDL-C, LDL-C, Apo-AI, B and Lp-a) and inflammatory (hs-CRP and Hcy) profiles.

Results

Performances during the YYIRT were higher in the evening than the morning BR (P < 0.05), but this fluctuation was not observed during RF. Moreover, LDL-C, ApoB, and Lp-a were stable throughout the daytime BR. However, during RF, they decreased at 17:00 h (P < 0.05). Likewise, HDL-C and Apo-AI increased after the exercise and were higher at 17:00 h BR (P < 0.001). Moreover, these parameters increased during RF (P < 0.01). Furthermore, Hcy and hs-CRP increased during the exercise (P < 0.01) with higher evening levels BR. During ER, the diurnal pattern of Hcy was inversed (P < 0.001).

Conclusions

This study concluded that caloric restriction induced by RF seems to ameliorate lipid and inflammatory markers of cardiovascular health during intermittent exercise performed in the evening.  相似文献   
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To compare the effects of two nap opportunities (20 and 90 min) to countermeasure the transient naturally occurring increased sleepiness and decreased performances during the post-lunch dip (PLD). Fourteen highly trained judokas completed in a counterbalanced and randomized order three test sessions (control (No-nap), 20- (N20) and 90-min (N90) nap opportunities). Test sessions consisted of the running-based anaerobic sprint test (RAST), simple and multiple-choice reaction times (MCRT) and the Epworth sleepiness scale (ESS). From the RAST, the maximum (Pmax), mean (Pmean) and minimum (Pmin) powers were calculated. Blood samples were taken before and after the RAST to measure the effect of pre-exercise napping on energetic and muscle damage biomarkers and antioxidant defense. N20 increased Pmax and Pmean compared to No-nap (p < 0.001, d = 0.59; d = 0.66) and N90 (p < 0.001, d = 0.98; d = 0.72), respectively. Besides, plasma lactate and creatinine increased only when the exercise was performed after N20. Both N20 (p < 0.001, d = 1.18) and N90 (p < 0.01, d = 0.78) enhanced post-exercise superoxide dismutase activity compared to No-nap. However, only N20 enhanced post-exercise glutathione peroxidase activity (p < 0.001, d = 1.01) compared to pre-nap. Further, MCRT performance was higher after N20 compared to No-nap and N90 (p < 0.001, d = 1.15; d = 0.81, respectively). Subjective sleepiness was lower after N20 compared to No-nap (p < 0.05, d = 0.92) and N90 (p < 0.01, d = 0.89). The opportunity to nap for 20 min in the PLD enhanced RAST, MCRT performances, and antioxidant defense, and decreased sleepiness. However, the opportunity of 90 min nap was associated with decreased repeated sprint performances and increased sleepiness, probably because of the sleep inertia.  相似文献   
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Superoxide dismutase purified from the photoautotrophic cyanobacteriumGlœocapsa sp. has a molar mass of 38 kDa, as estimated by gel filtration. Inhibition pattern indicated limited resistance to H2O2 under conditions which entirely inhibited FeSOD. The enzyme is insensitive to cyanide and is inhibited by azide. This suggested the presence of a hybrid of two isozymes, FeSOD and a minor constituent of MnSOD. Amino acid composition of the purified SOD showed structural homology to FeSOD and MnSOD apoenzymes.  相似文献   
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We have determined the nucleotide sequence of a 1,200-base pair (bp) genomic fragment that includes the kappa-chain constant-region gene (C kappa) from two species of native Australian rodents, Rattus leucopus cooktownensis and Rattus colletti. Comparison of these sequences with each other and with other rodent C kappa genes shows three surprising features. First, the coding regions are diverging at a rate severalfold higher than that of the nearby noncoding regions. Second, replacement changes within the coding region are accumulating at a rate at least as great as that of silent changes. Third, most of the amino acid replacements are localized in one region of the C kappa domain--namely, the carboxy-terminal "bends" in the alpha-carbon backbone. These three features have previously been described from comparisons of the two allelic forms of C kappa genes in R. norvegicus. These data imply the existence of considerable evolutionary constraints on the noncoding regions (based on as yet undetermined functions) or powerful positive selection to diversify a portion of the constant-region domain (whose physiological significance is not known). These surprising features of C kappa evolution appear to be characteristic only of closely related C kappa genes, since comparison of rodent with human sequences shows the expected greater conservation of coding regions, as well as a predominance of silent nucleotide substitutions within the coding regions.   相似文献   
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