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101.
The causal relationships among ethylene emission, oxidative burst and tissue damage, and the temporal expression patterns of some ethylene biosynthetic and responsive genes, were examined in the Never ripe (Nr) tomato (Lycopersicon esculentum) mutant and its isogenic wild type (cv. Pearson), to investigate the role played by the ethylene receptor LE-ETR3 (NR) in mediating the plant response to ozone (O(3)). Tomato plants were used in a time-course experiment in which they were exposed to acute O(3) fumigation with 200 nl l(-1) O(3) for 4 h. The pattern of leaf lesions indicated similar sensitivities to O(3) for cv. Pearson and Nr. In both genotypes, O(3) activated a hydrogen peroxide (H(2)O(2))-dependent oxidative burst, which was also ethylene-driven in Nr leaves. Ozone induced some ethylene and jasmonate biosynthetic and inducible genes, although with different timings and to different extents in the two genotypes. The overall data indicate that Nr retains partial sensitivity to ethylene, suggesting only a marginal role of the NR receptor in mediating the complex response of tomato plants to O(3).  相似文献   
102.
This study assessed the anthropometric and physiological characteristics of elite Melanesian futsal players in order to determine the best performance predictors. Physiological parameters of performance were measured in 14 Melanesian (MEL-G, 24.4±4.4 yrs) and 8 Caucasian (NMEL-G, 22.9±4.9) elite futsal players, using tests of jump-and-reach (CMJ), agility (T-Test), repeated sprint ability (RSA), RSA with change-of-direction (RSA-COD), sprints with 5 m, 10 m, 15 m, and 30 m lap times, and aerobic fitness with the 30-15 intermittent fitness test (30-15 IFT). The anthropometric data revealed significantly lower height for MEL-G compared with NMEL-G: 1.73±0.05 and 1.80±0.08 m, respectively; P = 0.05. The CMJ was significantly higher for MEL-G than NMEL-G: 50.4±5.9 and 45.2±4.3 cm, respectively; P = 0.05. T-Test times were significantly lower for MEL-G than NMEL-G: 10.47±0.58 and 11.01±0.64 seconds, respectively; P = 0.05. MEL-G height was significantly related to CMJ (r = 0.706, P = 0.01), CMJpeakP (r = 0.709, P = 0.01) and T-Test (r = 0.589, P = 0.02). No significant between-group differences were observed for sprint tests or 30-15 IFT, including heart rate and estimated VO2max. Between groups, the percentage decrement (%Dec) in RSA-COD was significantly lower in MEL-G than NMEL-G (P = 0.05), although no significant difference was noted between RSA and RSA-COD. Within groups, no significant difference was observed between %Dec in RSA or RSA-COD; P = 0.697. This study presents specific anthropometric (significantly lower height) and physiological (significantly greater agility) reference values in Melanesians, which, taken together, might help coaches and physical fitness trainers to optimize elite futsal training and talent identification in Oceania.  相似文献   
103.
Despite its growing popularity, few studies have investigated specific physiological demands for elite female futsal. The aim of this study was to determine aerobic fitness in elite female futsal players using laboratory and field testing. Fourteen female futsal players from the Venezuelan National team (age =21.2±4.0 years; body mass =58.6±5.6 kg; height =161±5.0 cm) performed a progressive maximal treadmill test under laboratory conditions. Players also performed a progressive intermittent futsal-specific field test for endurance, the Futsal Intermittent Endurance Test (FIET), until volitional fatigue. Outcome variables were exercise heart rate (HR), VO2, post-exercise blood lactate concentrations ([La]b) and running speeds (km · h-1). During the treadmill test, VO2max, maximal aerobic speed (MAS), HR and peak [La]b were 45.3±5.6 ml · kg-1 · min-1, 12.5±1.77 km · h-1, 197±8 beats · min-1 and 11.3±1.4 mmol · l-1, respectively. The FIET total distance, peak running velocity, peak HR and [La]b were 1125.0±121.0 m, 15.2±0.5 km · h-1, 199±8 beats · min-1 and 12.5±2.2 mmol · l-1, respectively. The FIET distance and peak speed were strongly associated (r= 0.85-87, p < 0.0001) with VO2max and MAS, respectively. Peak HR and [La]b were not significantly different between tests. Elite female futsal players possess moderate aerobic fitness. Furthermore, the FIET can be considered as a valid field test to determine aerobic fitness in elite level female futsal players.  相似文献   
104.
105.
Reproductive behavior is sexually differentiated in quail: The male-typical copulatory behavior is never observed in females even after treatment with high doses of testosterone (T). This sex difference in behavioral responsiveness to T is organized during the embryonic period by the exposure of female embryo to estrogens. We showed recently that the sexually dimorphic medial preoptic nucleus (POM), a structure that plays a key role in the activation of male copulatory behavior, is innervated by a dense steroid-sensitive network of vasotocin-immunoreactive (VT-ir) fibers in male quail. This innervation is almost completely absent in the female POM and is not induced by a chronic treatment with T, suggesting that this neurochemical difference could be organizational in nature. This idea was tested by injecting fertilized quail eggs of both sexes on day 9 of incubation with either estradiol benzoate (EB) (25 μg, a treatment that suppresses the capacity to show copulatory behavior in adulthood) or the aromatase inhibitor R76713 (10 μg, a treatment that makes adult females behaviorally responsive to T), or with the solvents as a control (C). At 3 weeks posthatch, all subjects were gonadectomized and later implanted with Silastic capsules filled with T. Two weeks later, all birds were perfused and brain sections were processed for VT immunocytochemistry. Despite the similarity of the adult endocrine conditions of the subjects (all were gonadectomized and treated with T Silastic implants providing the same plasma level of steroid to all subjects), major qualitative differences were observed in the density of VT-ir structures in the POM of the different groups. Dense immunoreactive structures (fibers and a few cells) were observed in the POM of C males but not females; EB males had completely lost this immunoreactivity (and lost the capacity to display copulatory behavior); and, conversely, R76713 females displayed a male-typical VT-ir system in the nucleus (and also high levels of copulatory behavior). Similar changes in immunoreactivity were seen in the nucleus of the stria terminalis and in the lateral septum (VT-ir fibers only in this case) but not in the magnocellular vasotocinergic system. These neurochemical changes closely parallel the effects of the embryonic treatments on male copulatory behavior. The vasotocinergic system of the POM can therefore be considered an accurate marker of the sexual differentiation of brain circuits mediating this behavior. © 1998 John Wiley & Sons, Inc. J Neurobiol 37: 684–699, 1998  相似文献   
106.
Epitope mapping of MDR1-P-glycoprotein using specific monoclonal antibodies (mAbs) may help in delineating P-glycoprotein topology and hence in elucidating the relationship between its structural organization and drug-efflux pump function. In this work, by using synthetic peptide scanning and phage display technologies, the binding sites of the mAb MM12.10, a novel antibody to intact human multidrug resistant (MDR) cells, were studied. The results we obtained confirm that two regions localized on the predicted fourth and sixth loops are indeed external and that MDR1 peptides covering the inner domain of the current 12 transmembrane segment (TMs) model of P-glycoprotein could form part of the MM12.10 epitope.  相似文献   
107.
 Genetic variability among 49 accessions of Triticum urartu was estimated by RFLP and RAPD marker analyses, and the two data sets were compared. One T. timopheevii accession and two accessions of T. durum and T. aestivum, respectively, were included to identify T. urartu accessions closely related to these polyploid wheats. Twenty eight RFLP clones and 29 RAPD primers generated 451 and 155 polymorphic bands, respectively. The three accessions from Armenia clustered together and were well separated from all other accessions, which showed less pronounced geographical patterns. Genetic similarity and co-phenetic values calculated with RAPD markers were very similar to those calculated with RFLP markers for the intraspecific comparisons, but not for the interspecific comparisons. The identification of individual T. urartu accessions which are more related to polyploid wheats than others was not possible. Received: 14 May 1996 / Accepted: 13 September 1996  相似文献   
108.
Eggs of the hard clam, Mercenaria mercenaria (L.), and the bay scallop, Argopecten irradians (Lamarck), were graded to three size categories, split into replicates and these were replicate-sampled. A chi-square analysis compared the proportion of larvae (48-h survival) to the proportions of eggs in each initial replicate experiment. Statistically significant differences attributed to egg size were found for both species. Large eggs survived better than small eggs, while those of intermediate size showed no difference between expected and observed survival.  相似文献   
109.
Honeybee-collected pollen is gaining attention as functional food for human consumption, due to antiproliferative, antiallergic, antibiotic, antidiarrheic and antioxidant activities. Among the different bioactive compounds, flavonoids from bee-collected pollen are currently recognised as powerful antioxidant and antiradical molecules. Traditional conservation methods influence pollen organoleptic properties as well as the contents of nutrients and nutraceutical compounds. Here, freeze-drying (FD) was proposed as a novel conservation method, estimating its adequacy as drying process by the evaluation of changes in free and total amino acids and proline as well as in their ratios. Honeybee-collected chestnut pollen was taken into consideration and the level of rutin, as main flavonoid, was considered as marker compound highlighting the maintenance of pollen nutraceutical properties. Results showed that FD influenced rutin level, depending on the FD duration. However, the free proline to free amino acid ratio was always below 80%, and the free amino acid to total amino acid ratio remained unaltered indicating the adequacy of the FD treatment, which did not affect the nutritional value of chestnut pollen. Overall, this study shed light on the nutraceutical profile of honeybee-collected chestnut pollen, highlighting the promising potential of FD as a novel method to treat pollen for human consumption.  相似文献   
110.
Intracellular concentrations of cyclic adenosine 3':5'-monophosphate (cyclic AMP) and cyclic guanosine 3':5'-monophosphate were measured in rat embryo fibroblasts stimulated to divide by either the addition of 12-0-tetradecanoyl phorbol-13-acetate (TPA) or a serum-supplemented medium change. Cyclic nucleotide levels were altered within minutes and large oscillations occurred in a reciprocal fashion over the pre-replicative and the replicative phases. Patterns of oscillating levels depended on the growth state of the cultures. Intracellular content of cyclic nucleotide similarly changed in response to either mitogenic treatment with the exception of the early alterations in cyclic AMP. The medium-change stimulation resulted within minutes in a drop of the cyclic AMP levels at confluence and a rise in growing cells when TPA-induced stimulation proceeded without altering those levels. Treatment with 4-0-methyl-phorbol didecanoate, a TPA derivative that is inactive as a tumor promoter, did not affect the cyclic nucleotide levels.  相似文献   
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