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101.
1. Life‐history traits of herbivores are shaped by the combination of various extrinsic and intrinsic variables. However, studies investigating the impact of both variables on insect behavioural phenotypes are rare, and research including the modulation of host plant quality by arbuscular mycorrhiza (AM) (extrinsic variable) and the herbivore developmental stage (intrinsic variable) on aphid behaviour is lacking. 2. To study the influences of extrinsic and intrinsic variables on aphid performance and behaviour, individuals of the generalist aphid pest Myzus persicae (Sulzer) were reared on Plantago lanceolata and Poa annua plants that were either non‐mycorrhized (NM) or mycorrhized (AM). Aphid performance was monitored over 2 weeks. Behavioural traits of nymphs were recorded twice during development after removing individuals from their feeding sites and placing them in an unknown environment (‘open field’), causing disturbance. Plant quality was determined by measuring the water content and leaf mass per area (LMA). 3. Differences in body mass of nymphs at day 6 dependent on plant species and treatment were compensated by the individuals within 4 days. Behavioural traits, considered as activity and exploration, were affected by the interaction between extrinsic and intrinsic variables (activity and exploration) and changed over ontogeny (activity). Independent of AM, a lower water content and LMA were recorded in P. annua leaves. 4. Overall, this study demonstrates that extrinsic and intrinsic variables need to be considered in combination and behavioural traits should be studied repeatedly during insect ontogeny to understand the complexity of microbe‐modulated plant–herbivore interactions.  相似文献   
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ABSTRACT. Forty-eight stocks in Paramecium jenningsi, syngens 1–5 of P. multimicronucleatum, P. caudatum, P. primaurelia, P. biaurelia, and P. tetraurelia were grown axenically and tested for their esterases and acid phosphatases using starch gel electrophoresis. The five esterases and the acid phosphatases previously characterized in species of the P. aurelia complex were also found in P. jenningsi, and three to four of the esterases and the acid phosphatases were found in the P. multimicronucleatum species complex and in P. caudatum. Additional subtypes were observed for each of the enzyme phenotypes in these new (though here unnamed) species of Paramecium. Two of the new acid phosphatase subtypes, which depart radically in mobility and in pattern, were found in syngen 3 of P. multimicronucleatum and in P. caudatum. Except for syngens 1 and 5 in P. multimicronucleatum, the degree of similarity between syngens 1, 5 and 2, 3, and 4 appears to be very low—perhaps even lower than that seen for species in the aurelia complex. More realistically, the syngens of P. multimicronucleatum should be considered as separate species although they are not here given separate taxonomic names. Limited sharing of subtypes occurred between species in different species complexes. This observation suggests that the molecular distances between species complexes may be even greater than between species within a complex.  相似文献   
105.
Cuttings were either decapitated or both decapitated and disbudded at different time intervals. Auxin, at different concentrations, was applied to the cuttings in lanoline. Auxin applied to decapitated and disbudded cuttings promoted root formation in the early stage of the initiation phase. Auxin treated cuttings, which were only decapitated, did not show an increase in number of roots per cutting. However, an increase in the root mass was found in the early stage of the initiation phase. The results seem to indicate that auxin is active only in the first part of the initiation phase. It is acting alone, not together with other substances synthesized in the shoot meristem.  相似文献   
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Application of the herbicide 4-chloro-2-methylphenoxyaceticacid (MCPA), cadmium or nickel to the roots of rice, Oryza sativa(cv. Bahia) grown in solution culture resulted in changes tothe lipid composition and increases in the Mg2+-ATPase activityof the shoot plasma membranes. These increases in Mg2+-ATPaseactivity were associated with reductions in the campesterol:sitosterol ratio. There was no significant effect on membranefluidity (measured by steady-state fluorescence polarization)as a result of the treatments. The results suggested that therewas no consistent relationship between fluidity and Mg2+-ATPaseactivity. A possible involvement of sterols in the regulationof plasma membrane-bound ATPase activity is proposed. Key words: MCPA, heavy-metals, sterols, ATPase activity, plasma membranes  相似文献   
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The plumage coloration in great tits (Parus major) is the subject of much behavioural and ecophysiological research, yet there is a lack of analyses of the natural colour variation and its mechanisms. We used reflectance spectrometry and high‐performance liquid chromatography to explore individual, sexual and age‐related variation in carotenoid coloration and pigmentation, paramount to the often presumed, but rarely substantiated, costs and ‘honesty’ of carotenoid displays. In adults, we found that sex was the strongest predictor of ‘brightness’ (higher in males) and of ‘hue’ (longer wavelength in females). There was no sex difference in ‘carotenoid chroma’ or carotenoid content of feathers which also was unrelated to adult age (1 or 2+ years) and condition. Similar patterns were revealed for nestlings. Regarding the biochemical ‘signal content’, ‘carotenoid chroma’, but not ‘hue’, was significantly related to the carotenoid content (lutein and zeaxanthin) of feathers. These results refute the previously assumed exaggeration of carotenoid pigmentation in male great tits, and question the condition‐dependence of carotenoid coloration in this species. However, the sexual dimorphism in total reflectance or ‘brightness’, most likely due to melanins rather than carotenoids, may have implications for signalling or other adaptive explanations that need to be explored. © 2008 The Linnean Society of London, Biological Journal of the Linnean Society, 2008, 95 , 758–765.  相似文献   
110.

Background

Chronic venous leg ulcers (VLUs) are a common problem in clinical practice and available treatments are not satisfactory. The use of adjuvant therapies in combination with lower limb compression may lead to improved healing rates. Chronic wounds are candidates for new strategies in the emergent field of regenerative medicine. Bone marrow–derived cells (BMDCs) contain cells and secrete cytokines known to participate in wound healing. Thus, BMDC therapy seems a logical strategy for the treatment of chronic wounds. Our objective was to evaluate feasibility, safety and initial clinical outcome of autologous BMDC therapy associated with standard treatment in patients with VLUs.

Methods

We conducted an open-label, single-arm, prospective pilot clinical trial in four patients with six chronic VLUs. The study protocol was approved by the institutional and national review boards and ethics committees. Bone marrow was harvest, processed and then administered by multiple injections into the ulcers. All patients received standard treatment and non-healing characteristics of the VLUs were confirmed at study entry.

Results

Ulcer size and wound pain evaluated 12 months after BMDC treatment were significantly reduced (P < 0.05). BMDC treatment was safe and well tolerated in long-term follow-up.

Discussion

Despite the low number of patients studied, our results showed that autologous BMDC treatment could be a useful, feasible and safe procedure to enhance ulcer healing. However, randomized controlled trials with more patients are needed to address this question and translate this approach into clinical practice.  相似文献   
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