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41.
Prenatal growth is very complex and a highly integrated process. Both maternal nutrition and the maternal somatotropic axis play a significant role in coordinating nutrient partitioning and utilization between maternal, placental and fetal tissues. Maternal nutrition may alter the nutrient concentrations and in turn the expression of growth regulating factors such as IGFs and IGFBPs in the blood and tissues, while GH acts in parallel via changing IGFs/IGFBPs and nutrient availability. The similarity in the target components implies that maternal nutrition and the somatotropic axis are closely related to each other and may induce similar effects on placental and fetal growth. Severe restriction of nutrients throughout gestation has a permanent negative effect on fetal and postnatal growth, whereas the effects of both temporary restriction and feeding above requirements during gestation seem to be of transitional character. Advantages in fetal growth gained by maternal growth hormone treatment during early to mid-gestation are not maintained to term, whereas treatment during late or greatest part of gestation increases progeny size at birth, which could be of advantage for postnatal growth. This review summarizes the available knowledge on the effects of different maternal feeding strategies and maternal GH administration during pregnancy and their interactions on metabolic and hormonal (especially IGFs/IGFBPs) status in the feto-maternal unit, skeletal muscle development and growth of the offspring in pigs.  相似文献   
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Nematotoxic effect of an aqueous extract of Artemisia annua and its components caffeic acid, chlorogenic acid (5-caffeoylquinic acid, 5-CQA), artemisinin and the related semi-synthetic artesunate, was investigated on the root-knot nematode Meloidogyne incognita and the potato cyst nematode Globodera rostochiensis and on the virus-vector dagger nematode Xiphinema index. Juveniles of M. incognita and G. rostochiensis and females of X. index were exposed to 500, 250 and 125 μl ml?1 solutions of the A. annua aqueous extract, caffeic acid, chlorogenic acid and artesunate and to 50 μl ml?1 solution of artemisinin for 2, 4, 8 and 24 h. Egg masses of M. incognita and cysts of G. rostochiensis were exposed for 24, 48, 96 h and 1 or 2 weeks only to the extract solutions. Aqueous extract was highly effective on G. rostochiensis juveniles, whereas M. incognita juveniles were affected only at long exposure times. Adversely, egg hatch inhibition was strong on M. incognita and poor or minimal on G. rostochiensis. Females of X. index were sensitive only to long exposures to the highest extract concentration. Both caffeic and chlorogenic acid did not affect juveniles of M. incognita but were highly active on G. rostochiensis juveniles and X. index females even at the lowest concentration. Artesunate toxicity was almost zero on M. incognita and low on X. index females, but high on G. rostochiensis juveniles. Artemisinin solution was lethal to more than 50 % of G. rostochiensis juveniles within 24 h, but did not affect M. incognita juveniles and X. index females. Results suggest different roles of the tested compounds in the biocidal activity on each target nematode species. The extract of A. annua and its main phytochemicals seem to have a potential to be developed into new nematicidal formulates, though their activity should be validated in the soil.  相似文献   
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Secondary plants may be added to a cropping system for the purpose of improving pest control. In a recent article (Parolin P, Bresch C, Brun R, Bout A, Boll R, Desneux N, Poncet C (2012) Secondary plants used in biological control: a review, International Journal of Pest Management 58, 91–100) we defined different categories of secondary plants used to enhance biological control: companion, repellent, barrier, indicator, trap, insectary, and banker plants are intentionally added to agricultural systems in order to improve pest management through either top-down or bottom-up processes. In the present paper, we focus on the functional characteristics of secondary plants and on the mechanisms which contribute to reducing the presence of pests. If we understand and integrate the effects that such plants have on pests and beneficial arthropods, together with the multitrophic interactions in which these organisms are involved, the application of pesticides in crop systems can be reduced and enhanced productivity in agro-ecosystems achieved. Here, we identify the main characteristics of, and the prerequisites for, plants which can enhance crop protection in agro-ecosystems.  相似文献   
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Plant Foods for Human Nutrition - Glycine max (soybean) is a fundamental food in human nutrition, largely utilized by the consumers, and in particular, fermented soy is mainly used. However, health...  相似文献   
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Plants of the urban environment are exposed to a wide range of pollutants, including heavy metals. This research studies in situ the eco-physiological and antioxidant responses of holm oak (Q. ilex) leaves to Pb and Cd to assess the mechanisms of metal tolerance in this species, widely used as biomonitor. Leaves of plants grown at parks and roadsides were analyzed for photosynthetic activity, Pb and Cd concentration in tissues and cell-free extracts, thiol groups, D1 and Rubisco protein content, ascorbic acid (AsA) amount, and catalase (CAT) activity. The main results evidenced that Cd concentration was higher in leaves collected at the park out from the downtown; whereas Pb was most abundant in leaves sampled at the roadside nearby the highway. Pb in cell-free extracts was higher in park than in roadside leaves. Although Cd in the leaf tissues was twofold lower than Pb, it was more abundant than Pb in cellular extracts deprived of all particulate matter. Leaves responded to different concentration of Cd and Pb modulating some eco-physiological and biochemical traits, roadside leaves showed reduced leaf lamina, higher content of photosynthetic pigments, hydrogen peroxide, and AsA, as well as higher CAT activity compared to park leaves. In the roadside leaves, a stress condition for photosynthetic apparatus can be hypothesized on the basis of the decline of photochemical activity, the increase of NPQ, and the reduction of Rubisco and D1 protein content. The elevated presence of thiol groups in these leaves suggests a possible role of Pb and Cd in activation of antioxidant responses.  相似文献   
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We have searched for special characteristics in growth, protein expression, fatty acids and volatile organic compounds (VOCs) in a local Phaeodactylum tricornutum Bohlin strain (Bergen Marine Biobank), by comparing it with a common accession strain (CCAP). Differences in growth and expressed proteins were detected between the BMB strain and the CCAP strain, and the BMB strain reached the highest cell densities under the given growth conditions. Fatty acid (FA) analyses showed highest relative eicosapentaenoic acid (EPA) levels in the exponential phase (25.73% and 28.31%), and highest levels of palmitoleic acid (16:1 n-7) in the stationary phase (46.36% and 43.66%) in the BMB and CCAP strain, respectively. The most striking finding of the VOCs analyses was the relatively high levels of ectocarpene, 6-((1E)-butenyl)-1,4-cycloheptadiene, hormosirene, and desmarestene and structurally related compounds, which were exclusively detected in the BMB strain. Many of the VOCs detected in the CCAP and, in particular, in the BMB strain have been reported as antimicrobial agents. We suggest that the array of pheromones and antimicrobial substances could be part of an allelopathic strategy of the BMB strain, dominated by oval cells, thus reflecting the benthic life stage of this morphological form. These findings show the potential for bioactive metabolites in the BMB strain.  相似文献   
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