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681.
Chronic and acute ethanol treatments increased the 3-hydroxybutyrate uptake by lactating rat mammary gland as a consequence of its high afferent concentration, without changing its relative extraction. The uptake of glucose was inhibited in the ethanol treated animals due to intrinsic alterations in the mammary gland metabolism as indicated by the decreased relative extraction and unchanged afferent concentration. These results would suggest that the elevated uptake of ketone bodies in ethanol-treated rats can be responsible, at least in part, for the decrease in glucose uptake by lactating rat mammary gland, although other direct effects of ethanol may be implied. 相似文献
682.
Vi L. Nguyen Justin L. Bastow Bruce A. Jaffee Don R. Strong 《Mycological Research》2007,111(7):856-862
To understand why Arthrobotrys oligospora and other nematode-trapping fungi are common and sometimes abundant in the coastal grassland soils of the Bodega Marine Reserve (BMR, Sonoma County, CA), we examined how resident trapping fungi responded to the addition of eight organic substrates (lupine leaves, grass leaves, dead isopods, dead moth larvae, isopod faeces, deer faeces, shrimp shells, and powdered chitin). We were especially interested in the effects of dead isopods because isopods are abundant at BMR and because previous studies had documented strong responses of A. oligospora to other arthropods (dead moth larvae). Soil from BMR was packed into vials (40 g dry mass equivalent per vial with water potential at −230 kPa and bulk density at 0.9 g cm−3), and one substrate or no substrate was added to the soil surface. After 30 d at 20 °C, trapping fungi were quantified by dilution plating and most probable number procedures. The response of A. oligospora was inversely related to substrate carbon:nitrogen (C:N) ratio: substrates with low C:N ratios (dead isopods, lupine leaves, dead moth larvae) usually caused large increases in A. oligospora whereas those with higher C:N ratios (isopod faeces, deer faeces, grass leaves) did not. An exception was chitin powder, which had a low C:N ratio, but which did not cause A. oligospora to proliferate. Responses of A. oligospora were directly related to the quantity of nitrogen added with each substrate, and those substrates that caused large increases in resident nematodes usually caused large increases in A. oligospora. Other trapping fungi did not respond as strongly as A. oligospora. 相似文献
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684.
House fly larvae (Musca domestica L.) grown in the residues of municipal organic waste were evaluated as a protein concentrate in practical diets for poultry. Seventy-two broiler-type chicks were alloted within 12 groups. Quadruplicate groups each received the following dietary treatments: a control diet containing soya bean meal alone, or two diets in which either 12% of the supplementary protein was provided by fly larvae meal or 9% by fish meal. The chicks were fed during the first four weeks of life with isocaloric and isoproteic diets and the results showed no significant differences in body weight gain (P > 0.05) or food conversion efficiency (P > 0.05), the larvae meal diet being intermediate to the other two. 相似文献
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Qing Lu Xurong Tang Gang Tian Fang Wang Kede Liu Vi Nguyen Susanne E. Kohalmi Wilfred A. Keller Edward W.T. Tsang John J. Harada Steven J. Rothstein Yuhai Cui 《The Plant journal : for cell and molecular biology》2010,61(2):259-270
Nuclear pore complexes (NPCs) are vital to nuclear–cytoplasmic communication in eukaryotes. The yeast NPC‐associated TREX‐2 complex, also known as the Thp1–Sac3–Cdc31–Sus1 complex, is anchored on the NPC via the nucleoporin Nup1, and is essential for mRNA export. Here we report the identification and characterization of the putative Arabidopsis thaliana TREX‐2 complex and its anchoring nucleoporin. Physical and functional evidence support the identification of the Arabidopsis orthologs of yeast Thp1 and Nup1. Of three Arabidopsis homologs of yeast Sac3, two are putative TREX‐2 components, but, surprisingly, none are required for mRNA export as they are in yeast. Physical association of the two Cdc31 homologs, but not the Sus1 homolog, with the TREX‐2 complex was observed. In addition to identification of these TREX‐2 components, direct interactions of the Arabidopsis homolog of DSS1, which is an established proteasome component in yeast and animals, with both the TREX‐2 complex and the proteasome were observed. This suggests the possibility of a link between the two complexes. Thus this work has identified the putative Arabidopsis TREX‐2 complex and provides a foundation for future studies of nuclear export in Arabidopsis. 相似文献
688.
Silvia Díaz-Fernández Javier Viñuela Beatriz Arroyo 《The Journal of wildlife management》2012,76(7):1354-1363
A basic rule to attain sustainable use of harvested resources is to adjust take to availability. Populations of red-legged partridges in Spain have decreased in recent decades, and releases of farm-bred partridges to improve short-term availability are increasingly common. We used questionnaires and bird surveys to assess whether harvest was related to availability of wild partridges or intensity of farm-bred partridge releases. We studied 50 hunting estates, including 6 administratively labeled as intensive (with few numerical and temporal restrictions to releases). In addition, we considered hunting pressure (number of hunters × hunting days/km2) and habitat as explanatory variables in the analyses. In intensive estates, annual harvest was exclusively related to release intensity, indicating that in these estates hunting is detached from natural resources and approaches an industrial activity based on external inputs. In non-intensive estates, harvest was affected by wild stock availability, walked-up shooting pressure, and habitat (greater harvest in estates with more Mediterranean shrubland). In these estates, releases did not increase annual harvest, and can be considered an inefficient practice. Additionally, the relationship between abundance estimates and harvest disappeared in estates with low partridge abundance estimates, suggesting possibilities for overharvesting in a large proportion of estates. Increasing the abundance of wild red-legged partridge through techniques like habitat management, and improving the adjustment of harvest to availability, may be a good strategy to increase long-term harvest in non-intensive estates. Additionally, Government and managers must create ways to segregate and label the estates where only wild red-legged partridges are managed from those where releases are used, to reduce ecological costs of management decisions. © 2012 The Wildlife Society. 相似文献