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Franck Richard Melanie Roy Oula Shahin Christopher Sthultz Myriam Duchemin Richard Joffre Marc-André Selosse 《Annals of Forest Science》2011,68(1):57-68
• Introduction
Millions of hectares of Quercus ilex forests dominate disturbed landscapes in the western part of the Mediterranean basin. Although these forests are very widespread, little is known about the composition and structure of their associated ectomycorrhizal fungal communities. 相似文献2.
Morteza Zendehdel Keyvan Hasani Vahab Babapour Sepideh Seyedali Mortezaei Yalda Khoshbakht Shahin Hassanpour 《Veterinary research communications》2014,38(1):11-19
The present study was designed to examine the effects of intracerebroventricular (ICV) injection of Dopamine (10, 20 and 40 nmol), L-DOPA (dopamine precursor; 62.5, 125 and 250 nmol), 6-OHDA (dopamine inhibitor; 75, 150 and 300 nmol), SCH 23390 (D1 antagonist; 2.5, 5 and 10 nmol), AMI-193 (D2 antagonist; 2.5, 5 and 10 nmol), NGB2904 (D3 antagonist; 3.2, 6.4 and 12.8 nmol), L-741 T742 (D4 antagonist; 1.5, 3 and 6 nmol) on food intake in FD3 chickens. At following, birds were ICV injected using 8-OH-DPAT (5-HT1A agonist; 15.25 nmol) and SB242084 (5-HT2C antagonist; 1.5 μg) prior dopamine (40 nmol) injection. Cumulative food intake was determined until 3 h post-injection. According to the results, dopamine significantly decreased food intake in chickens (p?<?0.05). The inhibitory effect of dopamine on food intake was decreased by SCH 23390 pretreatment (P?<?0.05), but AMI-193, NGB2904 and L-741, 742 had no effect on food intake induced by dopamine. In addition, hypophagic effect of dopamine was attenuated by SB242084 (P?<?0.05), but 8-OH-DPAT had no effect. These results suggest that dopamine decrease food intake via D1 receptor and there is an interaction between dopaminergic and serotonergic systems via 5-HT2C receptor in chickens. 相似文献
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Potential N2-fixation was investigated in a number of samples representing soils and water courses under the effect of some industrial wastes in Helwan area of Egypt. Microbiological analysis of soil and water samples showed the general enrichment of fungi, actinomycetes and bacteria including N2-fixers. Among asymbiotic N2-fixers, azospirilla compared to azotobacters and clostridia were found to be present with rather higher densities in all samples tested. Generally, the microbial numbers increased by increasing the distance from the Industrial Complex at Helwan, which could be attributed to the high levels of salinity and total heavy metals near the factories. The results indicated that the industrial wastes near the factories exerted inhibitory effects on the acetylenereducing activity in soils, which seriously reduces their biological fertility. Such effects were decreased by getting away from the factories. Significantly negative correlations were recorded between densities of N2-fixers or N2-ase activity and salinity and total heavy metals content in both soil and water samples. 相似文献
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Garcia-Barros M Paris F Cordon-Cardo C Lyden D Rafii S Haimovitz-Friedman A Fuks Z Kolesnick R 《Science (New York, N.Y.)》2003,300(5622):1155-1159
About 50% of cancer patients receive radiation therapy. Here we investigated the hypothesis that tumor response to radiation is determined not only by tumor cell phenotype but also by microvascular sensitivity. MCA/129 fibrosarcomas and B16F1 melanomas grown in apoptosis-resistant acid sphingomyelinase (asmase)-deficient or Bax-deficient mice displayed markedly reduced baseline microvascular endothelial apoptosis and grew 200 to 400% faster than tumors on wild-type microvasculature. Thus, endothelial apoptosis is a homeostatic factor regulating angiogenesis-dependent tumor growth. Moreover, these tumors exhibited reduced endothelial apoptosis upon irradiation and, unlike tumors in wild-type mice, they were resistant to single-dose radiation up to 20 grays (Gy). These studies indicate that microvascular damage regulates tumor cell response to radiation at the clinically relevant dose range. 相似文献
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Felipe Pierezan Khalid Shahin Taylor I. Heckman June Ang Barbara A. Byrne Esteban Soto 《Journal of fish diseases》2020,43(4):485-490
Outbreaks of an infectious disease affecting cultured white sturgeon (Acipenser transmontanus) were investigated. Clinical signs included erratic swimming, arching of the back and mortality. Necropsy findings included poorly demarcated yellow to dark-red and friable lesions in the epaxial muscle, ulcerative skin lesions and haemorrhages in the swim bladder and coelomic wall. Histological evaluation revealed areas of necrotizing and heterophilic myositis with aggregates of bacterial cocci. The lumen of blood vessels in the dermis, under ulcerated areas, and in the posterior kidney, was occluded by fibrin thrombi. Aggregates of Gram-positive cocci were observed in the muscle lesions and within the fibrin thrombi in the dermis and kidney. Genetically homogeneous Streptococcus iniae strains were recovered from affected fish from different outbreaks. The isolates shared high degree of similarity at gene locus (gyrB) with previously characterized S. iniae from cultured fish in California, confirming the emergence of this particular strain of S. iniae in US aquaculture. 相似文献
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An objective imaging method was developed to count dark specks in spaghetti. The method simultaneously measured individual speck size and color and the overall color of the spaghetti. Spaghetti samples were prepared from durum wheat samples collected from the Prairie Registration Recommending Committee for Grains (PRRCG) durum wheat cooperative trials during four consecutive crop years from 2002 inclusive to 2005. Differences in speck counts were found between samples within each year. From year to year, the baseline for speck counts varied with the highest numbers in 2005 and the lowest numbers in 2004. For comparison, three technicians also counted the number of specks in each sample. These visual counts were not consistent between technicians or technician to the imaging method, supporting the need for this objective approach. Spaghetti speck counts did not relate to the speck counts of the semolina subsequently used to prepare the product. Speck sizes were consistent across samples and between years, indicating a consistent milling method for all the samples. Differences in speck count numbers could not be attributed to differences in speck color or pasta color. The imaging method gave very consistent speck counts and color measurements over the four years. 相似文献
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Fariba Ahmadi Morteza Zendehdel Vahab Babapour Negar Panahi Shahin Hassanpour Mina Khodadadi 《Veterinary research communications》2017,41(4):241-248
Melanocortin 3 and 4 receptors (MC3R and MC4R) are known as the main receptors for melanocortin-induced hypophagia in mammalian and poultry. Also, central glutamatergic system has mediatory role on function of the melanocortin system in some brain areas. So, the aim of the current study was to determine the role of MC3/MC4 receptors agonist on food intake and its interaction with glutamatergic in 3-h food-deprived (FD3) neonatal broilers. In experiment 1, chickens were intracerebroventricular (ICV) injected with control solution, MTII (MC3/MC4 receptors agonist; 2.45, 4.8 and 9.8 pmol). In experiment 2, control solution, SHU9119 (MC3/MC4 receptors antagonist; 0.5, 1 and 2 nmol) were ICV injected. In experiment 3, birds ICV injected with control solution, SHU9119 (0.5 nmol), MTII (9.8 pmol) and co-injection of the SHU9119 + MTII. Experiments 4–8 were similar to experiment 3, except birds injected with MK-801 (NMDA glutamate receptors antagonist, 15 nmol), CNQX (AMPA glutamate receptors antagonist; 390 nmol), AIDA (mGLUR1 glutamate receptors antagonist; 2 nmol), LY341495 (mGLUR2 glutamate receptors antagonist; 150 nmol) and UBP1112 (mGLUR3 glutamate receptors antagonist; 2 nmol) instead of SHU9119. Then, cumulative food intake was recorded until 120 min after injection. According to the results, dose dependent hypophagia observed after ICV injection of the MTII (p < 0.05). ICV injection of SHU9119 significantly increased food intake in birds (p < 0.05). Co-injection of SHU9119 + MTII significantly inhibited MTII- induced hypophagia in neonatal chicks (p < 0.05). In addition, hypophagia- induced by MTII was significantly attenuated with co-injection of MTII + MK-801(p < 0.05). These results suggested MC3 and MC4 receptors have inhibitory role on food intake and this effect is probably mediated by NMDA glutamate receptors in neonatal chickens. 相似文献