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The aim was to verify the effect of follicle‐stimulating hormone (FSH) supplementation to α‐MEM+ or TCM199+ media on the in vitro development of ovarian preantral follicles (PFs) derived from collared peccaries. Ovaries (n = 5 pairs) were collected and divided into fragments destined to control group (non‐cultured) or treatments that were cultured for 7 days. The PFs morphology, growth and activation were evaluated by classical histology. The immunohistochemistry markers Ag‐NOR and PCNA were used for nuclear proliferation analysis, and the picrosirius red labelling was used for ovarian extracellular matrix (ECM) evaluation. After 7‐day culture, only the TCM199+ treatment maintained the proportion of intact PFs similar to day 1 (63.2%), but no differences were found among treatments (p > .05). In addition, a significant increase in the growing follicles proportion was verified for all the treatments, indicating follicular activation (p > .05). By the Ag‐NOR analysis, only the TCM199+/FSH maintained the nuclear proliferation similar to the first day (p > .05). The picrosirius red staining revealed that the ECM remained intact in all the treatments (p > .05). We suggest the use of TCM199+ medium supplemented of FSH for the in vitro development of peccaries PFs under 7‐day culturing conditions.  相似文献   
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Abstract

In general, according to previous studies, pioneer species do not require arbuscular mycorrhizal fungi (AMF) to increase their growth and survival in tropical systems. The aim of this study was to determine the dependence response to AMF of Heliocarpus appendiculatus, a pioneer species, at different phosphorus (P) levels. In a greenhouse experiment, H. appendiculatus seedlings were grown in pots with a sterile vermiculite-sand mixture (1:1). Two sets of pots were set up: One set was inoculated (150 spores per pot) with indigenous AMF from a tropical rain forest at “Los Tuxtlas” (Veracruz, Mexico); the other set was not inoculated. To each set, 0, 0.02, 0.2, and 2 g L?1P was added. All pots were watered with 250 mL of nutrient solution. Mycorrhizal plants showed a higher total dry weight and relative growth rate in 0.02 g L?1P concentration, while nonmycorrhizal plants responded positively at 0.2 g L?1P; a decrease in plant responses at higher P levels was observed in both treatments. H. appendiculatus showed to have higher relative dependence at lower P concentration (≈50%). As levels of P increased, mycorrhizal colonization decreased. Successful growth of pioneer species during succession process may be improved if there is AMF content in soils, prior to disturbance.  相似文献   
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Woody cuttings from two Salix genotypes (genotype I—clone LUC-31, Salix alba and genotype II- clone STOTT, Salix viminalis) were grown hydroponically for 14 days at increasing concentrations of Zn: control, 50, 100 or 150 μ M Zn. Genotype tolerance to excess zinc (Zn) was evaluated using a root elongation test. The changes in growth, Zn, iron (Fe), copper (Cu) and manganese (Mn) concentrations as well as photosynthetic performance were used as additional evaluation criteria. Photosynthetic pigments concentrations in Zn-exposed cuttings of genotype II decreased as compared with genotype I, which corresponded well with the higher leaf Zn accumulation, decreased Fe concentrations as well as lowered photosynthetic rate. Based on the indicators used, genotype I (Salix alba) was classified as more tolerant to excess Zn than genotype II (Salix viminalis).  相似文献   
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Aspergillus niger-treated dry olive cake (DryOC) can be used as a soil organic amendment and the aim of this work was to study the effectiveness of this amendment and a Cd-adapted arbuscular mycorrhizal (AM) fungus in improving Trifolium repens growth and nutrition in Cd-contaminated soil. In a compartmentalized growth system, consisting of a root compartment (RC) and two hyphal compartments (HCs), we investigated the influence of the amendment on intraradical and extraradical AM fungi development. In addition, we studied the viability and infectivity of the detached extraradical mycelium in plants, designated as receptor plants, grown in the HC after removal of the RC. Both the amendment and the AM fungus increased shoot and root biomass and nodulation in both the non-contaminated and Cd-contaminated soils. The positive interaction between the microbiologically treated DryOC and the AM fungus resulted in the highest plant yield, which can be explained by enhanced nutrient acquisition and arbuscular richness as well as by the immobilisation of Cd in amended soils. However, A. niger-treated DryOC had no effect on the extraradical mycorrhizal mycelium development. Although Cd decreased AM hyphal length density, symbiotic infectivity was similar in receptor plants grown in non-contaminated and contaminated soil, thus confirming the AM fungal inoculum potential.The combination of the AM fungus and A. niger-treated DryOC increased plant tolerance to Cd in terms of plant growth and nutrition and can be regarded as an important strategy for reclaiming Cd-contaminated soils.  相似文献   
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ObjectiveTo test the effectiveness and safety of tramadol plus metamizole combined or not with a non-steroidal anti-inflammatory drug (NSAID) for treating moderate to severe chronic neoplastic pain in dogs, and its impact on quality of life (QL).Study designProspective, uncontrolled, open-label, clinical study.AnimalsSixty nine client-owned dogs with multiple forms of cancer and visual analog scale (VAS) pain score ≥40 after receiving NSAIDs for at least 7 days.MethodsThe MN group received metamizole + NSAID, MNT group received metamizole + NSAID + tramadol and MT group received metamizole + tramadol. Pain was scored by the 0 to 100 mm VAS (0 = no pain, 100 = worst pain) and analgesic therapy was considered effective if 25 mm differences in VAS scores were observed between day 0 and the follow ups. The QL was evaluated according to a 0 to 36 scoring method for dogs (0 = worst, 36 = best) and side effects were recorded. Data were registered at day 0 (baseline) and at the first and second follow ups (7 and 14 days after day 0, respectively).ResultsThe MN group had less analgesia at day 7 (25%) and day 14 (42%) than MNT (59%, p = 0.0274; 76%, p = 0.0251, respectively) and MT groups (69%, p = 0.0151; 81%, p = 0.0341, respectively). The QL scores were lower in the MN group at the first (score 23) and second follow up (score 26) than in MNT (27, p = 0.0847; 30, p = 0.0002) and MT (28, p = 0.0384; 31, p = 0.0001) groups. Side effects were more commonly observed in the MN group (87%) than in MNT (24%, p < 0.0001) and MT groups (25%, p = 0.0003) at the first follow up.Conclusions and clinical relevanceTramadol plus metamizole combined or not with NSAID were well tolerated and clinically effective to treat moderate to severe pain in dogs with cancer and improved QL.  相似文献   
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Lasing action in organic vertical-cavity surface-emitting laser (OVCSEL) structures is demonstrated. Optically pumped OVCSELs with an active layer composed of a thin-film organic semiconductor tris-(8-hydroxyquinoline) aluminum (Alq3) doped with DCM laser dye produced very narrow linewidth (0.2 +/- 0.1 angstrom), high-power (3 watts) emission that could be varied in different devices from orange to red. The efficient energy transfer from Alq3 to DCM results in a threshold input energy of 300 microjoules per square centimeter. An operational lifetime >10(6) laser pulses was achieved for a device operated well above threshold in atmosphere. The linewidths above threshold are Fourier transform-limited and could potentially be narrowed further.  相似文献   
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Tuber yield, together with tuber number and size are the basic agronomic and breeding traits in Jerusalem artichoke and can be significantly affected by environmental factors. We report the results of a long term trial on the performance of 20 Jerusalem artichoke cultivars. The random model for means with restricted maximum likelihood (REML) procedure was used to estimate the overall effects of the genotype, environment and genotype by environment interaction on traits. The partial least square regression (PLSR) model was used for modeling genotype by environment interaction variance components with a set of available correlated environmental variables. The REML variance component estimates model revealed that tuber number and yield are more dependent on GE interaction which allowed identification of best genotypes for specific environments. The PLSR model revealed that the most important climatic variables for optimal emergence, canopy development, high tuber number and yield are adequate soil and air temperatures in April. For larger tuber mass, precipitation variables and even distribution of rainfall were the most important factor, together with soil and air temperature in June when tuber growth is initiated. The knowledge obtained in this study is valuable for the identification and understanding of key environmental factors that contribute to the performance of Jerusalem artichoke.  相似文献   
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