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1.
Production of trichothecene and non-trichothecene mycotoxins by Fusarium species isolated from maize in Minnesota 总被引:1,自引:0,他引:1
Eighty-two cultures of Fusarium species isolated in 1986 from moldy maize in Minnesota were each cultured on rice for 4 weeks and found to produce the following mycotoxins: F. graminearum isolates, deoxynivalenol (DON, 4–225 g/g), 3-acetyldeoxynivalenol (3-ADON, 2–4g/g), 15-acetyldeoxynivalenol (15-ADON, 1–35 g/g) and zearalenone (ZEA, 5–4350 g/g); F. moniliforme, fusarin C (detectable amounts to 1000 g/g); F. mòniliforme, F. oxysporum, F. proliferatum and F. subglutinans isolates, moniliformin (15–6775 g/g); F. moniliforme, F. proliferatum, and F. subglutinans isolates, fusaric acid (detectable amounts). Other mycotoxins screened for in each rice sample and not detected were T-2 toxin, HT-2 toxin, neosolaniol, T-2 tetraol, nivalenol, fusarenon-X, scirpenols, alpha and beta trans-zearalenols, wortmannin, and fusarochromanone. The rat feeding bioassay indicated that other, unidentified toxins may be present. 相似文献
2.
H-thymidine was injected into cytoplasm of the eggs taken at different intervals after fertilization and the eggs were fixed immediately thereafter. DNA synthesis was shown to begin in pronuclei when they are still in the marginal zones of cytoplasm, immediately after their formation. S-phase lasts 5-6 h in every pronucleus and is terminated at 1-2 h before the first cleavage division when the pronuclei are closely approached and located in the center of cytoplasm. At the end of S-phase late replicating heterochromatic regions are distinctly localized near the nuclear envelope and in pronuclei. Male and female pronuclei display asynchrony in the course of S-phase and differences in 3H-thymidine incorporation into chromatin. Structural features of the first cell cycle in mouse embryogenesis are discussed. 相似文献
3.
In the context of pandemic influenza, the prompt and effective implementation of control measures is of great concern for
public health officials around the world. In particular, the role of vaccination should be considered as part of any pandemic
preparedness plan. The timely production and efficient distribution of pandemic influenza vaccines are important factors to
consider in mitigating the morbidity and mortality impact of an influenza pandemic, particularly for those individuals at
highest risk of developing severe disease. In this paper, we use a mathematical model that incorporates age-structured transmission
dynamics of influenza to evaluate optimal vaccination strategies in the epidemiological context of the Spring 2009 A (H1N1)
pandemic in Mexico. We extend previous work on age-specific vaccination strategies to time-dependent optimal vaccination policies
by solving an optimal control problem with the aim of minimizing the number of infected individuals over the course of a single
pandemic wave. Optimal vaccination policies are computed and analyzed under different vaccination coverages (21%–77%) and
different transmissibility levels (R0\mathcal{R}_{0} in the range of 1.8–3). The results suggest that the optimal vaccination can be achieved by allocating most vaccines to young
adults (20–39 yr) followed by school age children (6–12 yr) when the vaccination coverage does not exceed 30%. For higher
R0\mathcal{R}_{0} levels ($\mathcal{R}_{0}>=2.4$\mathcal{R}_{0}>=2.4), or a time delay in the implementation of vaccination (>90 days), a quick and substantial decrease in the pool of susceptibles
would require the implementation of an intensive vaccination protocol within a shorter period of time. Our results indicate
that optimal age-specific vaccination rates are significantly associated with R0\mathcal{R}_{0}, the amount of vaccines available and the timing of vaccination. 相似文献
4.
Mirosław Mleczek Iwona Rissmann Paweł Rutkowski Zygmunt Kaczmarek Piotr Golinski 《Environmental and Experimental Botany》2009,66(2):289-296
The aim of this study was to assess the accumulation of seven heavy metals (lead, cadmium, copper, zinc, chrome, nickel and cobalt). The investigations were conducted on twelve genotypes of willows which grow in the Potasze Forest Division Salicarium. The analysis facilitated quantification of concentrations of selected metals in plants and their comparison in relation to sorption ability of each willow genotype. Simultaneously the studies allowed us to demonstrate essential differentiation of metal size sorption within the species Salix purpurea and in relation to the other genotypes. The results confirm the complexity of factors influencing the efficiency of heavy metal accumulation by willow; they indicate increasing ion absorption in the case of some metals, while the accumulation of other heavy metal ions was limited. 相似文献
5.
At anthesis, under field conditions at Fundulea, each of 6 Romanian winter wheat genotypes was inoculated with 3Fusarium graminearum isolates used individually.Fusarium head blight (FHB) was assessed according to the following traits: relative weight of spikes (RWS), percentage of Fusarium
damaged kernels (FDK), relative weight of kernels per head (RWKH), area under the disease progress curve (AUDPC) and deoxynivalenol
(DON) content in total sample of kernels. Correlations between these traits and parameters revealed important differences
between examined wheat genotypes in: DON accumulation, progress of FHB development, yield reduction, and models of host —
pathogen interactions in theTriticum - Fusarium pathosystem. Significant correlations between different attributes of FHB were found forFusarium isolate 1 which is a moderate producer of DON (0.89 μg g-1). Weight of spike was significantly correlated with weight of kernels per spike (r = 0.93**) and with percentage of damaged
kernels (r = - 0.87**), while FDK was highly correlated with RWKH (r = - 0.85*) and with DON content (r = 0.82*). Area under
the disease progress curve was also found to be significantly correlated with DON content (r = 0.86*). 相似文献
6.
Engoren Milo Rochlen Lauryn R. Diehl Matthew V. Sherman Sarah S. Jewell Elizabeth Golinski Mary Begeman Paul Cavanaugh John M. 《BMC anesthesiology》2017,17(1):1-5
Dexmedetomidine is a highly selective adrenergic receptor agonist, which has a dose-dependent sedative hypnotic effect. Furthermore, it also has pharmacological properties, and the ability to inhibit sympathetic activity and improve cardiovascular stability during an operation. However, its protective effect on patients with severe craniocerebral injury in the perioperative period remains unclear. Eighty adult male SD rats were used and divided into two groups (n = 40, each group): dexmedetomidine injury group (experimental group), and sodium chloride injury group (control group). Models of severe craniocerebral injury were established in these two groups using the modified Feeney’s free-fall method. As soon as the establishment of models was succeed, rat in the experimental group received 1 μg of dexmedetomidine (0.1 ml), while each rat in the control group was given 0.1 ml of 0.9% sodium chloride. Blood was sampled from an incision at the femoral vein to detect TNF-α and IL-2 levels at 1, 12, 24,36,48 and 72 h after establishing the model in the two groups. After severe craniocerebral injury, TNF-α levels of rats were lower in every stage and at different degrees in the experimental group than in the control group (P < 0.05), while IL-2 levels were lower in the experimental group to different extents (P < 0.05). Dexmedetomidine protects the brain of rats with severe craniocerebral injury by reducing the release of inflammatory mediators. 相似文献
7.
Simultaneous analysis of beauvericin and moniliformin in fungal cultures and in cereal grain samples
Species ofFusarium subglutinans andFusarium proliferation have been found to produce two mycotoxins, beauvericin and moniliformin, under labolatory conditions as well as in infected
ears. A method for simultaneous extraction, analysis and quantitation of both metabolites was elaborated. Recoveries were
85–97 % and 78–94 % for the first and the latter mycotoxin, respectively. Detection limit of beauvericin on high- performance
thin- layer chromatography plates (Merck 5633) after exposure to iodine vapours was 3 μg/g and by high- performance liquid
chromatography method 0.07 μg/g while moniliformin was analyzed at concentration level 1 μg/g by thin- layer chromatography
and 0.05 μg/g by high- performance liquid chromatography method. 相似文献
8.
Walter S Kostpopoulos P Haass A Helwig S Keller I Licina T Schlechtriemen T Roth C Papanagiotou P Zimmer A Viera J Vierra J Körner H Schmidt K Romann MS Alexandrou M Yilmaz U Grunwald I Kubulus D Lesmeister M Ziegeler S Pattar A Golinski M Liu Y Volk T Bertsch T Reith W Fassbender K 《PloS one》2010,5(10):e13758
Background
Early treatment with rt-PA is critical for favorable outcome of acute stroke. However, only a very small proportion of stroke patients receive this treatment, as most arrive at hospital too late to be eligible for rt-PA therapy.Methods and Findings
We developed a “Mobile Stroke Unit”, consisting of an ambulance equipped with computed tomography, a point-of-care laboratory system for complete stroke laboratory work-up, and telemedicine capabilities for contact with hospital experts, to achieve delivery of etiology-specific and guideline-adherent stroke treatment at the site of the emergency, well before arrival at the hospital. In a departure from current practice, stroke patients could be differentially treated according to their ischemic or hemorrhagic etiology even in the prehospital phase of stroke management. Immediate diagnosis of cerebral ischemia and exclusion of thrombolysis contraindications enabled us to perform prehospital rt-PA thrombolysis as bridging to later intra-arterial recanalization in one patient. In a complementary patient with cerebral hemorrhage, prehospital diagnosis allowed immediate initiation of hemorrhage-specific blood pressure management and telemedicine consultation regarding surgery. Call-to-therapy-decision times were 35 minutes.Conclusion
This preliminary study proves the feasibility of guideline-adherent, etiology-specific and causal treatment of acute stroke directly at the emergency site. 相似文献9.
Traditional metapopulation theory classifies a metapopulation as a spatially homogeneous population that persists on neighboring habitat patches. The fate of each population on a habitat patch is a function of a balance between births and deaths via establishment of new populations through migration to neighboring patches. In this study, we expand upon traditional metapopulation models by incorporating spatial heterogeneity into a previously studied two-patch nonlinear ordinary differential equation metapopulation model, in which the growth of a general prey species is logistic and growth of a general predator species displays a Holling type II functional response. The model described in this work assumes that migration by generalist predator and prey populations between habitat patches occurs via a migratory corridor. Thus, persistence of species is a function of local population dynamics and migration between spatially heterogeneous habitat patches. Numerical results generated by our model demonstrate that population densities exhibit periodic plane-wave phenomena, which appear to be functions of differences in migration rates between generalist predator and prey populations. We compare results generated from our model to results generated by similar, but less ecologically realistic work, and to observed population dynamics in natural metapopulations. 相似文献
10.
Male sexual behavior depends on gonadal androgens in species of all major vertebrate lineages, including reptiles. However, male sexual behavior includes distinct appetitive and consummatory phases, typically denoted as courtship and mounting, with potentially different hormonal control. Different proximate controls of courtship versus mounting could enable disconnected evolutionary losses and gains of various aspects of male sexual behavior. Male courtship display, which is activated by testosterone (T) in many species, is an ancestral trait in the lizard family Eublepharidae. However, Coleonyx elegans (Yucatan Banded Gecko) lost the courtship display, while retaining a highly simplified male sexual behavior that involves only mounting for copulation. We performed surgical manipulations (castration with and without T replacement in adult males; implantation of adult females with exogenous T) to investigate hormonal mechanisms involved in this evolutionary novelty. Our results indicate that the expression of simplified sexual behavior in C. elegans does not require elevated circulating levels of T, a finding that is previously unreported in lizards. In females, however, exogenous T induced male-like mounting. Thus, the mounting phase of sexual behavior is not activated by T in the traditional sense of this term but probably requires post-natal, maturational organization (if not periodic reorganization) by androgens. We conclude that the simplification of male sexual behavior and its independence from elevated levels of circulating androgens in C. elegans evolved via 1) evolutionary loss of the androgen-activated courtship display and 2) retention of the mounting phase, which has a longer “functional memory” for the effects of androgenic steroids. 相似文献