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排序方式: 共有294条查询结果,搜索用时 31 毫秒
41.
Yongxiang Kang Łukasz Jakub Łuczaj Sebastian Ye 《Genetic Resources and Crop Evolution》2012,59(7):1569-1575
Aconitum spp. are highly toxic due to the presence of aconitine-type alkaloids. Aconitum carmichaelii Debeaux is one of the most important and most studied Chinese medicines. However the scientific literature contains only anecdotal references to the use of A. carmichaelii as a food plant. The aim of the study was to document the traditional alimentary use of the species. Fifty people from three adjacent villages on Mount Taibai of the Qinling range (Shaanxi) were interviewed about the local use of the Aconitum. Most of them eat it on a regular basis every winter. The plant is widely cultivated in the area for food and nearly every family grows it. The tubers are cooked a few times during winter. Usually around 5 kg are prepared at one time and boiled, adding water four times, each time for at least 2 h, over a high flame. People usually eat one bowl a day (ca. 200 g). Respondents claim they eat them for two reasons: they heat the body in winter (they are “hot by nature”) and they are nourishing like other staples. 相似文献
42.
Tubers from eight potato cultivars (cvs) grown at two different locations in Wisconsin were tested for bacterial soft rot resistance using different inoculation techniques. The procedures included 1) point inoculations of tubers with different inoculum levels followed by incubation in ambient or low oxygen condtions, 2) inoculation of mechanically bruised tubers followed by incubation in a mist chamber, and 3) a standard slice inoculation method. The point titration test followed by incubation in dew chamber and the mist chamber-bruise test showed similar patterns of resistance for cultivars that were used in these experiments. These two methods are considered to be effective for screening potato tubers for bacterial soft rot resistance. Point titration methods are very useful if only limited numbers of tubers are available. The mist chamber-bruise test is simpler than the other procedures; however, to obtain reproducible results large numbers of tubers are required. Because of the great variability of the results obtained in inoculation of slices, the reliability of this approach can be questioned as a standardized method for evaluation of resistance. Tubers of somatic hybrids ofS. brevidens andS. tuberosum and their sexual progeny were significantly more resistant to bacterial soft rot than tubers of moderately resistant cultivars when evaluated by each of the assay procedures. 相似文献
43.
The goal of these studies was to evaluate the influence of tuber age on the expression of resistance to Phytophthora infestans in five selected potato genotypes (three cultivars and two clones) varying in tuber resistance and maturity type, and also
to select the best time for testing potato tubers for resistance to blight. Resistance was evaluated by inoculating whole
tubers at 13 different times as they progressively aged during growth and storage. Tuber age was expressed as weeks after
planting. Tubers were rated from week 13 (late July) until week 43 (late February) for tubers planted on 27–28 April, over
three consecutive seasons (2001–2003). Analysis of variance performed on tuber resistance data showed significant effects
of genotype, year and tuber age. Significant contributions of genotype × year, genotype × tuber age, year × tuber age and
year × genotype × tuber age interactions were also detected. A slight increase in tuber resistance with tuber age was observed
for cvs Bzura, Sokół and Irga, while the opposite trend was observed for the clones 97-A-63 and DG 92-227. Changes in tuber
resistance with age of tested genotypes were not related to their maturity type. The period of most stable expression of tuber
resistance was observed when tubers were tested between the 16th and 28th week after planting. 相似文献
44.
The stratigraphic rank of warming, distinguished in marine deposits as ‘marine oxygen isotope stage 7’ (MOIS 7) and recorded in terrestrial deposits as a palaeosol, has been discussed for a long time. The purpose of this paper is to describe the climate and environment of the time, determined from palaeopedological and palynological investigations of loess‐palaeosol sequences in the peri‐ and metha‐Carpathian zones, and to correlate these sequences with the Pleistocene stratigraphic units. The changes in chemical composition of the deposits were used to reconstruct the processes of chemical weathering and translocation of mobile elements during pedogenesis in three sections (Orzechowce, Galych and Velykyi Glybochok). The variability of the mean annual temperature and precipitation was estimated from the changes of elemental ratios resulting from chemical weathering and vegetation composition. From micromorphological analysis, the stages of palaeosol development and their transformation in cold periods were reconstructed. Pollen analysis carried out for the Velykyi Glyboczok, Maksymivka and Stari Kodaky sites, was used to reconstruct the vegetation cover and the temperature changes of the coldest and warmest months were calculated. The results indicate that the penultimate interglacial period, correlated with MOIS 7, comprised two warming periods separated by a profound cooling period. Warm periods were cooler than the last interglacial and more recent conditions. Vegetation was characterized by the co‐occurrence in changing proportions of patches of mixed forests and steppe vegetation. In the cold period, permafrost developed in places and cryogenic structures were formed. Regional differentiation of biotope environments, resulting from the increase in the continental nature of the climate towards the east, occurred during the whole interglacial period. 相似文献
45.
Purpose
Interestingly, soil is the component of the natural environment in which most hydrophobic organic pollution including polycyclic aromatic hydrocarbons (PAHs) gets accumulated. The aim of the present paper was to determine the effect of soil pollution with PAHs on the elemental composition, spectral properties, and hydrophobic and hydrophilic properties of humic acids. The research was performed on different types of soil samples that were artificially polluted with selected PAHs (anthracene, pyrene, fluorene and chrysene).Materials and methods
The soil samples were polluted with selected PAHs in an amount corresponding to 10 mg PAHs kg?1. The PAHs-polluted soil samples were incubated for 180 and 360 days at a temperature of 20–25 °C and fixed moisture (50 % of field water capacity). Humic acids (HAs) were extracted from the soil samples prior to the incubation (additionally, soils not polluted with PAHs) and after 180 and 360 days of incubation. For isolated HAs, the following analyses were performed: elemental composition, UV–Vis and IR spectra, susceptibility to oxidation, and hydrophilic (HIL) and hydrophobic (HOB) properties were determined using high-performance liquid chromatography.Results and discussion
The research demonstrated that introducing anthracene, fluorene, pyrene and chrysene to soil samples resulted in a change in some of the quality parameters of humic acids. However, the intensity and the direction of those changes were determined by soil properties. The changes of the parameters, once PAHs were introduced, that did not depend on the soil properties were ΔA 665u and ΔA 465u (susceptibility to oxidation at wavelengths of 465 and 665 nm) as well as HIL/ΣHOB. The same tendency in changes in the structure of humic acids, once PAHs were introduced, was also observed based on the Fourier transform infrared spectra pattern.Conclusions
A single pollution of soils with PAHs that leads to changes in the quality parameters of humic acids shows that, as for the soils permanently exposed to pollution with those compounds, significant changes can occur in the properties of humic acids. As a result, it can lead to a change in the functions played by humic acids in the environment. 相似文献46.
The aim of this paper was to determine the factors affecting the development of canine babesiosis in Poland. The studies included 800 animals from 16 polish voivodeships-districts (50 from each voivodeship) with suspected piroplasmosis. Hematological and molecular tests confirmed infections in 158 animals. Analysis of the genetic material using the Real-Time Sybr Green HRM technique showed that 96 dogs were infected with Babesia canis 18S RNA-A and 62 with B. canis 18S RNA-B. It was observed that the disease occurs more often in eastern Poland (OR: 8.91; CI: 5.7-13.8), in males (OR: 1.04; CI: 0.7-1.5) and especially in rural areas (OR: 1.7; CI: 1.2-2.4). More prone to infection were pure-bred dogs (OR: 2.24; CI: 1.6-3.2), young animals under 1 year old (OR: 0.73; CI: 0.4-1.5), animals that had suffered from babesiosis in the past (OR: 17.9; CI: 10.9-29.2) and those that had not received preventive measures against ectoparasites (OR: 0.32; CI: 0.2-0.5). Knowledge of the factors facilitating the development of canine babesiosis helps to understand the causal connection between the dogs' exposure to the pathogen and the development of the disease and to limit the occurrence of the infection in these animals, to diagnose it early and to start proper treatment before serious complications develop. 相似文献
47.
Artur Kowalczyk Ewa Łukaszewicz Tomasz Strzała Agnieszka Partyka Joanna Rosenberger 《Reproduction in domestic animals》2020,55(8):984-991
In order to increase the reproductive indices of capercaillie kept in closed breeding facilities, it is necessary to constantly expand the methods of better understanding the characteristics of sperm and their fertilizing potency. The aim of the study was to analyse selected features of capercaillie sperm using flow cytometry and their connection with fertility results. The study included five males, three of which were kept in a family group with eight females and two were kept alone. For sperm viability, acrosome integrity, mitochondrial potential and DNA defragmentation were assessed. Paternity analyses were performed in order to confirm the paternity of the individual and to link the evaluated semen traits with reproductive success. Analyses carried out in the flow cytometer showed any significant differences between males in sperm characteristics. In the semen of male No. 101, the father of all chicks from the analysed family group, 91.3% of live sperm, 91.5% with intact acrosome, 83.6% with active mitochondria and 2.0% with DNA defragmentation were observed. The average fertility rate was 71.0%, and chick hatchability was 100%. Using flow cytometry in the analysis of capercaillie semen and its connection with the results of natural mating, we were able to obtain deeper knowledge about new sperm characteristics that were not examined before and which in the future may be helpful in selecting males for the reproductive flocks and developing assisted reproduction techniques. 相似文献
48.
49.
Irene Sartini Beata Łebkowska-Wieruszewska Andrzej Lisowski Amnart Poapolathep Helen Owen Mario Giorgi 《Journal of veterinary pharmacology and therapeutics》2020,43(1):26-32
The purpose of this study was two-fold: I) to determine the pharmacokinetic profile of meloxicam (MLX) in geese after intravenous (IV) and oral (PO) administration and II) to assess tissue residues in muscle, heart, liver, lung, and kidney. Ten clinically normal female Bilgorajska geese were divided into two groups (treated, n = 8; control, n = 2). Group 1 underwent a 3-phase parallel study with a 1-week washout period. In phase I, animals received MLX (0.5 mg/kg) by IV administration; the blood was collected up to 48 hr. In phases II and III geese were treated orally at the same dosage for the collection of blood and tissue samples, respectively. Group 2 served as control. After the extraction procedure, a validated HPLC method with UV detection was used for plasma and organ analysis. The plasma concentrations were quantifiable up to 24 hr after both the administrations. The elimination phase of MLX from plasma was similar in both the administration groups. The clearance was slow (0.00975 L/hr*Kg), the volume of distribution small (0.0487 L/kg), and the IV half-life was 5.06 ± 2.32 hr. The average absolute PO bioavailability was 64.2 ± 24.0%. Residues of MLX were lower than the LOQ (0.1 µg/kg) in any tested tissue and at any collection time. The dosage used in this study achieved the plasma concentration, which provides analgesia in Hispaniolan Amazon parrots for 5 out of 24 hr after PO administration. MLX tissue concentrations were below the LOD of the assay in tissue (0.03 µg/ml). A more sensitive technique might be necessary to determine likely residue concentrations in tissue. 相似文献
50.
Jan Adamiak Arkadiusz Stępień Ewa Adamiak Dariusz Klimek 《Archives of Agronomy and Soil Science》2013,59(5):435-443
The effect of various fertilization methods on the simplified nutrients balance and changes of soil chemical features in crop rotation was estimated on the basis of 7-year (1994-2000) studies carried out on loess-based, sedimentary-gley, light-clay soil. Different fertilization methods were used: A - mineral fertilization; B - mineral and manure fertilization; C - straw, green manure and mineral fertilization; D - ecological compost and biodynamic preparation fertilization. Particular fertilization methods caused a significant differentiation of the nutrients balance. A positive phosphorus balance was found out in all the fertilization systems. It has been observed that the nitrogen and potassium carry-in with fertilizers was higher than the carry-out with crops in system B and C. A favorable calcium balance was achieved in systems C and D while a favorable magnesium balance - only in the ecologically fertilized systems (D). The changes of soil chemical features were only insignificantly dependent on the nutrient balance. After seven years of research, the contents of humus, phosphorus, potassium, magnesium and calcium increased while the soil reaction decreased in the soil of all the fertilized systems except the ecologically fertilized system. 相似文献