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101.
Throughfall (TF), stemflow (SF), soil solution below the organic layer (SSorg) and at 50 cm depth (SS50), and output with stream water (SW) were measured and analyzed for four years in a moderately polluted forest catchment in southern Poland. The input of water with stemflow was ca. 6% of input with TF. However, due to higher concentrations of most ions in SF, the input of most elements with SF was from 8% to 9%. Sulphate (SO4 2–), chloride (Cl) and magnesium (Mg2+) were the only ions steadily increasing in concentrations in water percolating through the soil profile. Nitrogen reached the forest floor mainly as ammonium (NH4 +). In the soil organic layer the NH4 + concentration decreased, while concentrations of nitrate (NO3 ) and hydrogen (H+) increased, probably due to nitrification. For NO3 , sodium (Na+) and calcium (Ca2+), the highest concentrations were found in SSorg and SW. This indicates both efficient cycling in the biotic pool of the ecosystem and intensive weathering processes in the mineral soil below the plant rooting zone. The latter was especially pronounced for Mg and Ca. Concentrations of zinc (Zn), lead (Pb) and cadmium (Cd) were the highest in SSorg and SS50. As this was accompanied by a low pH and constant input of H+, NH4 + and heavy metal ions to the catchment area, it may pose a serious threat to forest health.  相似文献   
102.
In our recent studies we have evidenced that repression of ADP-ribosylation factor (ARF) in potato plants results in 14-3-3 gene activation. The significant alteration in plant phenotype and in carbohydrate content clearly indicates that there may also be changes in other metabolite syntheses. In this paper we present the data on contents of compounds, occurring in transgenic potato tubers from field trial, known to be important for the human diet. We also determine which of the ARF-antisense plant features resulted from ARF repression. This determination was accomplished by the analysis of ARF-antisense plants transformed with cDNA encoding 14-3-3 protein in reverse orientation. The sucrose accumulation and the decrease in glycoalkaloids level were found to be characteristic features of all transgenic plants. The increase in antioxidant capacity of transgenic potato tubers should also be pointed out. The analysis of fat from modified potato tubers revealed a nutritionally valuable composition of fatty acids, including the significant increase of linoleic acid level.  相似文献   
103.
A series of per-O-methylated flavonoid di- and tri-glycosides, linked with 1-2 and/or 1-6 glycosidic bonds between sugar rings that were isolated from different plant materials were analyzed. It was demonstrated that the fragmentation behavior of permethylated flavonoid glycosides is dependent on the glycosidic bond placement between sugars. Y(n) type fragment ions, created after glycosidic bond cleavage with oxygen retention on sugar at the reducing end for permethylated compounds, were observed in the normal and linked-scan mass spectra recorded for alpha(1-2) bonded conjugates of flavonoid di- and tri-glycosides. Moreover, for alpha (1-6) linked glycosides, Y fragments created after rearrangement and elimination of internal sugar residues were observed in addition to Y(n) type ions, but these fragment ions were not registered in normal desorption ionization spectra. This second type of fragmentation was also reported previously in collision-induced dissociation tandem mass spectrometry (CID MS/MS) spectra of some oligosaccharides and flavonoid glycosides, but their presence was independent of the glycosidic bonds placement between sugar rings.  相似文献   
104.
The monoculture cropping system causes significant changes within the soil ecosystem, which constitutes a habitat for soil-dwelling springtails. Focusing on the response of soil fauna to 90 years of potato cultivation in monoculture the study investigates the abundance and diversity of soil-dwelling springtails, considering changes in the soil environment in relation to five-crop rotation. Another point was the soil quality evaluation using Collembola as bioindicators (QBS-c index). A long-term monoculture experiment was established in Poland in 1923 and has continued uninterruptedly to the present time. Soil samples were taken over a period of three years (2011–2013) to determine collembolan abundance and composition, as well as physical and chemical soil properties.

The study demonstrated that there were greater numbers of Collembola in the long-term monoculture of potatoes, especially before planting time, compared to numbers in a five-field crop rotation. At the same time apparently greater species diversity was found in potato culture within crop rotation. The biological indicator of soil quality based on the occurrence of springtails (QBS-c) has proved useful in assessing changes in soil caused by agrotechnical activities. This index indicated better biological soil quality in the five-field rotation system compared to monoculture.  相似文献   

105.
Serotypes of E. coli strains isolated from piglets, which died with symptoms of diarrhea in 9 swine industrial farms, were determined. Large numbers of serotypes (from 16 to 27) in individual farms were detected. The sets of serotypes from 9 investigated farms differed among each other significantly, depending on the farm and time of examination. It was found that more than one serotype of E. coli may exist in the pig body and contribute to the development of disease. The predominant serotypes, i.e. those comprising more than 10% of serologically determined strains, were found to exist in 6 of the investigated farms and not in the remaining ones. Among the predominant serotypes, particularly important seem to be strains with K88 antigen. For prophylaxis of piglet colibacteriosis in industrial farms in Poland two vaccines for sows are recommended: one containing the K88 antigen only and the other the following serotypes: 0149:K91,K88; 020:K57; 020:K83; 0157:K88; 01:K1; 0136:K78; 024:K?; 078:K80 and 0118:K? Strains belonging to these serotypes were the most prevalent in our strain collection.  相似文献   
106.
The purpose of this work was to define more precisely the role of Ureaplasma organisms in the aetiology of granular vulvovaginitis and balanoposthitis (GVVBP) of cattle. To contribute to this question the frequency and degree of infection with Ureaplasmas in two main groups of cattle was taken into account: (a) in cattle with symptoms of the mentioned disease, (b) in cattle without clinical symptoms. The samples of semen from 301 sires with symptoms of GVVBP and from 43 healthy sires as also vaginal mucus swabs from 96 cows with GVVBP and from 40 cows mated by the sire infected with Ureaplasma organisms and from 50 cows inseminated with semen which contained Ureaplasma organisms were taken for bacteriological examinations. The control group in relation to the above mentioned cows constituted of 22 heifers free from symptoms of GVVBP and neither inseminated nor mated naturally. It has been shown that on an average 78.1% of sires with pathological changes in the mucosa of the penis or prepuce and only 25.6% of healthy sires were infected with Ureaplasma organisms. The concentration of Ureaplasma organisms was also significantly higher in material obtained from sires with symptoms of the disease than in that from healthy animals. Ureaplasma organisms were demonstrated more frequently (72.7%) in cows with GVVBP than in cows without these symptoms (13.3%). Similarly, as in the material obtained from sires, in the material taken from cows with symptoms of the disease the concentration of Ureaplasma organisms was significantly higher than that in the material originating from the healthy cows. The obtained findings may indicate that Ureaplasma organisms play a role in the aetiology of GVVBP.  相似文献   
107.
108.
109.
In tissue cultures of Populus maximowiczii Henry, Pb(NO3)2 had a restraining effect on fresh weight increase and anthocyanin content. In ultrastructural research Pb deposits of various size were mainly present in the intercellular spaces, cell walls (mainly in the region of the middle lamella), in the paramural bodies and in the vacuoles. Small deposits of this metal were also observed in the endoplasmic reticulum (ER), dictyosomes and dictyosome derivated vesicles.  相似文献   
110.
The effect of Ferrodex, vitamin A and synthetic beta-carotene on the content of iron and copper in the blood serum has been investigated in three groups of calves: I control group without vitamin supplements, II group received only once with the first colostrum dose 1.5 million IU of vitamin A, III group received Rovimix beta carotene containing 10 per cent of the synthetic beta carotene with Mlekomix from the 21st day to the 13th week of life. Moreover half of the calves from each group received Ferrodex intramusculary. Content of iron, total iron binding capacity by serum proteins, level of indirect and direct copper as well as the content of ceruloplasmin were determined in the blood serum of calves. Moreover hematocrit and hemoglobin content in the blood were determined. The results obtained show that a triple intramuscular injection of Ferrodex caused an increase of the level of iron, copper and ceruloplasmin in the blood serum of calves. However, a single administration of vitamin A to the calves or a continuous administration of Rovimix beta-carotene decreased significantly the level of iron and ceruloplasmin copper in blood serum as well as caused a more dynamic ceruloplasmin synthesis with a simultaneous increase in its utilization.  相似文献   
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