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31.
In spite of a lack of acute toxicity of single metal ions, in 96 hour laboratory tests there was a long term toxicity againstS. carpocapsae andH. bacteriophora nematodes. The 96 hour laboratory tests were carried out in order to prove possible synergistic and antagonistic interactions between pairs of metal ions. Thus, the pairs of ions were arranged from each of Al, Cd, Co(II), Cr(III), Cr(VI), Cu(II), Fe(III), Li, Mo(VI), Ni(II), Sc(IV), V(V) and Zn on one side and Mn(II) and Mg on the other. Mn(II) and Mg ions considerably reduced the nematode mortality and increased their infectivity againstGalleria mellonella caterpillars.  相似文献   
32.
The influence of procyanidin extract from Japanese quince fruit on the activities of matrix metalloproteinases MMP-2 and MMP-9 secreted to culture medium by human peripheral blood mononuclear cells (PBMC) and by human leukemia HL-60 cells was investigated by gelatin zymography. The extract proved to be an effective inhibitor of the enzymes activities (for MMP-2 and MMP-9 secreted by PBMC IC50 = 16-19 microg extract/mL and 22-25 microg extract/mL, respectively). To identify the most effective components of the extract it was fractionated by means of column chromatography on TSKgel Toyopearl HW-40 (S) bed. The obtained fractions were analyzed by TLC, HPLC, and MALDI-TOF MS. Their antioxidant activity was measured as cation radicals ABTS(.+) scavenging efficiency. The fractions VIII-XIV containing oligomers from trimer to hexamer (and probably higher oligomers) appeared to be the most effective inhibitors of MMP-2 and MMP-9 activity (IC50 value close to 4.6 microg total polyphenols/mL). To the best of our knowledge, it is the first report on gelatinase-inhibitory activity of Japanese quince fruit polyphenol extract. We conclude that polyphenols from Japanese quince can be used in cancer chemoprevention, although further studies are needed to elucidate the mechanisms underlying their biological activities.  相似文献   
33.
Folates (B vitamins) are essential for the proper function of many bodily processes. Although a rich natural source are vegetables, the literature lacks data on the effect of the pre-treatment and freezing technologies used in vegetable processing and frozen storage time on the folate content in these materials. Moreover, since folates are very unstable nutrients, the amount available in processed and stored foods can be significantly lower than in raw products. In tested vegetables (green beans, yellow beans, peas, cauliflower, broccoli and spinach), one folate form was identified, 5-methyltetrahydrofolate (5-CH3-H4folate). It was observed that pre-treatment and freezing technology significantly (p?<?0.05) decreased 5-CH3-H4folate content only in vegetables with the largest degree of fragmentation (cut and briquetted spinach) and the smallest size (peas). In all analyzed samples, the 5-CH3-H4folate content decreased with the time of frozen storage. In frozen cauliflower, the 5-CH3-H4folate loss exceeded 95 % compared to the fresh product just after the third month of frozen storage. Meanwhile, in green and yellow beans, significant 5-CH3-H4folate losses (at the level of 75 % and 95 %, respectively) were observed no earlier than after the 9th month of frozen storage.  相似文献   
34.
The effects of cadmium and copper on activity of common carp head kidney hematopoietic tissue were evaluated. The fish were subjected to short-term (3 h, Cd-s and Cu-s) or long-term (4 weeks, Cd-l and Cu-l) exposures to 100 % 96hLC50 or 10 % 96hLC50, respectively. Head kidneys were isolated weekly from 5 fish of each group for 4 weeks (post-short-term exposure and during long-term exposure). Percentage of early blast cells among the hematopoietic precursors was calculated. Proliferative and apoptotic activity were evaluated using immunocytochemical staining for proliferating cell nuclear antigen (PCNA) and caspase 3, respectively. Hematopoietic activity was calculated as the ratio of proliferating to apoptotic cells. All metal exposures induced an increase in frequency of early blast cells. The frequency of proliferating (PCNA-positive) cells also significantly increased. A considerable and significant increase in the frequency of apoptotic cells was the most pronounced effect of metal exposures. Both short-term and long-term treatments caused similar effects, but in case of Cd exposures, the reaction was more pronounced. All metal exposures reduced hematopoietic potential of fish measured as the ratio of proliferating to apoptotic precursor cell frequency. However, in all cases, hematopoietic activity was higher than 1 showing that the rate of repair of hematopoietic tissue prevailed over destruction.  相似文献   
35.
Doubled haploid (DH) production is valuable technology in modern plant breeding of oilseed rape. Doubled haploids can be produced from in vitro isolated and cultured microspores, which, instead of forming pollen, develop into haploid embryos. Either spontaneously or after artificial doubling of chromosomes, the arising resulting plants are diploid and fertile, and 100% homozygous for all genes. Biotechnological DH production offers various advantages for plant breeders, including the possibility to obtain homozygous lines rapidly, as well as easy selection due to the absence of heterozygosity. A DH line with desirable agronomic characters can be chosen and introduced into a breeding program as a result of selection for a combination of optimum characters. The study presents the application of uni- and multi-variate statistical methods to evaluate winter oilseed rape DH lines studied in a series of six experiments repeated at different localities and over a number of years. These methods made it possible to estimate individual DH lines under various environmental conditions, including the assessment of the content and stability of two different fatty acid compositions. The aim of the study was to classify and select the best oilseed rape genotypes with regard to the requirements of chemical and biodiesel industry concerning fatty acid compositions at simultaneously high seed yield. The paper contains the results of statistical analysis of 37 genotypes (32 DH lines, 2 parental forms, F2 and F3 hybrids and standard cultivar) performed on the basis of experiments carried out at 6 environments. A total of 14 genotypes were found satisfactory (11 stable and 3 unstable) for the chemical industry and 10 genotypes satisfactory (6 stable and 4 unstable) for the biodiesel industry. Among them 5 genotypes had very profitable significant and positive estimates of the main effect for seed yield.  相似文献   
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