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1.
Birds obtained by embryo engineering are used to study embryo development and to produce transgenic birds. As this method of producing birds still generate strong emotions of the public opinion head ornaments, testes and semen characteristics of sex chimera roosters were examined to check whether they differ from chickens obtained by non‐manipulated methods. Measurements of head ornaments, testes and semen were correlated with each other. Semen quality factor (SQF) was calculated, as well as the level of fluctuating asymmetry (FA) of bilateral traits (wattles and testes). Positive correlation was found for comb width and wattle length and comb thickness and sperm concentration. Semen characteristics and FA did not exceed the level encounter in other chicken lines. Results obtained indicate that germline chimeras are similar in appearance of secondary sexual traits, and semen and testes characteristics to chickens produced in non‐manipulated way.  相似文献   
2.
In this study, we have determined serum neopterin levels in female dogs with primary malignant mammary tumours. The study involved 50 female dogs which had a malignant mammary tumours removed surgically (32 animals with carcinoma, 12 animals with sarcoma and 6 animals with carcinosarcoma) and 10 clinically healthy female dogs. Serum neopterin levels were determined using a commercial ELISA kit. The mean neopterin levels were lower in the malignant tumour groups than in healthy animals but differences were statistically significant only in carcinoma and sarcoma groups. The decrease of neopterin levels in animals with malignant mammary tumours may suggest their decreased cellular immunity. Moreover, it might indicate that decreased activity of cellular mechanisms of the anti‐neoplastic response is one of the factors associated with the development and course of malignant mammary tumours in female dogs; however, further studies are necessary.  相似文献   
3.
The aim of this article is to study the geographical distribution and historical patterns of use of a little known root crop native to Europe—marsh woundwort Stachys palustris L. The species grows in wet grasslands and arable fields. It produces edible tubers. Both ethnographic literature and archival sources were searched. Seventeen reliable references concerning the consumption of S. palustris in southern and south–eastern Poland were found. The tubers were usually dried and powdered, and then added to soups or to bread dough. They were also eaten as raw snacks. The plant was used mainly during food shortages in spring, until the turn of the nineteenth and twentieth century, and later only as an occasional raw snack until the 1970s. Marsh woundwort was also eaten in western Ukraine (one reference). There are many references to the edibility of marsh woundwort in the eighteenth and nineteenth century European economic botany literature, particularly in Sweden and Great Britain. These publications tried to popularize the use of S. palustris as food. However, there is no firm evidence from these countries that marsh woundwort was used as food there. Marsh woundwort was also used, throughout northern and central Europe, as pig fodder and as a medicinal plant, particularly for healing wounds. Further studies on the nutritive value of this forgotten crop should be undertaken, particularly that there is little knowledge of the chemical composition of both marsh woundwort and its Asian relative Stachys affinis widely cultivated in China as a vegetable.  相似文献   
4.
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   
5.
Movements of bank voles (Clethrionomys glareolus) were studied in a farmland mosaic in Poland. Distances crossed by animals in short-time periods are significantly longer in heterogenous than in homogenous habitats. In long-time and large-spatial scales, a significant portion of the animals in a population travel among habitat elements of the mosaic, reducing the degree of isolation of patch populations and decreasing the probability of local extinction.  相似文献   
6.
It is shown in this paper that cationic dyes and chemical finishing agents for textiles exhibit antimicrobial properties both in solution and when present on textile products. The dye Maxilon Navy 2RM has particularly high antimicrobial activity — its values of the minimum concentration inhibiting the growth of the studied microorganisms (MIC and MBC) are very low, in the range 0.0003–0.06 %. The tested dyes display mainly fungistatic action, while the fiber softener Sapamine OC and the dyeing fixative wet fastness improver Albafix WFF were more active against bacteria. The paper presents sensitivity series of microorganisms with respect to the tested dyes and finishing agents. Fabrics to which the substances had been applied showed reductions in microorganism numbers by 16 % to 99.9 %, depending on the type of substance and the microorganism. The studies showed that in some cases the use of a typical (justified technologically) quantity of dye or finishing agent imparts high antimicrobial activity to the textile materials, with bacteria or fungi reduced by more than 99 %.  相似文献   
7.
On the basis of the fresh weight of apple fruit and its peel and the concentration of bioactive compounds, the total quantity of L-cysteine, glutathione, ascorbate, flavonols, and anthocyanins as well as phenolics was evaluated in a wide range of cultivars and two growing seasons. Apple peel as a contributor to the entire apple quantity of the examined components considerably differed in relation to the investigated compounds and was also highly cultivar dependent. A great amount of flavonols was found in apple peel (approximately 40%), followed by ascorbate (approximately 30%) and total phenolics (approximately 20%), while the lowest contribution was assessed for thiols (approximately 11% and 14% for L-cysteine and total quantity of glutathione, respectively), based on average values for both years. Seasonal variations in the quantity of antioxidants was more pronounced in apple peel, whereas the contribution of apple peel to the whole fruit was predominantly affected by the genotype. A very high positive correlation existed between apple peel and the whole fruit quantity of antioxidants.  相似文献   
8.
The effects of two polyphenolic flavonoids (flavanone naringenin and flavonol quercetin) on development, fecundity, and mortality of the pea aphid, Acyrthosiphon pisum Harris (Hemiptera: Aphididae), were determined in vitro, on an artificial diets. Also determined in vitro (DC EPG method), on sucrose–agarose gels, were the effects of flavonoids on the probing and feeding behavior of adult apterae. When added to a liquid diet, higher concentrations of studied flavonoids increased the developmental time, the pre-reproductive period, and mortality and decreased fecundity and the intrinsic rate of natural increase of A. pisum. In most events associated with stylet activity (as indicated by EPG waveform g-C), differences in probing behavior did not statistically differ between the control gel and those with flavonoids; quercetin at 10, 100, and 1,000 µg cm?3 prolonged the number of gel penetrations; and quercetin only at 10,000 μg cm?3 prolonged the time the first g-C waveform was observed. Addition of flavonoids to the gels generally reduced passive ingestion from fluids of the gels (EPG waveform g-E2). At higher concentrations (>1,000 µg cm?3) the flavonoids completely stopped salivation (EPG waveform g-E1) and passive ingestion from fluids of the gels (EPG waveform g-E2). In events associated with active ingestion (EPG waveform g-G), however, differences in feeding behavior did not statistically differ between the control gel and those with flavonoids. The present findings demonstrate detrimental effects of the flavanone naringenin and flavonol on the behavior of the pea aphid. This can be employed in a biotechnological projects for plant breeding resistant to herbivores, including aphids.  相似文献   
9.
The effects of 3 h exposure to 96hLC50 of cadmium (4.5 mg dm−3) on oxygen consumption rate, and hematological parameters (RBC, WBC, erythrocyte and leukocyte pattern) of juvenile tench were evaluated. Oxygen consumption significantly decreased beginning from 24 h postexposure, and remained reduced until the end of the experiment (96 h postexposure). RBC gradually increased, together with the percentage of juvenile cells in circulation. On the other hand, cadmium induced damage to the red cells – the share of cellular anomalies significantly increased with time postexposure. They included abnormal cell shape, vacuolization, swelling, chromatin disintegration in the nucleus, and nucleus indentation. The exposed fish showed a gradual and significant decrease in WBC without a shift of lymphocyte/neutrophil proportion. No significant changes in thrombocyte count occurred. The results show that short-term exposure to cadmium reduced fish energetic metabolism, and suppressed immune abilities. The symptoms gradually developed after the end of exposure, and no recovery took place until␣96 h.  相似文献   
10.
Relationship between somaclonal variation and type of culture in cucumber   总被引:3,自引:0,他引:3  
Highly inbred B line of cucumber was used to compare the effect of four types of in vitro culture on somaclonal variation. The plants were regenerated from the following types of culture: twelve- and eighteen-month-old liquid culture of meristematic clumps (LMC12(18)), ten-month-old embryogenic cytokinin-dependent suspension (CDS), eighteen-month-old embryogenic cytokinin-dependent suspension in medium with modified NH+ 4/NO3 - ratio (CDS 1.7), twelve-month-old embryogenic auxin-dependent suspension (ADS), thirty six-month-old embryogenic auxin-dependent suspension in medium with modified NH+ 4/NO3 - ratio (ADS 1.7) and recurrent leaf callus regeneration (RLC) – repeated 5 times. The differences in the incidence of the following properties were observed: the ploidy of R0 plants, the segregation of new morphological traits in R1 and the germination ability of R1 seeds. R1 families with the segregation of new phenotypes were most numerous in CDS (62.5%) and LMC18 (57.9%), next in CDS1.7 (35.7%), while the smallest number was found in LMC12 (11.1%) and RLC (3.4%).Tetraploid and mixoploid plants occurred in ADS1.7 and ADS (100%) whereas CDS and RLC were observed to contain only tetraploids, respectively 33.3% and 55.2%. There were no changes of ploidy after LMC12, LMC18 and CDS1.7. Among new phenotypes there were such that have not been described so far in cucumber: ginkgolike leaf (gll), yellow-green chlorophyll mutants (y-gc), serrate margin of corolla in male and female flowers (smc). This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
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