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961.
The study was aimed at demonstrating gender differences in the numbers, diameters and cross-section areas of muscle fibres for three hindlimb skeletal muscles responsible for locomotion and maintenance of body posture: soleus, tibialis anterior and flexor digitorum brevis in rats. The experiments were performed on five 6-month-old male and female Wistar rats. In both genders, all studied muscles of the right and left hindlimbs were isolated from surrounding tissues and excised for further procedures. The muscle transverse cross-sections taken from the muscle mid-belly were analysed. Following staining of reticular fibres by silver impregnation, the numbers, diameters and cross-section areas of muscle fibres were determined from microscopic images of muscle sections. The body mass of male rats was 80% higher than that of females. In addition, the muscle mass and the cross-section area were 53-82 and 26-45% higher in males, respectively. The number of muscle fibres was 11-42% higher in males than in females whereas the fibre diameters were 7-29% higher in males. The most conspicuous differences between males and females were found with respect to tibialis anterior, whereas the smallest differences were evident in soleus. The present study revealed that the gender morphometric differences in the studied rat hindlimb muscles were mainly owing to differences in number and size of muscle fibres and that the difference in muscle mass could be explained mainly from higher number of muscle fibres in males and to smaller degree from their larger diameters.  相似文献   
962.
Alveolar echinococcosis is a serious zoonosis caused by the larval stage of Echinococcus multilocularis. Pigs, as humans, can play the role of non-specific intermediate hosts of this parasite. Detection of E. multilocularis in swine can be taken as an indicator of infection risk for humans. This paper presents the first cases where E. multilocularis larval forms have been detected in pigs in Poland. A total of 256 pig livers with different lesions were collected from slaughterhouses in southern Poland and examined by nested PCR method. Three of them were identified as E. multilocularis positive. They contained noticeable spherical nodular whitish forms on the surface of the liver, recessed partially into the liver tissue. In two cases only single lesions (3mm and 6mm in diameter) were found, while in one case numerous (eight) lesions (2mm in diameter) were found. PCR E. multilocularis identification was confirmed by sequencing and comparison with the GenBank database.  相似文献   
963.
A new iridoid glucoside named 10-isovaleroyl-dihydropenstemide (1), along with nine known compounds was isolated from the aerial part of Penstemon campanulatus (Cav.) Willd. The known compounds include three iridoid glucosides, one phenylpropanoid glucoside, one monoterpene glucoside, one monoterpene lactone and three flavonoids. Their structures were elucidated on the basis of spectral evidence. Additionally four phenolic acids as well as a fatty acid were determined through GC-MS analysis. All isolated compounds and the crude extracts were assayed for their antimicrobial activities against six Gram positive and negative bacteria, as well as against three human pathogenic fungi.  相似文献   
964.
This paper describes the effect of the oxygen analog of ronnel (OAR) on the respiration of brain mitochondria from 4- and 16-day-old and 2- and 18-month-old rats. The oxygen analog of ronnel seems to be an uncoupler of oxidative phosphorylation in brain mitochondria derived from rats at all ages investigated. The results reported here suggest that the sensitivity of mitochondria to the uncoupling effect of OAR is an age-dependent phenomenon. Most sensitive were mitochondria isolated from brains of 18-month-old animals, while the most resistant were mitochondria derived from newborn rats (4 days old), as compared with young adult rats (2 months old). The relation between membrane structure and insecticide action is discussed.  相似文献   
965.
Factor VIII level in horse, cattle, sheep and pig plasma was estimated by the use of synthetic chromogenic substrate S-2222 (benzoyl-isoleucyl-glutamyl-glycyl-arginyl-p-nitronilide). The highest level of this factor was stated in pig, the lowest one in sheep plasma.  相似文献   
966.
The purpose of the study was the evaluation of the thermal changes within mammary gland in cows, after experimentally invoked inflammation, developed as a result of 60 ml of 20% NaCl solution given directly into the udder (A and D quarters). Three hours after injection, the increased' temperature of teats and their bases by 2.26 degrees C and 0.58 degree C, respectively, was stated. The temperature was still increased after 6 hours from NaCl solution injection. It was accompanied by increase of heat flux from the skin surface by 50.17 mW/cm2 taken from the teat surface, and by increased values of Burton Index--the tissue blood supply index.  相似文献   
967.
Bank vole, striped field mouse, wood mouse, and yellow-necked mouse populations were studied in a mosaic of field and forest habitats. Live-trapping was carried out in 8 woodlots of different sizes (1.5–9.5 ha), situated 5 to 900 m from each other and surrounded by agricultural fields. Near the study area a dense, several hundred hectare forest complex was situated. It was found that the densities of all the studied species' populations in the woodlots were positively correlated with woodlot quality. For local bank vole populations a positive correlation of density with the surface area and circumference of woodlots, as well as with the area/circumference ratio was found. A negative correlation was found for population density and the distance between a given woodlot and the forest complex. For the yellow-necked mouse a positive correlation occurred between the density of local populations and the distance to the nearest neighboring woodlot. For the striped field mouse a positive correlation was found only between the population density in each woodlot and the distance to the forest complex. The wood mouse was insensitive to the variations in woodlot features present except for woodlot quality, and hence was probably responding in density to some other factors. Four rodent species, coexisting in the field-forest habitat mosaic demonstrated different reactions to its spatial characteristics, which were mainly related to different habitat preferences, spatial behavior, and mobility of individuals of the studied species.  相似文献   
968.
Plant Foods for Human Nutrition - The aim of the study was to investigate the potential of using β-glucan as wall material to microencapsulate the elderberry extract. Firstly, the extract was...  相似文献   
969.
Purpose

The purpose of this study was to compare effects of two biostimulating substances (compost and bird droppings) on the proliferation of microorganisms, enzymatic activity, and resistance of spring barley in soil exposed to tebuconazole fungicide. Both biostimulating substances were also assessed for their efficacy in tebuconazole degradation in soil.

Materials and methods

A pot vegetation experiment was performed with soil belonging to the Eutric Cambisols to test the effect of tebuconazole on the biological activity of soil. Its adverse effect on the biological properties of soil was minimized through the use of biostimulating substances (compost and bird droppings), the effect of which was expressed with the IFC/BD index. The RCh index was used to determine the effect of tebuconazole on the proliferation of soil microorganisms and enzymes, the BA21 index was used to express soil fertility based on the activity of soil enzymes, whereas the RS index—to express the resistance of spring barley to the administered doses of tebuconazole. Finally, analyses were conducted to determine the efficacy of soil amendment with biostimulating substances in tebuconazole degradation.

Results and discussion

Study results demonstrate that tebuconazole caused significant changes in the proliferation of the tested groups of microorganisms, in the activity of soil enzymes, and in spring barley yield. It was especially noticeable in pots in which the soil was exposed to its highest dose, i.e., 2.499 mg kg?1. Soil supplementation with bird droppings had a positive effect on the development of soil microorganisms and on the enzymatic activity in the soil. In turn, compost addition to soil exerted various effects on the biological properties of soil. Both biostimulating substances failed to improve spring barley yield. Tebuconazole degradation was more intense in the soil fertilized with bird droppings than with compost.

Conclusions

Results of this study suggest that tebuconazole can affect the stability and health status of soil ecosystems by modifying their biological properties. The high sensitivity of soil microorganisms and enzymes to stress conditions makes them reliable environmental bioindicators. The strive for eliminating the adverse impact of fungicides on soil microbiome through the use of appropriate remediation methods, like, e.g., biostimulation, is of greater concern from the ecological perspective.

  相似文献   
970.
The negative impact on the environment caused by intensive agriculture has been extensively discussed for years. In particular, excessive nitrogen application has been associated with biodiversity loss. Many studies have shown the potential to reduce the use of nitrogen without any impact on crop yield. Maintaining crop yield has been the goal, whereas crop quality has not been considered. In this paper, we investigate the effect of the level of soil organic carbon (SOC) and nitrogen fertiliser application on winter wheat (Triticum aestivum) yield and its quality. We show that the absence of nitrogen fertiliser decreased both yield and quality parameters of cereal grain. Quality parameters, such as protein and gluten contents, zeleny value, falling number and hardness were strongly positively influenced by nitrogen fertiliser application. The SOC level had no significant effect on these grain quality parameters. As a result, in the absence of nitrogen fertiliser, grain was not suitable for baking bread. We recommend that in the debate on the potential to limit the use of nitrogen in agricultural production, its impact on grain quality should be taken into consideration, especially at low levels of SOC.  相似文献   
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