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1.
Obesity is the common nutritional disorder affecting more and more animals every year. Obese individuals have altered metabolism and disorders of many organs. Obesity may develop as a result of specific genetic, metabolic, nervous and environmental factors. Dietary management of obesity requires addressing the underlying metabolism of the animal, normalizing the glucose level and proper treatment of diabetes, which is usually associated with obesity. Novel nutrients like leptin, chromium, carnitine and starch added to the diet as well as new approaches in the obesity therapy are very important in successful weight management and treatment of this common disorder.  相似文献   
2.
β-Glucosidase (β-1,4-D-glucoside glucohydrolase: EC.3.2.1.21) catalyzes the hydrolysis of β-glucosidic bonds between saccharides and aryl or alkyl groups. A gene encoding β-glucosidase from Bacillus licheniformis KCTC 1918, an anaerobic spore-forming soil bacterium, was cloned and characterized. The structural gene for the β-glucosidase consists of 1410 bp encoding 469 amino acid residues, and has a molecular weight of 53.4 kDa as estimated by sodium dodecyl sulfate polyacrylamide gel electrophoresis with 12% separating gel. The enzyme activity was determined against pNPG as a substrate. The enzyme was optimally active at pH 6.0 (citrate-phosphate buffer) and 47°C. β-Glucosidase retained 100% of its original activity for 24 h. The activity of the enzyme was stimulated by glycerol and urea and was decreased by Ca2+, Cu2+, Hg2+, Mg2+, and Mn2+. In particular, Cu2+ had the strongest negative effect on β-glucosidase activity. The purified β-glucosidase was active against pNPG and cellobiose. When the β-glucosidase was tested for cellulose hydrolysis, the supplement of β-glucosidase with cellulose increased the glucose yield from pine wood powder by 139.8%.  相似文献   
3.
The aim of the study was to evaluate the anatomo- and histopathological lesions in internal organs of sows and their stillborn piglets after experimental Y. enterocolitica infection in different phases of pregnancy. Twelve pregnant sows were divided into 4 groups, infected per os on 33 (n = 3), 54 (n = 3) and 89 (n = 3) day of pregnancy with the pathogenic Y. enterocolitica strain isolated from the aborted swine fetus, and uninfected control group. Histopathological examinations of internal organs and intestine samples of stillborn piglets, slaughtered sows and samples of placentas were performed. Anatomo- and histopathological lesions were the most intense in the group of sows infected in the final phase of pregnancy, where the highest number of stillborn piglets was also found. Lesions of internal organs in stillborn piglets suggested a severe generalized bacterial infection. Although the analysis of experimental Y. enterocolitica infection of pregnant sows revealed that the most intense clinical, anatomopathological and histopathological abnormalities were recorded in the group of animals infected in the final phase of pregnancy. Infection in the first phase of pregnancy could have had an influence on the formation of the granulomatous inflammation. Differences in anatomopathological lesions between infected and control animals suggest that the period of pregnancy in which the infection appears could have had an influence on the course of yersiniosis in pigs.  相似文献   
4.
Average values of chosen haematological parameters have been described in a population of 90 clinically normal Polish Primitive Horses. The comparison of the results with values given in literature for horses as a whole and for other breeds enabled us to state that Polish Primitive Horses' blood is characterized by relatively low values of RBC, PCV, segmented neutrophils and monocytes, and high percentage of lymphocytes. It was demonstrated that values of some blood parameters of examined animals are similar to typical results obtained for primitive and cold-blooded horses. Moreover, it was proved that age, sex, and season have influence upon many blood parameters' values of the Polish Primitive Horses. More precise evaluation of results received with that breed will be possible when that influence is taken into consideration.  相似文献   
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6.
Auto- and alloplasmic doubled haploid (DH) lines of barley were examined for susceptibility to Fusarium culmorum (W.G.Sm.) Sacc. (isolate KF350) seedling blight. Inoculated kernels were incubated at 20 °C in a chamber saturated to 100% RH a with 12/12 h dark/light cycle. Germination capacity, disease score on a 5-degree scale and root length were evaluated. The data were analysed statistically using three-factor analysis of variance. It was observed that the infection score of roots of DH lines with H. bulbosum cytoplasm was higher than that of their autoplasmic analogues. Length of infected seedling roots expressed as per cent of the control root length ranged from 81 to 56% in autoplasmic DH lines and from 60 to 48% in alloplasmic lines. These differences were statistically significant (at P = 0.01). It was evident, that H. bulbosum cytoplasm increase susceptibility of barley genotypes to Fusarium seedling blight.  相似文献   
7.
Polycyclic aromatic hydrocarbons and heavy metal (Pb, Cd, Cu, Zn, Hg, Fe, Co, Cr, Mo) contents were established in soil and plant samples collected in different areas of the railway junction I?awa G?ówna, Poland. Soil and plant samples were collected in four functional parts of the junction, i.e. the loading ramp, main track within platform area, rolling stock cleaning bay and the railway siding. It was found that all the investigated areas were strongly contaminated with polycyclic aromatic hydrocarbons (PAHs). The PAH contamination of the soil was the highest in the railway siding and in the platform area (59,508 and 49,670?μg?kg(-1), respectively). In the loading ramp and cleaning bay, the PAH concentration in soil was lower but still relatively very high (17,948 and 15,376?μg?kg(-1), respectively). The contamination in the railway siding exceeded the average control level up to about 80 times. In the soil of all the investigated areas, four- and five-ring PAHs prevailed. The concentrations of PAHs were determined in four dominating species of plants found at the junction. The highest concentration was found in the aerial parts of Taraxacum officinale (22,492?μg?kg(-1)) growing in the cleaning bay. The comparison of the soil contamination with PAHs in the investigated railway junction showed a very significant increase of the PAHs level since 1995. It was found that the heavy metal contamination was also very high. Pb, Zn, Hg and Cd were established at the highest levels in the railway siding area, whereas Fe concentration was the highest in the platform area. A significant increase in mercury content was observed in the cleaning bay area. The investigations proved very significant increase of contamination with PAHs and similar heavy metals contamination in comparison with the concentration determined in the same areas 13?years ago.  相似文献   
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9.
本实验从内蒙古半荒漠草原带达茂联合旗和苏尼特右旗的牧民家庭中采集乳样,进行乳酸菌的分离和生物学特性的研究。从乳样中共分出44株乳酸菌,其中乳链球菌2株,占分离总数的4.4%,乳脂链球菌1株,占分离总数的2.3%。所测试的菌株符合相应菌属和种的形态、染色特性和生化反应标准,同一种的不同菌株间的糖发酵试验有一定的差异。  相似文献   
10.
The demand for Japanese larch (Larix leptolepis) seeds has increased in Korea but their supply has been limited due to sporadic natural seed production. Among the various flower induction techniques, girdling woody stems has been recognized as a simple and efficient method to enhance seed production in a number of conifers. In this study, stem girdling was applied to 42-year-old Japanese larches, resulting in remarkable enhancement of seed cone production with no morphological changes in the seed characteristics. Metabolic alterations in needles of the girdled and the control trees were interrogated by using 23 individual metabolites including soluble sugars, polyamines and amino acids. In the girdled trees, the contents of both soluble sugars and polyamines were higher from June to July and then became similar to those in the control. The levels of amino acids were significantly increased only in August by girdling compared to the non-girdled trees. In control larch trees, the dominant amino acids were changed from Glu and Ala until July to Asp and Tyr in August. Interestingly, the concentrations of Asp-derived amino acids such as Lys, Met and Thr, were increased by girdling and they also showed significant correlations with the number of seed cones per trees, suggesting that the enhanced levels of three amino acids might positively influence on the development of seed cones in girdled larch trees. Although the role of Asp-derived amino acids on enhanced seed cone production remains unclear, the approach presented in this study might provide useful information in elucidating metabolic network modulation induced by girdling and will be further applied for enhanced seed cone production in Japanese larch trees.  相似文献   
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