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91.
Studies were conducted on the effects of various kinds of teleost pituitary gonadotropins on the in vitro maturation of carp oocytes. It was ascertained that after 24 h of incubation with gonadotropins, the highest percentage of oocytes with the nucleus in the migrating or peripheral position, or of mature oocytes, was observed in the case of ciprinide gonadotropins.Centrifuged hypophysial homogenates of the pike, sea-trout and pike-perch displayed a considerably weaker activity. The results obtained are indicative of a specificity of teleost pituitary gonadotropins. 相似文献
92.
Martínez-Villaluenga C Gulewicz P Pérez A Frías J Vidal-Valverde C 《Journal of agricultural and food chemistry》2006,54(19):7391-7398
Microbial population and bioactive amine profile and levels of two lupin species (Lupinus luteus L. cv. 4492 and Lupinus angustifolius L. var. zapaton) and fenugreek (Trigonella foenum-graecum L.) seeds as affected by germination were investigated. Microbial population increased considerably mainly in the first stage of germination (2 days), then small changes in bacterial numbers were observed up to 5 days to levels between 7.8 and 8.9 log colony-forming units/g. Microorganisms belonging to the Enterobacteriaceae family were dominant for the legumes tested. Ungerminated legume seeds contained putrescine, cadaverine, histamine, tyramine, spermidine, and spermine. Bioactive amine levels found in fenugreek seeds were between 3- and 4-fold higher than those found in lupin seeds. The highest total amine levels were found in fenugreek seeds [162 mg/kg of dry weight (dw)], followed by L. angustifolius var. zapaton seeds (84 mg/kg of dw) and, finally, L. luteus cv. 4492 (46 mg/kg of dw) seeds. The concentration of individual amines showed a gradual rising trend during the germination period in all tested sprouts, reaching levels >3 times higher than those found in ungerminated seeds. After 5 days of germination, the fenugreek sprouts contained the highest amount of total bioactive amines. Tyramine was the predominant amine in both lupin varieties, whereas cadaverine was the main bioactive amine detected in fenugreek. The results of this work thus indicated that microbial population and biogenic amine levels in the studied lupin and fenugreek sprouts are not a risk for healthy consumers or for individuals with restricted activity of detoxification enzymes. 相似文献
93.
Context
How do young birds achieve spatial knowledge about the environment during the initial stages of their life? They may follow adults, so gaining social information and learning; alternatively, young birds may acquire knowledge of the environment themselves by experiencing habitat and landscape features. If learning is at least partially independent of adults then young birds should respond to landscape composition at finer spatial scale than adults, who possess knowledge over a larger area.Objectives
We studied the responses of juvenile, immature and adult Caspian Gull Larus cachinnans to the same habitat and landscape variables, but at several spatial scales (ranging from 2.5 to 15 km), during post-breeding period.Methods
We surveyed 61 fish ponds (foraging patches) in southern Poland and counted Caspian gulls.Results
Juvenile birds responded at finer spatial scales to the factors than did adults. Immature birds showed complicated, intermediate responses to spatial scale. The abundance of juvenile birds was mostly correlated with the landscape composition (positively with the cover of corridors and negatively with barriers). Adult abundance was positively related to foraging patch quality (fish stock), which clearly required previous spatial experience of the environment. The abundance of all age classes were moderately correlated with each other indicating that social behaviour may also contribute to the learning of the environment.Conclusions
This study shows that as birds mature, they respond differently to components of their environment at different spatial scales. This has considerable ecological consequences for their distribution across environments.94.
Phagocytic and oxidative burst activity of phagocytic cells in peripheral blood and uterine washings in cows with clinical endometritis before and after intrauterine use of cephapirin and methisoprinol 
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下载免费PDF全文 Piotr Brodzki Urszula Lisiecka Adam Brodzki Renata Pyz‐Łukasik Leszek Krakowski 《Animal Science Journal》2018,89(10):1389-1397
The aim of the study was to evaluate phagocytic and killing activity of phagocytic cells in blood and uterine flush of cows with endometritis before and after intrauterine (i.u.) administration of cephapirin and methisoprinol. The research was carried out on 28 cows with clinical endometritis. Animals were divided into four groups, each composed of seven cows, depending on the i.u. treatment used: Group A—cephapirin; Group B—methisoprinol; Group C—cephapirin and methisoprinol at the same time; and a control group—without medication. Using flow cytometry technique, the phagocytic activity of granulocytes and monocytes was identified, as well as the oxidative burst activity of neutrophils in the peripheral blood and uterine washings. Summarizing the results of the research, i.u. infusion of cephapirin caused a reduction in the phagocytic and killing activity of phagocytes. The i.u. use of methisoprinol increased phagocytic and killing activity of phagocytes in the uterus. Administering both listed substances simultaneously showed a decrease in phagocytosis, presumably due to the dominating inhibitor effect of the antibiotic. However, also an increase of mean fluorescence intensity was observed, presumably caused by the methisoprinol. Intrauterine use of immunostimulatory substances, can improve the effectiveness of the treatment of endometritis in cows. 相似文献
95.
Purpose
The study area, located in Upper Silesian Industrial Region, was rich in significant amounts of ores that were classified of Mississippi Valley type. Being these ores especially rich in Pb and Zn, an intense development of mining and ore extraction industry was verified in this area. The goal of this study was to investigate how local pollution aureoles of As, Cd, Pb, and Zn were influenced by the presence of shallowly deposited ore-bearing dolomites.Materials and methods
Very extensive sampling campaign was carried out, and over 1,000 samples were collected in the area of about 150?km2. Local aureoles of investigated metals were calculated for two soil layers. The first one covered the part of soil core from the soil surface to the depth of 20?cm and the second one from the depth of 40?cm to the depth of 60?cm. All spatial distributions of particular metals in soil were calculated by means of ordinary kriging using free softwares QGIS and SAGA.Results and discussion
Maximum concentrations of Pb and Zn in soil in study area were very high, reaching over 24,000 and 77,000?mg/kg, respectively. Maximum concentrations of As and Cd were also very high, reaching about 1,000?mg/kg. Those maximum values were observed in the direct vicinity of the Boles?aw mine and its mine dumps. Almost all local aureoles were located within the range of ore-bearing dolomites. It was especially visible for Pb and Zn, minerals very common in ore deposits. Otherwise, local aureoles of As and Cd were more related with the vicinity of mines and other pollution sources, being more associated to the anthropogenic pollution than to the presence of ore-bearing dolomites.Conclusions
The aureoles of Pb and Zn, and in moderate degree of As, were associated with a mineral composition of ores. Differently, the location, the shape, and spatial pattern of Cd aureoles suggest that they were mostly influenced by anthropogenic pollution. Anthropogenic factors were dominating over the lithogenic ones and masking the influence of the shallowly deposited ores. 相似文献96.
Christova Petya K. Dincheva Ivaiyla N. Slavov Slavtcho B. Dobreva Ana M. Yordanova Zhenia P. Dimkova Stela D. Zaprianova Nadejda G. Atanassova Bistra Y. Sobiczewski Piotr Iakimova Elena T. 《植物病害和植物保护杂志》2021,128(6):1531-1545
Journal of Plant Diseases and Protection - The growth response of three phytopathogens to inhibitory activity of essential oils (EOs), derived from three monarda (Monarda didyma L.) genotypes, was... 相似文献
97.
98.
99.
Kwoczek M Szefer P Hać E Grembecka M 《Journal of agricultural and food chemistry》2006,54(8):3015-3024
The concentrations of 15 elements (Cu, Fe, Mn, Zn, Co, Ni, Cr, Se, Cd, Pb, Hg, Ca, Na, K, and Mg) were determined in the edible parts of shellfish on sale in the local market in Gdańsk. The samples consisted of three groups--crustaceans, molluscs, and surimi--that are processed to different degrees. For the purposes of this analysis, they were dried, homogenized, and digested in an automatic microwave system. The samples were analyzed quantitatively for Cu, Zn, Fe, Mn, Co, Ni, Cr, Mg, Na, K, and Ca (F-AAS), Cd and Pb (GF-AAS), Se (HG-AAS), and Hg (CV-AAS). The elemental levels detected in shellfish were compared to those in cod, herring, pork, beef, chicken, and eggs. The recommended dietary allowance (RDA) of essential elements and the provisional tolerable weekly intake (PTWI) of toxic elements were estimated. With factor analysis of the data, taxonomically different groups of raw and processed shellfish could be distinguished. 相似文献
100.
Rovibrational spectroscopy of molecules boasts extremely high precision, but its usefulness relies on the assignment of spectral features to corresponding quantum mechanical transitions. In the case of ortho-H(2)-CO, a weakly bound complex abundant in the interstellar medium (although not yet observed there), the rather complex spectrum has been unexplained for more than a decade. We assigned this spectrum by comparison with a purely ab initio calculation. For most lines, agreement to within 0.01 centimeter(-1) between experiment and theory was achieved. Our results show that the applicability of rovibrational spectroscopy can be extended with the assistance of high-accuracy quantum mechanical computations. 相似文献