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排序方式: 共有187条查询结果,搜索用时 281 毫秒
31.
SARAPULTSEV Alexey RANTSEV Maxim SARAPULTSEV Petr MEDVEDEVA Svetlana DANILOVA Irina 《园艺学报》2013,29(10):1870-1876
AIM: To establish a one-stage model of experimental acute necrotizing pancreatitis (ANP) in rats characterized by the simplicity of performance and a high degree of repeatability. METHODS: ANP modeling in rats was performed based on modification of the ligation model as follows: synthetic material ligature using an atraumatic needle was performed to capture pancreatic gland ducts and marginal duodenum vessels. Ligature tips were exteriorized to the abdominal wall, and the ligature was skinned over to avoid catching intestine loops. Pancreatic macroscopic appearance and histological changes were observed. Blood biochemical and hemostatic indicators were also determined. RESULTS: Laboratory analysis of rats with experimental ANP showed a pattern of disturbances similar to that observed during pancreatic necrosis in humans as soon as the first day. General blood analysis revealed enhanced leukocytosis and alterations in leukogram characteristics, indicating acute inflammation. Serum levels of amylase, aspartate aminotransferase and creatinine significantly increased (P<0.05). Hemostatic indicators showed alterations indicating formation of disseminated intravascular coagulation, and signs of endotoxicosis were observed. These typical pancreatic necrosis patterns of disturbances were validated by the results of histological investigation. CONCLUSION: Histological changes and laboratory indicators confirm the development of a suitable model of ANP. 相似文献
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Martina Vlkova Zbynek Polesny Vladimir Verner Jan Banout Marek Dvorak Jaroslav Havlik Bohdan Lojka Petr Ehl Jitka Krausova 《Genetic Resources and Crop Evolution》2011,58(5):629-644
Ethnobotanical survey was conducted in 101 randomly selected home gardens of Phong My commune, central Vietnam, situated in the buffer-zone of Natural Reserve. Data were collected through semi-structured questionnaires and direct observation. Sixty-seven species belonging to 35 families were identified to be used for various purposes. For each species the botanical and vernacular names, plant parts used and main purposes of use are given. The major use categories reported for plant species were food (86%), medicine (32%) and firewood (32%), however, seventy-seven percent of all inventoried plants have multiple uses. The species Artocarpus heterophyllus Lam., Citrus grandis Osbeck, Citrus reticulata Blanco, Ipomoea batatas (L.) Lam. and Musa spp. were identified as the main sources of plant foods consumed within the households. Statistical analyses indicated by Shannon-Wiener and Margalef indices have shown that local species diversity and richness is affected by home garden size. On the contrary, no relationship between diversity and home garden age was found. On the basis of a cluster analysis of plant species diversity, five home garden types were differentiated. In comparison to previously reported studies on tropical home gardens, the diversity in Phong My is lower, probably due to market-oriented strategy. Nevertheless, based on the results achieved, we can conclude that useful plants cultivated in local home gardens provide valuable foods complementing daily diet and subsequently contributing to socioeconomic status of the households. 相似文献
34.
Eight organic and either inorganic magnesium (Mg) compounds (sulphate, acetate, caproate, laurate, glycine salt, L‐valine salt, L‐phenylalanine salt, and ethylene‐diaminetetraacetic acid magnesium disodium salt) were tested for Mg resorption from the leaf surface of oats (Avena sativa L. cv. Zlat'ák) and for biological availability. The plants were grown on Mg‐deficient Hoagland nutrient solution. Significant differences among the alternatives studied were found through one‐way ANOVA in all parameters of plants (top and root dry weight, Mg content in tops and roots, chlorophyll a and b content and top height). A very significant decrease of Mg content in plants and aggravation of the plant health status with increasing molar weight value (Mr) of anhydrous compound used in corresponding experimental alternative was observed. The best results were obtained in the case of magnesium sulphate (MgSO4.7H2O) (the lowest Mr value) while the worst were observed in the case of Mg laurate. A different diameter of the biggest particle necessary to be absorbed with Mg (Mg complex molecule/anion, salt anion) resulting in different mobility of this particle in water solution was proposed to be the main reason of this effect. This diameter is closely related to the Mr value of the particular compound in this case. Surprisingly, no effect of fertilizer polarity on Mg penetration was observed. The effect of complex stability of some Mg compounds on Mg penetration was also investigated. The biological availability significantly decreased with the increase of the complex strength. 相似文献
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éverton Tenório de Souza Daysianne Pereira de Lira Aline Cavalcanti de Queiroz Diogo José Costa da Silva Anansa Bezerra de Aquino Eliane A. Campessato Mella Vitor Prates Lorenzo George Emmanuel C. de Miranda Jo?o Xavier de Araújo-Júnior Maria Célia de Oliveira Chaves José Maria Barbosa-Filho Petr?nio Filgueiras de Athayde-Filho Bárbara Viviana de Oliveira Santos Magna Suzana Alexandre-Moreira 《Marine drugs》2009,7(4):689-704
The antinociceptive and anti-inflammatory activity of caulerpin was investigated. This bisindole alkaloid was isolated from the lipoid extract of Caulerpa racemosa and its structure was identified by spectroscopic methods, including IR and NMR techniques. The pharmacological assays used were the writhing and the hot plate tests, the formalin-induced pain, the capsaicin-induced ear edema and the carrageenan-induced peritonitis. Caulerpin was given orally at a concentration of 100 μmol/kg. In the abdominal constriction test caulerpin showed reduction in the acetic acid-induced nociception at 0.0945 μmol (0.0103–1.0984) and for dypirone it was 0.0426 μmol (0.0092–0.1972). In the hot plate test in vivo the inhibition of nociception by caulerpin (100 μmol/kg, p.o.) was also favorable. This result suggests that this compound exhibits a central activity, without changing the motor activity (seen in the rotarod test). Caulerpin (100 μmol/kg, p.o.) reduced the formalin effects in both phases by 35.4% and 45.6%, respectively. The possible anti-inflammatory activity observed in the second phase in the formalin test of caulerpin (100 μmol/kg, p.o.) was confirmed on the capsaicin-induced ear edema model, where an inhibition of 55.8% was presented. Indeed, it was also observed in the carrageenan-induced peritonitis that caulerpin (100 μmol/kg, p.o.) exhibited anti-inflammatory activity, reducing significantly the number of recruit cells by 48.3%. Pharmacological studies are continuing in order to characterize the mechanism(s) responsible for the antinociceptive and anti-inflammatory actions and also to identify other active principles present in Caulerpa racemosa. 相似文献
37.
1. Fowl spermatozoa incubated with DNA were used for the fertilisation of zona-free hamster oocytes. 2. Two categories of spermatozoa were detected: those which were not labelled and those which showed a very high degree of labelling (19 +/- 2% of the whole population). 3. In the hamster oocytes exposed to treated spermatozoa the labelled sperm heads were identified. 相似文献
38.
Dana Kumprechtov Josef Illek Christine Julien Petr Homolka Filip Jan
ík Eric Auclair 《Journal of animal physiology and animal nutrition》2019,103(2):447-455
The study evaluated dietary supplementation with live yeast (LY) Saccharomyces cerevisiae (CNCM I‐4407, 1010 CFU/g, Actisaf; Phileo Lesaffre Animal Care, France) on rumen fermentation and serum metabolic profile in lactating dairy cows. Fifty Holstein cows received a total mixed ration with (Live Yeast Diet, LYD, n = 25) or without (Control Diet, CD, n = 25) 5 × 1010 CFU/cow/day of LY from 3 to 19 weeks of lactation. Rumen fermentation and serum metabolic profile were measured in eight cows per treatment at 3, 7, 11, 15, 19 weeks post‐partum. LYD showed an increased daily milk yield (+4%) over CD (p < 0.05). Mean rumen pH at 4 hr after morning meal was higher in LYD (6.59) than CD (6.32) (p < 0.01). Total volatile fatty acids (VFA) and acetate molar proportion were higher in LYD (114.24 mM; 25.04%) than CD (106.47 mM; 24.73%) (p < 0.05). Propionate and butyrate molar proportions, acetate to propionate ratio, ammonia levels did not differ between LYD and CD. Ruminal lactate was lower in LYD than CD (9.3 vs. 16.4 mM) (p < 0.001), with a 53% decrease in LYD. During peak lactation, LYD had lower serum NEFA (p < 0.05, 0.40 vs. 0.48 mM) and BHBA (p < 0.01, 0.47 vs. 0.58 mM) than CD, lower liver enzyme activities (AST 1.39 vs. 1.54 ukat/L) (p < 0.05). Serum glucose was higher in LYD at peak lactation (3.22 vs. 3.12 mM, and 3.32 vs. 3.16 mM respectively) (p < 0.05). The results confirmed a reducing effect of LY on lactate accumulation in rumen fluid, associated with an increase in rumen pH. Lower serum levels of lipomobilization markers, liver enzyme activities and higher glucose levels may suggest that live yeast slightly mitigated negative energy balance and had a certain liver protective effect. 相似文献
39.
Within-field refugiums of Russian wheat aphid, Diuraphis noxia (Kurdj.) in cereals (Hom., Aphididae)
Petr Starý 《Journal of pest science》2001,74(5):124-126
An analysis of the Russian wheat aphid (RWA) (Diuraphis noxia Kurdj.), overpopulated due to extraordinary weather conditions (2000) in the Czech Republic, enabled the identification of several within-field situations ouside of the routine approach. This group, classified as within-field refugium, includes variation due to field relief, some injuries caused by the use of machinery, the unharvested field margins and, last but not least, the volunteer plants. Differences between the RWA populations in these situations and the normal grove are presented and recommended to be taken into consideration in the research on RWA population dynamics and movement. 相似文献
40.
Luo G Malkova S Yoon J Schultz DG Lin B Meron M Benjamin I Vanysek P Schlossman ML 《Science (New York, N.Y.)》2006,311(5758):216-218
Mean field theories of ion distributions, such as the Gouy-Chapman theory that describes the distribution near a charged planar surface, ignore the molecular-scale structure in the liquid solution. The predictions of the Gouy-Chapman theory vary substantially from our x-ray reflectivity measurements of the interface between two electrolyte solutions. Molecular dynamics simulations, which include the liquid structure, were used to calculate the potential of mean force on a single ion. We used this potential of mean force in a generalized Poisson-Boltzmann equation to predict the full ion distributions. These distributions agree with our measurements without any adjustable parameters. 相似文献