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31.
Stanca L Petrache SN Radu M Serban AI Munteanu MC Teodorescu D Staicu AC Sima C Costache M Grigoriu C Zarnescu O Dinischiotu A 《Fish physiology and biochemistry》2012,38(4):963-975
Silicon-based quantum dots were intraperitoneally injected in individuals of Carassius auratus gibelio. Their effects on white muscle were investigated by following their distribution and impact on the antioxidative system. The GSH level significantly increased after 1 and 3?days of exposure by, respectively, 85.3 and 25.4%. Seven days later, GSH levels were similar to control concentrations. MDA concentration rose after three days by 46.9% and remained at the same level after 7?days. Protein thiol levels significantly decreased by 6.7 and 8.1% after 3 and 7?days, whereas advanced oxidation protein products increased by 12.7, respectively, 28.1% in the same time intervals. The protein reactive carbonyl groups were raised only after the first day of exposure and returned to the control level later on. SOD specific activity increased up to 48% after 7?days, while CAT activity increased by 328, 176, and 26% after 1, 3, and 7?days of treatment. GST specific activity was up-regulated by 87, 18, and 9%, while GR activity increased by 68, 34, and 9%. G6PD activity was up-regulated by 12, 22, and 50%, whereas GPx activity raised by 75 and 109% compared to control after, respectively, 1, 3, and 7?days. Our results suggest that oxidative stress induced by silicon-based quantum dots was not strong enough to cause permanent damage in the white muscle of crucian carp. 相似文献
32.
PenTing Liao Melissa Sinclair Alexander Valverde Cornelia Mosley Heather Chalmers Shawn Mackenzie Brad Hanna 《Veterinary anaesthesia and analgesia》2017,44(5):1016-1026
Objectives
To compare propofol and alfaxalone, with or without midazolam, for induction of anesthesia in fentanyl-sedated dogs, and to assess recovery from total intravenous anesthesia (TIVA).Study design
Prospective, incomplete, Latin-square study.Animals
Ten dogs weighing 24.5 ± 3.1 kg (mean ± standard deviation).Methods
Dogs were randomly assigned to four treatments: treatment P-M, propofol (1 mg kg?1) and midazolam (0.3 mg kg?1); treatment P-S, propofol and saline; treatment A-M, alfaxalone (0.5 mg kg?1) and midazolam; treatment A-S, alfaxalone and saline, administered intravenously (IV) 10 minutes after fentanyl (7 μg kg?1) IV. Additional propofol or alfaxalone were administered as necessary for endotracheal intubation. TIVA was maintained for 35–55 minutes by infusions of propofol or alfaxalone. Scores were assigned for quality of sedation, induction, extubation and recovery. The drug doses required for intubation and TIVA, times from sedation to end of TIVA, end anesthesia to extubation and to standing were recorded. Analysis included a general linear mixed model with post hoc analysis (p < 0.05).Results
Significant differences were detected in the quality of induction, better in A-M than A-S and P-S, and in P-M than P-S; in total intubation dose, lower in P-M (1.5 mg kg?1) than P-S (2.1 mg kg?1), and A-M (0.62 mg kg?1) than A-S (0.98 mg kg?1); and lower TIVA rate in P-M (268 μg kg?1 minute?1) than P-S (310 μg kg?1 minute?1). TIVA rate was similar in A-M and A-S (83 and 87 μg kg?1 minute?1, respectively). Time to standing was longer after alfaxalone than propofol, but was not influenced by midazolam.Conclusions and clinical relevance
Addition of midazolam reduced the induction doses of propofol and alfaxalone and improved the quality of induction in fentanyl-sedated dogs. The dose rate of propofol for TIVA was decreased. 相似文献33.
Dirk Jungmann Cornelia Bandow Thomas Gildemeister Roland Nagel Thomas G. Preuss Hans T. Ratte Cândida Shinn Lennart Weltje Hanna M. Maes 《Journal of Soils and Sediments》2009,9(2):94-102
Background, aim, and scope
Fenoxycarb is an insect growth regulator widely used to control a variety of pests. As a juvenile hormone analogue, it interacts with the natural hormones involved in insect development, inhibiting metamorphosis to the adult stage. Adverse effects of fenoxycarb on non-target organisms have been repeatedly observed and its rapid dissipation from water to the organic fraction of the sediment is known. The aim of this work was to investigate the impact of fenoxycarb on the development of sediment-dwelling larvae of the midge Chironomus riparius after exposure to spiked sediment. 相似文献34.
Summary Flowering and true seed production from different order inflorescences in potato (Solanum tuberosum L.) were evaluated in two experiments. The number of flowers per inflorescence, berry set, berry weight, number of seeds
per berry and seed weight generally decreased from primary inflorescences to tertiary inflorescences and inflorescences on
lateral stems. The possible relation with carbohydrate distribution is discussed. Quality of the seeds produced from the different
orders of inflorescences was a function of seed size; larger seeds showed better germination, emergence and seedling growth.
Late harvest of berries increased berry weight and number of seeds per berry from primary inflorescences. Application of additional
nitrogen during the flowering period did not affect flowering or differences between inflorescence positions in seed production,
but it significantly decreased the number of seeds per berry. The practical implications of these results for true seed production
are discussed. 相似文献
35.
Andrea Bannert Cornelia Mueller-Niggemann Kristina Kleineidam Livia Wissing Zhi-Hong Cao Lorenz Schwark Michael Schloter 《Biology and Fertility of Soils》2011,47(7):839-843
In the last years, archaea have been identified as key players in global N cycling, especially in nitrification. Ammonia-oxidizing
archaea (AOA) are postulated to belong to the new phylum Thaumarchaeota for which the lipid crenarchaeol should be specific.
The ratios between two independent markers for AOA, the ammonia monooxygenase gene and crenarchaeol have been studied in different
aerated soils, but so far not in flooded soils. This study investigated ammonia-oxidizing archaea in four paddy soils and
a tidal wetland. Ratios were significantly higher in the paddy soils compared to the tidal wetland and in general higher as
in upland soils, leading to the assumption that archaeal ammonia oxidizers different from crenarchaeol-containing Thaumarchaeota
may play an important role in paddy soils. 相似文献
36.
Artemisia vulgaris (mugwort) is a tall (1.0?C2.0 m) high biomass perennial herb which accumulates considerable amounts of metals on contaminated sites. An outdoor pot experiment was conducted on a sandy, slightly alkaline soil of moderate fertility to study the uptake of cadmium and the distribution of Cd in plant tissues of A. vulgaris. Cadmium was applied as CdCl2 (a total of 1 l solution of 0, 10, 50 and 100 mg Cd l?1) to 12-l pots with a height of 25 cm. HNO3- and water-extractable concentrations of Cd were correlated with the applied Cd at 2-cm soil depth, but were not correlated at 20-cm soil depth, suggesting that Cd was either not mobile in the soil or completely taken up by mugwort roots. The Cd concentrations in different organs of A. vulgaris and litter increased with increasing soil contamination. Leaf/soil concentration ratios (BCFs) up to 65.93?±?32.26 were observed. Translocation of Cd to the aboveground organs was very high. The leaf/root Cd concentration ratio (translocation factor) ranged from 2.07?±?0.56 to 2.37 ± 1.31; however, there was no correlation of translocation factors to Cd enrichment, indicating similar translocation upon different soil contamination levels. In summary, A. vulgaris is tolerant to the metal concentrations accumulated, has a high metal accumulating biomass and accumulates Cd up to about 70% in the aboveground parts. Both a high phytoextraction potential and a high value for phytostabilisation would recommend mugwort for phytoremediation. 相似文献
37.
Valeria Villanova Christian Galasso Giovanni Andrea Vitale Gerardo Della Sala Johan Engelbrektsson Niklas Strmberg Kashif Mohd Shaikh Mats X. Andersson Fortunato Palma Esposito Susanne Ekendahl Donatella De Pascale Cornelia Spetea 《Marine drugs》2022,20(7)
A local strain of Nannochloropsis granulata (Ng) has been reported as the most productive microalgal strain in terms of both biomass yield and lipid content when cultivated in photobioreactors that simulate the light and temperature conditions during the summer on the west coast of Sweden. To further increase the biomass and the biotechnological potential of this strain in these conditions, mixotrophic growth (i.e., the simultaneous use of photosynthesis and respiration) with glycerol as an external carbon source was investigated in this study and compared with phototrophic growth that made use of air enriched with 1–2% CO2. The addition of either glycerol or CO2-enriched air stimulated the growth of Ng and theproduction of high-value long-chain polyunsaturated fatty acids (EPA) as well as the carotenoid canthaxanthin. Bioassays in human prostate cell lines indicated the highest antitumoral activity for Ng extracts and fractions from mixotrophic conditions. Metabolomics detected betaine lipids specifically in the bioactive fractions, suggesting their involvement in the observed antitumoral effect. Genes related to autophagy were found to be upregulated by the most bioactive fraction, suggesting a possible therapeutic target against prostate cancer progression. Taken together, our results suggest that the local Ng strain can be cultivated mixotrophically in summer conditions on the west coast of Sweden for the production of high-value biomass containing antiproliferative compounds, carotenoids, and EPA. 相似文献
38.
Hematologic reference intervals for Rana sylvatica (Lithobates sylvaticus) and effect of infection with Frog Virus 3 (Ranavirus sp., Iridoviridae)
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40.
The aim of this study was to test the effect of heavy‐metal contamination (Cu, Zn) on the growth of Chlorella kessleri. Two soils (Chernozem and Podzoluvisol) were contaminated with several amounts of copper and zinc (100–3000 ppm), and the effects of the soil eluates on the growth of the alga were examined over several days. The soil eluates inhibited algal growth in dependence on metal concentration and soil properties. It was shown that this algal assay, which was first developed for aquatic samples, in principle seems to be suitable also in monitoring soil contamination. 相似文献