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排序方式: 共有269条查询结果,搜索用时 15 毫秒
1.
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
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Alexander Valverde DVM DVSc DACVA Cornelia I. Gunkel Dr. med. vet. MRCVS 《Journal of Veterinary Emergency and Critical Care》2005,15(4):295-307
Objective: This review discusses the different analgesic drugs and routes of administration used in large animals for acute pain management. General guidelines and doses are given to assist in choosing techniques that provide effective analgesia. Etiology: Noxious stimuli are perceived, recognized, and localized by specialized sensory systems located at spinal and supraspinal levels. Diagnosis: Localizing the source of the noxious stimulus as well as understanding the behavioral aspects and physiological changes that result from such insult is important to adequately diagnose and treat pain. Pain assessment is far from being definite and objective; not only are there species differences, but also individual variation. In addition, the behavioral and physiological manifestations vary with the acute or chronic nature of pain. Therapy: Pain management should include (1) selecting drugs that better control the type of pain elicited by the insult; (2) selecting techniques of analgesic drug administration that act on pathways or anatomical locations where the nociceptive information is being processed or originating from; (3) combining analgesic drugs that act on different pain pathways; and (4) provide the best possible comfort for the animal. Prognosis: Providing pain relief improves the animal's well being and outcome; however, interpreting and diagnosing pain remains difficult. Continuing research in pain management will contribute to the evaluation of the pathophysiology of pain, pain assessment, and newer analgesic drugs and techniques. 相似文献
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Nöckler K Kutzer P Reif S Rosenberger N Draeger A Bahn P Göllner C Erlbeck C 《Berliner und Münchener tier?rztliche Wochenschrift》2003,116(9-10):368-372
Brucella (B.) canis was isolated from ejaculate of a 4-year old Korthals-Griffon male dog after occurrence of epididymitis and orchitis. Despite several trials of therapy with different antibiotics relapes occurred, with B. canis being isolated from ejaculate, blood and urine samples, respectively. Bacteriological examinations were added by serological testing over a period of about 1.5 years. During the study SAT serum titre steadily dropped from 1:200 to 1:50. By CFT, B. canis antibodies were detectable at the beginning with a titre of 1:320 and to the end of the study with titres between 1:80 and 1:160. 相似文献
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ULTRASONOGRAPHIC DETECTION OF ADRENAL GLAND TUMOR AND URETEROLITHIASIS IN A GUINEA PIG 总被引:1,自引:0,他引:1
Lorrie Gaschen DVM Cornelia Ketz Dr. med. vet. Johann Lang Dr. med. vet Urs Weber Dr. med. vet. L. Bacciarini Dr. med. vet. Ingrid Kohler med. vet. 《Veterinary radiology & ultrasound》1998,39(1):43-46
A 5-year-old guinea pig was presented to the University of Berne Small Animal Radiology Department for an ultrasound examination of the abdomen to confirm a suspected diagnosis of Cushing's syndrome. The patient had bilateral alopecia, was apathic and obese. Ultrasonographically, a tumor of the left adrenal gland, obstruction of the left ureter by an ureterolith, as well as hydronephrosis of the left kidney were detected. During surgery to relieve the ureteral obstruction the adrenal gland tumor was removed. The guinea pig died post-operatively due to blood loss. The left adrenal gland tumor was found histopathologically to be an adenoma and the right adrenal gland also had multiple small adenomas, but grossly appeared normal. The ureterolith was analyzed and found by x-ray diffraction to consist of calcium carbonate. 相似文献
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It has been argued that the wide-scale provision of artificial surface water in semi-arid savannas may result in homogenisation of foraging regimes, compromising biodiversity and ecosystem resilience. This is the first landscape-scale study investigating to what degree artificial waterholes and natural rivers influence the distribution of large herbivores, and hence foraging patterns, in the Kruger National Park, South Africa. This is explored by examining consistencies within and differences between distribution patterns of herbivore feeding groups on different geologies. Seven years of dry season aerial census data of thirteen large herbivores were analysed in a GIS. It was found that different herbivores exhibit different distribution patterns around rivers and waterholes. It was found that most grazer species were associated with artificial waterholes, whereas browsers and mixed feeders were indifferent to waterholes and were associated with the main rivers. This has important management implications for artificial water provision in the KNP and potentially for other semi-arid African savanna conservation areas. Man-made waterholes are therefore features in the landscape that can change the distribution of herbivores, even in a landscape where natural water is available, transforming patterns of landscape use. Furthermore, it was also found that the underlying geology interacts with water distribution in shaping herbivore distributions, with artificial waterholes and rivers acting as stronger nodes of herbivore activity on nutrient-rich basaltic soils than nutrient-poor granitic soils. The results from this paper may be useful for designing surface water policies and management plans for Kruger and other savanna reserves in Africa in order to maximise biodiversity conservation. 相似文献
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Marilyn Holly Carla A. Kirts Yvonne Everett Jan L. Flora David O. Hansen Cornelia Butler Flora John A. Hayward David Haenke Alessandro Bonanno 《Agriculture and Human Values》1988,5(4):57-78
Marilyn Holly is an Associate Professor of Philosophy at the University of Florida. Her special interests include political philosophy, ethics and ecology, Jungian thought, and Native American spirituality in its relation to the environment. She is currently at work on a monograph-length piece on the latter topic. She has taught an undergraduate course in ethics and ecology, and plans to do so again. The following essay emerged from her search for a suitable text for such a course. 相似文献
10.
Hanh Nguyen Hong Cornelia Rumpel Gérard Bardoux Toan Tran Duc 《Soil biology & biochemistry》2011,43(2):223-230
Earthworms are important regulators of soil structure and soil organic matter (SOM) dynamics; however, quantifying their influence on SOM cycling in tropical ecosystems remains little studied. Simulated rainfall was used to disrupt casts produced by Amynthas khami and their surrounding soil (control) into a range of small sized aggregates (50-250, 250-500, 500-2000 and 2000-5000 μm). To gain insight into how earthworms influence SOM biogeochemical composition in the aggregates, we carried out elemental and stable isotope analysis, and analytical pyrolysis (Py GC/MS). We also characterized their lignin component after oxidation with cupric oxide (CuO).The C content of smaller size fractions (<500 μm) in the control soil was higher than in the larger fractions. Our study therefore suggests that the aggregate hierarchy concept, which is used to understand soil aggregates and SOM dynamics in temperate soils, may not be applicable to the tropical Acrisol studied here. Earthworms modified SOM organization in soil aggregates. Although the isotope analyses were useful for highlighting SOM enrichment in the earthworm casts, aggregate fractions could not be classified according to particle size. Molecular analyses were necessary to indicate that SOM in all size fractions of casts consisted of relatively undecomposed material. Protection of the most labile SOM structures occurred in the smallest aggregate size fraction (50-250 μm). Py GC/MS showed that earthworm casts and control aggregates <2000 μm could be clearly distinguished according to the molecular properties of their SOM. Aggregates larger than 2000 μm, however, were most probably composed of all fractions and were not different. As a consequence, our results indicate that studies to determine the impact of earthworms on SOM turnover in soil are spatially dependant on the scale of observation. 相似文献