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排序方式: 共有240条查询结果,搜索用时 31 毫秒
51.
Grubb TL Högman M Edner A Frendin JH Heinonen E Malavasi LM Frostell CG Ryden A Alving K Nyman GC 《American journal of veterinary research》2008,69(3):423-430
OBJECTIVE: To assess physiologic responses and plasma endothelin (ET)-1 concentrations associated with abrupt cessation of nitric oxide (NO) inhalation in isoflurane-anesthetized horses. ANIMALS: 6 healthy adult Standardbreds. PROCEDURES: Horses were anesthetized with isoflurane in oxygen and placed in dorsal recumbency. Nitric oxide was pulsed into the respiratory tract for 2.5 hours, and then administration was abruptly discontinued. Just prior to commencement and at cessation of NO administration, and at intervals during a 30-minute period following cessation of NO inhalation, several variables including PaO(2), mean pulmonary artery pressure, venous admixture or pulmonary shunt fraction (Qs/Qt), and plasma ET-1 concentration were recorded or calculated. RESULTS: After cessation of NO inhalation, PaO(2) decreased slowly but significantly (172.7 +/- 29.8 mm Hg to 84.6 +/- 10.9 mm Hg) and Qs/Qt increased slowly but significantly (25 +/- 2% to 40 +/- 3%) over a 30-minute period. Mean pulmonary artery pressure increased slightly (14.0 +/- 1.3 mm Hg to 16.8 +/- 1 mm Hg) over the same time period. No change in serum ET-1 concentration was detected, and other variables did not change or underwent minor changes. CONCLUSIONS AND CLINICAL RELEVANCE: The improvement in arterial oxygenation during pulsed inhalation of NO to healthy isoflurane-anesthetized horses decreased only gradually during a 30-minute period following cessation of NO inhalation, and serum ET-1 concentration was not affected. Because a rapid rebound response did not develop, inhalation of NO might be clinically useful in the treatment of hypoxemia in healthy isoflurane-anesthetized horses. 相似文献
52.
Most government policies and community perception of the irrigation sector promotes the conversion from gravity-fed to pressurised irrigation methods as a way of reducing water consumption by the irrigation sector. However, optimising for one aspect of a system can have unintended resource and environmental consequences e.g. an increase in energy consumption patterns of irrigated crops. Two Australian irrigation areas were studied: a surface-water supplied region in New South Wales; and a groundwater dependent region in South Australia. The water and energy budgets for crop production from land preparation to harvest were quantified on several farms. Converting from flood to pressurised systems resulted in a reduction in water application of between 10% and 66%. However, in the surface-water supplied region, it also resulted in energy consumption being increased by up to 163%. In the groundwater dependent region, energy consumption was reduced by 12% to 44%. There is potential to reduce energy consumption due to increased water use efficiency, resulting in less water being pumped due to efficiency gains. Therefore, to optimise energy and water use, it is recommended that pressurised irrigation systems be used in areas requiring pressurised extraction of groundwater, while efficient gravity based irrigation methods, coupled with good management practices, be promoted in surface-water supplied areas. 相似文献
53.
Milaja Nyknen Marie Louis Eileen Dillane Eric Alfonsi Simon Berrow Joanne O'Brien Andrew Brownlow Pablo Covelo Willy Dabin Rob Deaville Renaud de Stephanis Franois Gally Pauline Gauffier Simon N. Ingram Tamara Lucas Luca Mirimin Rod Penrose Emer Rogan Mnica A. Silva Benoit Simon‐Bouhet Oscar E. Gaggiotti 《水产资源保护:海洋与淡水生态系统》2019,29(Z1):197-211
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Inflammation in pulp tissue is caused by caries bacteria. Most bacteria found are Lactobacillus acidophilus. Propolis is a sticky resin material that is derived from the bees and the surrounding plants, which are reported to have several biological effects including anti-bacterial and anti-inflammatory. This study will prove the effectiveness of propolis against proinflammatory cytokines on odontoblast-like cells in human dental pulp. This study was performed on cultured odontoblast-like cells in pulp. Cell culture was derived from the pulp tissue of human M3 teeth that had been extracted. Odontoblast pulp culture was divided in three groups: group one, cultured cells with propolis; group two, cultured cells induced with inactive Lactobacillus acidophilus; group three, cultured cells induced with inactive Lactobacillus acidophilus and exposed to 3 μg/mL propolis. A measurement of TNF-α and TGF-β1 expression was done using the immunocytochemical technique to determine the effectiveness of propolis extracts from East Java Indonesia against proinfalmmatory cytokines. Data were analyzed using the analysis of variance (ANOVA) test (P = 0.05). Propolis extract can inhibit the expression of TNF-α and increase the expression of TGF-β1 on odontoblast-like cell in human dental pulp. Anti-inflammatory effects of East Java propolis extract are associated with cytokine modulation. 相似文献
57.
Plant cuticular lipid export requires an ABC transporter 总被引:1,自引:0,他引:1
Pighin JA Zheng H Balakshin LJ Goodman IP Western TL Jetter R Kunst L Samuels AL 《Science (New York, N.Y.)》2004,306(5696):702-704
A waxy protective cuticle coats all primary aerial plant tissues. Its synthesis requires extensive export of lipids from epidermal cells to the plant surface. Arabidopsis cer5 mutants had reduced stem cuticular wax loads and accumulated sheetlike inclusions in the cytoplasm of wax-secreting cells. These inclusions represented abnormal deposits of cuticular wax and resembled inclusions found in a human disorder caused by a defective peroxisomal adenosine triphosphate binding cassette (ABC) transporter. We found that the CER5 gene encodes an ABC transporter localized in the plasma membrane of epidermal cells and conclude that it is required for wax export to the cuticle. 相似文献
58.
Loftus BJ Fung E Roncaglia P Rowley D Amedeo P Bruno D Vamathevan J Miranda M Anderson IJ Fraser JA Allen JE Bosdet IE Brent MR Chiu R Doering TL Donlin MJ D'Souza CA Fox DS Grinberg V Fu J Fukushima M Haas BJ Huang JC Janbon G Jones SJ Koo HL Krzywinski MI Kwon-Chung JK Lengeler KB Maiti R Marra MA Marra RE Mathewson CA Mitchell TG Pertea M Riggs FR Salzberg SL Schein JE Shvartsbeyn A Shin H Shumway M Specht CA Suh BB Tenney A Utterback TR Wickes BL Wortman JR Wye NH Kronstad JW Lodge JK 《Science (New York, N.Y.)》2005,307(5713):1321-1324
59.
Sofie E. De Meyer Koenraad Van Hoorde Bram Vekeman Tamara Braeckman Anne Willems 《Soil biology & biochemistry》2011,43(12):2384-2396
We investigated the diversity of rhizobia isolated from different indigenous legumes in Flanders (Belgium). A total of 3810 bacterial strains were analysed originating from 43 plant species. Based on rep-PCR clustering, 16S rRNA gene and recA gene sequence analysis, these isolates belonged to Bradyrhizobium, Ensifer (Sinorhizobium), Mesorhizobium and Rhizobium. Of the genera encountered, Rhizobium was the most abundant (62%) and especially the species Rhizobiumleguminosarum, followed by Ensifer (19%), Bradyrhizobium (14%) and finally Mesorhizobium (5%). For two rep-clusters only low similarity values with other genera were found for both the 16S rRNA and recA genes, suggesting that these may represent a new genus with close relationship to Rhodopseudomonas and Bradyrhizobium. Primers for the symbiotic genes nodC and nifH were optimized and a phylogenetic sequence analysis revealed the presence of different symbiovars including genistearum, glycinearum, loti, meliloti, officinalis, trifolii and viciae. Moreover, three new nodC types were assigned to strains originating from Ononis, Robinia and Wisteria, respectively. Discriminant and MANOVA analysis confirmed the correlation of symbiosis genes with certain bacterial genera and less with the host plant. Multiple symbiovars can be present within the same host plant, suggesting the promiscuity of these plants. Moreover, the ecoregion did not contribute to the separation of the bacterial endosymbionts. Our results reveal a large diversity of rhizobia associated with indigenous legumes in Flanders. Most of the legumes harboured more than one rhizobial endosymbiont in their root nodules indicating the importance of including sufficient isolates per plant in diversity studies. 相似文献