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排序方式: 共有285条查询结果,搜索用时 15 毫秒
61.
62.
Tolerance to Formalin by a Fluidized-Bed Biofilter and Rainbow Trout Oncorhynchus mykiss in a Recirculating Culture System 总被引:1,自引:0,他引:1
John M. Heinen Amy L. Weber Alicia C. Noble Joseph D. Morton 《Journal of the World Aquaculture Society》1995,26(1):65-71
Formalin tolerances of a fluidized-bed sand biofilter and rainbow trout Oncorhynchus mykiss were tested in a semi-closed freshwater recirculating culture system. Progressively higher formalin levels were tested until fish mortality (±1.9%) occurred. A 1-h exposure to 167 ppm formalin, followed by flushing, was safe for trout (no mortality) at 15.0 C but not at 16.5 C. A 110-ppm indefinite treatment (no flushing) was safe at 17.3 C, but 120 ppm at 17.3 C and 100 ppm at 17.8 C were not. Biofilter nitrification was not impaired by 1-h formdin treatments up to 167 ppm at 16.5 C, and not, usually, by indefinite treatments up to 120 ppm at 17.3 C. However, a find indefinite treatment of 70 ppm was followed by abnormally high nitrite levels for 9 d. Formaldehyde remained detectable in the system for 11 h during indefinite treatment at 120 ppm formalin. Tests on the system's Co2 stripper did not indicate that it removed formaldehyde. 相似文献
63.
Cancer regression and autoimmunity in patients after clonal repopulation with antitumor lymphocytes 总被引:1,自引:0,他引:1
Dudley ME Wunderlich JR Robbins PF Yang JC Hwu P Schwartzentruber DJ Topalian SL Sherry R Restifo NP Hubicki AM Robinson MR Raffeld M Duray P Seipp CA Rogers-Freezer L Morton KE Mavroukakis SA White DE Rosenberg SA 《Science (New York, N.Y.)》2002,298(5594):850-854
We report here the adoptive transfer, to patients with metastatic melanoma, of highly selected tumor-reactive T cells directed against overexpressed self-derived differentiation antigens after a nonmyeloablative conditioning regimen. This approach resulted in the persistent clonal repopulation of T cells in those cancer patients, with the transferred cells proliferating in vivo, displaying functional activity, and trafficking to tumor sites. This led to regression of the patients' metastatic melanoma as well as to the onset of autoimmune melanocyte destruction. This approach presents new possibilities for the treatment of patients with cancer as well as patients with human immunodeficiency virus-related acquired immunodeficiency syndrome and other infectious diseases. 相似文献
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Lois Wright Morton Elise Regen David M. Engle James R. Miller Ryan N. Harr 《Strength and Conditioning Journal》2010,63(6):645-654
Successful prairie restoration will depend in part on convincing private landowners with agricultural and recreational use goals to implement appropriate rangeland management practices, such as prescribed burning and cattle grazing, to control invasive species and encroachment of woody plants. However, landowners have been slow to adopt appropriate practices in the US Midwest. The purpose of this study was to explore attitudes and behaviors of private landowners toward prescribed burning and moderate stocking as rangeland management tools. A survey was mailed to 193 landowners (response rate 51%) in the Grand River Grasslands region of southern Iowa and northern Missouri. While 68% of landowners viewed grazing as a legitimate land management tool, only half of landowners thought of fire as a legitimate tool. Over 75% of respondents believed that the increase in eastern redcedar and other trees in grasslands was a problem, with 44% considering it a major problem. Although 84% of landowners said that they had taken action to control eastern redcedar, only 25% had participated in a prescribed burn. Income from agriculture and recreational goals were negatively and significantly correlated (-0.252, P = 0.035). While holding recreational goals constant in the analysis, landowners reporting income from agriculture goals as very or extremely important were negatively and significantly associated with reporting environment and grassland factors as very or extremely important. Adoption of prescribed burning by private landowners might be more widespread if proponents focus on the effectiveness of fire for controlling eastern redcedar, which is viewed as a problem by most landowners in the region. Intervention efforts must include landowners with different goals as part of the promotion and educational process. 相似文献
66.
Bekhit Ael-D Geesink GH Ilian MA Morton JD Sedcole R Bickerstaffe R 《Journal of agricultural and food chemistry》2003,51(20):6026-6035
There is controversy about the effect of storage time on metmyoglobin (MetMb) reducing activity in the sarcoplasmic fraction of meat and the role of this reducing activity in maintaining the color of red meat. The presence of metmyoglobin reducing activity in the myofibrillar fraction of muscle extracts was investigated as a possible reason for this controversy. NADH-dependent MetMb reducing activity was found in the particulate fraction of meat following sedimentation of a meat homogenate at 35 000g. There was 5.8 times more MetMb reducing activity in the particulate fraction compared with that of the sarcoplasmic (supernatant) fraction. The presence of metmyoglobin reducing activity in the myofibrils (MMRA), defined as the activity in the sediment after centrifugation of a meat homogenate at 2 000g, was confirmed. The myofibrillar fraction contained 63% of the total MetMb reducing activity available in the meat. The relationship between muscle MetMb reducing activities and meat color parameters was investigated in a beef patties system. The particulate MetMb reducing activity (PMRA) in beef patties was found to be a good indicator of the total metmyoglobin reducing activity in meat and was positively correlated with the color parameters of the patties, suggesting that PMRA may be associated with red meat color of meat patties. 相似文献
67.
68.
Forecasting fire season severity in South America using sea surface temperature anomalies 总被引:2,自引:0,他引:2
Chen Y Randerson JT Morton DC DeFries RS Collatz GJ Kasibhatla PS Giglio L Jin Y Marlier ME 《Science (New York, N.Y.)》2011,334(6057):787-791
Fires in South America cause forest degradation and contribute to carbon emissions associated with land use change. We investigated the relationship between year-to-year changes in fire activity in South America and sea surface temperatures. We found that the Oceanic Ni?o Index was correlated with interannual fire activity in the eastern Amazon, whereas the Atlantic Multidecadal Oscillation index was more closely linked with fires in the southern and southwestern Amazon. Combining these two climate indices, we developed an empirical model to forecast regional fire season severity with lead times of 3 to 5 months. Our approach may contribute to the development of an early warning system for anticipating the vulnerability of Amazon forests to fires, thus enabling more effective management with benefits for climate and air quality. 相似文献
69.
Davis JL Papich MG Morton AJ Gayle J Blikslager AT Campbell NB 《Journal of veterinary pharmacology and therapeutics》2007,30(1):43-48
The purpose of this study was to determine the pharmacokinetics of etodolac following oral and intravenous administration to six horses. Additionally, in vitro cyclooxygenase (COX) selectivity assays were performed using equine whole blood. Using a randomized two-way crossover design, horses were administered etodolac (20 mg/kg) orally or intravenously, with a minimum 3-week washout period. Plasma samples were collected after administration for analysis using high pressure liquid chromatography with ultraviolet detection. Following intravenous administration, etodolac had a mean plasma half-life (t(1/2)) of 2.67 h, volume of distribution (Vd) of 0.29 L/kg and clearance (Cl) of 234.87 mL/h kg. Following oral administration, the average maximum plasma concentration (Cmax)) was 32.57 mug/mL with a t(1/2) of 3.02 h. Bioavailability was approximately 77.02%. Results of in vitro COX selectivity assays showed that etodolac was only slightly selective for COX-2 with a COX-1/COX-2 selectivity ratio effective concentration (EC)50 of 4.32 and for EC80 of 4.77. This study showed that etodolac is well absorbed in the horse after oral administration, and may offer a useful alternative for anti-inflammatory treatment of various conditions in the horse. 相似文献
70.