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排序方式: 共有5162条查询结果,搜索用时 62 毫秒
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Marjan M. Tajrishi Jonghyun Shin Michal Hetman Ashok Kumar 《The Journal of biological chemistry》2014,289(29):19985-19999
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M. Peña y Lillo R. Pérez-Correa E. Latrille M. Fernández G. Acuña E. Agosin 《Bioprocess and biosystems engineering》2000,22(4):291-297
Successful scaling up of Solid Substrate Cultivation (SSC) bioreactors has been hampered by the lack of reliable models that describe such processes satisfactorily. Even though experimental data may be available for model development, data analysis is hindered by system heterogeneity and noisy measurements. This work presents a data processing procedure for periodically agitated SSC fixed bed reactors. The procedure considers several steps. First, all measurements were pre-processed on-line during the cultivation using a low pass fourth order Butterworth digital filter. Then, using this pre-processed data, the average bed temperature, evaporation rate, removed heat, and CO2 production rate were computed off-line. The variables used to compute the evaporation rate and the removed heat were smoothed off-line with a peak shaving algorithm and a non-delay inducing forward/backward moving average scheme. Variables associated with biomass growth (CO2 and metabolic heat) are known to evolve slowly. Hence, these were reprocessed with a smoothing procedure in order to diminish the effects of bioreactor heterogeneity. Here, moving average smoothing was applied using a larger window than for other variables, and determined empirically in order to smooth the pre-processed data and extract its real trend. The whole procedure was assessed with data from a 200 kg capacity SSC bioreactor in the cultivation of a filamentous fungus (Gibberella fujikuroi) on wheat bran. 相似文献
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Manuel Algara Meritxell Arenas Dolores De las Peñas Eloisa Bayo Julia Muñoz José Antonio Carceller Juan Salinas Ferran Moreno Francisco Martínez Ezequiel González Ángel Montero 《Reports of Practical Oncology and Radiotherapy》2012,17(3):122-128
AimTo evaluate the resources and techniques used in the irradiation of patients with breast cancer after lumpectomy or mastectomy and the status of implementation of new techniques and therapeutic schedules in our country.BackgroundThe demand for cancer care has increased among the Spanish population, as long as cancer treatment innovations have proliferated. Radiation therapy in breast cancer has evolved exponentially in recent years with the implementation of three-dimensional conformal radiotherapy, intensity modulated radiotherapy, image guided radiotherapy and hypofractionation.Material and MethodsAn original survey questionnaire was sent to institutions participating in the SEOR-Mama group (GEORM). In total, the standards of practice in 969 patients with breast cancer after surgery were evaluated.ResultsThe response rate was 70% (28/40 centers). In 98.5% of cases 3D conformal treatment was used. All the institutions employed CT-based planning treatment. Boost was performed in 56.4% of patients: electrons in 59.8%, photons in 23.7% and HDR brachytherapy in 8.8%. Fractionation was standard in 93.1% of patients. Supine position was the most frequent. Only 3 centers used prone position. The common organs of risk delimited were: homolateral lung (80.8%) and heart (80.8%). In 84% histograms were used. An 80.8% of the centers used isocentric technique. In 62.5% asymmetric fields were employed. CTV was delimited in 46.2%, PTV in 65% and both in 38.5%. A 65% of the centers checked with portal films. IMRT and hypofractionation were used in 1% and in 5.5% respectively.ConclusionIn most of centers, 3D conformal treatment and CT-based planning treatment were used. IMRT and hypofractionation are currently poorly implemented in Spain. 相似文献
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l-Prolyl-l-leucyl-glycinamide is rapidly hydrolyzed by hypothalamic, hypophyseal and cortical homogenates from male or female rats. The peptidase activity is higher in the pituitary followed in decreasing order by the hypothalamus and the cerebral cortex. It is mostly localized in the supernatant fraction of a 100,000 g centrifugation and is inhibited by bacitracin.Tissues from female rats are half as active as those from male rats and show variations during the estrous cycle, with very low PLG metabolism at diestrus 1 in pituitary and hypothalamus. In contrast, the cerebral cortex at proestrus and estrus has significant lower hydrolyzing activity than at diestrus. No change of the peptidase activity is observed in tissues from ovariectomized animals after treatment with estrogen or progesterone.The results obtained suggest the existence of a correlation between peptidasic activity and melanotropin secretion. 相似文献
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Brains of young (newly emerged) adult female locusts (Locusta migratoria migratorioides) and of mature (> 9 days old) locusts contain an extractable allatotropic factor, soluble in 100% methanol and in distilled water. This factor stimulates juvenile hormone III (JH III) synthesis and release from corpora allata (CA) that have been excised from donor locusts and then incubated with (radiolabeled methyl)-methionine in vitro in its presence. In addition to JH III, which is the major product synthesized by the CA, other hexanesoluble, radiolabeled compounds–-more polar than JH III–-are also released when CA are incubated in vitro. The activation of CA by the allatotropic factor is rapid and quickly declines when the factor is removed from the medium. Corpora allata excised from young females are marginally active and can be activated by brain allatotropic factor to less of an extent than CA of mature locusts. The content of allatotropic factor in brains of mature locusts is higher than that ascertained in brains of young females. Allatotropic factor is also present in the corpora cardiaca. 相似文献
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C.S. Fagnant-Sperati Y. Ren N.A. Zhou E. Komen B. Mwangi J. Hassan A. Chepkurui R. Nzunza J. Nyangao W.B. van Zyl M. Wolfaardt P.N. Matsapola F.B. Ngwana S. Jeffries-Miles A. Coulliette-Salmond S. Peñaranda E. Vega J.H. Shirai A.L. Kossik N.K. Beck D.S. Boyle C.C. Burns M.B. Taylor P. Borus J.S. Meschke 《Journal of applied microbiology》2021,130(3):971-981