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991.
Online search data provide us with a new perspective for quantifying public concern about animal diseases, which can be regarded as a major external shock to price fluctuations. We propose a modeling framework for pork price forecasting that incorporates online search data with support vector regression model. This novel framework involves three main steps: that is, formulation of the animal diseases composite indexes (ADCIs) based on online search data; forecast with the original ADCIs; and forecast improvement with the decomposed ADCIs. Considering that there are some noises within the online search data, four decomposition techniques are introduced: that is, wavelet decomposition, empirical mode decomposition, ensemble empirical mode decomposition, and singular spectrum analysis. The experimental study confirms the superiority of the proposed framework, which improves both the level and directional prediction accuracy. With the SSA method, the noise within the online search data can be removed and the performance of the optimal model is further enhanced. Owing to the long-term effect of diseases outbreak on price volatility, these improvements are more prominent in the mid- and long-term forecast horizons. 相似文献
992.
Zusammenfassung Quantitative Analysen des-mercaptobrenztraubensäure-spaltenden Enzyms zeigen, dass Zellen, die sich in aktivem mitotischem Prozess befinden (bzw. Krebszellen und Gewebekulturen), dieses Enzym in viel geringerem Masse enthalten als « normale » Zellen. Da dieses Enzym in dem anaeroben Stoffwechsel von Zystein eine wichtige Rolle spielt, lässt sich vermuten, dass sich der Zysteinstoffwechsel der Tumorzelle quantitativ von dem der Normalzelle unterscheidet.
Supported by U.S. Public Health Grants H-2897, C-3211 and by a grant of the American Cancer Society (70-4612-24). 相似文献
Supported by U.S. Public Health Grants H-2897, C-3211 and by a grant of the American Cancer Society (70-4612-24). 相似文献
993.
994.
Summary Viscero-somatic reflexes have been studied by recording monosynaptic reflexes following distension of the urinary bladder in intact, decerebrate and spinal animals. It was observed that the viscero-somatic responses following bladder distension are inhibitory in nature and this inhibition was highest in decerebrates and least in spinal animals. The site of viscero-somatic interaction probably lies in the bulbar area (supraspinal) and spinal cord.Acknowledgment. The work was carried out with the financial assistance of the Indian Council of Medical Research, Govt of India. We are thankful to A. T. Pradhan, Abott Laboratories (India) Pvt. Ltd. for a generous supply of Nembutal. 相似文献
995.
A. W. K. Chan Donna L. Schanley Florence W. Leong 《Cellular and molecular life sciences : CMLS》1980,36(7):859-860
Summary The effects of chronic administration of 2 types of liquid diets on brain thiamine pyrophosphate (TPP) levels have been investigated. With the Lieber-DeCarli diet, rats in the control group had significantly lower TPP levels compared with those of the ethanol group. The Nutrament diet used in mice was apparently adequate in the thiamine supply.Acknowledgment. The authors are thankful to Dr Hebe Greizerstein for her review and comments on this mansucript. 相似文献
996.
997.
Ten-day treatment with nicotine (5, 25 or 50 micrograms/ml drinking water) dose-dependently intensified gastric ulceration induced by cold-restraint, and emptying rate. Stomach contractions produced by graded doses of bethanechol i.v. were elevated further by nicotine treatment. It is suggested that chronic nicotine administration produces hypersensitivity of the gastric muscarinic receptors; stomach hypermotility contributes to the ulcer-worsening action of the alkaloid. 相似文献
998.
G. E. Risinger K. Karimian St. Jungk J. B. Simpson 《Cellular and molecular life sciences : CMLS》1978,34(9):1121-1122
Summary New biosynthetic pathways for the irregular terpenes, artemisia ketone and bakuchiol, are proposed. It is suggested that 2-(1-hydroxy-3-methylbutyl)thiamine and 2-(1-hydroxy-2-phenylethyl) thiamine are key intermediates in the biosyntheses of artemisia ketone and bakuchiol, respectively. 相似文献
999.
1000.