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251.
X Q Gao  L Bj?rk 《Fitoterapia》2000,71(1):19-24
To investigate the variations of active compounds between species, varieties and individuals of Valeriana cultivated under the same environmental condition, the contents of valerenic acid derivatives and valepotriates in rhizomes and roots of different plant material were analysed by a HPLC method. Different species or varieties of Valeriana yielded 11.65-0.15 mg/g of valerenic acid derivatives, and 1.81-0.03 mg/g of valepotriates. The variation between individuals of one commercial cultivar of V. officinalis ranged from 12.34 to 3.01 mg/g of valerenic acid derivatives, and 3.67-0.92 mg/g of valepotriates. Individuals from self-pollinated mother plants, normal or regenerated, showed a similar variation. The variation of micropropagated plants was much less than the seed propagated plants. The ratio of mean values between valerenic acid derivatives and valepotriates was similar in all groups (3 < ratio < 8) except one group of micropropagated plants (ratio > 20).  相似文献   
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Classification of thermally modified wood by FT-NIR spectroscopy and SIMCA   总被引:1,自引:0,他引:1  
Quality assessment of thermally modified wood has evolved as one of the major fields in the research on thermal modification of wood. This study investigates NIR spectroscopy in combination with the pattern recognition method of soft independent modeling of class analogies (SIMCA). Focus is put on identifying different treatment intensities of thermally modified samples of beech, ash, and Norway spruce. The results indicate that SIMCA classification based on NIR spectroscopy could be used for quality control of thermally modified wood. The method might be applicable for producers (pre-delivery checks) and customers (reception control). However, transfer from laboratory to industrial conditions needs further investigation.  相似文献   
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Eleven cows in late lactation were exposed to butyric acid for three weeks and were compared to five controls. Two intraruminal doses were daily applied, that is 1.0 g/kg B.W. of butyric acid to six animals and 1.0 g/kg B.W. of sodium butyrate to another five. Decline in milk yield was clinically recorded in response to butyric acid, while muscle tremor and diarrhoea resulted additionally from sodium butyrate. Behaviours of the clinico-chemical parameters of beta-OH-butyrate, glucose, free fatty acids, bilirubin, ASAT, gamma-GT, AP, and cholesterol were comparable to those in fattening bulls. Liver damage was not safely established. Some of the clinico-chemical alterations were more strongly pronounced after administration of sodium butyrate. One cow fell ill with ketosis under butyric acid load.  相似文献   
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After a 45-hour infusion of 15N-lysine and 15N-glycine resp. with pigs of 25 kg live weight, the infusion of the tracer was disrupted and a 3-day reduction phase was made part of the experiment. The N-metabolism parameters such as protein synthesis and decomposition quotas were calculated on the basis of the temporal development of 15N-amounts excreted in urine. The labelling and reduction phases were evaluated simultaneously. By means of including the total N-amount of the animal body the balance calculation becomes more stable. The possible influence of the tracer amino acid in connection with the 3-pool-model is discussed on the basis of the ascertained parameters.  相似文献   
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