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Despite the wide availability of liquid herbal extracts using mixtures of alcohol, glycerin, and water, or glycerin and water as solvents, no data on the chemical composition of such extracts is readily available. In this study, the amount and the stability of the major saponins in Panax quinquefolius root extracts, made either with 50% (v/v) aqueous ethanol, a mixture (v/v/v) of 20% ethanol, 40% glycerin, and 40% water, or with 65% (v/v) aqueous glycerin, were evaluated by HPLC-UV analysis. The amount of total saponins was highest in the 50% aqueous ethanol extract (61.7 +/- 0.1 mg/g dry root), although similar to the ethanol-glycerin-water extract (59.4 +/- 0.5 mg/g dry root). Saponins were significantly lower in the 65% aqueous glycerin extract (51.5 +/- 0.2 mg/g dry root). Interestingly, the amounts of individual saponins were quite variable depending on the solvent. This is in part due to enzymatic cleavage of ginsenosides in the glycerin containing extracts during the maceration process. Storage of the extracts at 25 degrees C over the period of a year led to a 13-15% loss of saponins with all three types of extractions.  相似文献   
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Two Friesian cows were used to attempt to produce colostrum containing a high concentration of clostridial antibodies which could be fed to newborn lambs in order to passively transfer immunity to diseases caused by clostridia. One cow was given a commercial multicomponent clostridial sheep vaccine in two successive pregnancies and the second cow in one pregnancy. The first cow produced a low concentration of epsilon antitoxin (Clostridium perfringens, type D) in its blood and colostrum after the first course of three injections of vaccine. A higher concentration was produced by cow 2 after a course of six injections and by cow 1 after a further course of four injections in its next pregnancy. Two hundred ml of colostrum from cow 1 (after the second course of vaccine) was given to 12 newborn colostrum-deprived lambs. All showed a high concentration of antitoxin 48 hours later. The lambs were actively immunised by injections of the same clostridial vaccine at three and nine weeks or six and 12 weeks old and all produced sufficient antitoxin to protect up to slaughter at 24 weeks. It is concluded that colostrum from cows vaccinated with sheep clostridial antigens can be fed to protect lambs passively.  相似文献   
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Sir:- Benzimidazole (Bz) resistant Nematodirus spathiger were first recorded in New Zealand in 1983.(2)  相似文献   
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Evidence is presented that corn (maize) and sorghum starch granules have channels that connect a central cavity to the external environment. A mutant sorghum starch with numerous, large surface pores was treated with a methanolic solution of merbromin and sectioned. Light, fluorescence, and compositional backscattering electron microscopy revealed channels connecting an internal cavity to the external surface in most granules. Cavities and channels could also be seen in whole corn and sorghum starch granules treated with merbromin in methanol and viewed by fluorescence microscopy. Treatment of sorghum starch granules with an aqueous solution of merbromin revealed that the molecule penetrated the granule matrix under even slightly swelling conditions. Light microscopy showed cavities in unstained, whole, dry corn and sorghum starch granules mounted in immersion oil.  相似文献   
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