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中草药提取技术的概述   总被引:1,自引:0,他引:1  
简述了中草药的系列提取方法及其应用。其中对101-澄清剂提取法作了较详细的介绍,因为该法是目前应用最广、效果最好、简易可行、经济实用的可替代醇沉法的一种新型提取方法。  相似文献   
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The extraction of coral reef organisms for the aquarium and curio trade is reported to be contributing to coral reef degradation. The total international trade and associated impacts are unknown, because data are collected only for organisms listed on Appendix II of CITES, which include stony corals, antipatharians and giant clams. CITES data indicate that trade in live stony coral and reef substrate (live rock) increased by 15–30% each year during the 1990s, with most exports since 1992 from Indonesia and Fiji. Overall, 19% of all stony coral traded (by item) from 1985 to 1997 was live; 71kern-1pt% of this was traded between 1993 and 1997 (52% of total trade). Although tracking trade using information from the CITES Trade Database provides limited information (e.g., coral is reported to genus, and volume is reported by item or weight), the CITES mechanism promotes the development of strategies to protect resources. In response to CITES requirements, Indonesia developed a management plan for sustainable harvest of corals, but not for non-CITES listed species such as soft corals and fishes. Trade in hard and soft coral provides revenue for developing countries; however, in order to be of lasting value the industry must be developed with a conservation ethic. This requires support for international programs such as CITES, management plans for sustainable harvest, and improved enforcement.  相似文献   
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We report major element composition ratios for regions of the asteroid 433 Eros imaged during two solar flares and quiet sun conditions during the period of May to July 2000. Low aluminum abundances for all regions argue against global differentiation of Eros. Magnesium/silicon, aluminum/silicon, calcium/silicon, and iron/silicon ratios are best interpreted as a relatively primitive, chondritic composition. Marked depletions in sulfur and possible aluminum and calcium depletions, relative to ordinary chondrites, may represent signatures of limited partial melting or impact volatilization.  相似文献   
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Equipment and handling methods for the preparation of soil mesocosms were developed. The mesocosms were used to investigate the interrelationships between mesofauna and microflora in a coniferous forest soil. Soil monoliths were taken from the ground, defaunated by deep-freezing, wrapped in nets to control reimmigration of different faunal size-classes, and replanted in the field for 8 months. in a practical test the technique described here proved to be an inexpensive field method for producing a replicated series of mesocosm in a short time. Deep-freezing is appropriate for defaunating soil monoliths. The fine nets effectively exluded meso-and macrofauna. No significant differences were found in the abundance of Enchytraeids and Collembola between recolonized mesocosms and the undisturbed control at the end of the study period. In contrast, oribatid mite abundace was still greatly reduced in the recolonized esocosms. Dominance structure and species composition of the more dominant oribatid species in the different treatments were apparently similar. To compensate for the low colonization ability of oribatids, a reintroduction of selected animal size-classes to defaunated monoliths is recommended.  相似文献   
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In 2010, we observed again an increase in the number of declarations reported to the vigilance system for veterinary medicinal products up to a total of 160. The species and drug classes reported remained the same as in previous years: the majority of adverse drug reactions (ADRs) concerned either dogs or cats and the most frequently involved drugs were either antiparasitic products or antiinfectives. Adverse reactions following reconversions and 8 cases of suspected allergic reactions following the use of amoxicillin-clavulanic acid combinations in dogs were reported. Additional enquiries were processed by the Swiss Toxicological Information Centre and transmitted to Swiss medic. 11 of these reported accidental ingestions of flavoured tablets in overdose by dogs and some cats. The vaccino vigilance program received 179 declarations following immunization against blue tongue disease as well as 82 declarations following the application of other vaccines. The vigilance system increases the chance to identify rare reactions or interactions and thereby contributes to the security of veterinary medicinal products.  相似文献   
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Background: Bluetongue virus serotype 8 (BTV‐8) has caused disease in domestic ruminants in several countries of northern Europe since 2006. In 2008 a mass‐vaccination program was launched in most affected countries using whole virus inactivated vaccines. Objective: To evaluate 2 inactivated vaccines (Bovilis BTV 8; BTVPUR AlSap8) for immunogenicity and safety against BTV‐8 in South American camelids (SAC) in a field trial. Animals: Forty‐two SAC (25 Alpacas, 17 Llamas) aged between 1 and 16 years. Methods: The animals were vaccinated twice at intervals of 21 days. They were observed clinically for adverse local, systemic, or both reactions throughout the trial. Blood samples collected on days 0, 14, 21, 43, and 156 after vaccination were tested for the presence of BTV‐8 virus by real time‐polymerase chain reaction and of specific antibodies by competitive ELISA and a serum neutralization test. Results: All vaccinated animals developed antibodies to BTV‐8 after the 2nd administration of the vaccine. No adverse effects were observed except for moderate local swellings at the injection site, which disappeared within 21 days. Slightly increased body temperatures were only observed in the first 2 days after vaccination. The BTV was not detected in any of the samples analyzed. Conclusions and Clinical Importance: The administration of the 2 inactivated commercial vaccines was safe and induced seroconversion against BTV‐8 in all vaccinated animals. The results of this study suggest that 2 doses injected 3 weeks apart is a suitable vaccination regimen for SAC.  相似文献   
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The American beekeeping industry continually experiences colony mortality with annual losses as high as 43%. A leading cause of this is the exotic, ectoparasitic mite, Varroa destructor Anderson & Trueman (Mesostigmata: Varroidae). Integrated Pest Management (IPM) options are used to keep mite populations from reaching lethal levels, however, due to resistance and/or the lack of suitable treatment options, novel controls for reducing mites are warranted. Oxalic acid for controlling V. destructor has become a popular treatment regimen among commercial and backyard beekeepers. Applying vaporized oxalic acid inside a honey bee hive is a legal application method in the U.S., and results in the death of exposed mites. However, if mites are in the reproductive stage and therefore under the protective wax capping, oxalic acid is ineffective. One popular method of applying oxalic is vaporizing multiple times over several weeks to try and circumvent the problem of mites hiding in brood cells. By comparing against control colonies, we tested oxalic acid vaporization in colonies treated with seven applications separated by 5 d (35 d total). We tested in apiaries in Georgia and Alabama during 2019 and 2020, totaling 99 colonies. We found that adult honey bees Linnaeus (Hymenoptera: Apidae), and developing brood experienced no adverse impacts from the oxalic vaporization regime. However, we did not find evidence that frequent periodic application of oxalic during brood-rearing periods is capable of bringing V. destructor populations below treatment thresholds.  相似文献   
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