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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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Atoms interacting with intense laser fields can emit electrons and photons of very high energies. An intuitive and quantitative explanation of these highly nonlinear processes can be found in terms of a generalization of classical Newtonian particle trajectories, the so-called quantum orbits. Very few quantum orbits are necessary to reproduce the experimental results. These orbits are clearly identified, thus opening the way for an efficient control as well as previously unknown applications of these processes.  相似文献   
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Bottom trawl fishing is a controversial activity. It yields about a quarter of the world's wild seafood, but also has impacts on the marine environment. Recent advances have quantified and improved understanding of large‐scale impacts of trawling on the seabed. However, such information needs to be coupled with distributions of benthic invertebrates (benthos) to assess whether these populations are being sustained under current trawling regimes. This study collated data from 13 diverse regions of the globe spanning four continents. Within each region, we combined trawl intensity distributions and predicted abundance distributions of benthos groups with impact and recovery parameters for taxonomic classes in a risk assessment model to estimate benthos status. The exposure of 220 predicted benthos‐group distributions to trawling intensity (as swept area ratio) ranged between 0% and 210% (mean = 37%) of abundance. However, benthos status, an indicator of the depleted abundance under chronic trawling pressure as a proportion of untrawled state, ranged between 0.86 and 1 (mean = 0.99), with 78% of benthos groups > 0.95. Mean benthos status was lowest in regions of Europe and Africa, and for taxonomic classes Bivalvia and Gastropoda. Our results demonstrate that while spatial overlap studies can help infer general patterns of potential risk, actual risks cannot be evaluated without using an assessment model that incorporates trawl impact and recovery metrics. These quantitative outputs are essential for sustainability assessments, and together with reference points and thresholds, can help managers ensure use of the marine environment is sustainable under the ecosystem approach to management.  相似文献   
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Decision-making consists of selecting an action from a set of available options. This results in an outcome that changes the state of the decision-maker. Therefore, decision-making is part of a homeostatic process. Individuals with psychiatric disorders show altered decision-making. They select options that are either non-optimal or nonhomeostatic. These dysfunctional patterns of decision-making in individuals with psychiatric disorders may fundamentally relate to problems with homeostatic regulation. These may manifest themselves in (i) how the length of time between decisions and their outcomes influences subsequent decision-making, (ii) how gain and loss feedback are integrated to determine the optimal decision, (iii) how individuals adapt their decision strategies to match the specific context, or (iv) how seemingly maladaptive responses result from an attempt to establish an unstable homeostatic balance.  相似文献   
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Objective To investigate wool organophosphorus concentrations resulting from a range of farm pesticide application methods.
Design Random sampling of wool for pesticide residues and on-farm interviews to determine associated treatments.
Procedure Tasmanian fleece wool lots were sampled at random and tested for organophosphorus residues. The grower was identified and the pesticide treatments applied to the sheep were ascertained by on-farm interview.
Results The residue concentrations showed a large variation that was not accounted for by differences in treatments by growers. Organophosphorus concentrations were proportional to the number of treatments applied, and inversely related to the time between pesticide application and the subsequent shearing, and were significantly influenced by the method of application. After allowing for the time of application, plunge dipping resulted in pesticide residue concentrations 2 to 2.5 times greater than shower dipping, using spray races or hand jetting, and the use of these methods caused larger residues than the use of jetting races.
Conclusions We recommend that plunge or shower dipping should not be used more than 7 weeks after shearing, nor at higher concentration than the standard dose rate used for lice control, whereas jetting may be satisfactory for up to 7 months after shearing, provided only one application is administered.  相似文献   
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