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1.
徐明霞 《饲料研究》2021,44(4):147-149
青蒿素是一种倍半萜内酯类化合物,其特殊的过氧基团结构使其具有抗疟疾、抗菌、抗炎、抗氧化、抗寄生虫、免疫调节、缓解热应激、促进生长等作用.青蒿素及其衍生物应用于动物生产中可以替代抗生素,具有广阔的应用前景.文章对青蒿素及其衍生物的生理功能、主要提取方式及在动物生产中的应用进行论述.  相似文献   
2.
为了探究蓟马取食对苜蓿(Medicago sativa L.)氨基酸组成及含量的影响,本研究以'草原2号'(Medicago varia Martin.'Caoyuan No.2')感蓟马品种和'草原4号'(Medicago sativa L.'Caoyuan No.4')抗蓟马品种为材料,分别进行牛角花齿蓟马(Odo...  相似文献   
3.
为了探讨人参皂苷及其衍生物抗马立克氏病病毒的作用机制.采用马立克氏病毒感染的雏鸡作为模型,人参皂苷及其衍生物口服给药途径,动态观察不同时间段,试验鸡的器官病理变化和脾脏、法氏囊的组织超微结构改变.结果发现人参皂苷及其衍生物组的器官病变程度明显低于病毒对照组,法氏囊和脾脏的超微结构病变轻于病毒对照组,说明人参皂苷及其衍生物在体内可以通过保护机体免疫器官来发挥抗病毒作用.  相似文献   
4.
ObjectiveTo evaluate the effects of incremental doses of acepromazine on hemodynamics in isoflurane-anesthetized dogs.Study designProspective, experimental study.AnimalsHealthy, adult, mixed-breed dogs (two male and four female) weighing 16.8 ± 5.1 kg (mean ± standard deviation).MethodsDogs were anesthetized with propofol (7 mg kg–1) intravenously (IV) and isoflurane. Thermodilution and arterial catheters were placed for hemodynamic monitoring and arterial blood sampling for blood gas analysis. Baseline measurements were performed with stable expired concentration of isoflurane (Fe′Iso) at 1.8%. Each dog was then administered four incremental acepromazine injections (10, 15, 25 and 50 μg kg–1) IV, and measurements were repeated 20 minutes after each acepromazine injection with Fe′Iso decreased to 1.2%. The four acepromazine injections resulted in cumulative doses of 10, 25, 50 and 100 μg kg–1 (time points ACP10, ACP25, ACP50 and ACP100, respectively).ResultsCompared with baseline, cardiac index (CI) increased significantly by 34%, whereas systemic vascular resistance index (SVRI) decreased by 25% at ACP50 and ACP100. Arterial oxygen content (CaO2) was significantly lower than baseline after all acepromazine injections (maximum decreases of 11%) and was lower at ACP50 and ACP100 than at ACP10. No significant change was found in heart rate, stroke index, oxygen delivery index and systolic, mean and diastolic blood pressures. Hypotension (mean arterial pressure < 60 mmHg) was observed in one dog at baseline, ACP10, ACP25 and ACP100, and in two dogs at ACP50.Conclusions and clinical relevanceCompared with isoflurane alone, anesthesia with acepromazine–isoflurane resulted in increased CI and decreased SVRI and CaO2 values. These effects were dose-related, being more pronounced at ACP50 and ACP100. Under the conditions of this study, acepromazine administration did not change blood pressure.  相似文献   
5.
Vertebrata lanosa is a red alga that can commonly be found along the shores of Europe and North America. Its composition of bromophenols has been studied intensely. The aim of the current study was therefore to further investigate the phytochemistry of this alga, focusing more on the polar components. In total, 23 substances were isolated, including lanosol-4,7-disulfate (4) and the new compounds 3,5-dibromotyrosine (12), 3-bromo-5-sulfodihydroxyphenylalanine (13), 3-bromo-6-lanosyl dihydroxyphenylalanine (14), 3-(6′-lanosyl lanosyl) tyrosine (15) and 5-sulfovertebratol (16). In addition, 4-sulfo-7-dimethylsulfonium lanosol (7) was identified. While, in general, the dimethylsulfonium moiety is widespread in algae, its appearance in bromophenol is unique. Moreover, the major glycerogalactolipids, including the new ((5Z,8Z,11Z,14Z,17Z)-eicosapentaenoic acid 3′-[(6′’-O-α-galactopyranosyl-β-D-galactopyranosyl)]-1-glycerol ester (23), and mycosporine-like amino acids, porphyra-334 (17), aplysiapalythine A (18) and palythine (19), were identified.  相似文献   
6.
Wu XD  Cheng JT  He J  Zhang XJ  Dong LB  Gong X  Song LD  Zheng YT  Peng LY  Zhao QS 《Fitoterapia》2012,83(6):1068-1071
A new benzophenone C-glycoside, malaferin A (1), and two new epicatechin derivatives, malaferin B (2) and malaferin C (3), together with five known compounds were isolated from Malania oleifera. In addition, (-)-epicatechin-3-O-benzoate (6) was isolated for the first time from a natural resource. Structures of 1-3 were determined on the basis of their spectroscopic methods, including 1D and 2D NMR techniques. All of the compounds were evaluated for anti-HIV activities.  相似文献   
7.
以没食子酸为原料, 通过甲基化、还原、溴代、Arbuzov重排、Wittig-Horner反应、O - 异戊烯基或O - 法尼烯基化等反应步骤,以总收率30%~35%合成了6种未见文献报道的新型的白藜芦醇类衍生物1a,1b,2a~2d. 所合成的化合物已通过MS,1HNMR和IR等波谱方法进行了结构确证. 该合成方法具有反应条件温和、后处理方便、产率较高和立体选择性强的优点.  相似文献   
8.
9.
壳聚糖及其衍生物在食品工业中的应用   总被引:1,自引:0,他引:1  
综述了壳聚糖及其衍生物的理化性质以及在食品工业中的应用,这些应用包括作为保健食品、食品添加剂、涂膜保鲜剂、水处理剂及作为固定化酶的载体,并且简要介绍了这些应用的机理。  相似文献   
10.
The extraction of Artemisia hedinii Ostenf. et Pauls(A. hedinii) were rough and further isolated by chromatographic separation technology, and the antifungal activity of the component was evaluated by the the spore germination method. Furthermore, the composition of antimicrobial components was analyzed by high performance liquid chromatography-mass spectrometry (HPLC-MS). The results showed that 13 kinds of components(Fr.1-Fr.13) were rough isolated from the extraction of A. hedinii, in which the component Fr.5 showed the best antifungal activity. Four kinds of components (Fr.5.1-Fr.5.4) were obtained by the further separation of the component Fr.5. The EC50 of A. hedinii crude extraction on Alternaria alternate (A.alternate) spores was 5.04 g/L, and that of the component Fr.5.2 was 0.57 g/L. The HPLC-MS results showed that the components of Fr.5.2 mainly contained deoxy double hydroxyl artemether (17 %),deoxy dihydroartemisinin (43.65 %) and deoxyartemisinin (16.15 %). The content of dihydroartemisinin of component Fr.5.2 was calculated as 40.95 % by using dihydroartemisinin as the standard. The EC50 of dihydroartemisinin on A.alternate was 2.70 g/L, indicating that the major antifungal matter in component Fr.5.2 was artemisinin derivatives. © 2018, Editorial Board of «Chemistry and Industry of Forest Products». All right reserved.  相似文献   
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