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21.
天然抗癌药物--紫杉醇   总被引:18,自引:0,他引:18  
王正平 《应用科技》2004,31(1):56-58
介绍了人们在不断提高天然植物红豆杉——紫杉醇提取技术的同时,利用人工栽培、半合成、全合成、生物合成、真菌发酵、植物组织细胞培养等现代科技手段获取紫杉醇,为解决天然资源的严重不足和紫杉醇的临床应用提供了可能.  相似文献   
22.
豌豆不同生长期用不同浓度的硫酸锰溶液进行叶面喷施,结果表明,在幼苗期、现蕾期和开花期喷施不同浓度硫酸锰溶液,能增强豌豆叶片的SOD活性和CAT活性,降低O2^*-生成速率和MDA含量.在豌豆生长的幼苗期、现蕾期和开花期叶面喷施0.1%~0.2%的硫酸锰溶液能促进豌豆的生长和产量的增加。  相似文献   
23.
Increasing applications and markets for essential oils could bring new opportunities for cost-effective and sustainable management of unused forestry biomass; however, better knowledge of the production and application of such essential oils is necessary. The objective of this work is to contribute to greater knowledge of the essential oil production on a pilot scale from foliage biomass of wild shrubs and tree residues produced in some forestry enhancement operations and to study their antioxidant capacity (ORAC—oxygen radical absorbance capacity). Fresh biomass (twigs) of seven species (E. globulus, E. nitens, P. pinaster, P. sylvestris, R. officinalis, C. ladanifer, and J. communis) was manually collected in Spain in two different periods and was ground at 30 mm and distilled in a 30 L stainless steel still with saturated steam. The essential oil components were identified by GC–MS and quantified by GC–FID, and their antioxidant activity was determined with the ORAC method. Promising results on essential oil yield were obtained with E. globulus, E. nitens, R. officinalis, and J. communis. All essential oils studied exhibited antioxidant capacity by the ORAC assay, particularly that from C. ladanifer. Moreover, oxygenated sesquiterpenes contents, one of the minor components of oils, were significantly correlated with ORAC values.  相似文献   
24.
The feasibility of gingko (Gingo Biloba) foliage as a passive bio-monitor for organochlorine pesticides in air was explored. The accumulation patterns of hexachlorocyclohexanes (HCHs), dichlorodiphenyl- trichloroethanes (DDTs) and hexachlorobenzene (HCB) in gingko foliage were similar; the amounts of HCHs, DDTs and HCB increased with foliage growth in spring and decreased thereafter. This accumu-lation pattern is likely related to the growing process of the gingko foliage, which was observed for the first time in our work, giving a piece of evidence for the "bud burst effect" in plants. Compared with those in pine needles in 1980's, the residual levels of HCHs and DDTs have declined obviously in Bei-jing, indicating that the ban on the production and use of organochlorine pesticides (OCPs) in our country is effective; however, the amount of HCB has increased, indicating great progress of chemical industry in Beijing. The analysis for the source of OCPs in the gingko foliage showed that the technical HCHs and DDTs were used largely in history, but were not used in recent years. A little lidane has been used and there was a new input of o,p′-DDT in recent years; dicofol usage may be the main source of o,p′-DDT. Concentrations of HCHs, DDTs and HCB in gingko foliages were similar to those in pine nee-dles in the corresponding period and there is a strong positive correlation between the OCPs concen-tration data obtained from these two kinds of trees. It presents no difference in the accumulation style between these two kinds of trees. The level of OCPs in the gingko foliage reflects the pollution status of OCP in air. The result of this work shows that the gingko foliage can be used as a bio-monitor of OCPs in air.  相似文献   
25.
目的 通过口服大剂量银杏叶制剂测定家犬血浆中的抗氧化指标 ,以便进一步了解银杏叶制剂的药理学作用。方法 用家犬 6只 ,按 10 0mg/kg剂量一次经口服给予银杏叶胶囊 ,于选定时间点从前肢内侧皮下静脉取血5 0mL ,分离血浆 ,测定血浆中抗氧化指标含量。结果 给药后家犬血浆中超氧化物歧化酶 (SOD)的活性较给药前有所降低 ,在 7~ 2 4h之间降低程度更加明显。丙二醛 (MDA)的含量在给药 5h以内有所降低 ,7~ 2 4h之间MDA含量有所增加。结论 银杏叶制剂剂量过大 ,抗氧化能力减弱 ,这是由于产生的·O2 - 在体内大量蓄积造成的  相似文献   
26.
受土壤和环境因素的影响,新疆果树患缺铁性黄化病日益增多,通过将硫酸亚铁施入土壤、叶面喷施和树干注射,以及改良土壤、果树育种等途径可予矫治.  相似文献   
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