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1.
通过对人体五行微量元素与食物吸收微量元素影响因素分析,采用“健脾开胃”均衡食疗配方,对百草元营养包的研制作了全面的介绍和论述。经临床患者食疗结果表明:总有效率为98%.该产品达到了预期设计目标与均衡食疗要求.  相似文献   
2.
采用活化酯法,将马兜铃酸A分别与牛血清蛋白(BSA)和卵清蛋白(OVA)偶联,得到免疫抗原马兜铃酸A-BSA和包被抗原马兜铃酸A-OVA.利用马兜铃酸A-BSA免疫Bal b/c小鼠,制得鼠单克隆抗体1A11,单抗效价为2×104;单抗为IgG1类,轻链为κ型;与其结构类似物马兜铃酸B、C和D的交叉反应率分别为2.8%,3.5%和31.2%.基于抗马兜铃酸A单克隆抗体的间接竞争酶联免疫分析方法(icELISA)的IC50为1.9 μg/L,检测范围为0.5~7.5 μg/L.icELISA添加回收率为86%~97%,相对标准偏差在5.2%~11.1%之间.利用所建立的icELISA测定了6个中药材和5个中成药中马兜铃酸A的含量,并用高效液相色谱法(HPLC)进行了验证,其中关木通、广防己、天仙藤、马兜铃和青木香中均检测出马兜铃酸A,而川木通和5个中成药中未检测到马兜铃酸A.结果表明: 本方法可用于中药中马兜铃酸A的快速检测.  相似文献   
3.
Nobel laureate William A. Fowler recalls his early education in physics; his part in the history of nuclear physics at the California Institute of Technology in the 1930s; parallel efforts elsewhere, particularly at Berkeley and the Department of Terrestrial Magnetism in Washington,D.C.; his contacts with J. Robert Oppenheimer; and his work with Charles C. Lauritsen and Tommy Lauritsen before and after World War II.John Greenberg received his Ph.D. degree from the University of Wisconsin and was Caltech research fellow in history from 1980–1984. The Editors were saddened to learn that he died while this interview was in press. Requests for reprints may be directed to Judith R. Goodstein, Institute Archives 015A-74, Caltech, Pasadena, CA 91125 USA; e-mail: jrg@caltech.edu.  相似文献   
4.
This paper presents an international proficiency testing program (APLAC T065) on two trace elements, cadmium and lead, in an herbal sample, Herba Desmodii Styracifolii. The program was registered with a total of 109 laboratories from 42 countries. The assigned reference values of the analytes for performance assessment were provided by the organizers using an accurate gravimetric isotope dilution inductively coupled plasma-mass spectrometry technique. z-Score was used as the numerical indicator to interpret participants' competence. The between-laboratory variations for cadmium and lead were respectively 18.7% and 19.8% and the consensus values were found to be consistent with the assigned reference values. Twenty-two participants gave at least one unsatisfactory z-score, but the performance of the majority of participants on the analysis of cadmium and lead in herbal matrix was generally good when compared with the assigned reference values.  相似文献   
5.
荆芥中微量元素的初级形态分析   总被引:1,自引:0,他引:1  
刘冬莲 《光谱实验室》2009,26(5):1105-1108
对荆芥中微量元素铁、铜、锰、锌的初级形态进行了研究,采用火焰原子吸收光谱法(FAAS)测定了各微量元素的含量。结果表明,以HNO3和H2O2混合液作为消解剂能彻底消解样品。各元素在水提液中的含量均低于原药材中的含量,微量元素铁、铜、锰、锌的提取率分别为:19.7%,20.5%,38.6%和34.5%,大部分微量元素仍残留在残渣中。  相似文献   
6.
测定了百草元营养包中含有人体所必需的十四种微量元素和几种宏量元素,从微量元素与保健的角度,观察了百草元营养包补充人体常见缺乏的微量元素和治疗多种常见慢性病的效果,总有效率达89%。  相似文献   
7.
Artemisinin is an endoperoxide sesquiterpene lactone isolated from the Chinese medicinal plant Artemisia annua L. It has been widely used in South-East Asia and Africa as an effective drug against sensitive and multidrug-resistant Plasmodium falciparum malaria. A monoclonal antibody (mAb), designated as 3H2, was generated with artesunate–bovine serum albumin conjugate as the immunogen. mAb 3H2 was used to develop a highly sensitive and specific indirect competitive enzyme-linked immunosorbent assay (icELISA) for artemisinin. The concentration of analyte producing 50% of inhibition (IC50) and the working range of the icELISA were 1.3 and 0.2–5.8 ng/mL, respectively. The mAb 3H2 recognized the artemisinin analogs artesunate, dihydroartemisinin, and artemether with cross-reactivity of 650%, 57%, and 3%, respectively, but negligibly recognized deoxyartemisinin and the artemisinin precursors arteannuin B and artemisinic acid. The average recoveries of artemisinin fortified in A. annua samples at concentrations from 156 to 5,000 μg/g determined by icELISA ranged from 91% to 98%. The icELISA was applied for the determination of artemisinin in different wild A. annua samples and the results were confirmed by high-performance liquid chromatography (HPLC) analysis. The correlation coefficient (R 2) between the two assays was larger than 0.99, demonstrating a good agreement between the icELISA and HPLC results. This ELISA is suitable for quality assurance of A. annua L. materials. Figure  Artemisia annua plant and antimalarial drugs derived from artemisinin  相似文献   
8.
本文主要用荧光光谱(FS)、 紫外光谱(UV)从药物分子结构角度研究五种香豆素类中药有效成分CⅠ~CⅤ与牛血清白蛋白(Bovine Serum Albumin, BSA)结合时的构效关系.  相似文献   
9.
中药药对的化学成分研究川芎-赤芍挥发油的GC/MS分析   总被引:9,自引:0,他引:9  
中药药对是复方的最小组成单位,具有中药配伍的基本特点. 药对化学是复方化学的核心内容. 联用色谱和化学计量学方法为中药复杂体系的分离与分辨提供了强有力的工具. 采用GC-MS法分离测定中药药对川芎-赤芍、 单味药川芎和赤芍的挥发油成分,并对其中的重叠色谱峰采用化学计量学解析方法(CRM)进行分辨,得到药对和各单味药的纯色谱曲线和质谱图,药对川芎-赤芍、 单味药川芎和赤芍分别分辨出82,78和57个色谱峰,通过质谱库对分辨的纯组分进行定性,分别得到61,52和33个定性结果,占总含量的90.18%,95.14%和95.82%.  相似文献   
10.
A GC-MS fingerprinting technique based on the essential oil components has been developed for the discrimination of chuanxiong against Chinese Angelica (Angelica sinensis (Oliv.) Diels) or other herbs with similar compositions. The analytical performance of four different extraction methods for the separation of essential oil components have been compared and these include: ultrasound-assisted extraction (UAE), supercritical fluid extraction (SFE), Soxhlet extraction (SHE) and hydro-distillation extraction (HDE). The results showed that UAE was the most effective extraction method, and the operational parameters of UAE were optimized. 3-Butylphthalide, Z-butylidenephthalide, senkyunolide I, senkyunolide H, E-butylidenephthalide, senkyunolide A, neocnidilide, Z-ligustilide and E-ligustilide were tentatively identified in chromatograms of chuanxiong based on their GC-EI-MS data. Similarity coefficient calculations based on correlation methods have been performed on the GC-MS fingerprints. Using an authentic standard Chuanxiong as the reference, the similarity coefficients between the standard and all other chuanxiong samples ranged from 0.90 to 1.0 (with 1.0 being the perfect match), which as a group can be readily separated from the Angelica samples for which the similarity index against the chuanxiong standard ranged from 0.75 to 0.77. Conversely, when an authentic Angelica standard was used as the reference, the respective similarity coefficients fall in the range of 0.70-0.75 and 0.98-1.00 for the chuanxiong and Angelica sample groups. Our results thus demonstrate that the fingerprinting technique developed in the study can indeed discriminate the two herbs with high reliability.  相似文献   
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