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81.
小檗碱-[AuI4]-缔合纳米微粒体系的吸收光谱研究及分析应用 总被引:3,自引:0,他引:3
在0.008 mol·L-1HCl介质中, Au(Ⅲ)与I-形成[AuI4]-; [AuI4]-和小檗碱(BB)通过静电引力作用形成疏水性的(AuI4-BB)缔合物分子. 由于(AuI4-BB)缔合物分子间存在较强的分子间作用力和疏水作用力而生成橙黄色(AuI4-BB)n缔合纳米微粒, 在520 nm处产生一个共振散射峰; 其吸收峰仍位于[AuI4]-的吸收峰350 nm处, 但在可见光范围内的吸光度增大. 在选定条件下, BB浓度在0.8×10-6~20×10-6 mol·L-1范围内与A450 nm呈线性关系. 实验结果表明, (AuI4-BB)n缔合纳米微粒的形成是产生共振散射的根本原因. 相似文献
82.
An optical sensor for berberine, the basic ingredient of the widely used traditional Chinese medicine Coptis Chinensis, based on its intrinsic fluorescence enhanced by butylated-β-cyclodextrin (HDB-β-CD) immobilized in plasticized poly(vinyl chloride) (PVC) membrane has been developed. The drastic enhancement of fluorescence intensity of berberine was attributed to the formation of an inclusion complex between HDB-β-CD and berberine, which has been utilized as the basis of the fabrication of a berberine-sensitive fluorescence sensor. The proposed sensor was quite distinct from those fluorescent sensors for berberine reported so far which relied upon quenching the fluorescence of the sensing reagent immobilized on membrane by berberine. The response mechanism of optode membrane was discussed in detail from the view of molecular dynamics and the optimum steric configuration of the inclusion complex was presented by molecular dynamics simulation. The analytical performance characteristics of the proposed berberine-sensitive sensor were investigated. The sensor can be applied to the quantification of berberine with a linear range covering from 4.0×10−7 to 2.0×10−5 mol l−1 with a detection limit of 8.0×10−8 mol l−1. The sensor exhibits excellent reproducibility, reversibility and selectivity. The recommended method was successfully used for the determination of berberine in pharmaceutical preparations. 相似文献
83.
The root extracts of goldenseal (Hydrastis canadensis L.) are popular phytomedicines for the treatment of gastrointestinal disorders and upper respiratory tract infections. Here we describe a simple and fast capillary zone electrophoresis (CZE) method with ultraviolet detection at 225 nm for the quantification of the major goldenseal constituents, berberine and hydrastine, in herbal remedies containing goldenseal root extracts. Tritoqualine, an antihistaminic drug with a hydrastine-like phthalidisoquinoline structure, was applied as an internal standard. The running buffer was a 1:5 mixture of 500 mM ammonium acetate (adjusted to pH 3.4 with acetic acid) and methanol. Our newly developed CZE method was validated regarding limit of detection (LOD), limit of quantification, linearity, accuracy and precision. For both berberine and hydrastine, the LOD was 1.0 microg/mL and the linearity was obtained between 2.5 and 500 microg/mL. Using our newly developed method, both the alkaloids could be analysed in herbal remedies containing goldenseal root extracts within 8 min. 相似文献
84.
Studies of interactions between drugs and DNA are very interesting and significant not only in understanding the mechanism of interaction, but also for guiding the design of new drugs. However, until recently, mechanisms of interactions between drug molecules and DNA were still relatively little known. It is necessary to introduce more simple methods to investigate the mechanism of interaction. In this study, the interactions of daunorubicin (DNR) or berberine (BER) with DNA and the competitive interactions of DNR and BER with DNA have been studied by alternating penalty trilinear decomposition algorithm (APTLD) combined with excitation-emission matrix fluorescence data. The excitation and emission spectra as well as the relative concentrations of co-existing species in different reaction and equilibrium mixtures can be directly and conveniently obtained by the APTLD treatment. The results obtained are valuable for providing a deeper insight into the interaction mechanism of DNR and BER with DNA. It is proved that the fluorescence spectrum of complex DNR-DNA is different from that of DNR. Furthermore, the present method provides a new way to search for a new non-toxic, highly efficient fluorescent probe. For controversial interaction mechanism of the drugs and DNA, it can provide a helpful verification. 相似文献
85.
Capillary zone electrophoretic studies of interactions of some quaternary isoquinoline alkaloids with DNA constituents and DNA 总被引:1,自引:0,他引:1
Capillary zone electrophoresis was applied for the investigation of interactions of some quaternary isoquinoline alkaloids, namely sanguinarine, chelerythrine, berberine, and jatrorrhizine, with DNA constituents and with DNA. None of these alkaloids attach covalently to nucleotides or to the whole DNA under physiological conditions. The interaction with DNA constituents is a noncovalent complexation based on weak intermolecular forces. Electrostatic attraction participates in the interaction but other types of intermolecular forces are involved as well. Cations were identified as the most probable interacting forms of the alkaloids. The interaction with compounds derived from purine was always stronger than those derived from pyrimidine. All alkaloids behaved analogously and similarly to ethidium bromide, the classic DNA intercalator. Stability constants K (in l.mol(-1)) for sanguinarine and chelerythrine in phosphate buffer of pH 7.4 (I(S) = 30 mM) ranged from tens to hundreds. 相似文献
86.
87.
Xiangji Zeng 《Chromatographia》1998,48(7-8):589-590
Summary Berberine absorption by patients with ischemic heart failure (IHF) after oral administration and the relationship between
clinical effect and plasma berberine concentration are studied. Plasma samples were pretreated by chloroform extraction. Berberine
was determined on a μBondapak column with acetonitrile-phosphoric acid mobile phase and UV detection. The limit for berberine
in plasma was 8 ng mL−1 for an injection volume of 50 μL. Average berberine recovery was 96.5%. Results showed that improvements in symptoms were
more significant for patients with plasma berberine concentration>0.1 mg L−1 than for those with<0.1 mg L−1. Plasma berberine monitoring may be helpful in the treatment of patients with IHF. 相似文献
88.
表面增强拉曼光谱研究小檗碱与DNA的相互作用 总被引:8,自引:0,他引:8
用表面增强拉曼光谱研究了小檗碱(BER)与小牛胸腺DNA(ct DNA)的相互作用,并对重要谱峰进行了归属。在Ag胶体系中,小檗碱分子的拉曼信号增强显著,表明小檗碱阳离子键合到银胶粒子的表面。加入ct NA之后,小檗碱分子的大部分SERS带的强度进一步增加,而仅有少数几个带的信号强度趋于消失,可能是小檗碱分子的异喹啉部分键合到DNA的小沟槽,小檗碱与DNA的相互作用模式主要是通过静电力及疏水相互作用,吸收光谱表明,Ag胶体系的存在并未改变小檗碱分子与DNA的相互作用模式。 相似文献
89.
采用超声波法在2种条件下即(1)先超声处理,后放置过夜;(2)先放置过夜,后超声处理,对黄瓜籽粉中盐酸小檗碱进行提取,利用分光光度法测定盐酸小檗碱的含量,检测波长为426nm。回归方程y=0.00393+1.28929x(mg/10mL),r=0.9999;盐酸小檗碱浓度在0.099—0.796mg/10mL范围内与吸光度呈线性关系。2种方法的平均含量分别为2.4043、1.4797mg/g。平均回收率分别为94.96%、107.32%。实验结果表明,方法(1)较方法(2)提取率高。分光光度法用于黄瓜籽粉中盐酸小檗碱的含量测定,简便,可靠,快捷。 相似文献
90.
Interactions between small molecules with biopolymers e.g. the bovine serum albumin (BSA protein), are important, and significant information is recorded in the UV-vis and fluorescence spectra of their reaction mixtures. The extraction of this information is difficult conventionally and principally because there is significant overlapping of the spectra of the three analytes in the mixture. The interaction of berberine chloride (BC) and the BSA protein provides an interesting example of such complex systems. UV-vis and fluorescence spectra of BC and BSA mixtures were investigated in pH 7.4 Tris-HCl buffer at 37 °C. Two sample series were measured by each technique: (1) [BSA] was kept constant and the [BC] was varied and (2) [BC] was kept constant and the [BSA] was varied. This produced four spectral data matrices, which were combined into one expanded spectral matrix. This was processed by the multivariate curve resolution-alternating least squares method (MCR-ALS). The results produced: (1) the extracted pure BC, BSA and the BC-BSA complex spectra from the measured heavily overlapping composite responses, (2) the concentration profiles of BC, BSA and the BC-BSA complex, which are difficult to obtain by conventional means, and (3) estimates of the number of binding sites of BC. 相似文献