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31.
A colloidal gold conjugated anti-baicalin monoclonal antibody (anti-BA MAb) was prepared and used in an immunochromatographic assay (ICA) for BA in Scutellariae Radix and Kampo medicines. This competitive ICA uses an anti-BA MAb which shows a high specificity for BA and baicalein. Its advantages include a short assay time (15 min), no dependence on any instrumental systems, and it can detect BA in plant materials and Kampo medicines. The limit of detection for the ICA was found to be around 0.6 μg mL−1of baicalin. Moreover, the usefulness of the combination of indirect competitive ELISA and the ICA using anti-BA MAb as a quality control method was confirmed for analysis of BA in Scutellariae Radix and Kampo medicines with a sufficient sensitivity (200 ng mL−1 to 2 μg mL−1), obtainable in an easy and timely manner.  相似文献   
32.
Water-ethanol mixtures exhibit interesting anomalies in their macroscopic properties. Despite a lot of research, the origin of the anomalies and the microscopic structure itself is still far from completely known. We have utilized the synchrotron x-ray Compton scattering technique to elucidate the structure of aqueous ethanol from a new experimental perspective. The technique is uniquely sensitive to the local molecular geometries at the angstrom and subangstrom scales. The experiments reveal two distinct mixing regimes in terms of geometry: the dilute 5 mol % and the concentrated >15 mol % regimes. By comparing with pure liquids, the former regime is characterized by an intramolecular and the latter by an intermolecular change. The findings bring new light to evaluating the hypothesis of formation of clathratelike structures at the dilute concentrations.  相似文献   
33.
Pyrrole–imidazole (PI) polyamides bind to the minor groove of the DNA duplex in a sequence‐specific manner and thus have the potential to regulate gene expression. To date, various types of PI polyamides have been designed as sequence‐specific DNA binding ligands. One of these, cysteine cyclic PI polyamides containing two β‐alanine molecules, were designed to recognize a 7 bp DNA sequence with high binding affinity. In this study, an efficient cyclization reaction between a cysteine and a chloroacetyl residue was used for dimerization in the synthesis of a unit that recognizes symmetrical DNA sequences. To evaluate specific DNA binding properties, dimeric PI polyamide binding was measured by using a surface plasmon resonance (SPR) method. Extending this molecular design, we synthesized a large dimeric PI polyamide that can recognize a 14 bp region in duplex DNA.  相似文献   
34.
Hybrid stars composed of a strange matter core surrounded by neutron matter are investigated. We apply star models based on phenomenological equations of state (EOS) from nuclear reactions including a phase transition between the hadronic phase and the quark gluon plasma. For specific equations of state hybrid stars might exist. While the nuclear part of the EOS has only a minor influence on the properties of hybrid stars, the EOS for the quark gluon phase has a crucial impact on the existence of such objects.  相似文献   
35.
Two identical heavy-ions represented by Fermi gases of cubic shape collide and coalesce to form a rectangular shape. The energy release due to the coalescence is estimated by using simple model and the energy of the coalescent nucleus is calculated as a function of the shape parameters. We find that a rectangular shape, which is compressed in the direction of collision, is energetically more favoured. The structure of the coalescent nucleus is next investigated. It is expressed as a superposition ofn-particlen-hole states. We find that the probability distribution ofn-particlen-hole states has a Gaussian form and its peak value ofn is proportional to the excitation energy, while the width is proportional to the square root of the excitation energy. The average energy of then-particlen-hole states is found to be approximately F whereε F is the Fermi energy. Finally discussions are given in connection with experimental data.  相似文献   
36.
The electronic structures of both cubic and tetragonal ZeO2 were calculated by the discrete-variational (DV)-Xα cluster method. The results show that ZrO2 is fairly ionic, and its ionicity is different for the cubic and the tetragonal phases. The bond order and the magnitude of the energy gap between the highest occupied O-2p level and the lowest unoccupied Zr-4d level also depend on the crystal structure. These changes in the electronic states seem to be closely related to the phase stability of ZrO2.  相似文献   
37.
In-beamγ ray spectroscopy withγ singles spectra,γγ coincidences andγ ray angular distributions has been performed with several target-projectile combinations:natCa +32S,natCa +40Ca,54Fe +14N,58Ni +12C,58Ni +14N,66Zn +16O,68Zn +16O. Level schemes of66Ge,68Ge,69As,70Se,74Kr,80Sr and82Sr have been deduced. The following level energies and spin-parity assignments have been found:66Ge: 957.4 keV, 2+; 1693.7; 2174.7, (4+); 3685.7; 4207.5;68Ge: 1015.8, 2+; 1777.9, 2+; 2267.9, 4+; 2428.8, 3(+); 2649.1, 3?; 3582.3, (5?); 3649.3, (5?); 3696.2, (6+); 3883.3, (6?); 4054.4, (7?); 4454.6; 4837.3;69As: 98.2; 164.6;789.6;863.2; 1306;2160;2210.4;2831.5;3258.3;3263.5;3991.1;5195.7;70Se: 945.4, 2+; 1600.9; 2039.4, (4+);74Kr: 455.7, 2+; 1013.5, (4+); 1781.5;80Sr: 385.4, 2+; 980.2, (4+); 1763.2, (6+);82Sr: 573.4, 2+; 1328.5,(4+); 2229.6,(6+). γ ray activity spectra have been measured after the bombardment of natural Ca with32S. The half-life of the new isotope69Se has been found to be 27±3 sec. Recoil distance Doppler-shift measurements have been performed with the reactions62,64Ni,66zn(16O, 2n)76, 78 Kr,80Sr. The following half-lives have been determined:76Kr: 423.8 keV, 2+, 37±5 psec; 1034.2,4+, 5.7±1.6;78Kr: 455.3, 2+, 25±3; 1120.0, 4+, 3.8±1;80Sr: 385.4, 2+, 44±6. The energy and half-life systematics of the first excited state of even-even nuclei suggest a maximum of nuclear deformation in the region 28≦N, Z≦50 near 38 76 Sr38 or 40 78 Zr38.  相似文献   
38.
A method for the synthesis of 1,1‐diborylalkenes through a Brønsted base catalyzed reaction between terminal alkynes and bis(pinacolato)diboron has been developed. The procedure allows direct synthesis of functionalized 1,1‐diborylalkenes from various terminal alkynes including propiolates, propiolamides, and 2‐ethynylazoles.  相似文献   
39.
Disulfide‐containing IgG‐, Fc‐, or albumin‐based prodrugs that rely on FcRn‐trafficking by endothelial cells for prolonged circulation in the body might be hampered by premature bio‐reduction processes during FcRn‐mediated recycling events. A detailed bio‐reduction analysis of redox‐sensitive albumin conjugates in two FcRn‐expressing cell lines has been performed. The obtained results indicate that the FcRn‐mediated recycling pathway is not (or is only poorly) bio‐reducing.  相似文献   
40.
Bio-based multi-functional epoxides (1) such as bis-, tri-, and tetra-epoxides were synthesized by ene-thiol reactions between limonene oxide and polyhydric thiols. A cross-linking reaction of 1 with branched polyethyleneimine (BPEI) afforded the corresponding network polymers 2 with relatively high thermal resistance in high yields.  相似文献   
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