排序方式: 共有54条查询结果,搜索用时 15 毫秒
41.
42.
中国科学院高能物理研究所建造了一台基于加速器的硼中子俘获治疗(BNCT)实验装置。射频功率源系统为352.2 MHz射频四极加速器(RFQ)提供高频功率,使束流离开RFQ时,其能量达到3.5 MeV。BNCT射频功率源系统主要包括速调管功率源、数字低电平控制系统、射频传输系统。本文介绍了BNCT射频功率源系统,主要包括物理需求、系统组成、关键设备、安装和调试。目前该装置已进行动物实验,加速器打靶束流功率4.3 kW,加速器射频功率源系统运行稳定。 相似文献
43.
The one-pot reaction of Me3NBH2CN with Et3O+BF4− followed by addition of BF3·Et2O and water produces a trimethylamine derivative of fluorocyclocarboxyboranylamine, Me3NBH2C(O2BF2NH2) ( 1 ) in 36.0% yield. Compound 1 undergoes exchange reaction between the exo-Me3N moiety and piperidine or pyridine to produce the corresponding piperidine-substituted fluorocyclocarboxyboranylamine ( 2 ) or pyridine-substituted fluorocyclocarboxyboranylamine ( 3 ) in 51.2% or 42.4% yields, respectively. The new compounds were characterized by 1H, 13C, 11B, and 19F nuclear magnetic resonance spectroscopy; Fourier-transform infrared spectroscopy; and elemental analyses and the crystal structure of 1 was determined to confirm its molecular geometry. The in vitro killing effects of 1 , along with its toxicity measurements and molecular docking interactions with matrix metalloproteinases showed a potential promise of such species as both boron neutron capture therapy and boron neutron capture synovectomy agents in the treatment of tumors and rheumatoid arthritis, respectively, in the presence of slow neutrons. 相似文献
44.
Václav Šícha Bohumil Štíbr Bohumír Grüner Clara Viñas 《Journal of organometallic chemistry》2009,694(11):1599-281
The treatment of 1,2-, 1,7- and 1,12-carbaborane lithiated isomers with [3,3′-Co-8-(CH2CH2O)2-(1,2-C2B9H10)-(1′,2′-C2B9H11)] (1) at molar ratios 1:1 or 1:2 at room temperature in THF leads generally to the formation of a series of orange double-cluster mono and dianions. These were characterized by NMR and MS methods as [1′′-X-1′′,2′′-closo-C2B10H11]−, [2]−; [1′′-X-1′′,7′′-closo-C2B10H11]−, [3]− and [1′′-X-1′′,12′′-closo-C2B10H11], [4]− for the monoanions, whereas [1′′,2′′-X2-1′′,2′′-closo-C2B10H10]2−, [2]2−; [1′′,7′′-X2-1′′,7′′-closo-C2B10H10]2−, [3]2−; and [1′′,12′′-X2-1′′,12′′-closo-C2B10H10]2−, [4]2− for the dianions (where X = 3,3′-Co-8-(CH2CH2O)2-(1,2-C2B9H10)-1′,2′-(C2B9H11)). Moreover, these borane-cage subunits can be easily modified via attaching variable substituents onto cage carbon and boron vertices, which makes these compounds structurally flexible potential candidates for BNCT of cancer and HIV-PR inhibition. 相似文献
45.
46.
《Surface and interface analysis : SIA》2006,38(3):121-125
Successful anticancer therapies will have the ability to selectively deliver compounds to target cells while sparing normal tissue. Currently, methods to determine the distribution of compounds with very high sensitivity and subcellular resolution are still unavailable. Laser secondary neutral mass spectrometry (laser‐SNMS) and time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS) are capable of detecting atoms and molecules with high sensitivity and a spatial resolution of up to 80 nm. The use of such methods requires special preparation techniques that preserve the morphological and chemical integrity of living cells. In this paper, the ability of laser‐SNMS to study transportation processes in animals of boron‐containing compounds for boron neutron capture therapy will be discussed. The data show that with laser‐SNMS it is possible to measure the distribution of these compounds in tissues with subcellular resolution, and that laser‐SNMS is a very powerful tool for locating anticancer drugs in tissues. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
47.
Mohamed E. El‐Zaria Prof. Dr. Hyun Seung Ban Dr. Hiroyuki Nakamura Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(5):1543-1552
A novel series of boronated porphyrins for potential use in boron neutron capture therapy (BNCT) and photodynamic therapy (PDT) for tumor suppression is described. Protoporphyrin IX {i.e., bis(α‐methyl‐β‐pentylethylether)protoporphyrin IX, and bis(α‐methyl‐β‐dodecanylethylether)protoporphyrin IX} bearing polyhedral borane anions (B12H11SH2?, B12H11NH3?, or B12H11OH2?) were synthesized with reasonable yields. Modification of the protoporphyrin IX structure was achieved by variation of the lengths of the alkyl chains (pentyl and dodecanyl) attached through ether linkages to the former vinyl groups. The goal of this modification was to develop boronated porphyrins with chemical and physical properties that differed from those of protoporphyrin IX. Performance of an MTT assay with each derivative revealed that the synthesized boronated porphyrins showed low cytotoxicities in a variety of cancer cells. Of these compounds, B12H11NH22?‐conjugated porphyrin induced a significant increase in the level of boron accumulation and PDT efficacy against HeLa cells. 相似文献
48.
Basilico F Sauerwein W Pozzi F Wittig A Moss R Mauri PL 《Journal of mass spectrometry : JMS》2005,40(12):1546-1549
Boron neutron capture therapy (BNCT) is a promising binary treatment for cancer. BNCT is based on the ability of the nonradioactive isotope (10)B to capture, with a very high probability, thermal neutrons. This nuclear reaction results in two particles (an alpha and a lithium nucleus). The particles have a high biological effectiveness, which is limited in tissue to approximately the diameter of one cell. If the reaction can be limited to a tumor cell, the physical characteristic opens up the possibility to selectively destroy cancer cells, while sparing the surrounding healthy tissue. Quality control of (10)B-containing compounds and their distribution at present are very important, and different analytical methods have been developed, such as time-of-flight secondary ion mass spectrometry (TOF-SIMS), electron energy loss spectrometry (EELS), prompt gamma analysis and inductively coupled plasma-optical emission spectrometry (ICP-OES). These methods allow the analyses of (10)B, but it is not possible to characterize the specific molecular compounds containing (10)B. For this reason, we propose a fast and quantitative method that permits the determination of closo-undecahydro-1-mercaptododecaborate (BSH) and (10)boron-phenylalanine (BPA) and their eventual metabolites. In particular, (10)B-containing compounds are detected by means of flow-injection electrospray tandem mass spectrometry (FI/ESI-MS/MS). This approach allows the identification of Boron compounds, BSH and BPA, using tandem mass spectrometry, and quantitative analysis is also possible (c.v. +/-4.7%; n = 5; linear range 10-10,000 ng/ml). Furthermore, (10)B-containing compounds were detected in actual biological sample (urine and plasma, diluted 10,000- and 1,000-fold, respectively) injecting a small volume (1 microl) of diluted samples. 相似文献
49.
Leonid O. Kononov Anna V. Orlova Boris G. Kimel Vladimir I. Bregadze 《Journal of organometallic chemistry》2005,690(11):2769-2774
A novel 1,2-dicarba-closo-dodecaborane-lactose conjugate 4c, when dissolved in water or methanol, is subject to unexpected deboronation in neutral conditions leading to the formation of the corresponding nido-counterpart (5) as detected by 11B NMR spectroscopy. After heating the aqueous solution of the conjugate 4c at 60 °C for 17 h pure 1,2-dicarba-nido-undecaborane-lactose conjugate 5 was obtained. 相似文献
50.
George W. Kabalka Guang-Qiang Cheng Peter Bendel Peggy L. Micca Daniel N. Slatkin 《Magnetic resonance imaging》1991,9(6)
In vivo boron-11 magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) were performed on a rat that had been infused with a potential boron neutron capture therapy agent, Na4B24H22S2, using methods for detecting nuclei with a short T2 relaxation time. MRI and MRS were also performed on a euthanized rat that had been similarly infused in vivo. Boron-11 spectral intensities decreased in the living rat over a 25-h period. The results demonstrate the capability of MRI and MRS to noninvasively monitor the distribution and excretion of boron agents in vivo. 相似文献