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101.
102.
Suzuki Masayasu Watamabe Nobuyuki Tamiya Eiichi Kataoka Tetsuro Tokunaga Tohru Karube Isao 《Applied biochemistry and biotechnology》1987,15(3):191-200
A novel tumor-detection system consisting of complementmediated cytolytic reaction and an image processing system was developed
for the simple and rapid determination of tumor cells.
The present system consists of a CCD image sensor, image memory board, personal computer, and microscope.
When monoclonal antibody 3C4, which is specific to the guinea pig hepatoma L-10, was added to cell suspension, only L-10 cytolysis
occurred. Cytolysis caused a decrease in brightness of the cells observed by phase-contrast microscopy. The phase contrast
image of the cells before cytolysis was converted to a digitalized signal and stored in computer memory. After cytolysis,
a brightness threshold above that of lysed cells was subtracted from the digitalized signal and compared to the signal stored
before reaction.
L-10 cells in mixed cell suspension were determined specifically by the system. Measurement time was only 2 sec and overall
time, including reaction time, was approximately 30 min. Since this method does not require a cell washing process, automation
of the whole system is possible. 相似文献
103.
冠醚化二苯甲酮的合成及其光物理行为 总被引:1,自引:0,他引:1
本文报道采用在多聚磷酸中酰化的方法,合成了冠醚化二苯甲酮1~8。它们与叔胺类共用可能被用作光引发剂。为此,用紫外光谱详细研究了这些化合物及其络合后的光物理行为。还提及化合物3和4作为紫外吸收剂的可能性。 相似文献
104.
A nonenzymatic glucose sensor with good selectivity for the ascorbic acid oxidation is presented. After the gold polycrystalline electrode was subjected to amalgamation treatment, two advantageous effects were observed. One is the enhancement of the surface roughness and the other is an increase in the catalytic current in the glucose oxidation. Besides the known first effect, the latter provided another advantageous effect in a fabrication of nonenzymatic glucose sensor. Using a gold electrode subjected to amalgamation treatment for 60 s, two calibration curves for glucose oxidation at two different potentials of ?0.1 V and 0.25 V were obtained and compared. At the potential of ?0.1 V, at which no ascorbic acid was oxidized and no interference effect was observed, a current sensitivity of 16 μA cm?2 mM?1 from zero to 10 mM glucose concentration range was obtained. At the other potential of 0.25 V, at which ascorbic acid was easily oxidized, a satisfactory calibration curve with negligible ascorbic acid interference was also obtained together with a more enhanced current sensitivity of 32 μA cm?2 mM?1. 相似文献
105.
There is a need to develop reliable portable analytical systems for on-site and real-time biomonitoring of lead (Pb) from both occupational and environmental exposures. Saliva is an appealing matrix since it is easily obtainable, and therefore a potential substitute for blood due to existing reasonably good correlation between Pb levels in blood and saliva. The microanalytical system is based on flow-injection/stripping voltammetry with a wall-jet (flow-onto) microelectrochemical cell. Samples that contain as little as 1% saliva can cause electrode fouling, resulting in significantly reduced responsiveness and irreproducible quantitations. In addition, incomplete Pb release from salivary protein can also yield a lower Pb response than expected. This paper evaluates the extent of in vitro Pb-protein binding and the optimal pretreatment for releasing Pb from the saliva samples. Even in 50% by volume of rat saliva, the electrode fouling was not observed, due to the appropriate sample pretreatment and the constant flow of the sample and acidic carrier that prevented passivation by the protein. The system offered a linear response over a low Pb range of 1-10 ppb, low detection limit of 1 ppb, excellent reproducibility, and reliability. It also yielded the same Pb concentrations in unknown samples as did the ICP-MS. These encouraging results suggest that the microanalytical system represents an important analytical advancement for real-time non-invasive biomonitoring of Pb. 相似文献
106.
Christian Huber Christian Krause Tobias Werner Otto S. Wolfbeis 《Mikrochimica acta》2003,142(4):245-253
This article describes the preparation and performance of an optical sensor for continuous measurement of chloride at extracellular (serum) levels (20–200mM). The sensor is based on dynamic quenching of the fluorescence of lucigenin which was photo-immobilized on a hydrogel. Quenching occurs via a collisional mechanism, and the decrease in fluorescence intensity on exposure to 100mM chloride typically is –60%. It allows the determination of chloride in the 1 to 200mM concentration range, with a precision of ±3mM at 120mM. Bromide, iodide and salicylate act as interferents, while the effect of pH and oxygen is negligibly small. The sensor displays strong fluorescence intensity, excellent reproducibility, long-term stability, response times in the order of 2–5min, and is used in a commercial serum and blood chloride analyzer.Received January 21, 2003; accepted April 6, 2003
Published online July 28, 2003 相似文献
107.
The oscillating conditions for a series piezoelectric quartz crystal (SPQC) are proposed and verified experimentally. The influence of the cell constant and oscillator phase on the oscillational ability of the SPQC was investigated. It is shown that the SPQC possesses excellent oscillational ability in low or high conductivity solutions, but in solution of intermediate conductivity, the oscillational ability decreases with increasing oscillator phase or decreasing cell constant, sometimes resulting in a cease-to-oscillate zone. The SPQC was applied to determine the urease activity in plant seeds with a detection limit of 0.004 U ml−1, based on the change in conductivity. 相似文献
108.
足球分子及有关碳笼的电子结构 总被引:1,自引:0,他引:1
本文评述了激光气化产生的碳原子簇的电子结构和活性。足球分子具有球面芳香性。我们用INDO/2和INDO/CI系列方法。研究了足球分子及其异构体的电子结构和UV谱。足球分子的计算结果是只有一条低频带(366.4nm),与实验结果(386.0nm)符合得很好。 相似文献
109.
110.
Fumio Hamada Kyoko Ishikawa Riko Ito Hisanori Shibuya Sanyo Hamai Iwao Suzuki Tetsuo Osa Akihiko Ueno 《Journal of inclusion phenomena and macrocyclic chemistry》1994,20(1):43-51
-Cyclodextrin with two sodium anthranilate moieties (1) has been prepared as a sensor for detecting organic compounds including terpenoids and steroids. Compound1 shows a pure monomer fluorescence whose intensity is increased or decreased upon addition of the guest species examined. In this system, the sodium anthranilate moieties act either as a spacer, which enables the cyclodextrin to form a 1:1 host-guest complex by narrowing the -cyclodextrin cavity, or as a hydrophobic cap.1 recognizes steroids with much higher sensitivity than terpenoids, in which the appended moieties act as a hydrophobic cap for terpenoids and a spacer for steroids, respectively. 相似文献