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81.
A new device to prevent erroneously focused shock waves to the renal parenchyma during extracorporeal shock wave lithotripsy (ESWL) has been developed; an anti-miss-shot control device (AMCD) and experiments have been conducted to evaluate its effectiveness. For shock wave generation and stone localization, piezoceramic elements (PSE) and ultrasound localization, respectively were used. After stone localization, probing ultrasounds (PU) were emmitted from the PSE towards the focal region and the reflected sound levels (RSL) were monitored by the PSE which also functioned as a microphone. A direct hit by the PU to the stone or a miss was judged from the RSL, i.e. a high RSL indicates a direct hit and a low RSL indicates a miss. Shock waves were generated only when the RSL exceeded the level which indicated a direct hit. The experimental results showed that the injury to the renal parenchyma was decreased by using the AMCD. Clinical application of the AMCD is expected to increase the safety of ESWL.This article was processed using Springer-Verlag TEX Shock Waves macro package 1990. 相似文献
82.
Culture of cells as three-dimensional (3D) aggregates can enhance in vitro tests for basic biological research as well as for therapeutics development. Such 3D culture models, however, are often more complicated, cumbersome, and expensive than two-dimensional (2D) cultures. This paper describes a 384-well format hanging drop culture plate that makes spheroid formation, culture, and subsequent drug testing on the obtained 3D cellular constructs as straightforward to perform and adapt to existing high-throughput screening (HTS) instruments as conventional 2D cultures. Using this platform, we show that drugs with different modes of action produce distinct responses in the physiological 3D cell spheroids compared to conventional 2D cell monolayers. Specifically, the anticancer drug 5-fluorouracil (5-FU) has higher anti-proliferative effects on 2D cultures whereas the hypoxia activated drug commonly referred to as tirapazamine (TPZ) are more effective against 3D cultures. The multiplexed 3D hanging drop culture and testing plate provides an efficient way to obtain biological insights that are often lost in 2D platforms. 相似文献
83.
Douville NJ Zamankhan P Tung YC Li R Vaughan BL Tai CF White J Christensen PJ Grotberg JB Takayama S 《Lab on a chip》2011,11(4):609-619
Studies using this micro-system demonstrated significant morphological differences between alveolar epithelial cells (transformed human alveolar epithelial cell line, A549 and primary murine alveolar epithelial cells, AECs) exposed to combination of solid mechanical and surface-tension stresses (cyclic propagation of air-liquid interface and wall stretch) compared to cell populations exposed solely to cyclic stretch. We have also measured significant differences in both cell death and cell detachment rates in cell monolayers experiencing combination of stresses. This research describes new tools for studying the combined effects of fluid mechanical and solid mechanical stress on alveolar cells. It also highlights the role that surface tension forces may play in the development of clinical pathology, especially under conditions of surfactant dysfunction. The results support the need for further research and improved understanding on techniques to reduce and eliminate fluid stresses in clinical settings. 相似文献
84.
Yousuke Yamada Dr. Mariko Kitajima Dr. Noriyuki Kogure Dr. Sumphan Wongseripipatana Prof. Dr. Hiromitsu Takayama 《化学:亚洲杂志》2011,6(1):166-173
Seven new indole alkaloids were isolated from the roots of Gelsemium elegans Benth. and their structures were determined by spectroscopic analysis and chemical transformation from known alkaloids. Kounaminal ( 1 ) is a new koumine‐type alkaloid that contains an unusual aminal moiety. Humantenoxenine ( 2 ) and 15‐hydroxyhumantenoxenine ( 3 ) are humantenine‐type alkaloids that contain a novel β‐amino‐α,β‐unsaturated ketone residue. The other four novel alkaloids are two gelsedilam‐related and two gelsenicine‐related alkaloids. 相似文献
85.
This paper reports the summary of experiments performed to successive generate small-scale underwater shock waves by means
of shock-induced collapse of microbubbles confined in a narrow gap. The project is motivated to develop a method for efficient
inactivation of marine bacteria contained in ship ballast water by high impulsive pressure loading. The shock wave–air bubbles
interaction was visualized by shadowgraph; the images were recorded by ImaCon200, and simultaneous pressure measurements were
performed by using an optical fiber pressure transducer with higher temporal resolution. Attaching small air bubbles on a
single nylon fiber and placing it in a confined space, we demonstrated sequential generation of impulsive high pressures at
the successive collapses of small bubbles at incident and reflected shock loadings. The values of the very short impulsive
pressures that occurred repeatedly for a relatively long term are found high enough to inactivate marine bacteria. 相似文献
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Free energies g(m, ms) and f(m, q) of the spherical spin glass (SG) model due to Kosterlitz et al. are calculated explicitly as functions of the uniform magnetization m, and SG order parameter ms and the Edwards-Anderson order parameter q. It is shown that g(0, ms) and f(0, q) below the transition temperature Tg are constant in the ranges 0 ≦ ms ≦ ms0 and 0 ≦ q ≦ q0 respectively, where . The proper equilibrium values of ms( = ms0) and q( d=q0) are then fixed from the inspection of their behaviors under infinitesimal uniform field proproportional to N-a(). 相似文献