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41.
Histamine and prostaglandins (PGs) play a variety of physiological roles as autacoids, which function in the vicinity of their sources and maintain local homeostasis in the body. They stimulate target cells by acting on their specific receptors, which are coupled to trimeric G proteins. For the precise understanding of the physiological roles of histamine and PGs, it is necessary to clarify the molecular mechanisms involved in their synthesis as well as their receptor-mediated responses. We cloned the cDNAs for mouse L-histidine decarboxylase (HDC) and 6 mouse prostanoid receptors (4 PGE(2) receptors, PGF receptor, and PGI receptor). We then characterized the expression patterns and functions of these genes. Furthermore, we established gene-targeted mouse strains for HDC and PG receptors to explore the novel pathophysiological roles of histamine and PGs. We have here summarized our research, which should contribute to progress in the molecular biology of HDC and PG receptors.  相似文献   
42.
Electronic apparatus in partially opened metal boxes often malfunctions due to electrostatically induced voltage. The induced voltage (induced potential difference, IPD) produces when charged bodies exist and move close. Objectives of this study are (1) to improve the voltage level capable of measuring an induced voltage, (2) to discriminate its polarity. In this study, the IPD and its polarity are demonstrated by means of a neon lamp and a photomultiplier tube. The results will be useful to estimate the value and polarity of the IPD as well as to help with the basic design of printed circuit boards.  相似文献   
43.
The purpose of this paper was to investigate the feasibility of a newly developed hyperspectral fundus imaging camera with a liquid crystal tunable filter. The intensities of different wavelengths of light transmitted through an artery, vein, and the area surrounding these vessels and reflected out were measured, and the differential spectral absorptions were analyzed. Measurements were made from 16 normal eyes and from two artificial capillaries. The ratios of absorption (ROA) of arteries to veins from 500 to 580 nm (range 1) and from 600 to 720 nm (range 2) were calculated. For all eyes, the ROArange1 was larger than ROArange2. The ROA obtained from the artificial capillary filled with blood saturated with oxygen or nitrogen was similar to that of simulated data of oxy- and deoxyhemoglobin extinction rate. Most ROAs of human eyes were lower than those of the simulated data and the artificial capillaries. Oxygen saturation analysis by hyperspectral fundus imaging of retinal vessels were qualitatively in agreement with thein vitro analysis or simulated values. However, further improvements are necessary to evaluate the oxygen saturation quantitatively in the retinal blood vessels.  相似文献   
44.
In this paper we give an explicit formula for level 1 vertex operators related to as operators on the Fock spaces. We derive also their commutation relations. As an application we calculate with the vector representation of , thereby extending the recent work on the staggered polarization of the XXZ-model.  相似文献   
45.
We present results for nu(mu) oscillation in the KEK to Kamioka (K2K) long-baseline neutrino oscillation experiment. K2K uses an accelerator-produced nu(mu) beam with a mean energy of 1.3 GeV directed at the Super-Kamiokande detector. We observed the energy-dependent disappearance of nu(mu), which we presume have oscillated to nu(tau). The probability that we would observe these results if there is no neutrino oscillation is 0.0050% (4.0 sigma).  相似文献   
46.
Abstract

A variety of cyclic and acyclic ethers are efficiently reacted with acyl chlorides or acyl bromides to afford the ether-cleaved compounds of ω-chloro-or ω-bromoesters under high pressure conditions. The reactivity of ethers is found to be roughly depend on the basicity of the ether oxygen atom.  相似文献   
47.
Electric quadrupole coupling constant eqQ/h of the extremely proton-rich 23Al (I π ?=?5/2?+?, T 1/2?=?0.47 s) nucleus implanted into an Al2O3 single crystal has been measured for the first time, using the β-ray detecting nuclear quadrupole resonance method (β-NQR) in a high magnetic field. As a preliminary result, the quadrupole coupling constant was determined as |eqQ/h(23Al) |?=?2.66±0.77 MHz. Using the quadrupole coupling constant of 27Al in Al2O3 as a reference, the Q moment of the ground state of 23Al was extracted as |Q(23Al)|?~?160 mb, which is well explained by the shell model calculation in the sd-shell model space with the USD interaction.  相似文献   
48.
The diffusion coefficients of Li in the NaTl-type Li intermetallic compound of β-LiGa have been measured by using a short-lived radioactive diffusion tracer. As the tracer, the α-emitting radioisotope of 8Li delivered as the energetic and pulsed beam from Tokai Radioactive Ion Accelerator Complex (TRIAC) was implanted into the β-LiGa compounds with the composition in the range of about 43 to 54 at.% Li. By analyzing the time-dependent yields of the α-particles measured according to the repetition cycle of the beam, the tracer diffusion coefficients were extracted over the wide range of Li composition. Abnormal composition-dependence of Li diffusion coefficients in β-LiGa was observed; the stoichiometric β-LiGa showed the highest diffusivity of Li. By referring to the composition-dependent diffusivity of Li in the iso-structural β-LiAl and β-LiIn, we could identify the abnormal diffusion of Li in very Li-poor composition of β-LiGa. The anomaly has been discussed qualitatively in terms of the formation of defect complex and the interaction between the constitutional defects.  相似文献   
49.
We investigate numerically complex dynamical systems where a fixed point is surrounded by a disk or ball of quasi-periodic orbits, where there is a change of variables (or conjugacy) that converts the system into a linear map. We compute this “linearization” (or conjugacy) from knowledge of a single quasi-periodic trajectory. In our computations of rotation rates of the almost periodic orbits and Fourier coefficients of the conjugacy, we only use knowledge of a trajectory, and we do not assume knowledge of the explicit form of a dynamical system. This problem is called the Babylonian problem: determining the characteristics of a quasi-periodic set from a trajectory. Our computation of rotation rates and Fourier coefficients depends on the very high speed of our computational method “the weighted Birkhoff average”.  相似文献   
50.
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