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This study was conducted to examine if central amiloride-sensitive transport systems are involved in the development and/or maintenance of hypertension in spontaneously hypertensive rats (SHR). Either amiloride (75 microg/60 microl/day) or artificial cerebrospinal fluid (aCSF, 60 microl/day) was infused centrally (i.c.v.) for 4 weeks to development (4-5-weeks-old) and maintenance (10-12-weeks-old) phases of hypertension in SHR. In development phase, amiloride i.c.v. (n=14) blunted the elevation of blood pressure (BP) compared to aCSF i.c.v. (n=9) (amiloride vs. aCSF; after 3 weeks of i.c.v., 146+/-3 vs. 166+/-5 mmHg, P

We examined the incidence of long P wave duration in lead II and increased P terminal force in lead V1 (PTFV1), and their relationship to electrophysiological findings of atrial muscle in 34 patients with sick sinus syndrome (SSS). Patients were divided into three groups: Group I, consisting of 20 patients with various cardiac arrhythmias other than SSS and paroxysmal atrial fibrillation (PAF) who served as controls; Group II, consisting of 18 patients with SSS but without PAF; and Group III consisted of 16 patients with SSS and PAF. P wave duration was significantly longer in Group III (122 +/- 11 ms, mean +/- SD, P < 0.0001) and Group II (111 +/- 15 ms, P < 0.002) than in Group I (98 +/- 10 ms). PTFV1 was greater in Group III (0.052 +/- 0.025 ms) than in Group I (0.028 +/- 0.011 ms, P < 0.05). P wave duration and PTFV1 had significantly and/or borderline correlations with longest duration of right atrial electrograms (r = 0.84, P < 0.0001 and 0.47, P < 0.02, respectively), maximal number of fragmented deflections of atrial electrograms (r = 0.69, P < 0.0001 and r = 0.51, P < 0.02, respectively), repetitive atrial firing zone (RAFZ) (r = 0.81, P < 0.0001 and 0.48, P < 0.05, respectively) and fragmented atrial activity zone (FAAZ)(r = 0.53, P < 0.01 and r = 0.45, P = 0.06, respectively). We concluded that long P wave duration and increased PTFV1 are electrocardiographic indicators for coexistence of electrophysiological abnormalities in the atria in SSS without recognizable heart disease.

A prototype of bispectral passive imaging system designed for the diagnosis of machine systems from their noises is presented. The principle is generalized aiming machine‐system diagnosis and the concrete construction of scanner of a microphone and the details of the signal processings as well as the obtained images are shown. Typical characteristics of the system are as follows: (a) images to be reconstructed, spatial distribution of the degree of interference among three frequency components or spatial distribution of intensity of noises emitted from the object; (b) maximum resolution, 15/f cm where f is the used frequency (f=0.5∠10 kHz); (c) time required to obtain one image, from 30 to 90 min depending on the number of sampling points; (d) display of result, print out on a typewriter or colored display on a TV monitor.

A new ultrasonic and/or acoustical imaging system, which uses non-Gaussian random signals and cross- and auto-bispectral analysis is presented in this paper. It consists of a fixed point receiver on a hologram plane and a scanning receiver on the same plane. The non-Gaussian signals radiated from the object and detected by these receivers are analyzed. By calculating their cross- and autobispectra and taking the ratio between them the holographic information, that is the distribution of the amplitudes and phases of a certain wave length is derived from these results over the plane. The following points will be presented; i) principle, ii) theoretical developments, iii) computer simulations and the outline of a prototype of a practical system for the diagnosis of machine system at audio frequency region. Mechanical noises, such. as the noises from engines of a submarine, can be regarded as non-Gaussian signals and ambiguous noises surrounding circumstances, such as the ocean tide, may be regarded as Gaussian noises, so this method is especially effective when it is used under fairly large additive Gaussian noises. Because bispectrum of Gaussian noises vanishes completely they do not disturb the hologram when it is obtained by the bispectral analysis. Although the fundamental parts of this method have been submitted in various journals (Refs. 1, and 2), comprehensive discussions will be given in this article.

Conception d'un systeme integre de conception et fabrication assistees ne necessitant pas un gros ordinateur