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81.
An LSI-based user-network interface circuit, applicable to a network terminal (NT) for the integrated services digital network (ISDN) basic interface is developed. Adaptive timing extraction, with a simplified polyphase phase-locked oscillator, is introduced into the circuit for application to both point-to-point and passive bus configurations. This circuit does not require any manual adjustment. In addition to the primitives defined by CCITT between layers one and two, a new primitive is adopted for controlling the transmission of information. This primitive avoids premature transmission due to processing delays in the exchange terminal (ET). The above functions are fabricated on a CMOS gate-array LSI chip with 4000 gates. The performance of the interface circuit is confirmed with special attention to transmission and electrical characteristics  相似文献   
82.
This paper presents a set of rules for the transformation of GHC (Guarded Horn Clauses) programs based on unfolding. The proposed set of rules, called UR-set, is shown to preserve freedom from deadlock and to preserve the set of solutions to be derived. UR-set is expected to give a basis for various program transformations, especially partial evaluation of GHC programs.  相似文献   
83.
An 8-month-old cat with bilateral hindlimb paresis was admitted. Radiography revealed a curvature of the thoracic spine and a partial deformation of thoracolumbar vertebrae (dorsal extrusion of the cranial and caudal edges). Compression of the spinal cord (T9-L1 and L6-7) was found by myelography. Medicinal treatment did not yield the desired result. Hemilaminectomy and laminectomy were done to relieve pressure on the spinal cord leading to improved gait. It is, however, not clear whether this syndrome was primarily caused by metabolic or genetic factors.  相似文献   
84.
85.
Electron spin resonance (ESR) was used to study defects induced by 2MeV-proton irradiation in cubic silicon carbide (3C-SiC) epitaxially grown on Si substrates by chemical vapor deposition. A new ESR signal labeled T5 was observed at temperatures lower than ≈100 K in Al doped, p-type 3C-SiC epilayers irradiated. The T5 signal has anisotropic g-values of g1 = 2.0020 ± 0.0001, g2 = 2.0007 ± 0.0001,and g3 = 1.9951 ± 0.0001. The principal axes of the g-tensor were found to be along the 〈100〉 directions, indicating that the T5 center has D2 symmetry. Isochronal annealing of the irradiated epilayers showed that the T5 center was annealed at temperatures around 150° C. A tentative model is discussed for the T5 center.  相似文献   
86.
The present study was designed to determine the systemic haemodynamic effects of obliterating oesophageal varices by endoscopic sclerotherapy. We evaluated systemic and splanchnic haemodynamics before and after the first course of sclerotherapy in cirrhotic patients. The baseline cardiac index was significantly correlated with baseline azygos vein blood flow (r = 0.64; P < 0.01) and the azygos vein blood flow and cardiac index significantly decreased (-33% and -16%, respectively; P < 0.01) following sclerotherapy. The systemic vascular resistance index was also increased significantly (+ 20%; P < 0.01) in these patients. Moreover, the per cent change in azygos vein blood flow was directly correlated with that of the cardiac index (r = 0.51; P < 0.03). We conclude from these findings that the obliteration of portosystemic collaterals by sclerotherapy significantly reverses hyperdynamic circulation in such patients via a decrease in cardiac preload. The blood flow of the portosystemic shunt per se is a leading contributor to the hyperdynamic circulation observed in patients with well-developed portal systemic collateral vessels.  相似文献   
87.
88.
The heart of an open chest dog was stimulated by strong magnetic fields which were damped sinusoidal pulses with the one-cycle period of 1.47 ms. Stimulation effects were detected by electrocardiograph (ECG) and arterial blood pressure as a function of the strength of the field, the triggering point in the cardiac cycle, and the position of a stimulating coil. The threshold for arrhythmias was a minimum for the stimuli triggered at the apex of the T wave and on the P wave in the ECG. Premature ventricular and premature atrial contractions occurred according to whether the coil was placed over the ventricles or the atria. Ventricular defibrillation can not be attained by the magnetic stimulus with the flux density of 9.2 T which was the maximum field used  相似文献   
89.
The properties of the widely used TDX Analyzer and recently developed OPUS Immunoassay System were compared using 403 serum specimens taken from patients who did or did not take digoxin. Of the 210 specimens from patients not treated with digoxin, a false- positive digoxin concentration was detected in 15 specimens (7%) by TDX and in only 2 specimens (1%) by OPUS because of the cross-reactivity with structurally similar drugs. Potassium canrenoate, digitoxin, deslanoside, and methyldigoxin exhibited marked concentration-dependent cross-reactivity in the TDX assay method, whereas deslanoside and methyldigoxin only showed cross-reactivity with the antibody used in the OPUS method. Although a poor correlation was observed between these two methods for the determination of 193 samples from patients treated with digoxin, the correlation was remarkably improved (r = 0.914) and the slope approximated unity when excluded the data from patients who were treated concurrently with the cross-reactive compounds. In routine TDM of digoxin, the authors experienced two cases in which cross-reactivity of the assay system caused a clinical problem. Concurrent administration of intravenous canrenoate apparently interfered with the digoxin assay by TDX, but this problem was solved by using the OPUS system. The authors found OPUS more useful for monitoring serum digoxin concentrations in patients because of its superior specificity.  相似文献   
90.
Mitochondrial DNA (mtDNA) control regions from 40 Japanese wild boars were examined by direct sequencing after amplification by PCR. From the DNA sequences obtained, we found eight haplotypes, whose differences arose via transitions. The geographical distribution of these different haplotypes indicated that wild boar populations inhabited limited areas and that there was some restricted gene flow between local populations. Eight mtDNA haplotypes from Eastern and Western domestic pigs and the Ryukyu wild boar were also analyzed as references to those from Japanese wild boars. The cluster analyses of the control-region sequences showed that those from Japanese wild boars belong to the Asian type as do those from Eastern domestic pigs and the Ryukyu wild boar, which differed from the European type (Western domestic pigs).  相似文献   
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