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71.
72.
Accelerated idioventricular rhythm was observed in three newborn infants with congenital heart disease. This ventricular arrhythmia in all of our patients did not alter the clinical features of the congenital heart disease, and it disappeared at the ages of 84 days, 40 days, and 45 days, respectively. This arrhythmia is generally considered to be benign, which also appears to be the case with the newborn infant with congenital heart disease.  相似文献   
73.
The postoperative outcomes in patients with hepatolithiasis are greatly affected by the presence of residual stones. One hundred and seventeen patients with hepatolithiasis treated in our clinic were analysed. The indication of hepatectomy for hepatolithiasis was determined by the degree of stricture of intrahepatic bile duct. The rate of residual stones was reduced from 54.5% to 14.5% by the introduction of choledochoscopical lithotomy. Thus, pre- and postoperative choledochoscopical examination and lithotomy are shown to play an important role in treatment of the patients with hepatolithiasis.  相似文献   
74.
Nowadays, a GHz frequency signal needs to be propagated on a printed circuit board (PCB) with low distortions. In addition, a higher-frequency signal of 10 GHz or more will also need to be propagated with low distortion in very-large-scale integration (VLSI) in the future. However, signal propagation with low distortion is getting more and more difficult as the frequency increases. In order to solve this problem and to ensure signal integrity, we have proposed a novel transmission line called a “segmental transmission line” (STL). In the STL, a transmission line is divided into multiple segments of individual characteristic impedance. The multiple segments are designed to fix the waveform distortion on the transmission line by solving a combinatorial explosion problem using a genetic algorithm. In a previous article, we have shown the effectiveness of an STL designed for a GHz clock signal in computer simulations. We have also fabricated two scaled-up STL prototypes for a clock signal using real printed circuit boards (PCBs). In this article, we input a random signal by changing its frequency to the scaled-up STL prototype designed for a 150-MHz clock signal. We show that the STL has high robustness to the random signals and the frequency fluctuations, which indicates the generality of the STL technique.  相似文献   
75.
The purpose of this study was to investigate long-term outcomes of Haemophilus influenzae Type b meningitis in a cohort of school-age survivors. Findings from an initial assessment at mean age 10 years revealed neuropsychological, achievement, and behavioral sequelae in the children with neurologic complications during the acute-phase illness (H. Taylor, C. Schatschneider, & D. Rich, 1992). Here, the cohort was reassessed 1 and 2 years after the initial evaluation to investigate age-related influences on disease sequelae. After excluding children with hearing loss, the sample was divided into 2 groups: an affected group of 39 children with acute-phase neurologic complications and an unaffected group of 73 children without these complications. Growth-curve modeling showed poorer outcomes at the final assessment and less rapid improvement at follow-up for the affected group. Later age at assessment and later age at illness were associated with larger group differences in some outcomes. Results suggest that children with diffuse early brain insults are at risk for later-emerging sequelae. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
76.
In order to conduct a detailed investigation of the piston effect, the peculiar heat transportation phenomenon in critical fluids, an ultra-sensitive high-speed density measurement system was developed using a very thin heater, a sensitive interferometer and a large-capacity high-speed data acquisition system. As the first step of the investigation, an experiment was conducted to measure the velocity of sound in CO2 near its critical point. Short heat pulses suppressing the disturbance of natural convection were applied to a small cell filled with almost-critical CO2 fluid and were detected by the measurement system. Because the pulses propagated through the cell at the velocity of sound and were reflected several times between the cell walls, the velocity could be precisely determined by measuring the time intervals between successive reflections. The resulting velocity profile versus temperature showed good agreement with theoretical prediction and numerical simulations. This result validated the density measurement system, and it is considered that the measurement system will be a very effective tool for further studies on critical phenomena with the aid of numerical simulation.  相似文献   
77.
The electron paramagnetic resonance (EPR, or electron spin resonance) method was used to measure CO??· radicals recorded in tooth enamel by exposure to atomic-bomb gamma rays. The EPR-estimated doses (i.e. ??Co gamma-ray equivalent dose) were generally in good correlation with cytogenetic data of the same survivors, whereas plots of EPR-estimated dose or cytogenetically estimated dose against DS02 doses turned out to scatter more widely. Because those survivors whose EPR doses were higher (or lower) than DS02 doses tended to show also higher (or lower) responses for cytogenetic responses, the apparent variation appears primarily due to problems in individual DS02 doses rather than the measurement errors associated with the EPR or cytogenetic technique. A part of the enamel samples were also used for evaluation of neutron doses by measuring ?1Ca/??Ca ratios using the accelerator mass spectrometry technique. The results for the measured ratios were on average ~85 % of the calculated ratios by DS02 (but within the 95 % confidence bounds of the simulated results), which lends support to DS02-derived neutron doses to the survivors.  相似文献   
78.
A memory array architecture and row decoding scheme for a 3 V only DINOR (divided bit line NOR) flash memory has been designed. A new sector organization realizes one word line driver per two word lines, which is conformable to tight word line pitch. A hierarchical negative voltage switching row decoder and a compact source line driver have been developed for 1 K byte sector erase without increasing the chip size. A bit-by-bit programming control and a low threshold voltage detection circuit provide a high speed random access time at low Vcc and a narrow program threshold voltage distribution. A 4 Mb DINOR flash memory test device was fabricated from 0.5 μm, double-layer metal, triple polysilicon, triple well CMOS process. The cell measures 1.8×1.6 μm2 and the chip measures 5.8×5.0 mm 2. The divided bit line structure realizes a small NOR type memory cell  相似文献   
79.
We report a case of an 82-year-old woman with polymyalgia rheumatica (PMR) associated with swelling and pitting edema of the lower extremities. The patient had been previously admitted because of PMR in 1990, but there was no history of swollen extremities. In July 1996, at another hospital, she was again diagnosed as having PMR on the basis of pain in the neck, shoulders and lower back. Administration of prednisolone was followed by improvement of the symptoms. Four months later, similar pain recurred and swelling of the lower extremities was noted. On admission, the erythrocyte sedimentation rate was 86 mm/h, and C-reactive protein was 15.5 mg/dl. Reviewing the previous treatment, it was ascertained that her clinical deterioration was due to premature reduction of the steroid dosage. The cause of the swelling of the lower extremities was unlikely to be heart, liver, kidney or endocrine disease. Prednisolone was increased from 2.5 mg to 10 mg daily with marked improvement in all the symptoms including the swelling and pitting edema. In 1996, a study reported distal extremity swelling with pitting edema as a manifestation of PMR, which mostly developed concurrently with proximal symptoms or during relapses of PMR. The swelling responded poorly to non-steroidal antiinflammatory drugs but promptly to corticosteroids. The distal swelling was reported to be tenosynovitis and synovitis of the surrounding structures. The present case appears similar to that report. More studies of PMR need to be done.  相似文献   
80.
We present an object-oriented open-source framework for solving the dynamics of open quantum systems written in Python. Arbitrary Hamiltonians, including time-dependent systems, may be built up from operators and states defined by a quantum object class, and then passed on to a choice of master equation or Monte Carlo solvers. We give an overview of the basic structure for the framework before detailing the numerical simulation of open system dynamics. Several examples are given to illustrate the build up to a complete calculation. Finally, we measure the performance of our library against that of current implementations. The framework described here is particularly well suited to the fields of quantum optics, superconducting circuit devices, nanomechanics, and trapped ions, while also being ideal for use in classroom instruction.Program summaryProgram title: QuTiP: The Quantum Toolbox in PythonCatalogue identifier: AEMB_v1_0Program summary URL: http://cpc.cs.qub.ac.uk/summaries/AEMB_v1_0.htmlProgram obtainable from: CPC Program Library, Queen?s University, Belfast, N. IrelandLicensing provisions: GNU General Public License, version 3No. of lines in distributed program, including test data, etc.: 16 482No. of bytes in distributed program, including test data, etc.: 213 438Distribution format: tar.gzProgramming language: PythonComputer: i386, x86-64Operating system: Linux, Mac OSX, WindowsRAM: 2+ GigabytesClassification: 7External routines: NumPy (http://numpy.scipy.org/), SciPy (http://www.scipy.org/), Matplotlib (http://matplotlib.sourceforge.net/)Nature of problem: Dynamics of open quantum systems.Solution method: Numerical solutions to Lindblad master equation or Monte Carlo wave function method.Restrictions: Problems must meet the criteria for using the master equation in Lindblad form.Running time: A few seconds up to several tens of minutes, depending on size of underlying Hilbert space.  相似文献   
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