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141.
M Huttova I Hartmanova K Kralinsky J Filka J Uher J Kurak S Krizan V Krcmery 《Canadian Metallurgical Quarterly》1998,17(11):1012-1015
PURPOSE OF THE STUDY: To assess efficacy and safety of fluconazole in neonates with Candida fungemia. STUDY DESIGN: Multicenter prospective protocol of all fungemias appearing between January 1, 1993, and December 31, 1997, in four major university hospitals. RESULTS: Forty neonates, 28 of them with very low birth weight (<1500 g; 30.5 median gestation week), with documented Candida albicans fungemia were treated with intravenous fluconazole in a daily dosage of 6 mg/kg once daily for 6 to 48 days. Thirty-four received fluconazole as monotherapy and 6 received it in combination with amphotericin B. Thirty-two (80%) were cured; 4 of them relapsed despite at least 14 days of therapy, but they were ultimately cured without sequelae. Eight other neonates died, 4 because of fungal infection and 4 because of prematurity or hemorrhage or lung failure, with fungemia (20% overall and 10% attributable mortality). Two neonates had elevated liver enzymes during fluconazole therapy and 2 others had elevated serum creatinine during fluconazole monotherapy. In none of them did these abnormalities necessitate discontinuation of antifungal therapy. In 8 neonates fungal meningitis developed as a complication of fungemia. All but 3 fungemias were C. albicans; 3 were Candida parapsilosis. CONCLUSIONS: Fluconazole was safe and effective antifungal therapy even in complicated or Candida fungemia in neonates and in infants with very low birth weight. 相似文献
142.
Ku T.K. Chen S.H. Yang C.D. She N.J. Wang C.C. Chen C.F. Hsieh I.J. Cheng H.C. 《Electron Device Letters, IEEE》1996,17(5):208-210
Undoped and phosphorus (P)-doped diamond-clad Si field emitter arrays have been successfully fabricated using microwave plasma chemical vapor deposition (MPCVD) technology. The electron emission from the blunt diamond-clad microtips are much higher than those for the pure Si tips with sharp curvature due to a lower work function. Furthermore, the characteristics of emission current against applied voltage for the P-doped diamond-clad tips show superior emission at lower field to the undoped ones. After the examination of Auger electron spectroscopy (AES) and electrical characteristics of as-grown diamond, such a significant enhancement of the electron emission from the P-doped diamond-clad tips is attributed to a higher electron conductivity and defect densities 相似文献
143.
This paper proposes a sensorless speed measurement scheme that improves the performance of transducerless induction machine drives, especially for low-frequency operation. Speed-related harmonics that arise from rotor slotting and eccentricity are analyzed using digital signal processing. These current harmonics exist at any nonzero speed and are independent of time-varying parameters, such as stator winding resistance. A spectral estimation technique combines multiple current harmonics to determine the rotor speed with more accuracy and less sensitivity to noise than analog filtering methods or the fast Fourier transform. An on-line initialization routine determines machine-specific parameters required for slot harmonic calculations. This speed detector, which has been verified at frequencies as low as 1 Hz, can provide robust, parameter-independent information for parameter tuning or as an input to a sensorless flux observer for a field-oriented drive. The performance of the algorithm is demonstrated over a wide range of inverter frequencies and load conditions 相似文献
144.
The calculations of the first paper suggesting phase separation in the Hubbard model [2] are performed under modern computer facilties for the one and three-band Hubbard model. High-temperature approximations for specific heat and static correlation functions are obtained. The latter show, at these high temperatures, no tendency to phase separate in the same way as in the cited paper because our spin parallel nearest-neighbor charge correlation function is negative for all doping values. The spin antiparallel correlation function has positive and negative values for different doping regimes.Extension of this work to higher levels of iterations and to other correlation functions is in progress. 相似文献
145.
Pharmacodynamic Comparison of a Nasal Formulation of Verapamil and Intravenous and Oral Dosage Forms
The nasal route has been shown to be effective for the administration of numerous drugs in order to improve drug bioavailability. A nasal gel of verapamil hydrochloride was formulated and evaluated pharmacodynamically in humans, using electrocardiographic results, with comparison to oral and IV routes. Seven volunteers were involved in the study and the pharmacodynamic parameters were evaluated statistically. Experimental nasal gel showed similar pharmacodynamic results with the intravenous route, which is a hint to the reduction in verapamilinduced first-pass metabolism. However, oral route of administration showed a tendency of less efficacy. No reasonable effect of verapamil could be obtained with the placebo group. 相似文献
146.
Tsukude M. Arimoto K. Hidaka H. Konishi Y. Hayashikoshi M. Suma K. Fujishima K. 《Design & Test of Computers, IEEE》1993,10(2):6-12
Two testing techniques for ultra-large-scale integrated (ULSI) memories containing on-chip voltage downconverters (VDCs) are described. The first in an on-chip VDC tuning technique that adjusts internal VCC to compensate for the monitored characteristics of the process parameters during repair analysis testing. The second is an operating-voltage margin test, performed at various internal VCC levels during the water sort test (WT) and the final shipping test (FT) 相似文献
147.
N. Balchev D. Kovacheva V. Lovchinov K. Konstantinov K. Petrov 《Journal of Superconductivity》1993,6(1):49-54
The preparation conditions, phase composition, and superconducting properties of Bi-Pb-Sr-Ca-Cu oxide materials from different nominal compositions have been investigated. Nearly single-phase samples from Bi2Pb0.4Sr2Ca3Cu4O
y
, as well as from the proposed compositions Bi1.8Pb0.4Sr2Ca3Cu4O
y
and Bi1.8Pb0.4Sr2Ca2.5Cu3.5O
y
were obtained by a solid-state reaction in air. Samples with the third nominal composition showed the best superconducting properties (T
on=111 K and zero resistance atT
0=103 K). A possible mechanism for the 2223 phase formation in the three investigated compositions has been discussed. 相似文献
148.
This paper discusses changes in the spectrum and distortion of the electron wave function of a GaAs quantum well when a thin
AlGaAs barrier is introduced into it. The potential difference generated across the quantum well by distortion of the electron
wave function is calculated, along with its dependence on the position of the barrier in the quantum well. The photovoltaic
response of the structure to optical intersubband excitations is also calculated, along with the role of wave function and
electronic spectrum distortion as well as intersubband nonradiative transitions in generating this response. The suitability
of a GaAs quantum well with a thin barrier for use as an infrared detector is considered.
Fiz. Tekh. Poluprovodn. 32, 1246–1250 (October 1998) 相似文献
149.
K Fortini 《Canadian Metallurgical Quarterly》1997,117(9):667-669
The use of body mediated therapies at the Clinical geriatric psychiatry became possible due to the convergence between multi, inter and transdisciplinary approaches and the clinical experience in this application of various therapeutic technics. This approach at the aged clinic must take into consideration the specificity of the correlation to the body of the aged person beside the advantages and the needs that resent this approaches to both the patient and his therapist. 相似文献
150.
As shown previously for two-dimensional geometries, anisotropy effects should not be ignored in electrical impedance tomography (EIT) and structural information is important for the reconstruction of anisotropic conductivities. Here, we describe the static reconstruction of an anisotropic conductivity distribution for the more realistic three-dimensional (3-D) case. Boundaries between different conductivity regions are anatomically constrained using magnetic resonance imaging (MRI) data. The values of the conductivities are then determined using gradient-type-algorithms in a nonlinear-indirect approach. At each iteration, the forward problem is solved by the finite element method. The approach is used to reconstruct the 3-D conductivity profile of a canine torso. Both computational performance and simulated reconstruction results are presented together with a detailed study on the sensitivity of the prediction error with respect to different parameters. In particular, the use of an intracavity catheter to better extract interior conductivities is demonstrated 相似文献