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1.
AM-1155 is a newly synthesized 6-fluoro-8-methoxy quinolone. We assessed its in vitro antimycobacterial activity using sparfloxacin (SPFX) and ofloxacin (OFLX) as comparison drugs. The MICs of these agents for various mycobacterial strains were determined by the agar dilution method with 7H11 medium. AM-1155 had lower MICs for 50 and 90% of tested strains of Mycobacterium kansasii, M. marinum, and M. fortuitum-M. chelonae complex than SPFX and OFLX, and the values for M. tuberculosis, M. scrofulaceum, and the M. avium-M. intracellulare complex were similar to those of SPFX and considerably lower than those of OFLX. In addition, the antimicrobial activity of AM-1155 against M. tuberculosis and M. intracellulare phagocytosed into murine peritoneal macrophages was compared with that of OFLX. AM-1155 (1 microgram/ml) inhibited the intracellular growth of both M. tuberculosis and M. intracellulare, whereas OFLX at the same concentration failed to show any such effect. Moreover, AM-1155 (10 micrograms/ml) exhibited a steady bactericidal action against M. tuberculosis, whereas OFLX at the same concentration had only a weak effect. AM-1155 (10 micrograms/ml) also inhibited the growth of M. intracellulare more effectively than OFLX.  相似文献   
2.
In order to determine whether or not IFN-gammaR is associated with regulatory mechanisms on human eosinophil function, we examined the expression of functional IFN-gammaR on human peripheral eosinophils. In this study, peripheral blood eosinophils were obtained from seven normal controls and 12 patients (bronchial asthma, n = 9, and hypereosinophilic syndrome (HES), n = 3), and the purity of eosinophils was 97.11 +/- 2.31%, n = 19. We first showed that anti-IFN-gammaR alpha-chain MoAb reacted with all tested eosinophils of both normal controls and patients by flow cytometry analysis. We also showed expression of mRNA for the alpha-chain of IFN-gammaR in all purified eosinophils of six individuals. Further, to characterize IFN-gammaR on eosinophils, we did binding experiments with 125I-IFN-gamma on purified peripheral eosinophils. The linear Scatchard plot indicated a single type of high-affinity binding sites (dissociation constant (Kd) = 3.89-4.95 x 10(-10) M, numbers of binding sites = 183-233/cell, n = 3). To determine whether IFN-gammaR on eosinophils is functional, we examined surface eosinophilic cationic protein (ECP) and CD69 induction after IFN-gammaR ligation with recombinant human IFN-gamma (rhIFN-gamma) on eosinophils by flow cytometry. rhIFN-gamma stimulation significantly induced both ECP and CD69 expression on the 2-18 h-cultured eosinophils in a dose-dependent manner. Further, the effects of rhIFN-gamma stimulation were significantly blocked by both a neutralizing anti-IFN-gamma MoAb and a blocking anti-IFN-gammaR MoAb. These results suggest that human peripheral eosinophils express functional IFN-gammaR.  相似文献   
3.
This paper describes frequency control techniques for cold start and channel recognition functions in coherent multichannel local area networks. A Z-cut quartz etalon can be used to stabilize the optical transmitter frequencies. The capture range and the influence of humidity on a Fabry-Perot etalon are discussed. The frequency deviation of the optical transmitter was estimated to be less than ±1 GHz in the long term. A double AFC loop has been proposed for local LD frequency control. It showed a wide capture range of ±100 GHz. Coherent FDM receiver switching to the desired channel was demonstrated over a range from 0 to 40°C in an experiment  相似文献   
4.
Four normal pancreas, 8 chronic pancreatitis specimens, and 30 non-endocrine pancreatic tumors from humans and 6 normal and 6 induced pancreatic cancers in hamsters were examined immunohistochemically by antibodies against human transforming growth factor-alpha (TGF-alpha) and epidermal growth factor receptor (EGFR). Two normal pancreas and two pancreatic cancer specimens from each species were also studied immunoelectron microscopically by the immunogold method. In chronic pancreatitis, the reactivity and intensity of the staining with both antibodies were much greater in ductal/ductular cells than in the normal pancreas. All 30 pancreatic cancers reacted with both antibodies with a variable degree of reactivity and staining intensity. No correlation was found between the histological type of tumors, the degree of tumor differentiation, and the incidence and patterns of reactivity of either antibody. Immunoelectron microscopically, both EGFR and TGF-alpha were demonstrated primarily on the basal membrane. In the normal hamster pancreas, TGF-alpha was overexpressed in the alpha-cells but not in any other islet cells. Both TGF-alpha and EGFR were marginally detectable in the exocrine pancreas and in induced pancreatic lesions. This is the first demonstration of subcellular localization of TGF-alpha and EGFR in the normal and diseased human and hamster pancreas.  相似文献   
5.
6.
A robust DC?CDC converter which can covers extensive load change and also input voltage changes with one controller is needed. Then the demand to suppress output voltage change becomes still severer. We propose an approximate 2-degree-of-freedom (2DOF) digital controller which realized start-up response and dynamic load response independently. The controller makes a control bandwidth wider, and at the same time makes variations of the output voltage small at sudden changes of a load and an input voltage. In this paper, a new approximate 2DOF digital control system with additional zeros is proposed. Using the additional zeros, the second-order differential transfer characteristics between equivalent disturbances and a output voltage are realized. Therefore, the new controller makes variations of the output voltage smaller and the sudden changes of the load and the input voltage. This controller is actually implement on a DSP and is connected to the DC?CDC converter. Experimental results demonstrate that this type of digital controller can satisfy given severe specifications with low frequency sampling.  相似文献   
7.
Metastable lath martensite ( L ) phase wires with high strengths have been produced in the Fe-Ni-Cr-Al-C alloy system by melt spinning in rotating water. These wires have a circular cross section and a white lustre and the wire diameter is in the range of 100 to 140m. The width and length of each lath in the L phase are as small as about 0.3 and 2m, respectively. The y, f and p are about 900 and 1650 MPa and 2.0% for the L wires. The subsequent annealing causes an increase in p as well as y and f and the attained values are about 1000 and 1700 MPa and 3.0% for Fe-10Ni-10Cr-6.5 Al-1.0C wire annealed at 773 K for 1 h owing to the precipitation strengthening of a very fine unidentified carbide and to a high density of dislocations and lath boundaries in the L phase. Further annealing causes a significant decrease in p through decomposition of L to+M7C3+M23C6. Therefore, the high strength combined with relatively good ductility for the L wires is interpreted as due to the suppression of the phase transformation of L to a mixed structure of+M7C3+M23C6 by melt quenching.  相似文献   
8.
A novel method has been developed for measuring direct compressive properties such as strength and elasticity of a series of mesophase-pitch-based and PAN-based carbon fibres about 10 m in diameter by uniaxial and transverse compression tests using a micromechanical tester. The fibres were shaped into cylindrical specimens, with their size ratio of length to diameter kept at about 2 to 3, by separating them from a thin film made by polishing the cut faces of a strand of carbon fibres with epoxy resin as a matrix. Individual cylindrical specimens were stood up or laid down on a glass plate without any fixer for the measurements of axial and transverse compression properties of fibres, respectively. The fibres exhibited non-linear elasticity, with the compressive modulus decreasing with compressive deformation. The direct axial compressive strengths of pitch-based carbon fibres were found to be marginally lower than the indirect ones, whereas there was no significant difference between the two strength values for PAN-based fibres. The pitch-based fibres exhibited smaller average values of axial compressive strength than the PAN-based fibres. The transverse compressive strength, which decreases with an increase in elasticity of carbon fibres, exhibited a considerably lower average value than that of the axial compressive strength. Further, the axial compressive strength was found to be smaller than the direct tensile strength for the fibres.  相似文献   
9.
Optical recording demands a meticulous write strategy to control the laser beam power and regulate the phase change layer temperature tightly. The width, height, and delay of a string of short pulses applied to the laser diode need to be adjusted in fine steps, and the writing speed varies widely per applications. A multi-phase phase-locked loop (PLL) tracks a wide range of clock frequencies, and provides a low-jitter time base for write pulses. With two enabling circuit concepts, PLL loop filter voltage folding/unfolding and switch-in of parallel MOS resistors in delay cells, it is possible to operate a PLL to cover a frequency range spanning over three octaves with one VCO. A 10-stage differential VCO is phase-locked to the input channel clock ranging from 26 to 420 MHz (1/spl times/-16/spl times/ DVD speed), and its 20-phase outputs are used to generate write pulses. The pulsewidth and delay are programmed with 120 /spl plusmn/ 40 ps time resolution. The prototype chip fabricated in 0.35 /spl mu/m CMOS occupies 3.5/spl times/3.3 mm/sup 2/, and consumes 294 mW at 3.3 V.  相似文献   
10.
In a software product management, it is an important problem to determine the optimal release timing which minimizes the total expected cost incurred in both testing and operation phases. In this paper, we compare the performance between two kinds of software release methods, which are referred to as the T-policy and the N-policy. Based on the existing software reliability growth models, we formulate the expected cost functions and derive analytically the optimal policies under these control methods. Also, we derive a criterion for which control methods should be adopted. Finally, in numerical examples, we calculate the optimal release policies for several cost parameters.  相似文献   
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