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101.
Granisetron (G) is an effective antiemetic drug that is used to prevent cisplatin-induced emesis, although it is less effective for delayed emesis. To enhance the antiemetic effects of granisetron, corticosteroid analogues such as methylprednisolone (M) and dexamethasone (D) were employed in a study of patients treated with cisplatin (CDDP). We investigated the clinical response and urinary excretion of 5-hydroxyindole acetic acid (5-HIAA), the main metabolite of serotonin, in 31 patients with ovarian cancer or uterine endometrial cancer who received CAP therapy (CDDP 75 mg/m2) in a 3-day cross-over trial comparing G + M and G + D treated patients. Both regimens were and delayed emesis than G + D. We conclude that G + D is a more efficacious combination than G + D in protecting patients from CDDP-induced acute and delayed emesis.  相似文献   
102.
We conducted an experimental investigation of natural convection in an enclosure containing horizontal parallel heated plates. Our experimental setup was as follows: Two heated plates were arranged vertically in an enclosure. The temperature of the ceiling was maintained at a constant low temperature, while the other sides satisfied thermal insulation boundary conditions. We examined flow characteristics in the enclosure and heat transfer around the horizontal heated plates. In the region between the cooled ceiling and the upper heated surface, vortex motion occurred when the accompanying flow from the lower region interfered with the ascending flow. Heat transfer around the heated surface was enhanced by this vortex motion. In other regions, the flow circulated along the heated surfaces in all cases. Generally speaking, for each flow pattern, the Nusselt number was proportional to some power of the modified Rayleigh number.  相似文献   
103.
A new evaluation method for coking coals has been proposed for foundry coke manufacturing. The distribution of optical textures in coke was evaluated by an automatic image analysis system. Hydrogen donor and acceptor abilities of coals and pitch were also measured. The extent of the development of anisotropic texture in the coke correlates closely to hydrogen transfer ability of coal and pitch mixture. The hydrogen transfer ability in the raw material is one of the most important parameters for foundry coke manufacturing.  相似文献   
104.
A pacemaker was implanted into a 17-year-old man with cardiac failure due to complete atrioventricular block complicated by mitochondrial encephalomyopathy (Kearns-Sayre syndrome). Due to the possible complication of latent myocardial dysfunction, it was decided to implant the dual chamber pacemaker (DDD) and the operation mode was set to DDD 70 ppm 1 year after implantation; this alleviated the cardiac failure. In this case, the necessity of preventive pacemaker implantation in the early stage of cardiac failure was recognized.  相似文献   
105.
Presents a simple general and exact method for solving resonant tunneling problems in multilayered heterostructures. This method is based on the analogy of wave propagation between the transmission line and the potential structure. By using the proposed method, it is shown that electron wave propagation can be treated as wave propagation on an equivalent circuit and that various problems can be systematically solved by using well-developed circuit functions and circuit matrixes. In particular, our equivalent circuit can be effectively used for analysis of resonant interband tunneling (RIT) structures and resonant tunneling structures including Γ-X mixing by using the interface matrix. Various properties of the resonant tunneling structure and a guideline for designing new quantum effect devices can be easily obtained. In order to show the validity and usefulness of this method, some numerical examples of InAs-GaSb and GaAs-AlAs potential barrier structures are presented  相似文献   
106.
Ultimately low OH content optical fibres with 1.2% refractive-index difference and 80 ?m core diameter have been successfully obtained by dehydrating a v.a.d.-made porous preform under optimised conditions. The loss increase at 1.39 ?m due to residual OH ions was only 0.04 dB/km. Accordingly, the measured attenuation curve can be resolved into contribution from the intrinsic loss mechanism with the additional low waveguide imperfection loss.  相似文献   
107.
108.
A ridge-waveguide AlGaAs/GaAs multiquantum-well (MQW) laser has been monolithically integrated with two MESFETs on a semi-insulating GaAs substrate. The laser was grown in an etched groove to realise a nearly planar horizontal arrangement with FETs. This MQW laser was found to successfully achieve a CW operation with a lowthreshold current of 20 mA at room temperature.  相似文献   
109.
110.
This paper proposes a variable-speed wind generation system using an interior permanent-magnet synchronous generator (IPMSG). The armature current vector of the IPMSG is optimally controlled according to the generator speed in order to maximize the generated power from the wind turbine. The IPMSG is controlled by the loss-minimization control with maximum power point tracking below the base speed, which corresponds to low and medium wind speed, and the maximum energy can be captured from the wind. Above the base speed corresponding to the high wind speed region, the current- and voltage-limited maximum output control is applied, where the current vector is optimally controlled so that the output may become the maximum in consideration of the constraints of current and voltage. The proposed output maximization control is achieved without mechanical sensors such as wind speed sensor and position sensor. The control system has been developed and several experimental results show the effectiveness of the proposed wind generation system.  相似文献   
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