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21.
We reported a case of unilateral gustatory disturbance produced by a lesion in the contralateral midbrain. A 37-year-old man first noticed dysesthesia in the left side of his face. Later, the patient developed dysesthesia of the left part of the lip, muscular weakness on the left lower extremity and gustatory disturbance on the left side. MR scan disclosed a lesion in the tegmentum of the right midbrain, which showed low intensity on a T1-weighted image and high intensity on a T2-weighted image. This lesion could be due to multiple sclerosis. This case suggests that the unilateral gustatory information ascends via the contralateral pathway at the midbrain level. It is suggested that the central gustatory pathways above the ipsilateral pontine taste are ascend via the contralateral projections to the thalamic taste area (parvicellular portion of the ventral posteromedial thalamic nucleus, VPMpc).  相似文献   
22.
BACKGROUND: The purpose of this investigation was to identify and characterize abdominal lymphomas as they occur in a large solid-organ-transplant population. METHODS: A large transplant population was isolated, and all patients developing an abdominal lymphoma were identified. These patients were further characterized after review of their medical records and radiologic examinations. RESULTS: Twenty-eight (1%) of 2925 patients developed lymphoma following transplantation. Of these 28 patients, 14 developed abdominal manifestations of disease. Examples of the wide variety of abdominal manifestations of posttransplant lymphoma are presented. Most of these patients had positive titers for Epstein-Barr virus and were treated with cyclosporin as a part of their immunotherapy. The majority of patients died secondary to this aggressive disease process. CONCLUSION: The development of lymphoma following solid organ transplantation is more common than in the general population. One-half of the patients in our study population developed abdominal manifestations of this disease.  相似文献   
23.
Abstract

In this paper, the fracture problem of an axisymmetric crack in a functionally graded thermal barrier coating (FGTBC) bonded to a homogeneous substrate is considered. The problem is solved for the laminate that is suddenly heated from the upper surface of the FGTBC. The bottom surface of the homogeneous substrate is maintained at the initial temperature. The crack faces are supposed to be completely insulated. Material properties are assumed to be exponentially dependent on the distance from the interface. By using both the Laplace and Hankel transforms, the thermo-mechanical fracture problem is reduced to a singular integral equation and a system of singular integral equations which are solved numerically. The stress intensity factors of the crack are computed and presented as functions of the normalized time for various values of the nonhomogeneous and geometric parameters.  相似文献   
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25.
An improved thinning method for density tapering of planar array antennas   总被引:1,自引:0,他引:1  
A thinning method is presented to realize the desired aperture distribution in a planar array antenna with elements fixed on an array lattice. In this method elements to be excited are determined by quantizing cumulative weights which are calculated from the desired aperture distribution. At first, this method is applied to density tapering on orthogonal axes of a planar array. Radiation patterns of the planar array determined by this method are compared with those by the desired amplitude distribution, and the results show good coincidence. Next, this method is extended to density tapering on four axes, that is, orthogonal and diagonal axes of a planar array. Moreover, this method is applied to density tapering with multi-amplitude level elements in order to enhance directive gain of thinned array. Lastly, a rectangular planar array was fabricated, and its radiation patterns were measured. Measured results were in good coincidence with calculated ones, and the usefulness of this method was verified.  相似文献   
26.
This paper deals with the vibration of open cylindrical shells by the spline strip method based on Novozhilov's shell theory. Convergence of the solutions is investigated in a few examples and is found to be satisfactory. The accuracy of the results is compared with those calculated by other numerical methods and found to be in good agreement. The effect of inlcuded angles and inplane constraints on vibrating characteristics of simply supported cylindrical shells is shown.  相似文献   
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28.
An elastic limit load of skew plates is analyzed on the basis of the Rayleigh-Ritz method with B-spline functions and the Huber-Mises yield criterion. Dimensionless elastic limit loads, associated maximum deflections and the positions of the first yield points are presented for different skew angles, aspect ratios and boundary conditions.  相似文献   
29.
Effects of ifenprodil tartrate, a potent vasodilator, on the autonomic, peripheral and central nerve system were studied in experimental animals. In isolated vas deferens of guinea pigs, the contraction in response to noradrenaline and sympathetic nerve stimulation was competetively antagonized by ifenprodil 10(-7)--10(-5) M (pA2: 7.69 against noradrenaline). Ifenprodil (50 approximately 1,000 mug/kg i.v.) inhibited the contraction of cat nictitating membrane and dog urinary bladder induced by sympathetic nerve stimulation. Ifenprodil (250 approximately 1,000 mug/kg i.v.) lowered adrenaline-induced lethality (ED50: 360 mug/kg). The drug produced a hypermotility of guinea pig uterus, and showed a transient hypertonus of dog gut which was abolished by atropine. Ifenprodil (10 approximately 20 mg/kg i.v.) inhibited the propulsion of charcoal meal in mice. In Shay rats, more than 10 mg/kg i.m. of the drug inhibited the secretion of acid gastric juice and the ulceration. Ifenprodil showed a potent local anesthetic action in the guinea pig cornea and skin. The spontaneous EEG of rabbits showed a resting pattern (0.25 approximately 2 mg/kg i.v.) followed by an arousal pattern (5 approximately 10 mg/kg). Ifenprodil (20 approximately 100 mg/kg p.o.) potentiated a hypnosis induced by barbital, and potentiated pentylenetetrazol, strychnine and picrotoxin induced convulsion. The drug (20 and 100 mg/kg p.o.) lowered the body temperature of rats. From these results it is concluded that ifenprodil produces a blocking action of alpha-adrenoceptors in various smooth muscle preparations and a direct relaxation of the smooth muscle itself without affecting the motor and central nerve systems.  相似文献   
30.
A new type of holographic antenna based on the principle of the volume hologram is proposed. The characteristics of the prototype are examined. The antenna has a unidirectional beam with a front-to-back ratio of 20 dB. The practical frequency handwidth is about 10 percent of the center frequency. The antenna is unique in that the feed point is placed in the plane of the holographic plate so that both feeder and the holographic plate could be made out of one printed circuit board for easy flush mount installation or mass production, although the feeder of the prototype antenna was a pyramidal horn.  相似文献   
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