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71.
Heart transplant patients take several medications that could affect their periodontal health. Gingival overgrowth associated with cyclosporin (immunosuppressant agent) and nifedipine (calcium channel blocker) is well documented. Candidal infections often develop because of immune suppression. This report describes the clinical and histopathological changes in the gingival tissues of a heart transplant patient and their management. The gingival tissues exhibited pronounced enlargement. The gingivae were lobulated, and the surface of the lobulations was pebbly and granular. Biopsies showed lobules of fibrous connective tissue covered by stratified squamous epithelium. The outer surfaces were dotted with numerous smaller papillations. Candidal hyphae were present in the superficial layers of the epithelium. The extensive papillary lesions appear to be related to candidiasis and constitute a condition which is best designated as papillary stomatitis. Hyperplastic gingival tissues were excised, and the patient was placed on periodic maintenance. One-year postoperative follow-up showed minor gingival growth. 相似文献
72.
We report a case of early Wegener's disease mimicking tuberculosis in a 36 year old man. Lungs are solely affected for 6 months. Unusual appearance of radiographic features with large apical excavations explain the delai for the diagnosis. We discuss morphological features in the lungs and kidney. 相似文献
73.
Characterization of the epidermal growth factor receptor in pig oviduct and endometrium 总被引:1,自引:0,他引:1
K Wollenhaupt U Tiemann R Einspanier F Schneider W Kanitz KP Brüssow 《Canadian Metallurgical Quarterly》1997,111(2):173-181
Two different plaque variants of Japanese encephalitis virus were selected from a wild-type Taiwanese isolate using Vero cells. One variant was found to exhibit small plaque morphology with retarded virus replication kinetics in Vero cells, and was demonstrated to be resistant to monoclonal antibody (mAb) E3.3 neutralization. The other variant showed large plaque morphology, was sensitive to mAb E3.3 neutralization, and manifested reduced virulence in mice on both intracranial and intraperitoneal inoculations. These two variants propagated in Vero cells retained high levels of infectivity but had relatively low HA titers as compared with the parent strain. The envelope sequences of these two variants showed four amino acid differences at residues E-85 (Glu/Arg), E-306 (Glu/Gly), E-331 (Ser/Arg), and E-387 (Met/Arg). Our results indicated the neutralizing epitope of Japanese encephalitis virus did not overlap with virus virulence determinant. 相似文献
74.
Summary The laminar flow near an infinite plane wall perpendicular to a line sink of constant strength is investigated in the limit of large Reynolds numbers. Self-similarity requires that fluid is issuing from the boundary layer. The inviscid flow outside the boundary layer is governed by the Euler equations. A one-parametric set of solutions to the Euler equations with appropriate boundary conditions is given. Uniqueness of the inviscid flow solution is obtained from matching with the boundary layer expansion. The solution of the boundary-layer equations is given both in closed form and numerically. It is found that at the edge of the boundary layer the vorticity decays algebraically.Dedicated to Prof. Dr. Dr. h. c. Franz Ziegler on the occasion of his 60th birthday 相似文献
75.
Tony Maillet Jacques Barbier Jr. Daniel Duprez 《Applied catalysis. B, Environmental》1996,9(1-4):251-266
A 1% Pd catalyst (38% dispersion) was prepared by impregnating a γ-alumina with palladium acetylacetonate dissolved in acetone. The behaviour of this catalyst in oxidation and steam reforming (SR) of propane was investigated. Temperature-programmed reactions of C3H8 with O2 or with O2 + H2O were carried out with different stoichiometric ratios S(S =[O2]/5[C3H8]). The conversion profiles of C3H8 for the reaction carried out in substoichiometry of O2 (S < 1) showed two discrete domains of conversion: oxidation at temperatures below 350°C and SR at temperatures above 350°C. The presence of steam in the inlet gases is not necessary for SR to occur: there is sufficient water produced in the oxidation to form H2 and carbon oxides by this reaction. Contrary to what was observed with Pt, an apparent deactivation between 310 and 385°C could be observed with Pd in oxidation. This is due to a reduction of PdOx into Pd0, which is much less active than the oxide in propane oxidation. Steam added to the reactants inhibits oxidation while it prevents the reduction of PdOx into Pd0. Compared to Pt and to Rh, Pd has a higher thermal resistance: no deactivation occurred after treatment up to 700°C and limited deactivation after treatment up to 900°C, provided that the catalyst is maintained in an oxygen-rich atmosphere during the cooling. 相似文献
76.
Microllular plastics are cellular polymers characterized by cell densities greater than 109 cells/cm3 and cells smaller than 10 μm. One of the critical steps in the continuous production of microcellular plastics is the promotion of high cell nucleation rates in a flowing polymer matrix. These high nucleation rates can be achieved by first forming a polymer/gas solution followed by rapidly decreasing the solubility of gas in the polymer. Since, in the processing range of interest, the gas solubility in the polymer decreases as the pressure decreases, a rapid pressure drop element, consisting of a nozzle, has been employed as a continuous microcellular nucleation device. In this paper, the effects of the pressure drop rate on the nucleation of cells and the cell density are discussed. The experimental results indicate that both the magnitude and the cell density are discussed. The experimental results indicate that both the magnitude and the rate of pressure drop play a strong role in microcellular processing. The pressure phenomenon affects the thermodynamic instability induced in the polymer/gas solution and the competition between cell nucleation and growth. 相似文献
77.
78.
79.
John P. Wikswo Jr. Nestor G. Sepulveda Yu Pei Ma W. Patrick Henry Daniel J. Staton Duane Crum 《Journal of Nondestructive Evaluation》1993,12(2):109-119
A SQUID magnetometer can be used to measure the magnetic field produced by flaws in a two-dimensional, conducting plate carrying a current. Identification of the flaw-induced magnetic field is difficult because of the large magnetic field associated with the edges of the plate and the current in the leads that connect the plate to the power supply. We have developed a technique by which the wire and edge fields can be cancelled prior to mapping the magnetic field. In this technique, a similar unflawed conducting sheet is placed adjacent to the flawed plate, with a connection between the sheet and the plate at one edge, and with the opposite edges of the sheet and of the plate connected to the two conductors of a coaxial cable. Thus, an applied current will flow along one conductor of the cable, across the cancelling sheet, cross into the flawed plate, return along the plate, and then return to the power supply along the other conductor of the coaxial cable. As a result of this geometry, there is no magnetic field from the lead-in wires because they are coaxial, and the magnetic field due to the edges of the plate is cancelled by the opposing magnetic field of the edges in the adjacent sheet. The extent of cancellation is determined primarily by the separation between the plate and the cancelling sheet, by the thickness of the plate, and by macroscopic inhomogeneities in their electrical conductivities. 相似文献
80.
Lott J.A. Schneider R.P. Jr Vawter G.A. Zolper J.C. Malloy K.J. 《Electronics letters》1993,29(4):328-329
The demonstration of the first visible resonant cavity light-emitting diodes (RCLEDs) is reported. The devices consist of an InAlGaP strained quantum well active region surrounded by AlAs/AlGaAs distributed Bragg reflectors. Linewidths from 0.9 mm (2.6 meV) to 45 nm (12.8 meV) were obtained by varying the cavity factor (Q).<> 相似文献