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991.
992.
AA van Baardwijk ME Verhaegh GA Krekels AH Vermeulen HA Neumann 《Canadian Metallurgical Quarterly》1997,141(11):524-529
OBJECTIVE: Evaluation of Mohs' micrographic surgery as treatment for recurrent basal cell carcinoma of the skin. DESIGN: Retrospective. SETTING: University Hospital Maastricht, the Netherlands. METHOD: In the period April 1992 to December 1995, 91 recurrent basal cell carcinomas (88 patients) were treated by Mohs' micrographic surgery. Medical records were analysed retrospectively with respect to different aspects. RESULTS: The mean age of the patients was 69 years. The recurrent basal cell carcinomas, with an mean diameter of 19.7 mm, were mainly localized on the nose and forehead. There were equal numbers of solid and morphea-like types of basal cell carcinomas. Most of these tumours had been treated by means of surgical excision in the past. The last treatment had taken place 3 years previously on average. Reconstruction was performed by means of primary closure, a graft or a flap. The mean follow-up period after Mohs' micrographic surgery was 12 months, in which one tumour recurred. CONCLUSION: Mohs' micrographic surgery is a surgical technique which provides the best prospect of total tumour removal together with maximal functional and cosmetic preservation. Mohs' micrographic surgery is of particular value for the treatment of recurrent basal cell carcinomas. 相似文献
993.
MC Gilfillan PJ Noel ER Podack SL Reiner CB Thompson 《Canadian Metallurgical Quarterly》1998,160(5):2180-2187
Costimulation was originally defined and characterized during primary T cell activation. The signaling events that regulate subsequent antigen encounters by T cells are less well defined. In this study we examined the role of CD30 in T cell activation and defined factors that regulate expression of CD30 on T cells. We demonstrate that CD30 expression is restricted to activated T cells and regulated by CD28 signal transduction. In contrast to CD28-expressing TCR Tg cells, CD28-deficient TCR Tg cells did not express CD30 when cultured with peptide and APCs. However, rIL-4 reconstituted CD30 expression on CD28-deficient TCR Tg cells. Blockade of CD28 interactions or depletion of IL-4 inhibited the induction of CD30, suggesting that both CD28 and IL-4 play important roles in the induction of CD30 expression on wild-type cells. However, CD28 signaling did not up-regulate CD30 expression solely through its ability to augment IL-4 production because IL-4-deficient T cells stimulated with anti-CD3 and anti-CD28 expressed CD30. Induction of CD30 in the absence of IL-4 was not due to the IL-4-related cytokine IL-13. CD30, when expressed on an activated T cell, can act as a signal transducing receptor that enhances the proliferation of T cells responding to CD3 crosslinking. Collectively, the data suggest that T cell expression of CD30 is dependent on the presence of CD28 costimulatory signals or exogenous IL-4 during primary T cell activation. Once expressed on the cell surface, CD30 can serve as a positive regulator of mature T cell function. 相似文献
994.
H. Grassmann G. -M. Greuel B. Martin W. Neumann G. Pfister W. Pohl H. Schönemann T. Siebert 《Applicable Algebra in Engineering, Communication and Computing》1996,7(3):235-249
We describe an implementation of a general standard basis algorithm, valid for any monomial ordering compatible with the natural semigroup structure. We concentrate on new strategies which have proved useful, in particular in the non-wellordering case. Moreover, we describe the first implementation of Schreyer's method to compute syzygies and compare it with other, more classical methods. Comparisons of the computing time of several examples in the system SINGULAR give hints as to which strategies should be used in different classes of examples. 相似文献
995.
The main feature separating a living pacemaker from other oscillators is the fact that the former has not only the oscillatory property but also slow and fast changes of the membrane potential corresponding to the sub- and suprathreshold regions. We propose a simple mathematical model called mRIC and show that the model exhibited the essential feature of pacemakers generating spikes at constant time intervals. The behavior of the model driven by periodic pulse trains is analysed using the phase transition curve. 相似文献
996.
997.
Estrogen/progestin hormone replacement therapy in menopausal women has 2 important medical rationales. First of all, patients are relieved from the subjective symptoms almost fully. In addition patients benefit from prophylaxis of long term even life threatening sequelae of estrogen deficiency. This paper documents the results of a multicenter phase IV study, performed nationwide in Austria with 158 participating gynaecologists. Objective of this phase IV study was the analysis of efficacy and safety data of a new estrogen/progestin hormone replacement therapy scheme under almost practice conditions in the gynaecological context. The therapy supplied was Premarin plus, containing 28 coated tablets of 0.625 or 1.25 mg conjugated estrogens and in addition 12 tablets for the last cycle days containing 5 mg medrogeston. Thus, the dispensing gynaecologists had the option of an individual estrogen dose adjustment in case the low starting dose showed lack of efficacy. The results are based on the data of 1508 recruited female patients. A very high degree of representativeness is attributable to the high number of recruited patients. Overall judgement of the results shows a very high level of efficacy and a well tolerated scheme of hormone replacement therapy with the option of individual estrogen dose adjustments. 相似文献
998.
Nghiem S.V. Li F.K. Shu-Hsiang Lou Neumann G. McIntosh R.E. Carson S.C. Carswell J.R. Walsh E.J. Donelan M.A. Drennan W.M. 《Geoscience and Remote Sensing, IEEE Transactions on》1995,33(3):708-721
Ocean radar backscatter in the presence of large waves is investigated using data acquired with the Jet Propulsion Laboratory NUSCAT radar at Ku band for horizontal and vertical polarizations and the University of Massachusetts C-SCAT radar at C band for vertical polarization during the Surface Wave Dynamics Experiment. Off-nadir backscatter data of ocean surfaces were obtained in the presence of large waves with significant wave height up to 5.6 m. In moderate-wind cases, effects of large waves are not detectable within the measurement uncertainty and no noticeable correlation between backscatter coefficients and wave height is found. Under high-wave light-wind conditions, backscatter is enhanced significantly at large incidence angles,with a weaker effect at small incidence angles. Backscatter coefficients in the wind speed range under consideration are compared with SASS-II (Ku band), CMOD3-H1 (C band), and Plant's model results which confirm the experimental observations. Variations of the friction velocity, which can give rise to the observed backscatter behaviors in the presence of large waves, are presented 相似文献
999.
1000.