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71.
The prognosis of aggressive non-Hodgkin's lymphoma (NHL) has improved greatly during recent years with the use of combination chemotherapy. Planning the treatment must take into consideration the patient's age, performance status, histological subtype and disease extent and severity. Recently, a 4-part International Prognostic Index (IPI), based on 5 prognostic factors, has permitted the allocation of patients with NHL in 2 well defined prognostic groups: good prognosis (low and low-intermediate risk) and poor prognosis (intermediate-high and high risk). Conventional chemotherapy with CHOP (a chemotherapeutic regimen consisting of a combination of cyclophosphamide, doxorubicin, vincristine and prednisone) or other equivalent third-generation regimens may be considered the standard treatment for the good prognosis group. In the poor prognosis group the probability of long term survival is less than 40% with conventional chemotherapy. Therefore, an early intensification with high dose therapy following peripheral stem cell transplantation (PSCT) should be considered in the setting of randomised trials. Localised stage disease, defined as stages I-IE and II-IIE without adverse prognostic factors, has a very good prognosis with a long term survival exceeding 80% using brief conventional chemotherapy regimens plus involved field radiotherapy. Refractory or relapsing patients after the drugs of first choice are given who subsequently respond to salvage chemotherapy should be enrolled for a course of high dose consolidation chemotherapy followed by PSCT. Elderly patients without severe organ dysfunction can take advantage from specifically devised chemotherapy regimens, with a response rate similar to that of younger patients. However, despite major advances in the treatment of aggressive NHL, additional clinical trials are required to enable the clinician to define the best therapeutic programmes to treat patients with this disorder.  相似文献   
72.
In this paper, we propose a local projection stabilization (LPS) finite element method applied to numerically solve natural convection problems. This method replaces the projection-stabilized structure of standard LPS methods by an interpolation-stabilized structure, which only acts on the high frequencies components of the flow. This approach gives rise to a method which may be cast in the variational multi-scale framework, and constitutes a low-cost, accurate solver (of optimal error order) for incompressible flows, despite being only weakly consistent. Numerical simulations and results for the buoyancy-driven airflow in a square cavity with differentially heated side walls at high Rayleigh numbers (up to \(Ra=10^7\)) are given and compared with benchmark solutions. Good accuracy is obtained with relatively coarse grids.  相似文献   
73.
Various realizations of variational multiscale (VMS) methods for simulating turbulent incompressible flows have been proposed in the past fifteen years. All of these realizations obey the basic principles of VMS methods: they are based on the variational formulation of the incompressible Navier–Stokes equations and the scale separation is defined by projections. However, apart from these common basic features, the various VMS methods look quite different. In this review, the derivation of the different VMS methods is presented in some detail and their relation among each other and also to other discretizations is discussed. Another emphasis consists in giving an overview about known results from the numerical analysis of the VMS methods. A few results are presented in detail to highlight the used mathematical tools. Furthermore, the literature presenting numerical studies with the VMS methods is surveyed and the obtained results are summarized.  相似文献   
74.
Summary The essential oil obtained by steam distillation of gentian roots (Gentiana lutea L.,Gentianaceae family) - a plant well know for its pharmacological properties and employed in the food industry, especially in making liqueurs - was investigated. The oil, after separation into fractions on a silica gel column, was investigated by GLC and GLC/MS. Limonene (34.68%), linalool, carvacrol, cis-linalyl oxide and aterpineol were the main components of the oil, totalling 50.04%. Several other minor components have been identified and are listed.
Ungewöhnliche etherische Öle mit aromatischen Eigenschaften III. Flüchtige Aromastoffe der Enzianwurzeln
Zusammenfassung Es wurde etherisches Öl analysiert, das durch Wasserdampfdestillation aus Enzianwurzeln (Gentiana lutea L.,Gentianaceae) gewonnen wurde. Die Pflanze ist aufgrund ihrer pharmakologischen Eigenschaften bekannt und wird auch in der Lebensmittelindustrie verwendet, ganz besonders für die Likör-und Magenbitterherstellung. Das Öl wurde durch Säulenchromatographie an Kieselgel mittels GLC und GC/MS analysiert. Limonen (34,68%), Linalool, Carvacrol,cis-Linalyloxid und -Terpineol bilden 50,04% des Öls. Darüber hinaus wurden weitere Bestandteile identifiziert.
  相似文献   
75.
Modelling the mechanical effect of muscles is important in several research and clinical contexts. However, few studies have investigated the effect of different muscle discretizations from a mechanical standpoint. The present study evaluated the errors of a reduced discretization of the lower-limb muscles in reproducing the muscle loading transferred to bones. Skeletal geometries and a muscle data collection were derived from clinical images and dissection studies of two cadaver specimens. The guidelines of a general method previously proposed for a different anatomical district were followed. The data collection was used to calculate the mechanical effect of muscles, i.e. the generalized force vectors, and the errors between a large and a reduced discretization, in a reference skeletal pose and in the extreme poses of the range of motion of joints. The results showed that the errors committed using a reduced representation of muscles could be significant and higher than those reported for a different anatomical region. In particular, the calculated errors were found to be dependent on the individual anatomy and on the skeletal pose. Since different biomechanical applications may require different discretization levels, care is suggested in identifying the number of muscle lines of action to be used in musculoskeletal models.  相似文献   
76.
意大利著名设计师Stefano Giovannoni不久前将一个旧工厂的厂房改建成居家与办公相结合的空间。项目的地点在米兰ViaTortona区附近。改建完成之后,由于其在建筑与室内设计上的特殊性,这个房子几乎成了展览及各类活动的举办地,尤其是salone国际设计周期间,这里更是热闹非凡。  相似文献   
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79.
A new strategy to prevent the biofouling of water-submerged surfaces is presented here. In particular, the authors showthat carbonic anydrase from Methanosarcina thermophila can be entrapped into polyacrylic paints, preserving enzyme activity. In addition, the authors also show that enzyme-containing paints inhibit the growth of marine microorganims, preventing biofouling.  相似文献   
80.
In the past few years detection of repeatable and distinctive keypoints on 3D surfaces has been the focus of intense research activity, due on the one hand to the increasing diffusion of low-cost 3D sensors, on the other to the growing importance of applications such as 3D shape retrieval and 3D object recognition. This work aims at contributing to the maturity of this field by a thorough evaluation of several recent 3D keypoint detectors. A categorization of existing methods in two classes, that allows for highlighting their common traits, is proposed, so as to abstract all algorithms to two general structures. Moreover, a comprehensive experimental evaluation is carried out in terms of repeatability, distinctiveness and computational efficiency, based on a vast data corpus characterized by nuisances such as noise, clutter, occlusions and viewpoint changes.  相似文献   
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