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Streptococcus pneumoniae remains an important cause of disease with high mortality and morbidity, especially in children and in the elderly. The widespread use of the polysaccharide conjugate vaccines in some countries has led to a significant decrease in invasive disease caused by vaccine serotypes, but an increase in disease caused by non-vaccine serotypes has impacted on the overall efficacy of these vaccines on pneumococcal disease. The obvious solution to overcome such shortcomings would be the development of new formulations that provide serotype-independent immunity. This review focuses on the most promising approaches, including protein antigens, whole cell pneumococcal vaccines, and recombinant bacteria expressing pneumococcal antigens. The protective capacity of these vaccine candidates against the different stages of pneumococcal infection, including colonization, mucosal disease, and invasive disease in animal models is reviewed. Some of the human trials that have already been performed or that are currently ongoing are presented. Finally, the feasibility and the possible shortcomings of these candidates in relation to an ideal vaccine against pneumococcal infections are discussed.  相似文献   
134.
Quay crane and yard truck scheduling are two important subproblems in container terminal operations which have been studied separately in previous research. This paper proposes a new problem for the integrated quay crane and yard truck scheduling for inbound containers. The problem is formulated as a mixed integer programming (MIP) model. Due to the intractability, a genetic algorithm (GA) and a modified Johnson's Rule-based heuristic algorithm (MJRHA) are used for the problem solution. In addition, two closed form lower bounds are given to evaluate the solution accuracy. Computational experiments show that the solution algorithm can efficiently handle the scheduling problem and that the integrated methods are very useful.  相似文献   
135.
A model is developed for convex-set valued data,which are the Minkowski sum of aconvex parameter set and a convex noise set.This model is generalized to include location and scaleparameters.A further generalization results in a model for convex sets which is analogous to aone-way analysis of variance models.In each case,estimators of the parameters are given which,under certain conditions,are shown to be consistent.Data generated from the model and theestimators are studied.An outlier detection method is examined.  相似文献   
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137.
Countercurrent chromatography meets MS   总被引:1,自引:0,他引:1  
Y W Lee  R D Voyksner 《Nature》1989,338(6210):91-92
Interfacing countercurrent chromatography with thermospray mass spectrometry provides a new analytical tool for detecting nonvolatile, hydrophilic or thermally unstable bioactive natural products.  相似文献   
138.
v-Src and EJ Ras alleviate repression of c-Jun by a cell-specific inhibitor   总被引:17,自引:0,他引:17  
V R Baichwal  A Park  R Tjian 《Nature》1991,352(6331):165-168
  相似文献   
139.
B R Talamo  R Rudel  K S Kosik  V M Lee  S Neff  L Adelman  J S Kauer 《Nature》1989,337(6209):736-739
Alzheimer's disease is a central nervous system disorder characterized by the presence of neurofibrillary tangles, neuritic plaques and dystrophic neurites in susceptible areas of the brain. Investigation of the mechanism and development of the disease has been hampered by the lack of an animal model and the inaccessibility of neural tissue during the illness. Deficits in odour detection and discrimination are among the signs of Alzheimer's and previous anatomical studies suggest that olfactory pathways may be involved early in the illness. Neurons in the olfactory epithelium, which are of central origin, are relatively accessible for biopsy and could be used as a source of living nerve cells for the study of Alzheimer's disease if they can be shown to have characteristics of this disease. As these neurons have the unusual property of arising from stem cells throughout the life of the organism, they are good candidates for the development of cell cultures or cell lines which may express the disorder from living patients. We report here that nasal epithelium tissue taken at autopsy shows unique pathological changes in morphology, distribution and immunoreactivity of neuronal structures in patients with Alzheimer's disease.  相似文献   
140.
CD43, a molecule defective in Wiskott-Aldrich syndrome, binds ICAM-1.   总被引:12,自引:0,他引:12  
THE protein CD43 (also known as sialophorin, leukosialin, large sialoglycoprotein or gp115) is expressed on the surface of T lymphocytes, monocytes, neutrophils, platelets and some B lymphocytes. Expression of CD43 is deficient and/or defective in the X-chromosome-linked immunodeficiency disorder Wiscott-Aldrich syndrome, suggesting that CD43 might have a role in T-cell activation. We have shown that expression of human CD43 in an HLA-DR-specific murine T-cell hybridoma enhances the antigen-specific response to stimulation by the human lymphoblastoid cell line Daudi, and that Daudi cells bind specifically to purified immobilized CD43. These data indicate that the specific interaction of CD43 with a ligand on the surface of Daudi cells might contribute to T-cell activation. Here we report evidence that intercellular adhesion molecule-1 (ICAM-1, or CD54), is a ligand for CD43.  相似文献   
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