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51.
Maitrot A Lucas MF Doncarli C Farina D 《Medical & biological engineering & computing》2005,43(4):487-492
In the study, an efficient method to perform supervised classification of surface electromyogram (EMG) signals is proposed.
The method is based on the choice of a relevant representation space and its optimisation with respect to a training set.
As EMG signals are the summation of compact-support waveforms (the motor unit action potentials), a natural tool for their
representation is the discrete dyadic wavelet transform. The feature space was thus built from the marginals of a discrete
wavelet decomposition. The mother wavelet was designed to minimise the probability of classification error estimated on the
learning set (supervised classification). As a representative example, the method was applied to simulate surface EMG signals
generated by motor units with different degrees of short-term synchronisation. The proposed approach was able to distinguish
surface EMG signals with degrees of synchronisation that differed by 10%, with a misclassification rate of 8%. The performance
of a spectral-based classification (error rate approximately 33%) and of the classification with Daubechies wavelet (21%)
was significantly poorer than with the proposed wavelet optimisation. The method can be used for a number of different application
fields of surface EMG classification, as the feature space is adapted to the characteristics of the signal that discriminate
between classes.
An erratum to this article is available at . 相似文献
52.
McRobert SP Tompkins L Barr NB Bradner J Lucas D Rattigan DM Tannous AF 《Behavior genetics》2003,33(3):347-356
Many aspects of the reproductive behavior of Drosophila melanogaster are modified dramatically by experience and age. Males' courtship of immature males and fertilized females decreases over time. Females' receptivity to copulation, and the behaviors that females perform and elicit, are affected by their age and sexual experience. We show that mutations in a raised stock affect all of these age- and experience-dependent aspects of male and female sexual behavior. Experience has no effect on raised males' courtship of immature males and has opposite effects on raised and wild-type males' courtship of fertilized females. In comparison to controls, raised females become sexually mature at an earlier age, and sexually mature raised virgin females copulate more quickly. Following mating, raised females elicit more courtship and remate faster and more frequently than control females. 相似文献
53.
Frei K Szuhai K Lucas T Weipoltshammer K Schöfer C Ramsebner R Baumgartner WD Raap AK Bittner R Wachtler FJ Kirschhofer K 《European journal of human genetics : EJHG》2002,10(7):427-432
Mutations in the connexin 26 (Cx26) gene (GJB2) are associated with autosomal nonsyndromic sensorineural hearing loss. This study describes mutations in the Cx26 gene in cases of familial and sporadic hearing loss (HL) by gene sequencing and identifies the allelic frequency of the most common mutation leading to HL (35delG) in the population of eastern Austria. For this purpose we have developed and applied a molecular beacon based real-time mutation detection assay. Mutation frequencies in the Cx26 gene of individuals from affected families (14 out of 46) and sporadic cases (11 out of 40) were 30.4% and 27.5%, respectively. In addition to known disease related alterations, a novel mutation 262 G-->T (A88S) was also identified. 35delG accounted for almost 77% of all Cx26 mutations detected and displayed an allelic frequency in the normal hearing population of 1.7% (2 out of 120). The high prevalence of the 35delG mutation in eastern Austria would therefore allow screening of individuals and family members with Cx26 dependent deafness by a highly specific and semi-automated method. 相似文献
54.
Allen M Pratscher B Krepler C Frei K Schöfer C Pehamberger H Müller M Lucas T 《International journal of immunogenetics》2005,32(6):375-378
Two novel interleukin-24 (IL-24) splice variants were identified in normal human melanocytes by sequencing cloned polymerase chain reaction (PCR) products that are not expressed in metastatic melanoma. These gene products have been generated by differential skipping of exons 3 (IL-24 delE3) and 5 (IL-24 delE5). IL-24 delE3 has limited sequence identity to the IL-24-interacting protein mda-7s, and IL-24 delE5 is homologous to IL-24. 相似文献
55.
Aging and the Immune Response to the Haemophilus influenzae Type b Capsular Polysaccharide: Retention of the Dominant Idiotype and Antibody Function in the Elderly
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Anti-Haemophilus influenzae b polysaccharide (Hib PS) antibodies elicited in elderly subjects following conjugate vaccination expressed a light-chain variable-region (VL)-associated idiotype and had functional activities similar to those previously observed in children and younger adults. These findings indicate that advanced age is not accompanied by shifts in the major VL component of the Hib PS-specific repertoire or by diminution of the protective function of antibodies. 相似文献
56.
A fucose-containing epitope potentially involved in gamete interaction on the human zona pellucida 总被引:2,自引:1,他引:2
Lucas H.; Bercegeay S.; Pendu J.Le; Jean M.; Mirallie S.; Barriere P. 《Human reproduction (Oxford, England)》1994,9(8):1532-1538
The oligosaccharide moiety of human, porcine and bovine zonaepellucidae was studied with lectins and monoclonal antibodiesspecific for tri- or tetra-saccharidic epitopes containing atleast one terminal -L-fucose. Animal eggs were collected fromfollicular aspirates, human eggs were collected from in-vitrofertilization and embryo transfer programmes and pooled intosix groups. By direct immunofluorescence, the lectins reactivitywas detected for the animal or the human zonae pools in thesame way. Reactivity of Aleuria aurantia lectin demonstratedthe presence of L-fucose terminal residues in the zonaefrom the three species studied. By indirect immunofluorescence,the 225 antibody reactivity was detected in every poolof human zonae whereas there was no evidence of any antibodyreactivity on animal zonae. Using an anti-Lewis-b blood groupantibody (225), we observed expression of this antigenas an intrinsic component of the human zona pellucida, independentlyof patients'Lewis red blood cell phenotypes. Antibody 225inhibited the spermatozoa-zona binding in a hemizonaassay, suggesting that this fucose-containing antigen couldbe part of a sperm-zona receptor. 相似文献
57.
H M Dockrell S K Young K Britton P J Brennan B Rivoire M F Waters S B Lucas F Shahid M Dojki T J Chiang Q Ehsan K P McAdam R Hussain 《Infection and immunity》1996,64(10):4385-4389
Twelve mycobacterial antigens were compared for induction of gamma interferon (IFN-gamma) secretion by human blood mononuclear cells of patients with leprosy. Fractionated Mycobacterium leprae antigens containing cell wall proteins or cytosolic and membrane proteins induced good IFN-gamma responses in tuberculoid leprosy patients. Lipoarabinomannan from M. tuberculosis Erdman and M. leprae mycolylarabinogalactan peptidoglycan were the poorest IFN-gamma inducers. 相似文献
58.
Cold-adapted vaccine strains of influenza A virus act as dominant negative mutants in mixed infections with wild-type influenza A virus 总被引:2,自引:0,他引:2
The cold-adapted reassortant of influenza A, which is a candidate live virus vaccine, interfered with the replication of parental wild-type virus in mixed infections of either MDCK cells or embryonated eggs. The interference occurred at either the permissive or nonpermissive temperature for the cold-adapted virus. In doubly infected cells, the yield of the wild-type virus was reduced by as much as 3000-fold and the protein synthesis phenotype expressed was that of the cold-adapted virus. The interference was detected even when infection with wild-type virus was carried out at a 9-fold excess or 2 hr before infection with the cold-adapted virus. As well as interfering with its wild-type parental virus, the cold-adapted virus also inhibited the replication of a heterologous influenza A subtype. In addition to its immunogenic potential, the ability to interfere with the replication of wild-type viruses is a desirable trait for any live, attenuated virus vaccine. 相似文献
59.
Correlation of proliferation of lung epithelium with intramuscular sensitization and complement-fixing antibody to respiratory syncytial virus in the golden hamster.
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H V Ratajczak D O Lucas L M Kelley S E Wilson 《Clinical and experimental immunology》1981,45(3):595-603
Intramuscular sensitization of hamsters with several forms of respiratory syncytial virus (RSv) caused proliferation of lung epithelium. In contrast, intranasal injection of live virus rarely resulted in this phenomenon. A correlation existed between proliferation of lung epithelium and presence of complement-fixing antibody, but not between lung disease and delayed skin reactions. Complement-fixing antibody to RSv was found to be independent of the influence of the thymus. 相似文献
60.
Anfossi N Lucas M Diefenbach A Bühring HJ Raulet D Tomasello E Vivier E 《European journal of immunology》2003,33(12):3514-3522
A common feature of hematopoietic activating immunoreceptors resides in their association at the cell surface with transmembrane signaling adaptors. Several adaptors, such as the CD3 molecules, FcRgamma and KARAP/DAP12, harbor intracytoplasmic immunoreceptor tyrosine-based activation motifs (ITAM) that activate Syk-family protein tyrosine kinases. In contrast, another transmembrane adaptor, DAP10, bears a YxxM motif that delivers signals by activation of lipid kinase pathways. We show here that the human signal-regulatory protein SIRPbeta1 can associate with both DAP10 and KARAP/DAP12 in a model of RBL-2H3 cell transfectants. In association with KARAP/DAP12, SIRPbeta1 complexes are capable of inducing serotonin release and tumor necrosis factor (TNF) secretion. By contrast,in the absence of KARAP/DAP12, engagement of SIRPbeta1:DAP10 complexes does not lead to detectable serotonin release or TNF secretion by RBL-2H3 transfectants. However, triggering of SIRPbeta1:DAP10 complexes co-stimulates RBL-2H3 effector function induced by sub-optimal stimulation of the endogenous FcepsilonRI complex. Therefore, we report here a cellular model in which the association of a cell surface receptor with various signaling adaptors dictates the co-stimulatory or the direct stimulatory properties of the complex. 相似文献