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Immunochemical studies on human monoclonal macroglobulins with specificities for 3,4-pyruvylated D-galactose and 4,6-pyruvylated D-glucose 总被引:4,自引:0,他引:4
A S Rao J Liao E A Kabat E F Osserman M Harboe W Nimmich 《The Journal of biological chemistry》1984,259(2):1018-1026
Four of six human monoclonal IgM proteins were found to react best with Klebsiella polysaccharides containing 3,4py beta DGal (pyruvic acetalated D-galactopyranose), one with Klebsiella polysaccharides with 4,6pyDGlc; the sixth is uncharacterized. The combining sites of two of these (IgMWEA and IgMNAE) were essentially indistinguishable by quantitative precipitin studies at varying pH and by quantitative precipitin inhibition assays, but the other two differed in specificity of their combining sites from these and from each other. These differences were detected by precipitin inhibition assays with 3,4py beta DGal-containing oligosaccharide alditols, the R and S isomers of methyl 4,6py alpha DGal, the R isomer of methyl 4,6py beta DGal, or the R and S isomers of methyl 4,6py alpha DGlc, and -beta DGlc. In all of these except the S isomer of methyl 4,6pyDGal and R isomer of methyl 4,6pyDGlc, the carboxyl group is axial to the plane of the acetal ring. Their specificity appears to be determined by the nonreducing ends of chains and is considered to be cavity-type. 相似文献
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Summary Using an aeroscope, airborne fungal spores were sampled for two years, 1987–1988 at Tiruchirapalli, Tamil Nadu, India. The aerospora components, their seasonal and annual variations in incidence in the air are discussed and a spore calendar for Tiruchirapalli is presented. 相似文献
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A double-blind controlled trial in 24 lepromatous leprosy patients in reaction showed that clofazimine (Lamprene) controlled symptoms of erythema nodosum leprosum reaction in lepromatous leprosy better than prednisolone. Clofazimine also appeared to be significantly superior in preventing recurrence once the reaction had been controlled. There was a statistically significant rise in serum albumin among inpatients on clofazimine as compared with patients on prednisolone, but no difference in terms of neurological status, bacterial index, morphological index, and renal functions. Red/black hyperpigmentation was seen among practically all patients on clofazimine. No other side-effects or deleterious systemic effects were observed. 相似文献
25.
Summary Studies on the effect of different levels of sucrose in the slurry of peat-based Rhizobium inoculant on germination, seedling growth, and rhizosphere fungi of peanut and soybean revealed that the limits of tolerance for good germination were 2.5 and 5 per cent of the sugar, respectively. Fusaria and aspergilli were invariably present at all levels of sucrose whereas species of Penicillium, Myrothecium, Cunninghamella and Curvularia were isolated only from the rhizosphere at higher levels of the sugar 相似文献
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Several types of NS cells were identified in Portunus sanguinolentus--five types (A, A', B, C and D) in the brain and thoracic ganglion, four types (A, B, C and D) in the commissural ganglia and four types (alpha, beta, gamma and delta) in the optic ganglia. The distribution of these NS cells is described. Cytochemically, the neurosecretory material in the NS cells has a carbohydrate moiety and is rich in disulphide groups, lipids, phospholipids and RNA. It contains a small amount of sulphydryl groups and protein-bound NH2 groups, but no tyrosine or tryptophan. The NS activity of the brain was found to be closely associated with the reproductive and moult cycles. Just before the initiation of vitellogenesis and moulting the NS cells display secretory hyperactivity. Axonal transport of NS material was also observed in the NS cells. 相似文献
29.
Michael Jae-Yoon Chung Abram L. Friesen Dieter Fox Andrew N. Meltzoff Rajesh P. N. Rao 《PloS one》2015,10(11)
A fundamental challenge in robotics today is building robots that can learn new skills by observing humans and imitating human actions. We propose a new Bayesian approach to robotic learning by imitation inspired by the developmental hypothesis that children use self-experience to bootstrap the process of intention recognition and goal-based imitation. Our approach allows an autonomous agent to: (i) learn probabilistic models of actions through self-discovery and experience, (ii) utilize these learned models for inferring the goals of human actions, and (iii) perform goal-based imitation for robotic learning and human-robot collaboration. Such an approach allows a robot to leverage its increasing repertoire of learned behaviors to interpret increasingly complex human actions and use the inferred goals for imitation, even when the robot has very different actuators from humans. We demonstrate our approach using two different scenarios: (i) a simulated robot that learns human-like gaze following behavior, and (ii) a robot that learns to imitate human actions in a tabletop organization task. In both cases, the agent learns a probabilistic model of its own actions, and uses this model for goal inference and goal-based imitation. We also show that the robotic agent can use its probabilistic model to seek human assistance when it recognizes that its inferred actions are too uncertain, risky, or impossible to perform, thereby opening the door to human-robot collaboration. 相似文献
30.
Paolo d’Errico Marina Boido Antonio Piras Valeria Valsecchi Elena De Amicis Denise Locatelli Silvia Capra Francesco Vagni Alessandro Vercelli Giorgio Battaglia 《PloS one》2013,8(12)
Loss of the survival motor neuron gene (SMN1) is responsible for spinal muscular atrophy (SMA), the most common inherited cause of infant mortality. Even though the SMA phenotype is traditionally considered as related to spinal motor neuron loss, it remains debated whether the specific targeting of motor neurons could represent the best therapeutic option for the disease. We here investigated, using stereological quantification methods, the spinal cord and cerebral motor cortex of ∆7 SMA mice during development, to verify extent and selectivity of motor neuron loss. We found progressive post-natal loss of spinal motor neurons, already at pre-symptomatic stages, and a higher vulnerability of motor neurons innervating proximal and axial muscles. Larger motor neurons decreased in the course of disease, either for selective loss or specific developmental impairment. We also found a selective reduction of layer V pyramidal neurons associated with layer V gliosis in the cerebral motor cortex. Our data indicate that in the ∆7 SMA model SMN loss is critical for the spinal cord, particularly for specific motor neuron pools. Neuronal loss, however, is not selective for lower motor neurons. These data further suggest that SMA pathogenesis is likely more complex than previously anticipated. The better knowledge of SMA models might be instrumental in shaping better therapeutic options for affected patients. 相似文献