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991.
We report the case of a 51-year-old woman with anosmia and chronic sensory ataxic neuropathy. Olfactory tests suggested neurosensory anosmia. Immunocytochemical analysis showed serum antibodies against dorsal root ganglion (DRG) cells and olfactory neurons, in the absence of other known causes of anosmia and sensory neuropathy. Clinical and laboratory data suggested a slow autoimmune process affecting dorsal root ganglion and olfactory cells.  相似文献   
992.
Corticosteroids treatment   总被引:3,自引:0,他引:3  
Corticosteroids (Cs) are widely used for treatment of multiple sclerosis (MS) acute relapses because of the potent immunosuppressive and anti-inflammatory properties. As for patients with relapsing-remitting (RR) MS, short-term administrations of Cs markedly less severity of symptoms and promote faster recovery of clinical attacks. Chronic administrations of Cs significantly diminish the formation of T1 hypointense lesions and the progression of brain atrophy. As for patients with secondary progressive MS treatment with Cs delays the time to onset of sustained disability. Finally the association between methylprednisolone and interferon beta (IFNbeta) leads the recovery of active lesions at greater extent and reduces the formation of neutralizing antibodies (NABs) against IFNbeta in patients with RRMS.  相似文献   
993.
994.
Action observation and speech production: study on children and adults   总被引:2,自引:0,他引:2  
The present study aimed to determine whether observation of upper limb actions selectively influences speech production. We compared the effects on children with those on adults, hypothesizing that action observation is used by children for speech learning. Children and adults observed an actor either grasping a cherry or an apple, or bringing the same fruits to his mouth. They pronounced the syllable/ba/ at the end of the action. In a control experiment, children and adults executed the two bringing-to-the-mouth actions, still pronouncing/ba/. As previously found ([Euro. J. Neurosci., 17 (2003) 179]; [Euro. J. Neurosci., 19 (2004) 192]), the observed kinematics of the action, which were different according to the fruit size, influenced lip shaping kinematics and voice formants. In addition, the effect was selective for the action since the observations of actions such as grasping and bringing-to-the-mouth affected formant 1 and formant 2 in the voice spectra, respectively. The effects on speech were greater in the children than in the adults. By contrast, the effects on lip shaping did not differ between the two groups. Effects similar to those found for action observation were found for action execution in spite of a different arm kinematics between children and adults. The results of the present study are discussed according to the hypothesis that action observation induces in the viewer action recognition and activation of the successive mouth act (probably grasping-with-the-mouth when observing grasping-with-the-hand and chewing when observing bringing-to-the-mouth). This subsequently seems to affect characteristics peculiar to the emitted vowel. This mechanism might have been used by humans to transfer a primitive arm gesture communication system from the arm to the mouth and may be further used by children for speech learning.  相似文献   
995.
Enriched environment and acceleration of visual system development   总被引:8,自引:0,他引:8  
Rearing mice from birth in an enriched environment leads to a conspicuous acceleration of visual system development appreciable at behavioral, electrophysiological and molecular level. Little is known about the possible mechanisms of action through which enriched environment affects visual system development. It has been suggested that differences in maternal behavior between enriched and non-enriched conditions could contribute to the earliest effects of enriched environment on visual development and that neurotrophins, BDNF in particular, might be involved. Here, we examined Brain Derived Neurotrophic Factor (BDNF) levels in the visual cortex during development and showed that an increase occurs in the first week of life in enriched pups compared to standard reared pups; BDNF levels at birth were equal in the two groups. This suggests a postnatal rather than a prenatal effect of environment on BDNF. A detailed analysis of maternal care behavior showed that pups raised in a condition of social and physical enrichment experienced higher levels of licking behavior and physical contact compared to standard reared pups and that enhanced levels of licking were also provided to pups in an enriched environment where no adult females other than the mother were present. Thus, different levels of maternal care in different environmental conditions could act as indirect mediator for the earliest effects of enrichment on visual system development. Some of the effects of different levels of maternal care on the offspring behavior are long lasting. We measured the visual acuity of differentially reared mice at the end of the period of visual acuity development (postnatal day 45) and at 12 months of age, using a behavioral discrimination task. We found better learning abilities and higher visual acuity in enriched compared to standard reared mice at both ages.  相似文献   
996.
To reduce the number of injections needed to comply with paediatric vaccination requirements, a liquid, hexavalent vaccine (DTaP-IPV-PRP-T-HBs; Hexavac; Aventis Pasteur MSD) has been developed for primary and booster vaccination of infants and toddlers. In extensive clinical studies, Hexavac has been shown to be highly immunogenic. Seroconversion or seroprotective titres of antibodies against all antigens were achieved in the majority of infants following a primary series of three doses administered at 1-2-month intervals from 2 months of age. Hexavac also induced immunologic memory, as evidenced by the anamnestic response to booster vaccination at 12-18 months of age. These responses were comparable with those seen following concomitant administration of Pentavac (DTaP-IPV//PRP-T) and monovalent hepatitis B vaccine (H-B-Vax II), and were also within the ranges observed for other relevant licensed vaccines. Clinical studies comparing the immunogenicity of Hexavac administered at either 2, 3 and 4 months or 2, 4 and 6 months demonstrated that it can be used by either vaccination schedule. A further study also supported the use of primary doses of Hexavac at 3 and 5 months with a booster at 12 months of age. Hexavac demonstrated a good reactogenicity and tolerability profile. The most frequently reported adverse events after both primary and booster doses were local reactions of redness and swelling/induration and a systemic response of mild fever, irrespective of the vaccine used for priming. Hexavac provided immunity against six important childhood diseases with a single injection at each visit.  相似文献   
997.
998.
Data from Berlin (Germany) show a significant correlation between the increase in the stork population around the city and the increase in deliveries outside city hospitals (out-of-hospital deliveries). However, there is no correlation between deliveries in hospital buildings (clinical deliveries) and the stork population. The decline in the number of pairs of storks in the German state of Lower Saxony between 1970 and 1985 correlated with the decrease of deliveries in that area. The nearly constant number of deliveries from 1985 to 1995 was associated with an unchanged stork population (no statistical significance). However, the relevance of the stork for the birth rate in that part of Germany remains unclear, because the number of out-of-hospital deliveries in this area is not well documented. A lack of statistical information on out-of-hospital deliveries in general is a severe handicap for further proof for the Theory of the Stork.  相似文献   
999.
To evaluate the normalization of lymphocyte subsets several years after autologous peripheral blood stem cell transplantation (aPBSCT) and to detect any differences based on the underlying lymphoproliferative diseases, we analyzed the immunological recovery of 149 patients with Non Hodgkin's Lymphoma (NHL), Hodgkin's Disease (HD), Multiple Myeloma (MM). Lymphocyte recovery was assessed before the transplant, on days 15, 30, 60, 90, 120 and on years 1, 2, 4, 6. Analysis of a total of 709 lymphocytes, including total lymphocyte count, CD3 + , CD4 + , CD8 + , CD4 + /CD8 + ratio, CD19 + , CD3 + HLA-DR + , CD16 + 56 + , was performed. The normalization of total lymphocyte counts was achieved between days 14 to 22 following PBSCT. CD3 + cells count showed a normalization after 2 years in the HD and NHL groups and after 4 years in MM group. CD4 + subset achieved normalization during the sixth year in the 3 groups. The CD8 + and CD19 + lymphocytes subsets achieved normal values in the 3 groups at day 60 and at day 120 respectively. CD16 + 56 + and CD3 + /HLA-DR + lymphocytes showed median values above the normal range starting from day 30. Immunological recovery was similar in all 3 groups. Moreover, the recovery of all subsets evaluated was similarly demonstrated within 6 years after aPBSCT.  相似文献   
1000.
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