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761.
Abstract Bacterial ribosomes have been shown to induce effective humoral and cellular immunological responses to whole microorganisms. In this study, the numbers of specific antibody producing cells directed towards Klebsiella pneumoniae, Streptococcus pneumoniae, Streptococcus pyogenes and Haemophilus influenzae ribosomes or whole bacteria sonicates were compared in the peripheral blood and tonsils of 7 childrens, and in the tonsils, mesenteric and cervical lymph nodes of 100 sheep. No significant difference was noted between the two types of antigens, confirming that ribosomal preparations are able to mimic the immunogenicity of whole bacteria in the mucosae-associated lymphoid tissue.  相似文献   
762.
Previous research indicates that both the extent and timing of muscular activation at the knee can be influenced by muscle activity state, joint angle, weight-bearing status and trunk position. However, little research to date has evaluated protective neuromuscular response times and activation patterns to an imposed perturbation with the knee joint in a functional, weight-bearing stance. Hence, we designed a lower extremity perturbation device to produce a sudden, forward and either internal or external rotation moment of the trunk and femur relative to the weight-bearing tibia. Surface electromyography (EMG) recorded long latency reflex times of the medial and lateral quadriceps, hamstring and gastrocnemius muscles in 64 intercollegiate lacrosse and soccer players in response to both internal and external rotation perturbation. We found the gastrocnemius fired significantly faster that the hamstring, which in turn fired significantly faster than the quadriceps. There was also a significant difference in activation times of the medial and lateral hamstring not found for the quadriceps or gastrocnemius muscles. Our findings confirmed that reactive neuromuscular responses following this functional perturbation differ markedly from those previously reported using seated, partial weight-bearing and/or uni-planar models under relaxed conditions.  相似文献   
763.
Cats and rats secrete very small quantities of gastric juice ( GJ ). In order to measure the Intrinsic Factor (IF) in GJ of animals certain modifications are necessary. It is very important to select with great care pernicious anemia sera which will be used to cross react with the animals' IF to determine their IF level by radioimmunoassay. The technic described here enables the dosage of low quantities of IF with a 7 per cent coefficient of variation.  相似文献   
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Neurofeedback (NFB) is an emerging treatment for children with autism spectrum disorder (ASD). This pilot study examined the feasibility of NFB for children with ASD. Ten children ages 7–12 with high functioning ASD and attention difficulties received a NFB attention training intervention. A standardized checklist captured feasibility, including focus during exercises and academic tasks, as well as off-task behaviors. Active behaviors and vocalizations were the most frequent off-task behaviors. Positive reinforcement and breaks including calm breathing exercises were the most common supports. Low motivation was associated with higher feasibility challenges, yet parental involvement and accommodations were helpful. This pilot study shows that it is feasible to conduct NFB sessions with children with high functioning autism and attention difficulties.  相似文献   
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Intracarotid infusion of LH-RH to female rabbits stimulated a significant increase in plasma LH concentration in the jugular vein. This response varied with the reproductive state of the animal, with a greater release occurring in oestrous (spontaneous or oestrogen-induced) and non-receptive does than in pseudopregnant or ovariectomized animals. If ovariectomized rabbits were pretreated with oestrogen, the pituitary response to LH-RH was restored. These findings suggest that there is little change in pituitary sensitivity to LH-RH infusion between oestrous and non-receptive rabbits, although pseudopregnancy (high physiological levels of progesterone) or ovariectomy inhibit its ability to respond to a releasing-hormone stimulus.  相似文献   
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