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We present our comments on the above article.  相似文献   
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Anti-S-100 Serum blocks long-term potentiation in the hippocampal slice   总被引:2,自引:0,他引:2  
S-100 is a calcium-binding, glial protein which has been shown to be involved in behavioral learning and memory tasks. Long-term potentiation (LTP) in the hippocampus is a long-lasting enhancement of synaptic efficacy evoked by repetitive afferent stimulation. When anti-S-100 serum is applied by pressure ejection onto the stratum radiatum of area CA1 of the hippocampal slice, the amplitude of the extracellularly recorded population spike is not affected. However, repetitive stimulation of the afferents during S-100 application failed to produce LTP. At a distant site in the same slice, LTP occurs normally. Preimmune normal rabbit serum had no effect on the development of LTP. It appears that S-100 protein is involved in the establishment of LTP.  相似文献   
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There is evidence that long-term maintenance of a low-fat diet reduces preference for high-fat foods. Sensory evaluation of the taste of fat, and preference for high and low-fat foods were studied in a group of former participants in a randomized dietary intervention trial aimed at lowering fat consumption. Intervention subjects consuming less than 25% of daily calories as fat and control subjects consuming more than 35% of daily calories as fat agreed to be in a "taste perception" study. In Study 1, subjects tasted 20 dairy solutions containing different levels of fat and sugar. Subjects rated the perceived intensity of fat taste, and of liking, for each of the solutions. In Study 2, subjects were asked to taste and rate 4 high-fat and 4 low-fat snack foods, and were then allowed to freely consume these foods in a preference test. Intervention and control subjects were similar in their sensory evaluation of the taste of fat in Study 1. In Study 2, intervention subjects reported a reduced hedonic rating of the taste of high-fat snack foods compared to control subjects, yet intervention subjects consumed the same amount of high-fat snack foods as control subjects. We conclude that a successful outcome in a dietary intervention may be due to social and cognitive factors, in addition to potential changes in hedonic response to fat.  相似文献   
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A model for training the trainers of child care providers that employs Vygotsky's framework of the Zone of Proximal Development is described. This efficient training mechanism proposes mentoring relationships as a means to meet the developmental needs of experienced child care professionals and improve the quality of existing child care programs.The authors would like to thank Dr. Bille Thomas and the satellite resource center directors and staff members for their work on the project.  相似文献   
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This double-blind study compared ampicillin-sulbactam 3 g versus cefoxitin 2 g in 136 adult patients at risk for developing an infection after abdominal surgery. Separate randomization schedules were used for colorectal, upper gastrointestinal/biliary, and other abdominal procedures. Study antibiotics were administered within 30 minutes before incision and repeated 6 hours later. Patients having colorectal surgery received a third dose of antibiotic 6 hours after the second. Efficacy evaluations were made on 123 patients, 62 in the ampicillin-sulbactam group and 61 in the cefoxitin group. The overall postoperative infection rates were 12.9% for ampicillin-sulbactam and 9.8% for cefoxitin (p>0.05); one wound infection occurred in each group. Adverse events were experienced by 13.2% of the ampicillin-sulbactam and 19.1% of the cefoxitin recipients (p>0.05). Cost-minimization analysis revealed that ampicillin-sulbactam was a cost-effective alternative to cefoxitin for the prevention of infection after abdominal surgery.  相似文献   
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