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991.
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These experiments examined the effects, on retention, of posttraining intra-amygdala administration of norepinephrine (NE), and propranolol. Rats were trained on a one-trial step-through inhibitory avoidance task and tested for retention 24 h later. Injections were administered bilaterally (1.0 microliter/injection) through chronically-implanted cannulae. Low doses of NE (0.1 or 0.3 microgram) administered shortly after training enhanced retention while higher doses (1.0 or 5.0 micrograms) were ineffective. Retention was not affected by NE administered 3 h after training. The effect of intra-amygdala NE on retention is blocked by simultaneous administration of propranolol (0.2 microgram). This finding suggests that the memory-enhancing effect of NE may be mediated by beta-receptors. Posttraining intra-amygdala NE also attenuated the retention deficit produced by adrenal demedullation. Further, intra-amygdala injections of propranolol (0.2 microgram) blocked the enhancing effect, on retention, of posttraining s.c. injections of epinephrine. These findings suggest that activation of noradrenergic receptors in the amygdala may be involved in memory processing and may play a role in the memory-modulating effect of peripheral epinephrine.  相似文献   
994.
Summary Maximal oxygen uptake was assessed in 101 randomly selected 8 and 13 year old children. In both age groups a significantly higher aerobic capacity was found in boys than in girls, both in absolute terms and when maximal oxygen uptake was related to body weight, lean body mass and lean leg volume. Among girls, maximal oxygen uptake per kg body weight was lower in the older than in the younger (p<0.05). Estimation of spontaneous physical activity, by means of a questionnaire and the actometry method, indicated that physical activity was greater in children with a high than in those with a low aerobic capacity.  相似文献   
995.
Stomatococcus mucilaginosus was isolated from the blood of a patient with endocarditis and a past history of drug abuse and aortic valve replacement. At autopsy, Gram stain of the aortic valve revealed gram-positive cocci. Our isolate was atypical for S. mucilaginosus in that colonies were nonmucoid and nonadherent to agar surfaces. Cellular capsules were demonstrated by light and electron microscopy. Phenotypic characteristics identified by conventional methods as well as profile numbers obtained by using two commercial identification systems for staphylococci, the API Staph-Ident and the dms Staph Trac, are presented. Practical tests that differentiate S. mucilaginosus from the genera Micrococcus and Staphylococcus include growth on nutrient agar containing salt and lysostaphin susceptibility. Additional tests that helped differentiate our isolate from group D streptococci included hydrolysis of L-pyrrolidonyl-beta-naphthylamide and streptococcal serogrouping.  相似文献   
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Hallux rigidus (osteoarthritis leading to reduced motion) is one of the most common afflictions of the first metatarsophalangeal joint. The diagnosis is based on the presence of pain, specific physical findings, and certain radiologic features. In this essay, we illustrate the grades of radiologic changes, which are an integral part of the surgeon's preoperative evaluation, and show examples of the postoperative radiologic appearance.  相似文献   
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Vitamin K1 functions in the conversion of glutamate residues, present in certain bone peptides, into the putatively active γ-carboxyglutamate form. We have shown previously that the circulating levels of vitamin K1 are depressed in osteoporotic patients. However, it is known that menaquinones (vitamin K2:MK) may be more effective than vitamin K1 in this conversion of the inactive to active form of glutamate residues. A procedure for measuring such menaquinones has now demonstrated a marked deficiency of MK-7 and MK-8 in patients with osteoporotic fractures. It is suggested that estimates of circulating levels of K1, MK-7, and MK-8 might provide a biochemical risk marker of osteoporotic fractures.  相似文献   
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