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41.
Parle-McDermott A Mills JL Kirke PN O'Leary VB Swanson DA Pangilinan F Conley M Molloy AM Cox C Scott JM Brody LC 《Journal of human genetics》2003,48(4):190-193
The thermolabile variant (677TT) of methylenetetrahydrofolate reductase (MTHFR) is a known risk factor for neural tube defects
(NTDs). The relationship between a second MTHFR polymorphism (1298A→C) and NTD risk has been inconsistent between studies.
We genotyped 276 complete NTD triads (mother, father and child affected with an NTD) and 256 controls for MTHFR 1298A→C. Our
findings do not support a role for the 1298A→C polymorphism in NTDs (OR 0.85 (95% CI 0.49–1.47), p= 0.55), nor do we observe a combined effect with the 677C→T polymorphism.
Electronic Publication 相似文献
42.
Coincident pre- and postsynaptic activity induces synaptic plasticity at the Schaffer collateral synapse onto CA1 pyramidal neurones. The precise timing, frequency and number of coincident action potentials required to induce synaptic plasticity is currently unknown. In this study we show that the postsynaptic activity required for the induction of long-term potentiation (LTP) changes with development. In acute slices from adult rats, coincident pre- and postsynaptic theta burst stimulation (TBS) induced LTP and we show that multiple high-frequency postsynaptic spikes are required. In contrast, in acute slices from juvenile (P14) rats, TBS failed to induce LTP unless the excitatory postsynaptic potentials (EPSPs) were of sufficient magnitude to initiate action potentials. We also show that coincident individual pre- and postsynaptic action potentials are only capable of inducing LTP in the juvenile when given at a frequency greater than 5 Hz and that the timing of individual pre- and postsynaptic action potentials relative to one another is not important. Finally, we show that local tetrodotoxin (TTX) application to the soma blocked LTP in adults, but not juveniles. These data demonstrate that somatic spiking is more important for LTP induction in the adult as opposed to juvenile rats and we hypothesize that the basis for this is the ability of action potentials in the postsynaptic CA1 pyramidal neurone to back-propagate into the dendrites. Therefore, the pre- and postsynaptic activity patterns required to induce LTP mature as the hippocampus develops. 相似文献
43.
Matz PE Foster GD Faith MS Wadden TA 《Journal of consulting and clinical psychology》2002,70(4):1040-1044
Predictors of body image dissatisfaction (BID) among obese people are poorly understood. In 79 obese women seeking weight reduction, associations with BID of self-esteem, youth teasing, adult teasing, and internalization of sociocultural appearance standards (ISAS) were studied. Analyses revealed that only self-esteem, adult teasing, and ISAS predicted BID. Results highlight the importance of adulthood self-esteem and interpersonal-cultural context--rather than childhood experiences--in predicting adulthood BID. 相似文献
44.
R G Robinson M Tortosa J Sullivan E Buchanan A E Andersen M F Folstein 《Psychosomatic medicine》1983,45(4):283-292
Hospitalized patients with anorexia nervosa (N = 17) or bulimia (N = 11) were given a standard liquid meal containing 400 calories. Using analogue scales, bulimic patients were found to have greater anxiety, lower mood, lower sexual arousal, and more fear of fatness than either control or anorectic patients. This finding of increased general "dysphoria" in bulimic patients persisted after the meal without any significant premeal to postmeal changes. Anorectic patients also differed from controls, but less than the bulimic patients. Some measures of anxiety correlated significantly with body mass index before the meal in bulimic patients, whereas in anorectic patients the correlation was significant only after the meal. 相似文献
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49.
Neuroimmunomodulation with enkephalins: enhancement of human natural killer (NK) cell activity in vitro 总被引:4,自引:0,他引:4
R E Faith H J Liang A J Murgo N P Plotnikoff 《Clinical immunology and immunopathology》1984,31(3):412-418
To further define the effects of enkephalins on immune function, the effect of methionine-enkephalin and leucine-enkephalin on natural killer cell (NK) activity in isolated human peripheral blood lymphocytes was investigated. Incubation of lymphocytes with either enkephalin resulted in significant increases in natural killer cell activity. At effector:target cell ratios of 11:1 methionine-enkephalin significantly (P less than 0.05) enhanced NK activity at dilutions of 10(-6), 10(-8), 10(-10), and 10(-14) mg/ml, while leucine-enkephalin significantly (P less than 0.05) enhanced NK activity at dilutions of 10(-4), 10(-6), 10(-8), 10(-10), and 10(-14) mg/ml. Cells from individuals with low NK activity showed greater percentage increases in NK activity following enkephalin than did cells from individuals with high NK activity. 相似文献
50.
Rabbits with either sham or septal lesions recieved differential classical conditioning training in which tones of different frequencies served as CSs and paraorbital shock served as the UCS. Eyeblink (EB), EMG, and heart rate (HR) CRs were concommitantly assessed. Free field activity was also studied in selected animals. Animals with septal lesions revealed an impaired EB discrimination which resulted from increased responding to the CS-. These animals showed HR CRs of greater magnitude than sham animals. The HR discrimination was, however, unimpaired by septal lesions. Differential EMG activity also occurred, but was unaffected by septal destruction. Septal lesions resulted in greater free-field activity associated with visual stimulation, but no differences were obtained between septal and sham animals in the dark. It is suggested that these results were due to an enhanced reactivity to environmental stimulation, possibly related to dysfunctions of the orienting reflex. 相似文献