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31.
George O. Poinar Jr. 《Systematic parasitology》1981,2(4):261-266
Summary A new mermithid nematode, Thaumamermis cosgrovei n. gen., n. sp. (Mermithidae: Nematoda) was found parasitizing two terrestrial isopods (Isopoda: Oniscoidea) in California. The hosts, Armadillidium vulgare (Latr.) (a pillbug) and Porcellio scaber (Latr.) (a sowbug) represent the first cases of isopods attacked by mermithid nematodes. The genus Thaumamermis can be distinguished from all previously described mermithids by the extremely dimorphic spicules, one being short and broad and the other long and filiform. It has been discovered that the nematodes are infected with an iridiovirus which commonly destroys the isopod hosts. ac]19800917 相似文献
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Activation of the sympathetic system by phencyclidine (PCP) should result in catecholamine release from the adrenals. However, adrenalectomy does not reduce PCP-induced hypertension. In an attempt to rectify this inconsistency, the direct effects of PCP on the bovine adrenal medulla were examined. At (3×10?6M), PCP reduced the acetylcholine-(ACh)-induced catecholamine release by 50%. Surprisingly, barium-induced secretion of catecholamines was also reduced by PCP. ACh-induced catecholamine release was not altered by 10?3M 4-aminopyridine (4 AP), the potassium channel blocker. Thus, calcium antagonist actions of PCP and consequent block of catecholamine secretion from adrenal medulla may explain the lack of effect of adrenalectomy on PCP-induced hypertension. Possible contributions of calcium and/or potassium channel blockade to other manifestations of PCP overdosage are discussed. 相似文献
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Kathryn M. Denkowski George C. Denkowski 《Applied psychophysiology and biofeedback》1984,9(3):353-364
This study examined whether group progressive relaxation training was as effective as individual EMG biofeedback training in facilitating the academic achievement and self-control of 45 hyperactive elementary school children. Academic achievement was assessed with the Gates-MacGinities Reading Tests, and self-control was measured with the Nowicki-Strickland and the Teacher Rating scales. Eight sessions were scheduled at weekly intervals. Progressive relaxation was conducted in groups of seven or eight and was induced with a commercial audiocassette program. EMG training augmented frontalis biofeedback with those taped exercises. A placebo group listened to taped children's stories. Multivariate analysis of variance indicated no significant differences among the three contrast groups when all dependent variables were considered together. However, univariate F values and discriminant analysis disclosed locus of control to be significantly more internal for the progressive relaxation condition. Also, differences between the two relaxation and the placebo groups, though not statistically significant, were all in the expected direction. While the relative efficacy of group progressive relaxation could not be established conclusively, the data appeared sufficiently positive to warrant further investigation of this cost-effective prospective intervention.The opinions expressed by the authors are not necessarily those of their respective institutions. 相似文献