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Abstract  Sisyra pedderensis sp.n. is described from Lake Pedder, Tasmania, bringing to seven the number of described species of Sisyridae (Spongillaflies) known from Australia.  相似文献   
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In this study we have examined the effect of agents known to perturb certain signal transduction pathways on the biological responses of target cells to stimulation with interleukin-1 (IL-1). In the murine thymoma cell line EL4, IL-1 stimulation results in the secretion of interleukin-2 (IL-2), which was subsequently measured by proliferation of an IL-2-dependent cell line. Agents that elevated intracellular cAMP blocked or partially blocked IL-1 induction of IL-2 secretion, whereas agents that activated protein kinase C (PKC) resulted in a synergistic enhancement. Both pertussis and cholera toxins also inhibited IL-1-induced IL-2 secretion, although probably by acting at different levels. IL-1 simulation of human and murine fibroblasts resulted in release of prostaglandin E2. This response was inhibitable by pertussis toxin but not by cholera toxin, whereas co-stimulation of the fibroblasts with IL-1 and phorbol ester resulted in a synergistic response. Murine fibroblasts could also be stimulated to proliferate by IL-1, and this response was also inhibitable by pertussis toxin. These findings are consistent with coupling of the IL-1 receptor to a signalling pathway via a pertussis toxin substrate.  相似文献   
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There is a widespread perception that coral larvae require stable (lithified) rock substrates to settle during reef initiation, and that these substrates are typically carbonate. However, reef core data show that reef establishment can also occur directly above a wide range of unlithified, non-carbonate sediment substrates, including relict alluvial sands and gravels. The mechanisms by which these lithic substrates are colonised and stabilised are not, however, well documented. Here, we describe such processes from an intertidal setting on the inner-shelf of the Great Barrier Reef, in a setting directly analogous to that which would have existed around many inner-shelf high islands during the post-glacial marine transgression when mid-Holocene reef initiation was taking place. Communicated by Geology Editor Dr. Bernhard Riegl  相似文献   
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The results of treatment for patients with seminoma of the testis by orchidectomy and irradiation are so satisfactory that retroperitoneal lymph node dissection is no longer practised. However, this operation is still used routinely in some centres for patients with testicular teratomas despite the lack of evidence that it gives better results than those obtained with irradiation followed by removal of lymphographically demonstrable residual tumour and in the face of the high incidence of ejaculatory impotence which follows. On grounds of preservation of sexual function and fertility there is a great advantage to be gained from the latter form of treatment. Thirty-four of our patients between the ages of 25 and 45 years treated by irradiation to the para-aortic and iliac nodes for testicular tumours fathered 52 children to term after their treatment.  相似文献   
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