No abstract

A preliminary examination of Paleogene dinoflagellate cysts from core holes drilled on DSDP Leg 71, Falkland Plateau, indicates that dinoflagellates may be useful for recognizing the Eocene/Oligocene boundary in the southwestern Atlantic Ocean. In addition, data from Hole 511 provide evidence for establishing tentative limits to the age of type material for several dinoflagellate taxa described by Wilson (1967) from erratics at McMurdo Sound, Antarctica. Illustrations and brief comments about morphology or taxonomic relationships are presented for all taxa discussed in this chapter, including informal and undescribed forms.

No abstract

We have shown previously that a plasma fentanyl concentration of 1.67 ng ml-1 reduced the MAC of isoflurane by 50%. By comparing equal degrees of MAC reduction by sufentanil, we may determine the potency ratio of these opioids. Seventy-six patients were allocated randomly to receive predetermined infusions of sufentanil, and end-tidal concentrations of isoflurane in oxygen. Blood samples were obtained 10 min after the start of the infusion, and just before and after skin incision. Any purposeful movement by the patient was recorded. The MAC reduction of isoflurane produced by sufentanil was obtained using a logistic regression model. A sufentanil plasma concentration of 0.145 ng ml-1 (95% confidence limits 0.04, 0.26 ng ml-1) resulted in a 50% reduction in the MAC of isoflurane. At a plasma concentration greater than 0.5 ng ml-1, sufentanil exhibited a ceiling effect.