Induction of disseminated virulent cytomegalovirus infection by immunosuppression of naturally chronically infected wild mice.

Wild mice immunosuppressed with antithymocytic sera show a high incidence of disseminated virulent cytomegalovirus infection.

Sea otters: their role in structuring nearshore communities.

A comparison of western Aleutian Islands with and without sea otter populations shows that this species is important in determining littoral and sublittoral community structure. Sea otters control herbivorous invertebrate populations. Removal of sea otters causes increased herbivory and ultimately results in the destruction of macrophyte associations.

A spontaneous lower motor neuron disease apparently caused by indigenous type-C RNA virus in wild mice.

A high incidence of spontaneous lower-limb paralysis occurred in a population of wild mice () which had a high incidence of naturally occurring lymphoma and elevated indigenous type-C virus activity. Experimental transmission evidence indicated that both the neurologic and lymphomatous disorders almost certainly were caused by the indigenous type-C virus. The virus appeared to have a direct neurotropic effect on anterior horn neurons in the lower spinal cord.

Isolation of a neurotropic type C virus.

A neurogenic paralysis of the lower limb can be induced and serially transmitted in mice by a nontransforming type C virus strain that originated in an embryo of a wild mouse. The virus exerted a neurotropic effect on the anterior horn neurons.

The heterogeneity of the anticoagulant response to heparin.

Difficulties in evaluating the anticoagulant effect of heparin led to studies of the rate of disappearance of its effect on the whole body partial thromboplastin time, and of its simultaneously bioassayed plasma concentration. The slope of the anticoagulant's dose-effect curve varied with each subject's baseline coagulation status, which probably accounts for the wide range of clinically observed responses to the drug. The mean rate of disappearance of bioassayed heparin was less than the mean rate of disappearance of the drug's effect on the clotting time, probably because of heparin's extensive binding to the plasma proteins which comprise its site of action.

Oil spills: method for measuring their extent on the sea surface.

It is difficult to estimate the area affected by an oil spill at sea, the degree of coverage by oil pollutants within the affected area, and the quantity of pollutants involved. Estimates of volumes and flow rates are based on estimated changes in areal extent of the spill. Uncertainties in measurement of area degrade the accuracy of estimating other parameters.