Evaluation of reliability of pooling stool specimens from different patients and detection of Giardia lamblia antigen by microtiter enzyme-linked immunosorbent assay.

We have shown that stool samples from different patients can be pooled at a 1:2 dilution and reliably assayed for Giardia lamblia antigen by a commercial microtiter enzyme-linked immunosorbent assay (ELISA) system (LMD Laboratories, Inc., Carlsbad, Calif.). Laboratories can reduce reagent costs by pooling specimens submitted for the detection of Giardia antigen by ELISA.

Language laterality in Navajo reservation children: dichotic test results depend on the language context of the testing.

Language lateralization in 40 Navajo and 20 Anglo fifth graders was assessed via the Dichotic Consonant-Vowel Task (DCVT). One group of Navajo children was tested by an experimenter who spoke only Navajo with them. The other Navajo group and the Anglo group were tested by an experimenter who spoke only English to them. Strong right ear advantages (REAs) were obtained for the Anglo group and for the Navajo group tested by the Navajo-speaking experimenter. The Navajo group tested by the English-speaking experimenter showed minimal, nonsignificant REAs. Previous findings of an absence of REAs in Native American children failed to consider the possibility that this might occur only when the experimenter does not speak the dominant language of the children. Our results are not consistent with the view that Native Americans are more right hemisphere dominant as a function of an "appositional" mode of language and thought.