Biomedical subjects

R Pearl

Publications and source records attributed to R Pearl.

At least 37 records · Page 2Linked to original sources

PubMed1984

Conversational interactions between mothers and learning-disabled or nondisabled children during a problem-solving task.

This study focused on mother-child interactions during a problem-solving task to determine whether (a) mothers of learning-disabled children engage in conversational buffering to facilitate their child's participation in the task, and (b) whether learning-disabled children differ from nondisabled children in their use of language with their mothers. The results of this study provide some evidence that mothers of both learning-disabled and nondisabled children engage in conversational buffering, although there were few differences between the mothers of the learning-disabled and nondisabled children. Differences between learning-disabled and nondisabled children showed that the learning-disabled were more likely to agree with and less likely to disagree with their mothers than were the nondisabled children. These findings provide some evidence of maternal conversational buffering and suggest that learning-disabled children's previously reported unassertive conversational style in peer interactions extends to talk with their mothers.

Child↗

PubMed1984

Amino acid clearance and prognosis in surgical patients with cirrhosis.

To measure the effects of cirrhosis on amino acid (AA) flux and to assess the value of the central plasma clearance rate of amino acids (CPCR-AA) as a hepatocyte function test, 35 patients with cirrhosis were studied before and after operation. Fourteen of these patients died after the operation. CPCR-AA measures the number of milliliters of plasma cleared of AA per minute by the liver and other visceral tissues. It is the ratio of AA entry rate into plasma (from peripheral tissues plus infusion) to the arterial AA plasma concentration. Preoperative CPCR-AA measurements in 21 fasted patients with cirrhosis who were not infected revealed a pattern of AA plasma concentration and exchange similar to that previously observed in patients with sepsis with normal liver function. Whereas the concentration of AA in both groups was slightly lower than normal, the CPCR-AA of each was more than four times that of normal postabsorptive people (p less than 0.01). However, preoperative values of CPCR-AA in patients with cirrhosis who survived was 220 +/- 26 ml/M2/min while that in those who died was 97 +/- 16 ml/M2/min (p less than 0.001). Postoperative measurements remained relatively unchanged: survivors 212 +/- 24 ml/M2/min and those who died 89 ml/M2/min (p less than 0.0005). Measurements in vitro of the hepatic protein synthetic rate in liver biopsy specimens taken at operation correlated well with CPCR-AA values obtained immediately before operation in 10 patients (r = 0.73; p less than 0.01). Thus in patients with cirrhosis visceral amino acid uptake and hepatic protein synthesis are maximally stimulated. Nevertheless, if the preoperative CPCR-AA does not approach the value of 284 +/- 76 ml/M2/min previously observed in patients with sepsis who recover, the patient with cirrhosis is prone postoperatively to die of overwhelming infection and multisystem failure.

Amino Acids↗

PubMed1982

Learning disabled children's syntactic proficiency on a communicative task.

Previous studies have generally examined learning disabled children's syntactic ability either on structured tasks or by analyzing oral language samples collected under conditions not typical of natural communicative settings. Thus, these studies are of limited value in exploring the impact of learning disabled children's deficits in linguistic structure on their use of language in social contexts. The purpose of this study was to investigate learning disabled children's syntactic proficiency during a task requiring them to convey information to a listener. Subjects were selected on the bases of teacher ratings, reading achievement scores, and Peabody Picture Vocabulary Test IQ scores within the normal range; those children identified as learning disabled received low ratings and demonstrated underachievement (below 40th percentile for their grade) in reading. Oral language samples were collected by having learning disabled and normally achieving children in grades two, four, six, and eight participate in a referential communication task in which they described abstract shapes to an experimenter. The length and syntactic complexity of the children's descriptions were assessed. Learning disabled children in all grades were found to produce shorter mean t-units and shorter mean main clauses than nondisabled children even on this relatively simple communicative task. Although learning disabled children's linguistic problems have previously been characterized as subtle, these findings suggest that their productive language deficits may be significant enough to interfere with even the informal and elliptical conversations characteristic of communication among peers and family members.

Adolescent↗

PubMed1981

The classification of acute leukaemia in childhood.

In 1976 a French, American and British (FAB) cooperative group proposed a morphological classification of acute leukaemia which they hoped would prove more reproducible than previous classification. We present our preliminary experience with this classification, based on a 2-year study of 39 patients. Cytochemical and cell surface marker characteristics of the leukaemic cells were also studied. We found this classification to be satisfactory but some problems were noted in regard to its reproducibility, especially in acute lymphoblastic leukaemia (ALL). Cell surface markers were absent in the majority of cases of ALL ("null cell" type), while the remainder had T-cell characteristics. No B-cell types were seen. Cytochemical staining patterns clearly distinguished ALL from acute myeloid leukaemia (AML) and also helped to categorize AML into its subtypes. The implications of our finding are discussed.

Acute Disease↗

PubMed1981