Differences in preschool children's conceptual strategies when thinking about animate entities and artifacts.

Two-, 3-, and 4-year-old children viewed 10 stimulus sets. Each set contained a sample picture (e.g., a dog), a basic-level taxonomic match (e.g., another dog), a thematic match (e.g., a bone), and an irrelevant match (e.g., a pen). The children were asked to choose a match that "goes with" each sample. Sample pictures were either animate entities or artifacts. The children's choice behavior indicated that a shift occurs between 3 and 4 years of age from a taxonomic bias to a thematic bias and that, at both ages, animate sample stimuli enhance the children's tendency to adopt thematic conceptual strategies. These data are consistent with recent suggestions that thematic thinking presupposes basic-level taxonomic thinking during early conceptual development and that this developmental progression occurs more rapidly in some domains of knowledge than in others.

The nonreciprocating robot: effects on verbal discourse, social play, and social referencing at two years of age.

2-year-old children interacted with a robot in a large playroom while their mother sat quietly in the corner. Identical vocalizations from the robot had very different effects on 3 dimensions of the children's behavior when the vocalizations were embedded in reciprocating and nonreciprocating social structures. The reciprocating robot produced (1) more topic-maintaining verbal dialogue, (2) less physical and more linguistically mediated social play, and (3) gender-specific effects on the children's tendency to visually reference their mother during the play session. The data are discussed with reference to the frequently encountered assumption that reciprocal social structures have an impact on children's behavior when the quantity and other qualitative dimensions of social stimulation are held constant, and with reference to the children's attributions about the robot as a social partner.

Directive interactions and early vocabulary development: the role of joint attentional focus.

Maternal directiveness, assessed by the mother's use of prescriptives, is correlated with slow vocabulary development. As prescriptives are most often used to redirect a child's attention to a different object or activity, it is hypothesized that attentional regulation underlies this negative relationship. In the present study, twelve mothers were videotaped interacting with their children aged 1;1, and 100 maternal utterances were coded for pragmatic intent. Prescriptives were coded as either changing (leading) or following the child's focus of attention. Only the frequency of mothers' follow-prescriptives correlated significantly with a productive vocabulary measure taken at 1;10. This correlation was high and positive, indicating that, given joint focus, directing a 13-month-old's behaviour can have beneficial effects on subsequent vocabulary development.

Effects of mother-infant social interactions on infants' subsequent contingency task performance.

20 3-month-old infants participated in a nonsocial contingency task immediately following a social interaction with their mothers. A measure of the time the dyads spent in a state of vocal turn-taking predicted individual differences in the infants' subsequent performance on the contingency task. These results parallel the social transfer effects we reported earlier in which the turn-taking dimension of social structure was experimentally manipulated to assess its effect on a subsequent nonsocial contingency task.

Social contingency effects on subsequent perceptual-cognitive tasks in young infants.

3 experiments with 3-month-old infants compared the effects of contingent and noncontingent adult-infant social interactions on subsequent infant-controlled habituation and choice tasks. Infants who experienced a prior noncontingent social interaction tended to adopt response strategies that reduced the density of stimulation during these subsequent nonsocial tasks. The results are discussed in terms of their generality and the types of mechanisms that might mediate these transfer effects from social to nonsocial procedures.

Endoscopic ultrasonography in achalasia.

Six patients with known achalasia were examined by endoscopic ultrasonography before dilatation therapy. At the level of the lower esophageal sphincter, a typical enlargement of the echolayer corresponding to the muscularis propria was observed in 5 cases. Endoscopic ultrasonography is a complementary procedure to manometry and x-ray for diagnosing achalasia. It helps differentiate achalasia from pseudoachalasia. In pseudoachalasia there is tumor infiltration.

Ultrasound-guided percutaneous and transhepatic cholecystostomy: a complementary procedure to therapeutic endoscopy.

Percutaneous cholecystostomy is an expanding technique since the use of ultrasonography permits a precise puncture of the gall bladder. Cholecystitis is a classical complication of endoscopic maneuvers in the biliary tract or can be associated with obstructive jaundice. Following their results the authors conclude on the usefulness of percutaneous cholecystostomy as a complementary procedure to non-operative management of biliary diseases.

[Treatment of adenocarcinoma of Vater's ampulla]. / Traitement de l'adénocarcinome de l'ampoule de Vater.

We reviewed the records of 51 patients. In two-thirds of the cases the main symptom was icterus; one third presented with pain. The whole group underwent a retrograde choledocho-pancreatography. An abnormal papilla was found in 80% of the cases. This finding proved to be of sufficient diagnostic importance without the necessity of an associated choledocho-pancreatography for diagnostic confirmation. Although in the majority of the cases the choledochus proved to be dilated, pancreatic duct enlargment was only noted in 50%. The only treatment in the very elderly patient was endoscopic sphincterotomy. Younger patients underwent a duodeno-pancreatectomy preceded by an endoscopic sphincterotomy. The morbidity and mortality associated with endoscopic opacification of the biliary and pancreatic ducts and sphincterotomy in this setting is much higher than for all other indications in general. For this reason we propose to perform a choledocho-pancreatography only when indispensable for diagnostic purposes (nl. papilla) or when endoscopic sphincterotomy is the chosen treatment modality.

Endoscopic biopsies of the papilla of Vater at the time of endoscopic sphincterotomy: difficulties in interpretation.

The hypertrophic aspect of tissue after endoscopic papillotomy may suggest the diagnosis of a small periampullary tumor. In our experience of 55 periampullary carcinomas, the diagnosis was confirmed histologically in 50% of the cases before endoscopic papillotomy and in 100% of the cases when the biopsies were performed immediately after papillotomy. With this in mind, biopsies were performed in 22 cases of benign biliary tract disease after endoscopic papillotomy. Biopsies within the first 48 hours after endoscopic papillotomy showed cellular atypism.

Nd-YAG laser, a new palliative alternative in the management of esophageal cancer.

Ten patients with unresectable esophageal malignant tumor have been managed by Nd-YAG laser palliative therapy. Esophageal obstruction, and dysphagia, the most frequent symptoms, were relieved in all cases after periods ranging from 5 to 14 days. The mean total energy required was 26.121 watts sec-1. No serious immediate or late complication was encountered, except for one small transient bleeding without clinical repercussion. Two relapses of dysphagia were successfully managed by the same procedure. This new palliative approach has to be compared with the other available methods, surgical resection and bypass procedures, radiotherapy or endoscopic prosthetic intubation. Its high degree of effectiveness in providing rapid relief of dysphagia, and its low morbidity rate will give to laser therapy an important place in the future palliative management of esophageal cancer, either alone or in combination with other treatments.

[Complementarity and limits of the different technics of pancreatic morphologic investigation for the diagnosis of acute pancreatitis and complications (author's transl)]. / Complémentarité et limites des différentes méthodes d'investigation morphologique dans le diagnostic des pancréatites aiguës et de leurs complications.

The authors have previously proposed the endoscopic retrograde cholangio-pancreatography as a technic to be used systematically in acute pancreatitis; it offers a precise diagnosis of microlithiasis and a possibility of an immediate endoscopic treatment. They have studied the pancreatographic patterns in 355 cases of clinical acute pancreatitis; the pancreatogramm allows the diagnosis of chronic pancreatitis in acute phase in 1/3 of the patients; necrosis is present in 12% of the 240 patients without any radiological signs of chronic pancreatic disease. The computerized axial tomography gives a precise definition of the extra-pancreatic extension of the necrosis; the ultra-sound technic is better for the late complications of acute pancreatitis. The authors consider that these 3 examination technics must be performed at the admission or/and be part of the workup before surgery.

[Interest of bilio-pancreatic morphologic study in management of acute pancreatitis (author's transl)]. / Traitement de 30 cas de pancréatite aiguë nécrotico-hémorragique par une dialyse péritonéale médicale.

The interest of morphologic investigations in the diagnosis, the prognosis and the treatment of acute pancreatitis was analyzed in a series of 120 patients. The systematic endoscopy of the biliary tract yields a distinction between the biliary and the non-biliary sources of pancreatitis and can be followed immediately by an endoscopic sphincterotomy. Th morphological study of the bilio-pancreatic area can complete the prognostic indexes defined by the clinical and biological data, document the extension of the intra- and extrapancreatic necrosis and precise the indication and the choice of a surgical treatment.