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H Gomes

Publications and source records attributed to H Gomes.

At least 37 records · Page 2Linked to original sources
PubMed1997

Lexical processing of visually and auditorily presented nouns and verbs: evidence from reaction time and N400 priming data.

We investigated two aspects of lexical organization in normal adults employing behavioral and electrophysiological indices of semantic priming, namely: (1) Is there evidence for differential processing of nouns and verbs? (2) Is there evidence for separate systems for processing of orthographic and phonologic representations of words? Reaction time (RT), N400 amplitude and latency were used to examine the effect of semantic priming on lexical access of auditorily and visually presented nouns and verbs. We found that the temporal patterns of primed RTs and N400 latencies differed for nouns and verbs, indicating a functional difference in processing. However, the absence of topographic differences in N400 between nouns and verbs did not support anatomically distinct representations of these word classes. By contrast, a modality-specific topography at N400, in addition to RT and N400 amplitude differences between auditory and visual conditions, supported the proposed separation of the orthographic and phonologic representations of words. The implications of the findings for general theories of lexical organization are discussed.

Acoustic Stimulation↗
PubMed1997

Storage of feature conjunctions in transient auditory memory.

The purpose of this study was to determine whether feature conjunctions are stored in transient auditory memory. The mismatch negativity (MMN), an event-related potential that is elicited by stimuli that differ from a series of preceding stimuli, was used in this endeavour. A tone that differed from the preceding series of stimuli in the conjunction of two of its features, both present in preceding stimuli but in different combinations, was found to elicit the MMN. The data are interpreted to indicate that information about the conjunction of features is stored in the memory.

Acoustic Stimulation↗
PubMed1997

[Adenocarcinoma of the Vater's ampulla associated with Von Recklinghausen's neurofibromatosis].

Von Recklinghausen's Neurofibromatosis is an autosomal dominant disease of variable manifestations. Association with gastrointestinal and hepatobiliary tumours is well documented, most of them being benign neurofibromas. Other tumours, such as leiomyomas, sarcomas, ganglioneuromas and carcinoids are less frequent. Much rarer is the development of epithelial malignancies and an ontogenic relation is not clear. The authors reports a case of adenocarcinoma of Vater's Ampulla and duodenal neurofibromas, in a patient with Von Recklinghausen's disease, presenting obstructive jaundice.

Adenocarcinoma↗
PubMed1995

HIV-2 infection with a long asymptomatic period.

We give details of a patient infected with HIV-2 which had what we believe to be the longest asymptomatic period so far reported. The infection was probably acquired though a blood transfusion in Africa 27 years ago. At present the patient remains asymptomatic and her cellular defence mechanisms, evaluated by CD+4 lymphocyte counts and hypersensitivity skin tests, are not severely compromised. HIV-2 has come distinct epidemiological, clinical and biological features which are different from the related HIV-1 and deserve investigation in order for its natural history to be better understood.

Female↗
PubMed1995

The mismatch negativity of event-related potentials as a probe of transient auditory memory: a review.

The use of the mismatch negativity as a probe to study the memory upon which it depends is reviewed. Topics about the memory include its duration, its capacity, the kind of information that can be stored in the memory, how the information is stored, whether the memory is accessed in parallel or in series, whether it is hard-wired or can be modified by experience, and its relationship to sensory memory.

Evoked Potentials, Auditory↗
PubMed1994

[Gastroesophageal reflux in infants: ultrasonographic reading of pHmetry].

BACKGROUND: pH monitoring of the distal esophagus has proved both sensitive and specific in the detection of reflux but has several limitations due to changes over time in esophageal pH and possibility of alkaline reflux. Simultaneous ultrasonographic monitoring can be helpful when interpreting the results. POPULATION AND METHODS: One thousand infants (80% under 1 year of age) were examined: 500 suffered from vomiting (310 patients), life-threatening events (65 patients) or repeated respiratory diseases (125 patients). Five hundred infants were controls (320 asymptomatic and 180 sibs of patients with SIDS). pHmonitoring and ultrasonography were performed before and after ingestion of milk by vomiting patients and after administration of orange juice in the other symptomatic patients. Control patients were given milk when asymptomatic or orange juice when they belonged to a SIDS sibship. RESULTS: Ultrasonography permitted to interpret the different phases of the pH curves according to the age of patients, the meals and their nature, the events associated with temporary increase in abdominal pressure, the gravity. pH monitoring was able to recognize 1589 acid reflux but failed to recognize 2091 reflux episodes. CONCLUSIONS: While pHmonitoring is helpful to demonstrate a relationship between the reflux and such events as apnea, bradycardia, cough, ultrasonography defines a risk based on specificity of reflux and laryngeal or esophageal dysfunction.

Esophagitis, Peptic↗
PubMed1993

Ultrasound of the gastroesophageal junction.

In 560 endoscopy examinations performed on infants with severe vomiting, no esophagitis was found without endoscopic herniation of the gastroesophageal junction. The length of the abdominal esophagus therefore appears fundamental in reflux studies. Sonography is one of few techniques able to define the abdominal esophagus in vivo, both in terms of its anatomy and as a functional structure. Accurate assessment of the sonographic canal requires careful measurement under strictly defined clinical conditions. Using such criteria, ultrasound has a better sensitivity than barium studies in detecting small herniations. In addition to the important length measurements of the abdominal esophagus, other morphological and functional data can also be acquired by ultrasound.

Child↗
PubMed1992

Infant apnea and gastroesophageal reflux.

The value of a combination of ultrasound studies and barium swallow examination in the analysis of temporal relationships between apnea and reflux is demonstrated. The two techniques allow acute apneic spells induced by gastroesophageal reflux to be documented and underlying specific digestive tract disorders demonstrated. The high incidence of digestive tract disorders in this area has been identified.

Apnea↗
PubMed1991

Gastro-esophageal reflux: comparative study between sonography and pH monitoring.

Sonography appears highly sensitive in characterizing the severity of gastroesophageal reflux, screening the infants at risk of esophagitis. Sonography is also useful in evaluating efficacy of treatment. In our experience reflux is only damaging if constantly repeated and related to severe hiatal dysfunction. Ultrasound (US) is a good alternative for the assessment of hiatal function and gives furthermore indispensable morphological data.

Child↗
PubMed1987

Sonographic diagnosis of lissencephaly.

Lissencephaly, a developmental malformation characterized by absence of sulci, may be suggested in dysmorphic or epileptic infants. Real time ultrasonographic findings correlated with typical electroencephalographic abnormalities establish the diagnosis.

Brain↗
PubMed1986

Telangiectatic osteosarcoma.

Two cases of telangiectatic osteosarcoma are described. The difficulty in differentiating this tumour from aneurysmal bone cyst is emphasized both from the pathological and radiological aspects.

Adolescent↗
PubMed1983

Abnormal 24-hydroxylation of 25-hydroxyvitamin D in the X-linked hypophosphatemic mouse.

The effect of extracellular phosphate on the control of 25-hydroxyvitamin D3 24-hydroxylase was studied in normal mice and littermates with X-linked hypophosphatemic rickets (Hyp). 24-Hydroxylase activity and plasma concentrations of 24,25-dihydroxyvitamin D3 were significantly higher in Hyp mice than in normal mice when both groups were fed a normal diet containing 1.22% calcium (Ca) and 0.8% phosphorus (Pi). The differential in 24-hydroxylase activity was exaggerated when serum phosphate was reduced in normal mice by means of a low Pi diet or increased in Hyp mice by means of a high Pi diet. Differences in 24-hydroxylase activity between the two groups of mice were also demonstrated in the presence of varying Pi concentrations in vitro. Thus, in both Hyp and normal mice, 24-hydroxylase activity is influenced in a qualitatively similar manner by serum Pi. Plasma concentrations of 1,25-dihydroxyvitamin D3 were the same in normal and Hyp mice. The data are consistent with the hypothesis that control the renal metabolism of 25-hydroxyvitamin D3 in Hyp mice is reset such tht 24-hydroxylase activity is inappropriate high for the prevailing serum phosphate over a wide range of concentrations.

24,25-Dihydroxyvitamin D 3↗