Search PubMed⌕ Search

Biomedical subjects

J Ramos

Publications and source records attributed to J Ramos.

At least 199 records · Page 11Linked to original sources
PubMed1968

Effect of altitude on oxygen binding by hemoglobin and on organic phosphate levels.

The relationship between oxygen dissociation and 2,3-diphosphoglycerate (2,3-DPG) in the red cell has been studied in subjects moving from low to high altitude and vice versa. Within 24 hr following the change in altitude there was a change in hemoglobin affinity for oxygen; this modification therefore represents an important rapid adaptive mechanism to anoxia. A parallel change occurred in the organic phosphate content of the red cell. While this study does not provide direct evidence of a cause-effect relationship, the data strongly suggest that with anoxia, the observed rise in organic phosphate content of the red cell is responsible for increased availability of oxygen to tissues.

Adenosine Triphosphate↗
PubMedDate not supplied

Use of confidence intervals and sample size calculations in health economic studies.

OBJECTIVE: To discuss the calculation and application of confidence intervals in pharmacoeconomic studies. DATA SYNTHESIS: The increasing frequency with which pharmacoeconomic evaluations are made within clinical trials makes it possible to obtain information on the outputs and costs of an intervention in each patient of a sample under study. This allows the same statistical principles commonly used in clinical trials to be applied to cost or cost-effectiveness data. The methodology described in this article would allow expression of cost-effectiveness ratios in the form of confidence intervals. The calculation of the cost-effectiveness ratio by means of a confidence interval may have important practical consequences, both in decision-making on the choice of 1 intervention versus another and in calculating the size of the sample necessary to identify statistically significant differences, from both clinical and economic points of view. CONCLUSIONS: The complementary use of confidence intervals and sensitivity analysis makes it possible to measure uncertainty related and unrelated to variability in sample data, allowing the decision to adopt 1 technology or another to be based on the most objective information available. Although several ethical and methodologic concerns remain to be addressed, this methodology may contribute to improving the more rational and efficient use of drugs.

Confidence Intervals↗
PubMedDate not supplied

EEG activity during cognitive performance in women.

EEG activity of 20 female volunteers was monopolarly recorded at P3, P4, C3 and C4 during four resting periods and three series of cognitive tasks: one analytic, one spatial and one demanding analytical and spatial processing or mixed task. Relative power and inter and intrahemispheric correlations were analysed. Beta relative power was significantly higher during the resting periods at the right parietal and the same pattern of asymmetry was maintained during the three series of tasks. Alpha relative power decreased and theta increased during the three series of tasks regardless of their cognitive nature as compared to baseline. Interhemispheric correlation for theta frequencies, and intrahemispheric correlation for the full band were significantly different during task solution. There were no significant differences between left and right intrahemispheric correlations.

Adolescent↗
PubMedDate not supplied

[Validation of the Spanish version of PRIME-MD: a procedure for diagnosing mental disorders in primary care].

INTRODUCTION: Psychiatric disorders occurs in at least 20% of patients attending Primary Care settings, however, only 50% of them are detected by primary care physicians. Therefore a tool is required which can help primary care physicians to detect and diagnose psychiatric disorders. PRIME-MD (Primary Care Evaluation of Mental Disorders) is a questionnaire designed with this aim. In this article the results of the validation study of the Spanish version of this questionnaire are presented. MATERIALS AND METHODS: 312 patients were interviewed by primary care physicians using PRIME-MD and by psychiatrists using SCAN (Schedules for Clinical Assessment in Neuropsychiatry). RESULTS: The time most frequently spent in questionnaire application by the physician was 10 minutes. PRIME-MD detected the presence of at least one psychiatric disorder in 44.3% of patients. PRIME-MD diagnoses agree well with SCAN diagnoses for mood disorders (coefficient of agreement: 0.50) and for anxiety disorders (coefficient of agreement: 0.35), but not for somatoform disorders or alcohol-related disorders. CONCLUSIONS: The Spanish version of PRIME-MD questionnaire in a useful tool to identify and diagnose mood and anxiety disorders in Primary Care settings.

Adolescent↗
PubMedDate not supplied

[Findings on magnetic resonance in spastic cerebral palsy].

OBJECTIVES: To study the types of lesion found on magnetic resonance (MR) in cerebral palsy (CP) and their correlation with a the type of CP, gestational age at birth and aetiology. PATIENTS AND METHODS: We made a retrospective review of all patients over one year in age, diagnosed as having spastic CP, who were seen in a paediatric neurology clinic between 1987 and 1998. The MR were evaluated blindly using data from the clinical history. RESULTS: Seventy two patients fulfilled criteria for inclusion in the study. The following results were obtained (all associations were statistically significant with p<0.01):1. Patterns of lesion: MR findings were classified into one of the following patterns: parasagittal lesion (7), diffuse multicystic encephalomalacia (4), periventricular leukomalacia (PVL) (26), bilateral dilatation of the basal ventricles without alteration of the signal from the periventricular white matter (5), bilateral lesions in the basal ganglia (5), focal multicystic encephalomalacia (limited to one vascular area) (4), unilateral lesions of hypersignal in the white matter (4), unilateral dilation of a lateral ventricle with or without homolateral cortical atrophy (3), malformations/disorders of migration (7), normal (7). 2. Correlation of the findings with the gestational age and type of CP: a) Spastic tetraplegia: 64% of the premature babies showed PVL. In newborn babies at term the lesions were more varied. b) Spastic diplegia: 80% of the premature babies had PVL and 83% of newborn babies at term had normal MR. c) Spastic hemiplegia: 81% had unilateral lesions. 3. Correlation with the aetiology: 62% of the cases of parasagittal lesions, diffuse multicystic encephalomalacia and bilateral lesions of the basal ganglia were due to hypoxic-ischemic encephalopathy. CONCLUSION: The MR findings in CP show good correlation with gestational age, type of CP and aetiology.

Basal Ganglia↗
PubMedDate not supplied

[Impairments in attention and facial emotion recognition in treatment of refractory and non refractory schizophrenics evaluated through an odd-ball paradigm].

INTRODUCTION: Some of the processes impaired in schizophrenia are attention and emotional recognition. The aim of this study was to test: 1) if refractory schizophrenics (RS) present higher attentional deficits than non refractory (NR) evaluated through performance and the P300 amplitude in an odd ball paradigm using letters as stimuli; 2) if emotional recognition deficits in schizophrenics can be reflected by means of a similar paradigm than that used for letters, especially in RS, and; 3) if there exist a correlation between P300 amplitude and the level of psychopathology in these patients. PATIENTS AND METHODS: Performance and P300 amplitude were measured during a letter (LE) task and a similar one of facial emotion recognition (ER) applicating an odd ball paradigm, on 10 normal controls (CO), 10 NR and 10 RS. RESULTS: Reaction time was longer in both tasks and in LE, P300 amplitude was lower in NR and RS than in CO. In ER the RS showed a lower number of correct responses and higher of omissions than NR and CO, correlated with neuroleptics doses. A negative correlation between P300 amplitude and the scores of BPRS and PANSS positive symptoms scale was only found for the NR in ER. CONCLUSIONS: Present results point out that RS show similar deficits in relation to attention as NR do, but they show major deficits in emotional recognition related with neuroleptics doses. Furthermore, a lower P300 amplitude for NR was related to a higher level of psychopathology only in EF.

Adult↗