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991.
OBJECTIVE: To assess the ability of 1993 WHO-ISH recommendations to identify patients who need drug treatment. METHODS: 268 hypertensive patients with suspected mild hypertension were preselected for this study at their first visit at the referral center. 123 were included after a short in-hospital work-up when they fulfilled the 1993 WHO-ISH criteria for mild hypertension (90-105 mmHg diastolic BP and/or 140-180 mmHg systolic BP). Echocardiography was performed in all patients by the same investigator according to ASE convention. The combined 10-year risk of stroke and coronary heart disease was calculated with the Framingham equation. Patients were then followed up for six months by the same physician blinded to echographic results and risk calculations and applying the WHO-ISH guidelines (monthly BP measurement and subjective assessment of risk). Five patients were excluded, for reasons unrelated to the protocol. RESULTS: The decision of drug treatment was taken at the 1st, 2nd, 3rd, 4th, 5th, 6th monthly visit after work-up in 2, 6, 25, 7, 2 and 6 patients, respectively. Among these 118 patients, 48 patients (29 male, 19 female) were eventually treated and 70 (49 male, 30 female) remained untreated. BP s at preselection and on a day of work-up were similar in both groups. Patients in whom drug treatment was prescribed were older and had higher lef ventricular mass (LVM) than untreated patients, but only 2 of them (all in the treated group) had LVM values above usual thresholds (LVM > 125 g/m2, in men and women). Stroke and coronary risks were both higher in treated than in untreated patients (p < 0.05). The physician using the guidelines decided to treat only 19 of the 38 patients with a 10-year risk < 10% (true positive), whereas she decided to treat with drugs 12 patients among the 44 with a 10-year risk < 5%. CONCLUSION: The difference in LVM between untreated and treated patients support the validity of the WHO-ISH guidelines, but the measurement of LVM did not bring much information for managing the individual patient. Application of these guidelines did not satisfactorily identify high risk patients and could lead to over-treatment of low risk patients.  相似文献   
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994.
INTRODUCTION AND OBJECTIVE: The syndrome of deficient attention and hyperactivity affects approximately 5% of children of school age. Clinically it is characterized by deficient attention, impulsiveness and excessive motor activity. Developments in nonlinear dynamic theory have made it possible to think of modelling cerebral activity as a dynamic system of chaotic type. One the most widely standardized measurements is the dimension of correlation (D2). In this paper we study the electroencephalographic traces of a control group of 9 healthy children and another group of 19 children with the syndrome of deficient attention, at rest and whilst carrying out a visuomotor task (Test of perception of differences). MATERIAL AND METHODS: The dimension of correlation was estimated for both groups. Statistical comparison was made between the cortical distributions of the D2 between both types of recordings and between both groups. RESULTS: The children with lack of attention showed a larger number of activated cortical areas than those of the control group when carrying out the same task. However, during the resting state there were no differences in the D2 between the control children and the children with deficient attention. The indicates that both groups have the same basal level of activation. CONCLUSION: The dimension of correlation is a method which permits the demonstration of an increase in neuronal activity in the stimulated areas, in this case in the occipital region.  相似文献   
995.
We compared the performance of patients with frontal excisions, patients with temporal excisions and controls in tasks involving speeded choice responses in which a number of variables were manipulated including: perceptual difficulty, stimulus and response set-size, associative complexity, and spatial stimulus-response compatibility. Response times were sensitive to all manipulations but did not show any group differences. The error rates of the three groups were equally affected by perceptual difficulty and response set-size but frontals were preferentially affected by spatial S-R compatibility, associative complexity, and the number of stimuli per response. The results are consistent with a basic deficit in response selection processes which could underly many problems produced by frontal lesions.  相似文献   
996.
One hundred and fifty-five strains of Aeromonas isolated in the stools of children under 5 years presenting with acute diarrheal disease were studied. Using the Aerokey II system for the identification of species, 47 strains were identified as Aeromonas caviae, 58 as Aeromonas hydrophila, 23 as Aeromonas veronii biovar sobria, 14 as Aeromonas trota, 9 as Aeromonas veronii biovar veronii, 2 as Aeromonas jandaei and 2 as Aeromonas shubertii, Emphasis is placed on the advantages of this method which allowed for the classification of new species not identified previously in our country.  相似文献   
997.
In a pilot study to establish fetal nucleated red blood cell (NRBC) detection in maternal blood, trisomy 13 was diagnosed by FISH analysis at 11 weeks' gestation. The NRBCs were detected after a single-step ficoll density gradient enrichment. In blood samples taken both before and after CVS, 52 and 80 NRBCs, respectively, were found to be positive for fetal haemoglobin. In 47 per cent of these cells, FISH analysis for X and Y chromosomes confirmed the fetal sex. Moreover, 48 per cent of these NRBCs showed three fluorescent signals for a chromosome 13 probe, which confirmed the diagnosis of trisomy 13, previously detected at CVS karyotyping. This is the first report of non-invasive prenatal diagnosis of trisomy 13, i.e., pre-CVS, in the first trimester. The high number of fetal NRBCs detected indicates a connection with aneuploidy, probably due to early impairment of the feto-maternal barrier.  相似文献   
998.
999.
The essential oil of Lippia multiflora was prepared by hydrodistillation of leaves and stalks and characterized by GC and mass spectroscopy. The oil was tested for antimalarial activity on in vitro cultures of Plasmodium falciparum (FcB1-Columbia chloroquine-resistant strain and F32-Tanzania chloroquine-sensitive strain). The dilutions inhibiting the in vitro growth of the parasite by 50% 24 and 72 hr after administration of the essential oil to the parasite culture were 1/12,000 and 1/21,000, respectively. When tested on a highly synchronized culture, the essential oil inhibited growth mostly at the trophozoite-schizont step, indicating a potential effect on the first nuclear division of the parasite.  相似文献   
1000.
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