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101.
Epstein JN Willoughby M Valencia EY Tonev ST Abikoff HB Arnold LE Hinshaw SP 《Journal of consulting and clinical psychology》2005,73(3):424-434
Significant ethnic differences have been consistently documented on attention-deficit/hyperactivity disorder (ADHD) teacher rating scales. Whether these ethnic differences result from a teacher rating bias or reflect actual classroom behavior patterns is unknown. Ethnic differences between Caucasian and African American (AA) elementary schoolchildren on teacher ratings and codings of observed classroom behavior were examined with latent variables. In structural equation models, correlations between teacher ratings and observed classroom behavior suggested nonbiased teacher ratings of AA schoolchildren with diagnosed ADHD. Ethnic differences were documented for both teacher ratings of ADHD and classroom behavior. Differences in classroom behavior were attenuated when the behavior of an average child in the classroom was taken into account. Multiple explanations for this pattern of results are discussed. 相似文献
102.
103.
Ramírez-López E Grijalva-Haro MI Valencia ME Antonio Ponce J Artalejo E 《Salud pública de México》2005,47(2):126-133
OBJECTIVE: To determine the effect of a School Breakfast Program on obesity and some cardiovascular risk factors in 6 to 10 year old schoolchildren. MATERIAL AND METHODS: A quasi-experimental prospective study was conducted in 2002-2003, in 17 municipalities of Sonora State, Mexico. The intervention group consisted of 254 children participating in a School Breakfast Program (SBP group). The control group (NSBP group, n=106) included children who did not participate in the program. In both groups the body mass index for age (BMI/age) and body composition by electrical resistance using bioelectrical bioimpedance analysis (BIA) were estimated at the beginning and at the end of a 9-month period. In a subgroup of 264 school-children (SBP and NSBP children), serum cholesterol, triglycerides and fasting glucose were measured at the start and at the end of the program. RESULTS: The body mass index in the SBP and NSBP groups was not different at the start or at the end of the school period (p>0.05). The proportion of overweight and obese children and the percentage fat remained similar in both groups. However, the lean mass increased (p>0.05) at the end of the school period in both groups, and hence, cannot be attributed to the program. The biochemical parameters showed no change (p>0.05) in blood glucose, total serum cholesterol, and triglycerides in either group at the end of the school period. CONCLUSIONS: Study results showed no evidence of a negative effect of SBP in terms of risk factors for obesity and cardiovascular disease. 相似文献
104.
In 1989, we described a new autosomic-recessive myelin-mutant rat that develops a progressive motor syndrome characterized by tremor, ataxia, immobility episodes (IEs), epilepsy, and paralysis. taiep is the acronym of these symptoms. The rat developed a hypomyelination, followed by demyelination. At an age of 7-8 months, taiep rats developed IEs, characterized electroencephalographically by REM sleep-like cortical activity. In our study, we analyzed the ontogeny of gripping-induced IEs between 5 and 18 months, their dependence to light-dark changes, sexual dimorphism, and susceptibility to mild stress. Our results showed that IEs start at an age of 6.5 months, with a peak frequency between 8.5 and 9.5 months. IEs have two peaks, one in the morning (0800-1000 h) and a second peak in the middle of the night (2300-0100 h). Spontaneous IEs showed an even distribution with a mean of 3 IEs every 2 h. IEs are sexually dimorphic being more common in male rats. The IEs can be induced by gripping the rat by the tail or the thorax, but most of the IEs were produced by gripping the tail. Mild stress produced by i.p. injection of physiological saline significantly decreased IEs.These results suggested that IEs are dependent on several biological variables, which are caused by hypomyelination, followed by demyelization, which causes alterations in the brainstem and hypothalamic mechanisms responsible for the sleep-wake cycle regulation, producing emergence of REM sleep-like behavior during awake periods. 相似文献
105.
Ahumada M Cabadés A Valencia J Cebrián J Payá E Morillas P Sogorb F Francés M Cardona J Guardiola F;Investigadores del registro PRIMVAC 《Revista espa?ola de cardiología》2005,58(1):13-19
INTRODUCTION AND OBJECTIVES: The clinical profile of patients with acute myocardial infarction (AMI) who have reinfarction (REAMI) during their stay in the intensive cardiologic care unit (ICCU) is not well known. The aim of this study was to identify factors predictive of REAMI, as well as its global incidence and mortality. PATIENTS AND METHOD: All patients with AMI admitted to the ICCU of 17 hospitals in the Comunidad de Valencia (Spain) in the period 1995-2000 (PRIMVAC Registry) were included. Differential characteristics between patients with or without REAMI were determined, and odds ratios (OR) for possible predictive factors were estimated with their 95% confidence intervals by logistic regression. RESULTS: A total of 12,071 patients were included. Mean age of the patients was of 65.5 years, the percentage of women was 23.8%, and the incidence of REAMI was 2.8%. The REAMI group was significantly older than the non-REAMI group. Female sex was significantly more common in the REAMI group. More diagnostic and therapeutic procedures were carried out, more drugs were used and there were more complications in the REAMI group. Mortality was significantly higher in the REAMI group (37.8% vs 12.6%). Only age, diabetes mellitus, previous myocardial infarction and the appearance of Q waves in the electrocardiogram were independently associated with the presence of REAMI. CONCLUSIONS: REAMI in the ICCU was associated with high mortality. Some clinical factors present during the first few hours after AMI were associated independently with the appearance of REAMI. 相似文献
106.
Large-scale comparative genomics meta-analysis of Campylobacter jejuni isolates reveals low level of genome plasticity 下载免费PDF全文
Taboada EN Acedillo RR Carrillo CD Findlay WA Medeiros DT Mykytczuk OL Roberts MJ Valencia CA Farber JM Nash JH 《Journal of clinical microbiology》2004,42(10):4566-4576
We have used comparative genomic hybridization (CGH) on a full-genome Campylobacter jejuni microarray to examine genome-wide gene conservation patterns among 51 strains isolated from food and clinical sources. These data have been integrated with data from three previous C. jejuni CGH studies to perform a meta-analysis that included 97 strains from the four separate data sets. Although many genes were found to be divergent across multiple strains (n = 350), many genes (n = 249) were uniquely variable in single strains. Thus, the strains in each data set comprise strains with a unique genetic diversity not found in the strains in the other data sets. Despite the large increase in the collective number of variable C. jejuni genes (n = 599) found in the meta-analysis data set, nearly half of these (n = 276) mapped to previously defined variable loci, and it therefore appears that large regions of the C. jejuni genome are genetically stable. A detailed analysis of the microarray data revealed that divergent genes could be differentiated on the basis of the amplitudes of their differential microarray signals. Of 599 variable genes, 122 could be classified as highly divergent on the basis of CGH data. Nearly all highly divergent genes (117 of 122) had divergent neighbors and showed high levels of intraspecies variability. The approach outlined here has enabled us to distinguish global trends of gene conservation in C. jejuni and has enabled us to define this group of genes as a robust set of variable markers that can become the cornerstone of a new generation of genotyping methods that use genome-wide C. jejuni gene variability data. 相似文献
107.
Vargiu P De Abajo R Garcia-Ranea JA Valencia A Santisteban P Crespo P Bernal J 《Oncogene》2004,23(2):559-568
The Ras homolog enriched in striatum, Rhes, is the product of a thyroid hormone-regulated gene during brain development. Rhes and the dexamethasone-induced Dexras1 define a novel distinct subfamily of proteins within the Ras family, characterized by an extended variable domain in the carboxyl terminal region. We have carried this study because there is a complete lack of knowledge on Rhes signaling. We show that in PC12 cells, Rhes is targeted to the plasma membrane by farnesylation. We demonstrate that about 30% of the native Rhes protein is bound to GTP and this proportion is unaltered by typical Ras family nucleotide exchange factors. However, Rhes is not transforming in murine fibroblasts. We have also examined the role of Rhes in cell signaling. Rhes does not stimulate the ERK pathway. By contrast, it binds to and activates PI3K. On the other hand, we demonstrate that Rhes impairs the activation of the cAMP/PKA pathway by thyroid-stimulating hormone, and by an activated beta2 adrenergic receptor by a mechanism that suggests uncoupling of the receptor to its cognate heterotrimeric complex. Overall, our results provide the initial insights into the role in signal transduction of this novel Ras family member. 相似文献
108.
García-Benayas T Blanco F Martín-Carbonero L Valencia E Barrios A González-Lahoz J Soriano V 《AIDS research and human retroviruses》2003,19(9):739-741
Thirty-four HIV-positive men with gynecomastia were seen in an HIV outclinic during a 20-month period (incidence of 2.4 cases/100 patients receiving HAART per year). It developed mainly in subjects having good immunologic and virologic status, after an average of 3 years of HAART. No hormone abnormalities were found, or association with specific drugs. Although initially unilateral, more than half of cases progressed to bilateral gynecomastia. Spontaneous resolution occurred in most subjects with 12 months without modifying therapy. 相似文献
109.
Belvis R Marti-Fàbregas J Franquet E Cocho D Valencia C Martí-Vilalta JL 《Neurología (Barcelona, Spain)》2003,18(3):170-174
Brain areas involved in heart autonomic control are not well characterized. Insulae have been proposed as control centers. A lesion in these areas may induce a cardiac autonomic dysfunction (arrhythmias, atrioventricular conduction abnormalities). Asystolia has not been previously reported. A 65-year-old man suffered an acute ischemia of the right middle cerebral artery (MCA) territory. NIHSS score was 19 points. Brain CT scan was normal. Transcranial Doppler (TCD) showed occlusion of the right MCA. Fibrinolysis was initiated 135 minutes after stroke onset with TCD monitoring. Twenty minutes later he suffered cardiac arrest with asystolia trace in the ECG monitor. Fibrinolysis was stopped during resuscitation. Four minutes later, he recovered with the same NIHSS score. Aggressive resuscitation maneuvers were not necessary. A repeated brain CT scan showed infarct signs in the whole MCA territory and a new TCD did not show any change. Serial blood analyses including cardiac nzymes were normal. The patient experienced four brief cardiac arrests in the next nine hours, so a temporary cardiac pacemaker was placed for four days. He was treated with aspirin and was discharged 14 days after admission. He has not experienced recurrences during a 6-month follow-up. We could not diagnose the etiology of the cardiac arrests. All the episodes occurred in the acute stroke stage and arrhythmia, atrioventricular block, myocardial ischemia or structural lesions were not found in the cardiac study. We propose that ischemia in the right insula induced sudden and transitory interruptions of the sympathetic cardiac tone. 相似文献
110.
Krolczyk S Pacheco E Valencia P Papazian O Yelin K Alfonso I 《Journal of child neurology》2003,18(5):356-358
Preferential involvement of certain central nervous systems areas by specific viruses provides a valuable guide to the selection of antiviral agents. We report a neonate that developed opsoclonus 7 days prior to the diagnosis of herpes simplex type 2 cerebellitis. The course of the opsoclonus paralleled the clinical course and radiologic evolution of the infection. The purpose of this report is to describe opsoclonus as a possible early sign of herpes simplex type 2 central nervous system infection. 相似文献