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排序方式: 共有2620条查询结果,搜索用时 15 毫秒
1.
A. Prado Rodríguez R. Mato Búa L. Mera Mujico J. Arca Suárez M. López Sánchez L. Sampayo Rodríguez P. Rama-Maceiras 《Revista espa?ola de anestesiología y reanimación》2021,68(6):361-366
Serum lactate is a non-specific marker of tissue hypoperfusion. Elevated serum lactate is used in the differential diagnosis of acute intestinal ischemia. Although this practice is controversial, in the absence of other validated markers lactate is still used because of its high sensitivity.We present the cases of two patients who developed acute mesenteric ischemia as a post-surgical complication. The patients reported moderate abdominal pain —a non-specific symptom in the postoperative context— and tests showed progressively increasing serum lactate levels, which facilitated suspicion and subsequent diagnostic confirmation through an imaging test.These cases highlight the physiopathological importance of lactate elevation in the perioperative context and of performing a differential diagnosis of its possible causes, including mesenteric ischemia. Although the outcome was negative in the first case, early suspicion allowed us to make an effective diagnosis and administer appropriate treatment in the second patient. 相似文献
2.
Luana Lopes Padilha Elcio Oliveira Vianna Andressa Talícia Machado Vale Joelma Ximenes Prado Teixeira Nascimento Antônio Augusto Moura da Silva Cecilia Claudia Costa Ribeiro 《Pediatric allergy and immunology》2020,31(5):480-488
Studies on the exposure of children to sugar-sweetened beverages (SSBs) at an early age may contribute to better understand the common causes and the temporal order of the relationships between obesity and asthma in early childhood. The objective of this study was to estimate the association between SSB and child asthma traits in the 2nd year of life, modeling direct and indirect pathways mediated by the highest BMI-z of the child and allergic inflammation. Data from the BRISA cohort, São Luís-MA, Brazil (n = 1140), were obtained from the baseline and from the follow-up performed at the 2nd year of life. The main explanatory variable was the calories from added sugars in SSBs as a percentage of the total daily energy intake. The outcome child asthma traits was a latent variable deduced from four indicators: medical diagnosis of asthma, wheezing, emergency visit due to intense wheezing, and medical diagnosis of rhinitis. A high percentage of daily calories from sugars added to SSBs was directly associated with higher values of child asthma traits (standardized coefficient (SC = 0.073; P = .030)). High levels of eosinophils were also directly associated with child asthma traits (SC = 0.118; P = .049). No mediation pathways were observed via greater BMI-z or eosinophil counts. Therefore, early exposure of children to SSB may contribute to increased risk of childhood asthma, preceding the link between sugar consumption and overweight/obesity, not yet evident in children in the first 2 years of life. 相似文献
3.
Agma J. M. Tbaina Afonso H. M. A. Prado Josiane M. Bueno 《Journal of medical systems》1997,21(6):353-367
This paper presents a full reconstruction process of magnetic resonance images. The first step is to bring the acquired data from the frequency domain, using a Fast Fourier Transform algorithm. A Tomographic Image Interpolation is then used to transform a sequence of tomographic slices in an isotropic volume data set, a process also called 3D Reconstruction. This work describes an automatic method whose interpolation stage is based on a previous matching stage using Delaunay Triangulation. The reconstruction approach uses an extrapolation procedure that permits appropriate treatment of the boundaries of the object under analysis. 相似文献
4.
Pantin Hilda Coatsworth J. Douglas Feaster Daniel J. Newman Frederick L. Briones Ervin Prado Guillermo Schwartz Seth J. Szapocznik José 《Prevention science》2003,4(3):189-201
This paper reports a test of the efficacy of Familias Unidas, a Hispanic-specific, ecologically focused, parent-centered preventive intervention, in promoting protection against and reducing risk for adolescent behavior problems. Specifically, the intervention was designed to foster parental investment, reduce adolescent behavior problems, and promote adolescent school bonding/academic achievement, all protective factors against drug abuse and delinquency. One-hundred sixty seven Hispanic families of 6th and 7th grade students from three South Florida public schools were stratified by grade within school and randomly assigned to intervention and no-intervention control conditions. Results indicated that Familias Unidas was efficacious in increasing parental investment and decreasing adolescent behavior problems, but that it did not significantly impact adolescent school bonding/academic achievement. Summer-vacation rates of adolescent behavior problems were six times higher in the control condition than in the intervention condition. Furthermore, change in parental investment during the intervention was predictive of subsequent levels of adolescent behavior problems. The findings suggest that Familias Unidas is efficacious in promoting protection and reducing risk for adolescent problem behaviors in poor immigrant Hispanic families. 相似文献
5.
Hyperglycemia reduces the extent of cerebral infarction in rats 总被引:6,自引:0,他引:6
M D Ginsberg R Prado W D Dietrich R Busto B D Watson 《Stroke; a journal of cerebral circulation》1987,18(3):570-574
Although hyperglycemia is known to exacerbate neuronal injury in the setting of reversible brain ischemia, its effect on irreversible thrombotic infarction is less well understood. In this study, unilateral thrombotic infarction was induced photochemically in the parietal cortex of Wistar rats. Seven days later, brains were perfusion-fixed for light microscopy. Infarct areas were measured by computer-assisted planimetry on multiple coronal sections at 250-micron intervals; these data were integrated to yield infarct volumes. Fasted, normoglycemic rats were compared with hyperglycemic rats that had received 1.2-1.5 ml of 50% dextrose i.p. 15 minutes prior to the induction of infarction. Infarct volume averaged 12.5 +/- 4.0 mm3 (mean +/- SD) in rats (n = 14) with plasma glucose levels of 72-184 mg/dl; this differed statistically from the average volume of 9.3 +/- 3.3 mm3 observed in rats (n = 13) with elevated plasma glucose (range 264-607 mg/dl). Spearman rank correlation analysis confirmed a significant correlation of larger infarct volumes with lower plasma glucose levels. In contrast, rats receiving mannitol i.p. to produce an osmotic load comparable with that of the dextrose-pretreated animals showed larger infarct volumes than saline-treated controls. The small but definite beneficial effect of hyperglycemia in this end-arteriolar thrombotic infarction model is possibly attributable to improved local energy metabolism at the periphery of the lesion during the early period of lesion expansion. 相似文献
6.
7.
Clonidine tablets have been used in the past for treatment of spasticity with some success. The use of clonidine, however, has been limited by adverse effects, mainly hypotension. Over a two-year period, 17 patients were started on clonidine transdermal delivery system. They were followed for up to 18 months. Twelve of the 17 patients had a beneficial response and have continued on the patch. In ten of these 12 patients, other antispasticity drugs were either reduced or discontinued. In another three of the 17 patients, the response was good, but the patch was discontinued. No patient demonstrated persistent problematic hypotension. Clonidine Transdermal Patch appears to be an effective treatment for spasticity after a spinal cord injury. Adverse effects appear to be minimized using this mode of delivery. 相似文献
8.
A new model of embolic stroke produced by photochemical injury to the carotid artery in the rat 总被引:2,自引:0,他引:2
N Futrell B D Watson W D Dietrich R Prado C Millikan M D Ginsberg 《Annals of neurology》1988,23(3):251-257
We report a new model of embolic stroke in the rat, based on endothelial disruption and platelet aggregation in the carotid artery, which leads to distal embolization and focal brain infarction. The common carotid artery was irradiated for 6.5 minutes with the focused beam of an argon laser operated at a wavelength of 514.5 nm with a peak power of 2 W and an average power of 400 mw. Ipsilateral cerebral infarcts, ranging in size from 0.1 to 1.7 mm, were produced by platelet emboli in 12 of 13 rats. A total of 44 infarcts were observed in the 12 rats: 29 in the cortex, 6 in the hippocampus, 5 in the thalamus, and 4 in the basal ganglia. Scanning electron microscopy identified platelet aggregates in the carotid artery and in a deep cortical arteriole 50 minutes after the photochemical lesion. Twenty-four hours after the experiment, scanning electron microscopy of the carotid artery revealed damaged endothelium but few remaining adherent platelets. More intense laser irradiation in 8 rats, leading to carotid occlusion, produced an infarct in only 1. This new model can be used to study the acute and chronic pathological changes in the brain associated with platelet embolism. 相似文献
9.
M Guerrero Fernández J L Alfonso Sánchez B Sanchís Noguera M J Prado del Ba?o 《Gaceta sanitaria / S.E.S.P.A.S》1992,6(29):62-66
Data are presented on hospital stay for the population 65 years-old and over, measured in percentage over the total for Spain, for the 1978 to 1988 period, by gender, for each province and autonomous region (Comunidad Autónoma). The country's total for the last available year was 35%. Except in Baleares and Murcia, the proportion of hospital stays increased in all Regions, especially in Navarra, where it increased from 23% to 51%. After adjusting for age, the increase in the proportion of hospital stays in the study population was due to an increase in utilization per person. The proportion, which was 13.3% in 1978, raised to 23.8% in 1988, with an adjusted value of 21.3%. 相似文献
10.
International proficiency study of a consensus L1 PCR assay for the detection and typing of human papillomavirus DNA: evaluation of accuracy and intralaboratory and interlaboratory agreement 总被引:6,自引:0,他引:6
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Kornegay JR Roger M Davies PO Shepard AP Guerrero NA Lloveras B Evans D Coutlée F 《Journal of clinical microbiology》2003,41(3):1080-1086
The PGMY L1 consensus primer pair combined with the line blot assay allows the detection of 27 genital human papillomavirus (HPV) genotypes. We conducted an intralaboratory and interlaboratory agreement study to assess the accuracy and reproducibility of PCR for HPV DNA detection and typing using the PGMY primers and typing amplicons with the line blot (PGMY-LB) assay. A test panel of 109 samples consisting of 29 HPV-negative (10 buffer controls and 19 genital samples) and 80 HPV-positive samples (60 genital samples and 20 controls with small or large amounts of HPV DNA plasmids) were tested blindly in triplicate by three laboratories. Intralaboratory agreement ranged from 86 to 98% for HPV DNA detection. PGMY-LB assay results for samples with a low copy number of HPV DNA were less reproducible. The rate of intralaboratory agreement excluding negative results for HPV typing ranged from 78 to 96%. Interlaboratory reliability for HPV DNA positivity and HPV typing was very good, with levels of agreement of >95% and kappa values of >0.87. Again, low-copy-number samples were more prone to generating discrepant results. The accuracy varied from 91 to 100% for HPV DNA positivity and from 90 to 100% for HPV typing. HPV testing can thus be accomplished reliably with PCR by using a standardized written protocol and quality-controlled reagents. The use of validated HPV DNA detection and typing assays demonstrating excellent interlaboratory agreement will allow investigators to better compare results between epidemiological studies. 相似文献