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排序方式: 共有9821条查询结果,搜索用时 15 毫秒
91.
M Ferreira F Pinto A Macedo N Banazol C Franco M P Magalh?es M Lima 《Revista portuguesa de cardiologia》1992,11(1):37-43
STUDY OBJECTIVE: To determine the influence of echocardiography in the preoperative diagnosis of heart diseases in children. DESIGN: Retrospective study. SETTING: Hospitalized children admitted in Departments of Pediatric Cardiology and Cardiothoracic Surgery. PATIENTS: Children of both sexes, aged from neonate to 14 years old, with heart disease who underwent cardiac surgery. MATERIAL AND METHODS: From January 1989 to July 1990, 220 consecutive cardiac surgeries were performed in children with heart disease. The initial diagnosis was based on data from clinical examination, electrocardiogram, thorax X-Ray and echocardiogram (M-mode, 2D, conventional and colour Doppler). Patients were separated in three groups according to their ages: newborn infants less than 28 days old; infants less than 12 months old; children more than 1 year old and less than 14 years old. Patients were separated according to the investigations used further for preoperative diagnosis: whether they had or not cardiac catheterization performed prior to surgery. RESULTS: From 220 surgical interventions performed, 124 were "open heart" surgeries (9 neonates, 28 infants and 87 children) and the remaining had "closed heart" operations (14 neonates, 37 infants and 45 children). Preoperative diagnosis was mainly dependent on echocardiography, dispensing catheterization in 90 cardiac interventions. The diagnosis was confirmed at surgery or at autopsy. There were 9 deaths, 3 of which occurred in patients not submitted to cardiac catheterization. CONCLUSIONS: Echocardiography is a reliable method for investigation and establishment of the preoperative diagnosis of heart diseases in children. Its use may further reduce the need for diagnostic catheterization in children, particularly in risk groups. 相似文献
92.
93.
M F Lima e Costa R S Rocha M L Leite R G Carneiro D Colley G Gazzinelli N Katz 《Revista do Instituto de Medicina Tropical de S?o Paulo》1991,33(1):58-63
Associations between socio-demographic factors, water contact patterns and Schistosoma mansoni infection were investigated in 506 individuals (87% of inhabitants over 1 year of age) in an endemic area in Brazil (Divino), aiming at determining priorities for public health measures to prevent the infection. Those who eliminated S. mansoni eggs (n = 198) were compared to those without eggs in the stools (n = 308). The following explanatory variables were considered: age, sex, color, previous treatment with schistosomicide, place of birth, quality of the houses, water supply for the household, distance from houses to stream, and frequency and reasons for water contact. Factors found to be independently associated with the infection were age (10-19 and > or = 20 yrs old), and water contact for agricultural activities, fishing, and swimming or bathing (Adjusted relative odds = 5.0, 2.4, 3.2, 2.1 and 2.0, respectively). This suggests the need for public health measures to prevent the infection, emphasizing water contact for leisure and agricultural activities in this endemic area. 相似文献
94.
Sellers RS Luchin AI Richard V Brena RM Lima D Rosol TJ 《Journal of molecular endocrinology》2004,33(1):227-241
Parathyroid hormone-related protein (PTHrP) is a multifunctional protein that is often dysregulated in cancer. The human PTHrP gene is alternatively spliced into three isoforms, each with a unique 3'-untranslated region (3'-UTR), encoding 139, 173 and 141 amino acid proteins. The regulation of PTHrP mRNA isoform expression has not been completely elucidated, but it may be affected by transforming growth factor-beta1 (TGF-beta1). In this study, we examined differences in the PTHrP mRNA isoform expression in two squamous carcinoma cell lines (SCC2/88 and HARA), an immortalized keratinocyte cell line (HaCaT), and spontaneous human lung cancer with adjacent normal tissue. In addition, the effect of TGF-beta1 on PTHrP mRNA isoform expression and stability was examined. Cell-type specific expression of PTHrP mRNA isoforms occurred between the various cell lines, normal human lung, and immortalized human keratinocytes (HaCaT). PTHrP isoform expression pattern was significantly altered between normal lung tissue and the adjacent lung cancer. In vitro studies revealed that TGF-beta1 differentially altered the mRNA steady-state levels and mRNA stability of the PTHrP isoforms. Protein-RNA binding studies identified different proteins binding to the 3'-UTR of the PTHrP isoforms (139) and (141), which may be important in the differential mRNA stability and response to cytokines between the PTHrP isoforms. The data demonstrate that there is cell-type specific expression of PTHrP mRNA isoforms, and disruption of the normal regulation during cancer progression may in part be associated with TGF-beta1-induced changes in PTHrP mRNA isoform expression and stability. 相似文献
95.
High-dose chemoradiation therapy with autologous hematopoietic progenitor cell support is effective treatment for patients with a variety of high-risk malignancies. In this setting, tumor cell contamination of the hematopoietic progenitor cell product is a frequently observed problem. The malignant cells in the autograft may be a source of relapse after transplant. Purging the hematopoietic cell grafts ex-vivo may eradicate malignant cells that may contaminate the autologous product. This chapter describes the major purging strategies that have been investigated clinically over the past decade. This investigation includes negative purging with pharmacologic agents and monoclonal antibodies, positive selection with immunoadsorption, immunomagnetic and flow cytometric sorting techniques, ex-vivo culture method, treatment with cytotoxic T cells, and virally mediated purging methods. 相似文献
96.
Elevated C-reactive protein levels are associated with endothelial dysfunction in chronic cocaine users 总被引:1,自引:0,他引:1
Meng Q Lima JA Lai H Vlahov D Celentano DD Margolick JB Lai S 《International journal of cardiology》2003,88(2-3):191-198
OBJECTIVE: To examine the relationship of the serum C-reactive protein (CRP) and endothelial function and their associations with coronary artery calcification, lipid profile and cardiac changes. METHODS: The analyses for serum lipids and CRP, echocardiography, spiral computed tomography scans and endothelial function assay were performed in 53 participants with a history of chronic cocaine use. RESULTS: There were no statistically significant differences in demographic characteristics and drug use between CRP normal (<1.9 mg/l) and abnormal groups. The brachial artery diameter percentage changes in the third scan (immediately after deflation of cuff) and the fourth scan (90 s after deflation of cuff) were significantly associated with the CRP levels (the third: beta=-0.054, S.E.=0.027; P=0.028; the fourth: beta=-0.065, S.E.=0.026; P=0.016). The multiple regression models showed that CRP was the only significant predictor of artery diameter changes (%) in these two scans. The CRP abnormal group had more coronary artery calcification (calcium scores >5, 16.7 vs. 0%; P=0.036) and more cardiac diastolic dysfunction expressed as deceleration time >240 ms (16.7 vs. 0%; P=0.036). CONCLUSIONS: Elevated serum CRP levels are associated with endothelial dysfunction, coronary artery calcification and cardiac diastolic dysfunction in chronic cocaine users. 相似文献
97.
Dr. Michèle Gue BS Jean Fioramonti DS Jacques Frexinos MD M. Alvinerie BS Lionel Bueno DS 《Digestive diseases and sciences》1987,32(12):1411-1417
The effects of acoustic stress (AS) on gastrointestinal motility and their prevention by previous treatment with naloxone, phentolamine, propranolol, muscimol, and diazepam were investigated in intact and vagotomized fasted dogs fitted with chronically implanted strain gauges on the antrum at 10 cm from pylorus and on the jejunum at 70 and 140 cm from the pylorus. These effects were compared to those produced by intracerebroventricular administration of ovine corticotropin releasing factor (oCRF). Beginning 40–50 min after the occurrence of a gastric migrating motor complex (MMC), a 1-hr hearing of prerecorded intense music through earpieces (<100 dB) delayed the occurrence of the next gastric MMC observed after 2.8±1.2 hr, while jejunal MMC were still present at a normal frequency. During AS, heart rate and plasma cortisol were significantly increased by 32.7 and 215%, respectively, 10–15 min after the beginning of hearing. The AS-induced lengthening of the gastric MMC cycle as well as cortisol increase were abolished after previous administration of diazepam (0.5 mg/kg intramuscular) or muscimol (10 g/kg intravenous), while they were still present after naloxone (0.1 mg/kg intravenous), phentolamine (0.2 mg/kg intravenous), or propranolol (0.1 mg/kg intravenous). CRF administered intracerebroventricularly (100 ng/kg) also delayed the occurrence of gastric MMC without affecting jejunal motility, and this effect was not antagonized by previous treatment with diazepam or muscimol. Both the effects of AS and CRF were abolished after bilateral thoracic vagotomy. These results suggest that the selective inhibition of gastric motility induced by noise in dog is due to the CNS release of CRF which affects, in turn, the vagal output to the stomach. The suppressive action of diazepam or GABA agonist on noise-induced gastric hypomotility may be related to blockade of the AS-induced CRF release. 相似文献
98.
99.
Guilherme Silva Torrezan Carlos Roberto Polaquini Marcelo Freitas Lima Luis Octavio Regasini 《Sustainable Chemistry and Pharmacy》2020
Glycerol is the main co-product from biodiesel production and has been recognized as a sustainable solvent. Herein, we used glycerol and waste glycerol in synthesis of two bioactive α,β-unsaturated ketones (E,E)-1,5-diphenylpenta-2,4-dien-1-one (1) and (E,E)-2,6-dibenzylidenecyclohexanone (2), using aldol mono- and di-condensation reactions, respectively. Crude yield values were calculated from product mass after precipitation and drying. Purity was measured by High Performance Liquid Chromatography with Photodiode Array (HPLC-PAD) using analytical curves and reference compounds. Glycerol and waste glycerol were able to furnish 1 and 2 in higher crude yields and HPLC-PAD purities values than other protic solvents (ethanol, methanol, PEG-400 and water). In order to investigate reasons of glycerol efficiency when compared to water efficiency, we performed computational calculations using Density Functional Theory (DFT). Theoretical predictions confirmed the E1cB mechanism, as well as favourable energy barrier using glycerol in comparison to water, corroborating their sustainable properties. In addition, waste glycerol from corn and sunflower oil transesterifications were used in the synthesis of 1 and 2 for four recycles, displaying good crude yields and HPLC-purities. 相似文献
100.
Ricardo K. Kalil Altamir Monteiro Jr. Maria Isabel Lima Eni B. Silveira Francineide S. S. Foltran Carlos E. Speck Martins 《Ultrastructural pathology》2013,37(1):45-50
Macrophagic myofasciitis (MMF) is an inflammatory myopathy related to aluminum-containing vaccines. Described in 1998, most cases were reported in adults, with only 22 cases being reported in children. Three children aged between 13 months and 3½ years were investigated in our institution for neuromuscular symptoms. They underwent thorough clinical, familial, and laboratory investigations, electroneuromyography, muscle biopsy with transmission electron microscopy, scanning electron microscopy/energy dispersive spectroscopy (SEM/EDS), and, in one case, brain magnetic resonance imaging. They had received regular immunizations. Two patients were hypotonic and one presented with myotonia. Muscle biopsy of all patients presented macrophagic infiltrates with intracytoplasmic aluminum content as revealed by SEM/EDS analysis. Their diverse clinical picture does not support a direct relationship between local morphologic findings and systemic symptoms. The atypical clinical presentation of these children may not result from the superposition of MMF upon a background systemic neuromyopathy, suggesting instead that they are two coincident and independent conditions. Although the finding of macrophage infiltrates in muscle tissue is not new, the identification of aluminum content is recent. The use of tissue sections for aluminum detection and mapping by SEM/EDS is conclusive for, diagnosis; it has not been reported previously in a pathology journal, to the authors' knowledge. 相似文献