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排序方式: 共有2746条查询结果,搜索用时 31 毫秒
41.
Alice Rosi Pedro Mena Fabio Castello Daniele Del Rio 《International journal of food sciences and nutrition》2021,72(1):70-81
AbstractInformation on children’s diet including bioactive compounds is quite scarce. This observational study investigated the composition of the diet of children living in Parma (Italy; n?=?172, 8–10?years) using 3-day food records completed in winter and spring. Mean daily intakes of food groups, energy and nutrients were obtained using the national food database, while (poly)phenol contents were estimated from Phenol-Explorer or by specific literature searches. Food consumption, energy and nutrient intakes decreased in spring and were partially in line with national data. Adherence to the nutritional recommendations was not satisfied for the majority of nutrients. Main contributors to the phenolic intake were flavonoids (flavan-3-ols) and phenolic acids (hydroxycinnamic acids), while main dietary sources were fruit, chocolate-based products, vegetables, and tea & coffee (decaffeinated). This study provided the first comprehensive analysis of the nutritional composition of children’s diet. Future research should look at the health implications of dietary choices in children. 相似文献
42.
Espinet B Solé F Pedro C Garcia M Bellosillo B Salido M Florensa L Camacho FI Baró T Lloreta J Serrano S 《Human pathology》2005,36(11):1232-1237
Mantle cell lymphoma (MCL) is a B-cell neoplasm with a relatively aggressive clinical course. There is a very small subgroup of patients who present with atypical lymphocytes in peripheral blood, with or without lymphocytosis, lymphadenopathy, or splenomegaly, and with an indolent clinical course. They frequently show mutated IgV(H) genes and CD5 negativity. We report an asymptomatic elderly patient who presented with a single submandibular lymphadenopathy. The biopsy showed immunophenotype and t(11;14)(q13;q32) consistent with MCL. The abnormal lymphoid population was also detected in peripheral blood and bone marrow. The patient has remained asymptomatic for 5 years without receiving any therapy. It is uncertain whether these cases represent an early-stage event in the development or an indolent form of MCL. The existence of such asymptomatic patients with an indolent clinical course should induce a strict clinical judgment in terms of therapeutic decisions. 相似文献
43.
Raúl Mena Patricia Edwards Ofelia Pérez-Olvera Claude M. Wischik 《Acta neuropathologica》1995,89(1):50-56
This double-labelling confocal microscopy study of the neuropathology of Alzheimer's disease (AD) reports the use of a fluorescent dye, thiazin red, which has staining properties similar to thioflavin-S. Thiazin red fluorescence can be visualised selectively in the red channel, and we have used this property to compare it with the labelling seen using monoclonal antibody (mAb) 423, which detects tau protein C-terminally truncated at Glu-391, and mAb 4G8, which detects -amyloid protein. Thiazin red is shown to recognized the typical histopathological deposits associated with both proteins. However, not all deposits containing these proteins are stained. Specifically, diffuse -amyloid plaques and severely degraded extracellular tangles are unlabelled. Likewise a characteristic mAb 423-reactive granular plaque-like structure, typically present in cases with abundant extracellular tangels, is unlabelled by thiazin red. Such plaques can be shown to be continuous with the basal dendrites of degraded tanglebearing pyramidal cells. These findings suggest that paired helical filaments (PHFs) continue to undergo degradation in the extracellular space, which is associated with loss of thiazin red binding sites, but preservation of mAb 423 immunoreactivity. This epitope appears to be characteristic of a stable core element of the PHF which is highly resistant to proteolysis. Compounds such as thiazin red with high affinity for -pleated protein structures can be used to monitor the state of pathological assembly of amyloidogenic protein species found in AD.Supported in part by CONACyT grant #1624-N9208 (to R.M.), the Medical Research Council (U.K.), Zeneca Pharmaceuticals and the Alzheimer Disease Research Fund and the Leopold Muller Estate 相似文献
44.
J. Garcia de Yebenes Prous A. Carlsson M. A. Mena Gomez 《Naunyn-Schmiedeberg's archives of pharmacology》1978,304(2):95-99
Summary Taurine, a putative inhibitory neurotransmitter, was injected in various doses intracerebroventricularly to conscious rats via pre-implanted polythene cannulas. The formation of DOPA and 5-hydroxytryptophan (5-HTP) in various brain regions was investigated by measuring the accumulation of these monoamine precursors induced within 30 min by the intraperitoneal injection of 3-hydroxybenzyl hydrazine HCl (NSD 1015, 100 mg/kg), an inhibitor of the aromatic L-amino acid decarboxylase readily penetrating into the brain. DIPA formation, but not 5-HTP formation was significantly enhanced by taurine in dose-related manner in all brain regions studied, indicating an increased synthesis of both dopamine and noradrenaline. Dopamine depletion induced by -methyltyrosine was significantly retarded by taurine, whereas noradrenaline depletion tended to be enhanced. Endogenous levels of dopamine were increased, whereas the following brain constituents were unchanged: tyrosine, tryptophan, noradrenaline, 5-HT and 5-hydroxyindoleacetic acid. In the exoeriments with NSD 1015, a dose-related decrease in rectal temperature and in motility was observed after taurine treatment, as compared to treatment with the decarboxylase inhibotor alone. Systemic parenteral administration of taurine caused no significant changes in brain monoamines, body temperature or behaviour but decreased the heart noradrenaline levels. The data indicate that taurine, which apparently has to be given intracerebroventricularly in order to reach the brain in sufficient amounts, causes inhibition of firing in central dopamine neurons but has the opposite effect on noradrenaline neurons, perhaps also peripherally, whereas 5-HT neurons appear to be unaffected. In addition, taurine appears to interfere with motor behaviour and temperature regulation, possibly via effects on catecholaminergic systems. 相似文献
45.
Cerebral beta amyloid angiopathy is a risk factor for cerebral ischemic infarction. A case control study in human brain biopsies 总被引:5,自引:0,他引:5
Cadavid D Mena H Koeller K Frommelt RA 《Journal of neuropathology and experimental neurology》2000,59(9):768-773
Cerebral amyloid angiopathy (CAA) is conspicuous for its association with Alzheimer disease (AD) and as a cause of lobar hemorrhages in the elderly, but its role in cerebral infarction is less clear. There is evidence that CAA may also be a risk factor for ischemic infarction in AD. To further investigate CAA as a risk factor for infarction, we studied 108 cases of recent cerebral or cerebellar infarction diagnosed in tissue samples obtained from surgical material. There were 69 males and 39 females with a mean age of 52 yr (range 1-86). The majority of biopsies were obtained from the frontal and parietal lobes. Radiological studies demonstrated a lesion confined to a vascular distribution in 12 of the 17 (71%) cases examined. Microscopic sections stained with hematoxylin and eosin revealed complete, organizing infarction in 107 cases with areas of coagulative necrosis, anoxic-ischemic neuronal injury, inflammation, macrophages, vascular proliferation, gliosis, and swollen axons. One case showed an incomplete infarct. Most cases also exhibited a minor hemorrhagic component with hemosiderin and hematoidin pigments. CAA, defined as amyloid deposition in the walls of leptomeningeal and parenchymal arteries, was found by immunohistochemical stains for beta amyloid in 14 (13%) cases of complete cerebral infarct. Cortical beta amyloid plaques were found by immunohistochemistry in 19 (17%) cases. Cerebral or cerebellar tissues containing cortex and leptomeninges obtained from 136 patients with a mean age of 52 yr (range 1-85) during surgical procedures for diagnosis of primary or metastatic neoplasms and demyelinating lesions were used as age-matched controls. In this control group, CAA was found in 5 (3.7%) and beta amyloid plaques in 19 (14%). The results indicate that CAA, but not beta amyloid plaque formation, is significantly more common in patients with ischemic cerebral infarction than in age-matched controls with nonvascular lesions (odds ratio 3.8; 95% confidence interval 1.3-10.9; p < 0.01). Our results indicate that CAA is a risk factor for ischemic cerebral infarction in the population studied. 相似文献
46.
47.
Guglielmo Nasti Renato Talamini Andrea Antinori Ferdinando Martellotta Gaia Jacchetti Francesco Chiodo Giuseppe Ballardini Laura Stoppini Giovanni Di Perri Maurizio Mena Marcello Tavio Emanuela Vaccher Antonella D'Arminio Monforte Umberto Tirelli 《Journal of clinical oncology》2003,21(15):2876-2882
PURPOSE: To assess potential new prognostic factors and to validate the AIDS Clinical Trials Group (ACTG) for AIDS-related Kaposi's sarcoma (AIDS-KS) staging system in the highly active antiretroviral therapy (HAART) era. PATIENTS AND METHODS: We collected epidemiologic, clinical, staging, and survival data from 211 patients with AIDS-KS enrolled in two prospective Italian human immunodeficiency virus (HIV) cohort studies. We included in the analysis all patients with the diagnosis of KS made from January 1996, the time at which HAART became available in Italy. RESULTS: In the univariate analysis, survival was not influenced by sex, age, level of HIV viremia at KS diagnosis, HAART at KS diagnosis (HAART-na?ve v HAART-experienced), or type of HAART combination. Regarding ACTG classification, the 3-year survival rate was 85% for T0 patients and 69% for T1 patients (P =.007), 83% for S0 patients and 63% for S1 patients (P =.003), and 83% for I0 patients and 71% for I1 patients (P =.06). In the multivariate analysis, only the combination of poor tumor stage (T1) and poor systemic disease (S1) risk identified patients with unfavorable prognosis. The 3-year survival rate of patients with T1S1 was 53%, which was significantly lower compared with the 3-year survival rates of patients with T0S0, T1S0, and T0S1, which were 88%, 80%, and 81%, respectively (P =.0001). CONCLUSION: In the era of HAART, a refinement of the original ACTG staging system is needed. CD4 level does not seem to provide prognostic information. Two different risk categories are identified: a good risk (T0S0, T1S0, T0S1) and a poor risk (T1S1). 相似文献
48.
Fernando Chaves Jesus García-Martínez Sonia de Miguel Francisca Sanz Joaquín R Otero 《Infection control and hospital epidemiology》2005,26(2):150-156
OBJECTIVES: To describe the relative proportions of nosocomial and community-onset Staphylococcus aureus bacteremia at our institution and the epidemiologic characteristics and clonal diversity of S. aureus isolates, as determined by pulsed-field gel electrophoresis (PFGE) and antimicrobial resistance patterns. DESIGN: Retrospective cohort study of all cases of S. aureus bacteremia between October 2001 and October 2002. SETTING: A 1300-bed, tertiary-care hospital. RESULTS: One hundred sixty-two unique episodes of S. aureus bacteremia were identified. Forty-three cases (26.5%) were caused by methicillin-resistant S. aureus (MRSA). Most cases of S. aureus bacteremia, whether MRSA or methicillin susceptible (MSSA), were nosocomial in origin (77.2%) or were otherwise associated with the healthcare system (16%). Only 11 (6.8%) of the cases (all MSSA) were strictly community acquired. Thirty-five unique macrorestriction patterns were identified among the 154 isolates that were typed by PFGE. Four major genotypes were defined among the isolates of MRSA, with 36 (85.7%) represented by a single PFGE type. Of the isolates within this major clone, all (100%) were ciprofloxacin resistant and 77.8% were erythromycin resistant. In contrast, the 112 isolates of MSSA comprised 31 different PFGE types, 3 of which represented 42.9% of all MSSA isolates and were associated with both nosocomial and community-onset bacteremia. CONCLUSIONS: Most cases of S. aureus bacteremia in our healthcare region are nosocomial in origin or are acquired through contact with the healthcare system and are thus potentially preventable. To preclude dissemination of pathogenic clones, it is therefore necessary to redouble preventive measures in both the hospital and the community. 相似文献
49.
Neurotrophic factors are compounds that enhance neuronal survival and differentiation. Most of these compounds exert their pharmacological actions on selective types of neurons, and therefore, are considered promising new therapeutic agents for the treatment of different neurodegenerative disorders characterized by selective degeneration of certain neuronal groups. Those compounds have been used in humans for several neurological disorders including amyotrophic lateral sclerosis--ciliary derived neurotrophic factor (CNTF) and brain derived neurotrophic factor (BDNF), Alzheimer's disease and peripheral neuropathy--nerve growth factor (NGF) and Parkinson's disease (PD)--glial derived neurotrophic factor (GDNF). In spite of well founded clinical experiments by previous experimental work in animal models some of these trials have been negative. For instance, animal models of PD have shown that several neurotrophic factors, including GDNF and other compounds, reduce apoptosis and increase resistance of dopamine neurons to neurotoxins in vitro. These compounds prevent or recover the damage to dopamine neurons of rodents and primates produced by chemical or mechanical acute lesions including 6-OH-DA, MPTP, methamphetamine and axotomy. The differences between the promising results obtained in experimental models and the lack of clinical results or excessive toxicity found in humans could be attributed to the following reasons: (a) Lack of relevance between the pathogenesis of the experimental lesion and the corresponding neurodegenerative disorder. (b) Poor correlation between results obtained in acute, self-limited, selective deficit produced to experimental animals and those available in more complex, chronic and progressive disorders involving patients. (c) Inadequate delivery of the active product to the target area in the human brain. (d) Poor information from acute experiments in animals which does not predict long-term effects of chronic infusion in humans. Further experimental work, therefore, is needed to transfer these neurotrophic factors to the clinic. 相似文献
50.
Maria Carmen Iglesias-Osma Sandy Bour Maria Jose Garcia-Barrado Virgile Visentin Maria Francisca Pastor Xavier Testar Luc Marti Gemma Enrique-Tarancon Philippe Valet Julio Moratinos Christian Carpn 《Pharmacological research》2005,52(6):21-484
It has been reported that benzylamine reduces blood glucose in rabbits, stimulates hexose uptake, and inhibits lipolysis in mouse, rabbit, and human adipocytes. In the presence of vanadate, benzylamine is also able to improve glucose disposal in normoglycaemic and diabetic rats. Such insulin-mimicking properties are the consequence of hydrogen peroxide production during benzylamine oxidation by semicarbazide-sensitive amine oxidase (SSAO). The aim of the study was to determine whether other SSAO-substrates could share such potential antidiabetic properties. Thus, mafenide, a synthetic antimicrobial sulfonamide structurally related to benzylamine, and which has been recently reported to interact with SSAO, was tested in the above mentioned models, in parallel with methylamine, a proposed endogenous SSAO-substrate. All tested amines stimulated glucose uptake and inhibited lipolysis in rat and mouse fat cells. Methylamine and benzylamine, but not mafenide, reduced the hyperglycaemic response during a glucose tolerance test in rabbits while the three amines tested were devoid of insulin-releasing activity under both in vivo and in vitro conditions. In human adipocytes, mafenide did not stimulate glucose transport since it was not a high-affinity substrate for SSAO and generated less hydrogen peroxide than benzylamine or methylamine. Therefore, mafenide could not be considered as an antidiabetic drug despite being oxidized and exhibiting insulin-mimicking effects in rat and mouse adipocytes. By contrast, the endogenous substrate methylamine improved glucose utilization in all in vitro and in vivo models, leading to consider novel SSAO substrates as drugs with potential anti-hyperglycaemic properties. 相似文献