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排序方式: 共有1381条查询结果,搜索用时 15 毫秒
91.
de Freitas V da Silva Porto P Assunção M Cadete-Leite A Andrade JP Paula-Barbosa MM 《Alcohol and alcoholism (Oxford, Oxfordshire)》2004,39(4):303-311
Aims: In a previous study, we found that prolonged oxidativestress produced by chronic ethanol consumption leads to an increasedformation of lipofuscin in hippocampal and cerebellar neurons.This pigment is an end-result of lipid peroxidation. Flavanols,which abound in the human diet, are known to exert a powerfulin-vitro antioxidant action. Therefore, to evaluate whetherthese compounds might display beneficial effects in the ratbrain, we examined whether or not these natural antioxidantswould impede neuronal ethanol-induced lipofuscin accumulation.Methods: Adult rats were fed for 6 months either with 20% ethanolsolution or with the same solution to which a mixture of grapeseed catechins and oligomeric procyanidins (200 mg/l) was added.Controls ingested either tap water or water supplemented withthe antioxidant compound. The total amount of lipofuscin inthe hippocampal CA1 and CA3 pyramids and in the cerebellar Purkinjecells was estimated by applying unbiased stereological methods.The mean volume of the neurons was estimated using the nucleatorand the volumetric density of lipofuscin was calculated by pointcounting. Results: Flavanols prevented the accumulation of neuronallipofuscin in the animals submitted to ethanol feeding (i.e.under conditions of increased oxidative stress) but not in thewater-drinking controls. The neuronal volume did not alter amongthe groups studied. Conclusions: Data obtained show that consumptionof flavanols can reduce the effects of oxidative activity broughtabout by alcohol consumption, indicating that these compoundsmight display neuronal beneficial effects under oxidative stress. 相似文献
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STUDY OBJECTIVE: Intravenous N-acetylcysteine has been used as an antidote for acetaminophen poisoning for more than 25 years in Europe and Canada. In the United States, only the oral administration of N-acetylcysteine is approved by the US Food and Drug Administration. Many physicians routinely use the inhalant preparation as an intravenous formulation; however, no stability, microbiology, or pyrogen studies have been performed. In this study, we evaluate the stability and microbiology of inhalational N-acetylcysteine compounded as an intravenous formulation. METHODS: A total of 8 N-acetylcysteine solutions (solution A through H) were prepared by injecting 150 mL of 20% solution through a 22-microm filter to 1 L of 5% dextrose (D(5)W; 2.6% solution). Solutions A through C were prepared at ambient conditions (25 degrees C [77 degrees F], 65% relative humidity), and solution D was prepared at accelerated conditions (40 degrees C [104 degrees F], 75% relative humidity) for stability testing. The assays were performed by means of high-performance liquid chromatography at 0, 4, 8, 12, 24, 36, 48, 60, and 72 hours according to US Pharmacopeia XXIV methodology. Solutions E through G were assessed for bacterial growth, and solution H underwent pyrogen testing by using a Limulus amebocyte lysate method. RESULTS: Solutions A through C remained stable for at least 60 hours (<10% decomposition), but at 72 hours, there was a 10.3%, 14.9%, and 13.4% degradation, respectively. Under accelerated conditions (solution D), stability lasted for more than 72 hours. Solutions E through G remained free from bacterial growth at 72 hours, and solution H tested negative for endotoxins-pyrogens. CONCLUSION: Inhalational N-acetylcysteine prepared as an intravenous solution meets US Pharmacopeia standards for stability up to 60 hours and is free from bacteria and their byproducts, offering a viable alternative to the traditional use of oral N-acetylcysteine. 相似文献
95.
Amadeu TP Coulomb B Desmouliere A Costa AM 《The international journal of lower extremity wounds》2003,2(2):60-68
Wound healing is an interactive, dynamic 3-phased process. During the formation of granulation tissue, many fibroblastic cells acquire some morphological and biochemical smooth muscle features and are called myofibroblasts. Myofibroblasts participate in both granulation tissue formation and remodeling phases. Excessive scarring, which is a feature of impaired healing, is a serious health problem that may affect the patient's quality of life. The treatment costs of such lesions are high, and often, the results are unsatisfactory. To understand the wound healing process better and to promote improvement in human healing, models are needed that can predict the in vivo situation in humans. In vitro models allow the study of cell behavior in a controlled environment. Such modeling partitions and reduces to small scales behavior perceived in vivo. This article is focused on "fibroblasts". In vitro models to study wound healing, the role of (myo)fibroblasts, and skin reconstruction in tissue replacement and promotion of wound healing are discussed. 相似文献
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The inter-rater reliability of the Brazilian version of the Recent Life Events Interview, developed by Paykel in order to evaluate stressful life events, was studied in 21 psychiatric inpatients and 20 psychiatric outpatients. Data concerning the agreement between the two raters showed a satisfactory reliability for specific occurrence of events, month of occurrence, independence of events and negative objective impact. This preliminary study suggests that the Brazilian version of the Recent Life Events Interview is a reliable instrument for the assessment of life events in Brazilian samples. 相似文献
98.
Rod-cone interactions: developmental and clinical significance 总被引:3,自引:0,他引:3
Mohand-Said S Hicks D Léveillard T Picaud S Porto F Sahel JA 《Progress in retinal and eye research》2001,20(4):451-467
During the last decade, numerous research reports have considerably improved our knowledge about the physiopathology of retinal degenerations. Three non-mutually exclusive general areas dealing with therapeutic approaches have been proposed; gene therapy, pharmacology and retinal transplantations. The first approach involving correction of the initial mutation, will need a great deal of time and further development before becoming a therapeutic tool in human clinical practice. The observation that cone photoreceptors, even those seemingly unaffected by any described anomaly, die secondarily to rod disappearance related to mutations expressed specifically in the latter, led us to study the interactions between these two photoreceptor populations to search for possible causal links between rod degeneration and cone death. These in vivo and in vitro studies suggest that paracrine interactions between both cell types exist and that rods are necessary for continued cone survival. Since the role of cones in visual perception is essential, pending the identification of the factors mediating these interactions underway, rod replacement by transplantation and/or neuroprotection by trophic factors or alternative pharmacological means appear as promising approaches for limiting secondary cone loss in currently untreatable blinding conditions. 相似文献
99.
Amoroso A Del Porto F Garzia P Ilardi M Clemenzia C D'Amato A Montesani C Rossi Fanelli F 《European review for medical and pharmacological sciences》1999,3(3):111-114
The coexistence of both kidney and colon primary malignancies is a rare condition. We report the case of a 75-year-old woman who presented with bilateral pulmonary nodules at chest X-ray and stratigraphy. Total-body CT scan showed multiple, apparently metastatic, bilateral pulmonary lesions, a diffusely dysomogeneous neoformation in the lower pole of the right kidney and a gross neoformation in the ascending colon. A right nephrectomy and a right hemicolectomy were performed and histology showed two primary neoplasms: clear cell renal carcinoma and undifferentiated adenocarcinoma of the colon. 相似文献
100.
Del Porto F Mariotti A Ilardi M Messina FR Afeltra A Amoroso A 《European review for medical and pharmacological sciences》1999,3(4):149-153
Vascular Endothelial Growth Factor (VEGF) plays a crucial role in the establishment of the vascular tree pattern. New vessels can be formed by two different ways; in the development of kidney both vasculogenesis and angiogenesis participate to microvessel assembly. VEGF and its receptor (VEGF-R) are co-expressed during kidney organogenesis and stimulate renal blood vessels development, induce and maintain the fenestrated phenotype in endothelium and regulate vascular permeability. VEGF and many other growth factors participate to the development of embryonic glomerular microvasculature. We believe that therapeutical use of VEGF or anti-VEGF antibodies may be performed in the treatment of many disorders. 相似文献