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排序方式: 共有525条查询结果,搜索用时 15 毫秒
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Joao Borges Fortes Filho Cristiano Koch Barros Gabriela Unchalo Eckert Leticia Procianoy Renato S Procianoy 《国际眼科》2008,1(2):143-147
AIM: To investigate the incidence of retinopathy of prematurity(ROP) in the southern Brazil, the rate of treatment and outcomes in all premature infants born at Hospital de Clinicas de Porto Alegre, Brazil, from October 2002 to October 2006.
· METHODS: A prospective cohort study was conducted on 323 premature children born at Hospital de Clinicas de Porto Alegre, Brazil, from October 2002 to October 2006 with birth weight equal to or less than 1 500g or a gestational age at birth of 32 weeks or less. All of the newborns were examined by indirect binocular ophthalmoscopy with the 28 diopters lens after pupil's dilation and a lid speculum after the sixth week of life with examinations repeated depending on the disease classification. The main clinical outcome was the occurrence of ROP at any stage.
· RESULTS: ROP occurred in 82 infants with an incidence rate of 25.7%. Threshold disease occurred in only 17 of the patients (5.3%), all of them had the disease affecting posterior Zone II needing laser treatment. None of the treated children had Zone I or aggressive posterior disease despite that three of the treated children needed a second laser session. One patient of the re-treated group needed scleral buckling with an equatorial silicon band after progression to stage 4 of ROP.
· CONCLUSION: The incidence of retinopathy and the threshold disease in this study was similar to the international results reported. This study showed a high survival rate (70.1%), high incidence of retinopathy, and high laser treatment necessity among newborns under 28 weeks of gestational age or under 1 000g of birth weight. This study drove attention about the no identification of any Zone I posterior disease in this cohort of patients. 相似文献
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Franco Mdo C Arruda RM Fortes ZB de Oliveira SF Carvalho MH Tostes RC Nigro D 《Journal of cardiovascular pharmacology》2002,39(3):369-377
Epidemiologic studies suggest that intrauterine undernutrition plays an important role in the development of arterial hypertension in adulthood. The aim of the current study was to evaluate whether severe nutritional restriction during pregnancy can aggravate hypertension, vascular reactivity changes, and renal development in spontaneously hypertensive rat (SHR) offspring. To investigate the potential existence of gender differences, both male and female offspring of pregnant SHRs on a restricted diet were studied in adulthood. Female pregnant SHRs were fed either normal or 50% of the normal intake diets, during the whole gestational period. Arterial blood pressure and nephron number were determined. Norepinephrine, acetylcholine, and sodium nitroprusside responses in isolated aortic rings from the offspring (male and female, when they reached adulthood) were also evaluated. In the SHR offspring (male and female) the intrauterine undernutrition further increased the blood pressure levels, increased the response to norepinephrine, and decreased the response to acetylcholine, without altering the response to sodium nitroprusside. In addition, it induced a decrease in the number of nephrons in the kidney from adult offspring. In conclusion, fetal undernutrition aggravates hypertension and the endothelial dysfunction along with an impairment of renal development in both male and female SHRs. 相似文献
25.
Franco Mdo C Dantas AP Akamine EH Kawamoto EM Fortes ZB Scavone C Tostes RC Carvalho MH Nigro D 《Journal of cardiovascular pharmacology》2002,40(4):501-509
Maternal undernutrition during critical periods of organ development is known to impair fetal growth and predispose to the development of adulthood diseases, such as hypertension, coronary heart disease and type II diabetes that are linked to low birth weight and are characterized by endothelial dysfunction. Increased oxidative stress, in rats submitted to intrauterine undernutrition, provides a potential explanation for the endothelial dysfunction development. The aim of this study was to determine the oxidative stress and its consequence on mesenteric arteriolar responses to vasoactive agents in offspring from diet-restricted dams. For this, female pregnant Wistar rats were fed either normal or 50% of normal intake diets, during the whole gestational period. In male offspring, arterial blood pressure was determined by the tail cuff method in anesthetized rats, mesenteric arteriolar reactivity and superoxide anion generation were studied using intravital microscopy and superoxide dismutase activity was determined in mesentery by spectrophotometric assay. Intrauterine undernutrition induced hypertension, decreased vasodilation to acetylcholine and bradykinin but did not alter the responses to sodium nitroprusside. Topical application of superoxide dismutase and superoxide dismutase mimetic manganese (III) tetrakis (1-methyl-4-pyridyl) porphyrin significantly improved the altered arteriolar responses to acetylcholine and bradykinin. A decreased superoxide dismutase activity and an increased superoxide anion concentration were observed in the offspring of diet-restricted dams. This study shows for the first time that intrauterine undernutrition enhances oxidative stress in vivo and relates this to the impaired endothelium-dependent vasodilation. 相似文献
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Viral respiratory infections in young children attending day care in urban Northeast Brazil 总被引:2,自引:0,他引:2
28.
Brennan P Fortes C Butler J Agudo A Benhamou S Darby S Gerken M Jökel KH Kreuzer M Mallone S Nyberg F Pohlabeln H Ferro G Boffetta P 《Cancer causes & control : CCC》2000,11(1):49-58
Objective: We have examined the role of dietary patterns and specific dietary nutrients in the etiology of lung cancer among non-smokers using a multicenter case–control study.Methods: 506 non-smoking incident lung cancer cases were identified in the eight centers along with 1045 non-smoking controls. Dietary habits were assessed using a quantitative food-frequency questionnaire administered by personal interview. Based on this information, measures of total carotenoids, beta-carotene and retinol nutrient intake were estimated.Results: Protective effects against lung cancer were observed for high consumption of tomatoes, (odds ratio (OR) = 0.5; 95% confidence interval (CI) 0.4–0.6), lettuce (OR = 0.6; 95% CI 0.3–1.2), carrots (OR = 0.8; 95% CI 0.5–1.1), margarine (OR = 0.7; 95% CI 0.5–0.8) and cheese (OR = 0.7; 95% CI 0.5–1.0). Only weak protective effects were observed for high consumption of all carotenoids (OR = 0.8; 95% CI 0.6–1.0), beta-carotene (OR=0.8; 95% CI 0.6–1.1) and retinol (OR = 0.9; 95% CI 0.7–1.1). Protective effects for high levels of fruit consumption were restricted to squamous cell carcinoma (OR = 0.7; 95% CI 0.4–1.2) and small cell carcinoma (OR = 0.7; 95% CI 0.4–1.2), and were not apparent for adenocarcinoma (OR = 0.9; 95% CI 0.6–1.3). Similarly, any excess risk associated with meat, butter and egg consumption was restricted to squamous and small cell carcinomas, but was not detected for adenocarcinomas.Conclusions: This evidence suggests that the public health significance of increasing vegetable consumption among the bottom third of the population would include a reduction in the incidence of lung cancer among lifetime non-smokers by at least 25%, and possibly more. A similar protective effect for increased fruit consumption may be present for squamous cell and small cell lung carcinomas. 相似文献
29.
Landgraf MA Martinez LL Rastelli VM Franco Mdo C Soto-Suazo M Tostes Rde C Carvalho MH Nigro D Fortes ZB 《The Journal of nutrition》2005,135(6):1480-1485
Experimental and epidemiologic data have shown that malnutrition predisposes individuals to infections. Immune responses are compromised, particularly in undernourished children. Therefore, we investigated the migratory capacity of leukocytes, using the intravital microscopy technique, in male Wistar rats (8-9 wk of age) that were undernourished in utero after their dams were fed 50% less food than the amount consumed by control dams. The number of leukocytes rolling along the venular endothelium, sticking after stimulation with leukotriene B4, tumor necrosis factor-alpha (TNF-alpha) or zymosan-activated plasma, or migrating after TNF-alpha stimulation was significantly reduced in the undernourished rat offspring. Compared with nourished rat offspring, undernourished offspring had significantly reduced numbers of circulating leukocytes, higher blood pressure, and higher leukocyte rolling velocity (V(WBC)), as well as a higher ratio between V(WBC) and RBC velocity (V(RBC)). Endothelial P-selectin and intercellular adhesion molecule-1 (ICAM-1) expression, analyzed by immunohistochemistry, and basal leukocyte L-selectin expression, analyzed by flow cytometry, were significantly reduced in the undernourished rat offspring. Because the groups did not differ in leukocyte CD11/18 expression, endothelial expression of platelet-endothelial cell adhesion molecule-1, or venular blood flow velocity and, consequently, venular shear rate, we conclude that intrauterine undernutrition in rats reduces leukocyte migration, downregulates endothelial expression of P-selectin and ICAM-1, as well as leukocyte expression of L-selectin, while reducing leukocyte counts. The higher V(WBC) and V(WBC)/V(RBC) ratio may also play a role in this reduced leukocyte migration. Our data suggest that this phenomenon is involved in the increased predisposition to infections in undernourished subjects. 相似文献
30.
Boccolini D Carrara GC Dia I Fortes F Cani PJ Costantini C 《The American journal of tropical medicine and hygiene》2005,73(6):1071-1076
The chromosomal polymorphism of Anopheles funestus sensu stricto from Angola was analyzed from indoor-resting samples collected in 11 peri-urban and rural sites of the Luanda and Huambo Provinces, which are > 450 km apart and have distinct eco-climatic conditions. Five polymorphic paracentric inversions were observed (scored chromatids range = 202 to 248): 2Ra, 2Rh, 3Ra, 3Rb, and 3La. Inversions 3Rb and 3La were highly polymorphic; the 2Ra and 3Ra arrangements were absent in Luanda. No significant departures from Hardy-Weinberg and linkage equilibria were found at the locality, commune, or province level (sites 相似文献