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991.
Martínez-González MA Fernández-Jarne E Serrano-Martínez M Marti A Martinez JA Martín-Moreno JM 《European journal of nutrition》2002,41(4):153-160
Summary.
Background: Although an important secondary prevention trial reported an impressive protection by a Mediterranean dietary pattern on
reinfarction and cardiovascular death, scarce direct epidemiologic evidence is currently available regarding the role of the
Mediterranean diet in the aetiology of coronary heart disease. Aims: The aim of the study was to quantify the risk reduction of incident myocardial infarction provided by a Mediterranean dietary pattern. Methods: We included 342 subjects (171 patients who suffered their first acute myocardial infarction and 171 matched controls) in
a case-control study. A validated semi-quantitative food frequency questionnaire (136 items) was used. We defined an a priori Mediterranean dietary pattern. We assessed six food items that we considered protective: 1) olive oil, 2) fiber, 3) fruits,
4)vegetables, 5) fish and 6) alcohol. For each of these six dietary factors, we calculated the distribution according to quintiles
within the study and assigned each participant a score of 1 to 5 corresponding to the quintile of intake, with 1 representing
the lowest and 5 representing the highest quintile. We also estimated the quintiles of two other elements assumed to be associated
with a higher risk: 7) meat/meat products and 8) some items with high glycaemic load (white bread, pasta and rice). For these
two elements we inversely ranked the score, with 1 representing the highest and 5 representing the lowest quintile. Finally,
we summed up the eight quintile values for each participant.
A second score (post hoc pattern) was built using only a single cut-off point for these eight elements. The cut-off points for each element in this
post hoc pattern were decided according to the dose-response relationships between the consumption of each food item and the risk
of myocardial infarction observed in the analyses that used quintiles of each food item. Results: For both patterns, we found that the higher the score, the lower the odds ratio of myocardial infarction. A significant linear
trend was apparent after adjustment for the main cardiovascular risk factors. For each additional point in the a priori Mediterranean pattern (observed range: 9–38) the odds ratio (95 % confidence intervals) was 0.92 (0.86–0.98). This estimate
was 0.55 (0.42–0.73) when we used the post hoc pattern (range: 0–8). Conclusions: Our data support the hypothesis that a Mediterranean diet (that emphasizes olive oil, fiber, fruits, vegetables, fish and
alcohol and reduces meat/meat products) can be an effective measure for reducing the risk of myocardial infarction. However,
our results support the exclusion of refined cereals with a high glycaemic load as healthy elements of this pattern.
Received: 24 January 2002, Accepted: 13 May 2002 相似文献
992.
993.
994.
Badia X Mearin F Balboa A Baró E Caldwell E Cucala M Díaz-Rubio M Fueyo A Ponce J Roset M Talley NJ 《PharmacoEconomics》2002,20(11):749-758
OBJECTIVES: To evaluate the burden of illness in irritable bowel syndrome (IBS), in terms of resource utilisation (direct and indirect) and health-related quality of life (HR-QOL), in individuals with IBS who meet Rome I and Rome II criteria. METHODS: A cross-sectional study, carried out by personal interview, on a representative sample (n = 2000) of the Spanish population. Individuals with suspected IBS were identified via a screening question and subsequently given an epidemiological questionnaire to complete. The questionnaire collected information on IBS symptoms, resource utilisation, and HR-QOL [Medical Outcomes Study 36-item Short Form (SF-36)]. RESULTS: Sixty-five individuals met Rome II criteria for IBS, while 146 individuals met exclusively Rome I criteria. Of Rome II individuals, 67.7% had consulted some type of healthcare professional in the previous 12 months, compared with only 41.8% of those individuals meeting exclusively Rome I criteria (p vs 17.1%); 'drug consumption' (70.8 vs 45.2%); and 'reduced performance in main activity' (60 vs 27.4%). Compared with the general population, the study sample reported significantly worse HR-QOL scores in four dimensions of the SF-36 ('bodily pain', 'vitality', 'social functioning' and 'role-emotional'. Additionally, individuals meeting Rome II criteria reported worse HR-QOL scores than those individuals meeting exclusively Rome I criteria, especially in the 'bodily pain' and 'general health' dimensions. CONCLUSIONS: The burden of illness in IBS is important and correlated to the diagnostic criteria employed. Individuals who met Rome II criteria reported a higher level of resource utilisation and worse HR-QOL than individuals meeting exclusively Rome I criteria. 相似文献
995.
996.
Pérez-Rodríguez E Jiménez D Díaz G Pérez-Walton I Luque M Guillén C Mañas E Yusen RD 《Archives of internal medicine》2003,163(22):2766-2770
BACKGROUND: Prolonged air travel and the associated immobilization are risk factors for venous thromboembolism. The occurrence of pulmonary thromboembolism (PTE) under these circumstances is referred to as economy class syndrome. We assessed the incidence of symptomatic PTE in passengers on long-haul flights arriving at Madrid-Barajas Airport, Madrid, Spain, and the association with the number of flight hours. METHODS: We retrospectively reviewed cases of PTE among international travelers arriving at Madrid-Barajas Airport between January 1995 and December 2000. Patients presenting with symptoms of deep venous thrombosis but without symptoms of PTE were excluded. Pulmonary thromboembolism was identified using an algorithm of diagnostic tests. The incidence of PTE and the association with flight duration was assessed. RESULTS: The average number of passengers per year who arrived at the airport on flights originating abroad in the period analyzed was 6 839 222. Sixteen cases of PTE were detected over the 6-year period. All patients with travel-associated PTE had flight durations of greater than 6 hours. The overall incidence of PTE was 0.39 per 1 million passengers (95% confidence interval [CI], 0.20-0.58). On flights that lasted between 6 and 8 hours, the incidence was 0.25 per 1 million passengers (95% CI, 0-0.75), while on flights longer than 8 hours, the incidence was 1.65 per 1 million passengers (95% CI, 0.81-2.49) (P<.001). CONCLUSIONS: Air travel is a risk factor for PTE, and the incidence of PTE increases with the duration of the air travel. However, the low incidence of PTE among long-distance passengers, similar to that observed in other international airports, does not justify social alarm. 相似文献
997.
Long-term treatment with insulin induces apoptosis in brown adipocytes: role of oxidative stress 总被引:4,自引:0,他引:4
Porras A Zuluaga S Valladares A Alvarez AM Herrera B Fabregat I Benito M 《Endocrinology》2003,144(12):5390-5401
Trying to define the precise role played by insulin regulating the survival of brown adipocytes, we have used rat fetal brown adipocytes maintained in primary culture. The effect of insulin on apoptosis and the mechanisms involved were assessed. Different from the known effects of insulin as a survival factor, we have found that long-term treatment (72 h) with insulin induces apoptosis in rat fetal brown adipocytes. This process is dependent on the phosphatidylinositol 3-kinase/mammalian target of rapamycin/p70 S6 kinase pathway. Short-term treatment with the conditioned medium from brown adipocytes treated with insulin for 72 h mimicked the apoptotic effect of insulin. During the process, caspase 8 activation, Bid cleavage, cytochrome c release, and activation of caspases 9 and 3 are sequentially produced. Treatment with the caspase inhibitor, benzyloxycarbonyl-Val-Ala-Asp (Z-VAD), prevents activation of this apoptotic cascade. The antioxidants, ascorbic acid and superoxide dismutase, also impair this process of apoptosis. Moreover, generation of reactive oxygen species (ROS), probably through reduced nicotinamide adenine dinucleotide phosphate oxidases, and a late decrease in reduced glutathione content are produced. According to this, antioxidants prevent caspase 8 activation and Bid cleavage, suggesting that ROS production is an important event mediating this process of apoptosis. However, the participation of uncoupling protein-1, -2, and -3 regulating ROS is unclear because their levels remain unchanged upon insulin treatment for 72 h. Our data suggest that the prolonged hyperinsulinemia might cause insulin resistance through the loss of brown adipose tissue. 相似文献
998.
Correa-Rovelo JM Tellez O Obregón L Duque-López X Miranda-Gómez A Pichardo-Bahena R Mendez M Moran S 《Diseases of the colon and rectum》2003,46(7):955-962
PURPOSE The purpose of the study was to determine the variables associated with postoperative pain and the clinical response of patients with uncomplicated hemorrhoidal disease treated with stapled rectal mucosectomy in the medium term.METHODS Patients with Grade II to IV, uncomplicated hemorrhoidal disease who underwent stapled rectal mucosectomy were prospectively included. The basal characteristics of the population were evaluated and level of stapling and placement of hemostatic suture determined. Histologically, the type of resected epithelium and presence of muscle fibers was evaluated. Postoperative pain was evaluated by means of a visual analog scale. Complications and clinical response were evaluated.RESULTS One hundred patients with a mean age of 43.9 years were included. Only columnar epithelium was resected in 48, transitional epithelium in 47, and squamous epithelium in 5 patients. Smooth muscle fragments were found in 55 patients, and, in 12 of these, fibers from the external muscular layer of rectum were also seen. Follow-up was 12.6 +/- 3.4 (range, 7-24) months. A total of 79 patients were completely asymptomatic at the end of follow-up. Resected squamous epithelium was associated with a higher postoperative pain level in the multivariate analysis (coefficient beta = 1.16 (95 percent confidence interval, 0.08-2.24); P = 0.035).CONCLUSIONS Rectal mucosectomy with stapler is an effective method for the treatment of uncomplicated prolapsing hemorrhoidal disease. Intensity of postoperative pain was associated with the type of resected epithelium. This suggests that low transection of hemorrhoids must be avoided. 相似文献
999.
Enriched environment delays the onset of hippocampal damage after global cerebral ischemia in rats 总被引:3,自引:0,他引:3
Belayev A Saul I Liu Y Zhao W Ginsberg MD Valdes MA Busto R Belayev L 《Brain research》2003,980(1):121-127
An enriched environment has been shown to improve cognitive, behavioral and histopathological outcome after focal cerebral ischemia and head trauma. The purpose of this study was to determine the effect of an enriched environment on histopathology following global cerebral ischemia. Wistar rats (21 weeks of age) were placed in different environments [standard cages (SC) or enriched environment (EE) cages] for 2 months before and either 6 days or 2 months after ischemia. Rats underwent 10 min of global ischemia by bilateral carotid artery occlusions plus hypotension. Five groups (n=4-5 in each group) were studied: (1) rats kept in SC before and 2 months after ischemia; (2) rats kept in SC before ischemia but transferred to an EE for 2 months after ischemia; (3) rats kept in EE before and after ischemia for 2 months; (4) rats kept in SC before and 6 days after ischemia; (5) rats kept in EE before and 6 days after ischemia. At 7 days or 2 months after ischemia, brains were perfusion-fixed, and ischemic injury was assessed by counting numbers of normal neurons in the hippocampal CA1 sector. Physiological variables showed no inter-group differences. Rats housed in EE for 2 months before and for 6 days (but not 2 months) after global ischemia showed significantly better preservation of pyramidal neurons in the hippocampal CA1 area when compared to control animals (middle CA1, 20.5+/-5.4 vs. 2.8+/-0.6; lateral CA1, 31.5+/-7.2 vs. 2.6+/-0.6, respectively). The present data suggest that housing in EE for 2 months before and 6 days after ischemia can delay the onset of damage to hippocampal pyramidal neurons, which eventually occurs despite 2-month EE. 相似文献
1000.
Barber H Carreiras M 《Cortex; a journal devoted to the study of the nervous system and behavior》2003,39(3):465-482
The aim of the current study was to explore the integration processes of gender and number morphological features, since it has been proposed that grammatical gender and number features might be associated with different strength with the word stem in lexical representation. Event related potentials (ERPs) were recorded using a 128-channel sensor net while twenty-four volunteers read Spanish word pairs and performed a syntactic judgment task. The word pairs which could agree or disagree in gender or number or in gender and number at the same time, were formed by a noun and an adjective (e.g. faro-alto [lighthouse-high]). A negativity around 400 msec with posterior distribution, which has been related to lexical integration processes, was found in response to both gender and number violations. No differences were found between gender disagreement, number disagreement and the double disagreement. Therefore, ERPs suggest that integration of gender and number features may not be different, and that the detection of disagreement may work under a binary state, since the double disagreement condition did not differ from the others. In addition, a subsequent component (identified as P3) showed delayed latencies in the gender disagreement condition as compared to the number disagreement condition, while the double disagreement conditions showed a shorter peak latency than the other two disagreement conditions and similar to the agreement condition. The variations in the latency of the P3 component, which has been related to categorization processes, suggest that these processes are quickly triggered by the accumulation of two incongruent as compared to one disagreement features, and that reanalysis is costlier in the case of gender disagreement as compared to the number disagreement. 相似文献