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排序方式: 共有195条查询结果,搜索用时 15 毫秒
81.
Outstanding progress regarding the pathophysiology of Crohn's disease (CD) has led to the development of innovative therapeutic concepts. Numerous controlled trials have been performed in CD. This review concentrates on the results of randomized, placebo-controlled trials, and meta-analyses when available, that provide the highest degree of evidence. Current guidelines on the management of CD recommend a step-up approach to treatment involving the addition of more powerful therapies as the severity of disease and refractoriness to therapy increase. The advent of biological drugs has opened new therapeutic horizons for treating CD, modifying the treatment goals. However, the large majority of patients with CD will be managed through conventional therapy, even if they are a prelude to biological therapy.  相似文献   
82.
Outstanding progress regarding the pathophysiology of Crohn’s disease (CD) has led to the development of innovative therapeutic concepts. Numerous controlled trials have been performed in CD. This review concentrates on the results of randomized,placebo-controlled trials,and meta-analyses when available,that provide the highest degree of evidence. Current guidelines on the management of CD recommend a step-up approach to treatment involving the addition of more powerful therapies as the severity of disease ...  相似文献   
83.
Tomato consumption does not affect the total antioxidant capacity of plasma   总被引:3,自引:0,他引:3  
This study was performed to evaluate the effect of tomato intake on total antioxidant activity of plasma measured by the radical trapping antioxidant parameter assay in 11 healthy female subjects. After 7 d of a diet low in carotenoids and free from lycopene, subjects ate 25 g tomato puree daily (containing 7.0 mg lycopene and 0.25 mg beta-carotene) for 14 consecutive days. At the beginning and end of tomato supplementation, the carotenoid plasma concentration and the total antioxidant activity of plasma were assessed. Before tomato puree consumption, mean +/- SE total lycopene and beta-carotene plasma concentrations were 0.13 +/- 0.02 micromol/L and 0.24 +/- 0.04 micromol/L, respectively. After tomato puree supplementation, both concentrations increased significantly (0.57 +/- 0.06 micromol/L, P < 0.0001 for total lycopene, and 0.31 +/- 0. 04 micromol/L, P = 0.0036 for beta-carotene); however, total plasma antioxidant capacity values did not change significantly. From our results, intake of a food rich in carotenoids does not seem to modify the antioxidant capacity of plasma as evaluated by the radical trapping antioxidant parameter assay.  相似文献   
84.
Photosynthetic oxygen production by photosystem II (PSII) is responsible for the maintenance of aerobic life on earth. The production of oxygen occurs at the PSII oxygen-evolving complex (OEC), which contains a tetranuclear manganese (Mn) cluster. Photo-induced electron transfer events in the reaction center lead to the accumulation of oxidizing equivalents on the OEC. Four sequential photooxidation reactions are required for oxygen production. The oxidizing complex cycles among five oxidation states, called the S(n) states, where n refers to the number of oxidizing equivalents stored. Oxygen release occurs during the S(3)-to-S(0) transition from an unstable intermediate, known as the S(4) state. In this report, we present data providing evidence for the production of an intermediate during each S state transition. These protein-derived intermediates are produced on the microsecond to millisecond time scale and are detected by time-resolved vibrational spectroscopy on the microsecond time scale. Our results suggest that a protein-derived conformational change or proton transfer reaction precedes Mn redox reactions during the S(2)-to-S(3) and S(3)-to-S(0) transitions.  相似文献   
85.
A debate is ongoing on the significance and appropriateness of the NOVA classification as a tool for categorizing foods based on their degree of processing. As such, the role of ultra-processed food (UPF) on human health is still not completely understood. With this review, we aimed to investigate the actual level of consumption of UPF across countries and target populations to determine the impact in real contexts. Suitable articles published up to March 2021 were sourced through the PubMed and SCOPUS databases. Overall, 99 studies providing data on the level of UPF consumption expressed as the percentage of total energy intake were identified, for a total of 1,378,454 participants. Most of them were published in Brazil (n = 38) and the United States (n = 15), and the 24 h recall was the most-used tool (n = 63). Analysis of the results revealed that the United States and the United Kingdom were the countries with the highest percent energy intake from UPF (generally >50%), whereas Italy had the lowest levels (about 10%); the latter was inversely associated with adherence to the Mediterranean diet. High variability was also observed based on sex, age, and body mass index, with men, young people, and overweight/obese subjects generally having higher levels of consumption compared to older subjects. Overall, our findings underline the large differences in UPF intake. Since most of the observations derived from studies conducted with food questionnaires are not specifically validated for UPF, further efforts are essential to confirm the results previously obtained and to investigate further the association between UPF consumption and health status, also considering the actual contribution within different dietary patterns, which has been less investigated to date.  相似文献   
86.
The aim of this study was to histopathologically examine the reaction of the connective tissue of rats to 2 calcium hydroxide-based sealers, Acroseal and Sealapex. Dentin tubes containing the materials and empty control tubes were implanted into the dorsal connective tissue of 36 Wistar albino rats. The animals were killed after 7 or 30 days, and the specimens were prepared for histologic analysis with hematoxylin and eosin, Von Kossa technique, and polarized light. Results were statistically analyzed using Kruskal-Wallis test. Both materials caused mild or moderate inflammatory reactions on the 7th day, but these reactions decreased by the 30th day with no significant difference at any time (P > .05). Mineralization of the subcutaneous tissue of the rats was observed only with Sealapex.  相似文献   
87.
Phytochemicals may protect cellular DNA by direct antioxidant effect or modulation of the DNA repair activity. We investigated the repair activity towards oxidised DNA in human mononuclear blood cells (MNBC) in two placebo-controlled antioxidant intervention studies as follows: (1) well-nourished subjects who ingested 600 g fruits and vegetables, or tablets containing the equivalent amount of vitamins and minerals, for 24 d; (2) poorly nourished male smokers who ingested 500 mg vitamin C/d as slow- or plain-release formulations together with 182 mg vitamin E/d for 4 weeks. The mean baseline levels of DNA repair incisions were 65.2 (95 % CI 60.4, 70.0) and 86.1 (95 % CI 76.2, 99.9) among the male smokers and well-nourished subjects, respectively. The male smokers also had high baseline levels of oxidised guanines in MNBC. After supplementation, only the male smokers supplemented with slow-release vitamin C tablets had increased DNA repair activity (27 (95 % CI 12, 41) % higher incision activity). These subjects also benefited from the supplementation by reduced levels of oxidised guanines in MNBC. In conclusion, nutritional status, DNA repair activity and DNA damage are linked, and beneficial effects of antioxidants might only be observed among poorly nourished subjects with high levels of oxidised DNA damage and low repair activity.  相似文献   
88.
Cardiovascular diseases, still the leading cause of mortality in the world, are closely related to vascular function. Older subjects are more susceptible to endothelial dysfunction and therefore it is important to define possible preventive or support strategies, such as consumption of foods with health-promoting effects. This systematic review aims to summarize the currently available evidence on acute or chronic trials testing the effect of selected plant-based foods on vascular function parameters in older subjects, and consider plausible mechanisms that may support the main findings. A total of 15 trials were included and analyzed, testing the effects of beetroot, plum, blueberry, and vegetable oils. We found some interesting results regarding markers of vascular reactivity, in particular for beetroot, while no effects were found for markers of arterial stiffness. The amelioration of vascular function seems to be more related to the restoration of a condition of nitric oxide impairment, exacerbated by diseases or hypoxic condition, rather than the enhancement of a physiological situation, as indicated by the limited effects on healthy older subjects or in control groups with young subjects. However, the overall set of selected studies is, in any case, rather limited and heterogeneous in terms of characteristics of the studies, indicating the need for additional high-quality intervention trials to better clarify the role of vegetable foods in restoring and/or improving vascular function in order to better elucidate the mechanisms through which these foods may exert their vascular health benefits in older subjects.  相似文献   
89.
90.
The Mediterranean Diet (MD) is a healthy dietary pattern, demonstrated to reduce the risk of cancer, diabetes, cardiovascular and neurodegenerative diseases, and early death. The Mediterranean Adequacy Index (MAI) is used to measure adherence to the MD in perspective studies in the general population and correlates with cardiovascular events. The aim of this study was to calculate the MAI among patients with advanced chronic kidney disease (CKD) and correlate it with traditional uremic, microbiota-derived, and proatherogenic toxins as well as nutritional status, quality of life, and cardiovascular events. A total of 60 adult patients with advanced CKD were enrolled and their MAI was calculated. According to the median value, patients were divided into lower (l-MAI, <1.80) and higher (h-MAI, ≥1.80) MAI groups. Biochemical parameters, microbiota-derived and proatherogenic toxins (p-Cresyl sulphate, Indoxyl-sulphate, and Lipoprotein-associated phospholipase A2), nutritional status, quality of life, and cardiovascular events that occurred in the previous three years were recorded. The mean value of the MAI was 2.78 ± 2.86. The MAI was significantly higher in foreigners (median (IQR) 6.38 (8.98) vs. 1.74 (1.67), p < 0.001) and diabetic patients. The l-MAI and h-MAI groups had similar routinary blood, p-Cresyl-sulphate, Indoxyl-sulphate, and Lp-PLA2 as well as nutritional status and quality of life parameters. The MAI was not associated with previous cardiovascular events and did not correlate with cardiovascular events in CKD patients. New and nephro-tailored indexes are warranted to evaluate nutritional therapy in CKD patients.  相似文献   
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