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排序方式: 共有3128条查询结果,搜索用时 15 毫秒
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Gabriella O. Lopes Paulo Farinatti Karynne G. Lopes Daniel J. Medeiros‐Lima Cristiane Matsuura Ricardo B. Oliveira Eliete Bouskela Daniel A. Bottino Fabiana Muccillo Eduardo Tibirica Juliana P. Borges 《Scandinavian journal of medicine & science in sports》2019,29(1):25-33
This study compared macro‐ and microvascular endothelial function and redox status in active vs inactive HIV‐infected patients (HIVP) under antiretroviral therapy. Using a cross‐sectional design, macro‐ and microvascular reactivity, systemic microvascular density, and oxidative stress were compared between 19 HIVP (53.1 ± 6.1 year) enrolled in a multimodal training program (aerobic, strength and flexibility exercises) for at least 12 months (60‐minutes sessions performed 3 times/wk with moderate intensity) vs 25 sedentary HIVP (51.2 ± 6.3 year). Forearm blood flow during reactive hyperemia (521.7 ± 241.9 vs 361.4% ± 125.0%; P = 0.04) and systemic microvascular density (120.8 ± 21.1 vs 105.6 ± 25.0 capillaries/mm2; P = 0.03) was greater in active than inactive patients. No significant difference between groups was detected for endothelium‐dependent and independent skin microvascular vasodilation (P > 0.05). As for redox status, carbonyl groups (P = 0.22), lipid peroxidation (P = 0.86), catalase activity (P = 0.99), and nitric oxide levels (P = 0.72) were similar across groups. However, superoxide dismutase activity was greater in active vs inactive HIVP (0.118 ± 0.013 vs 0.111 ± 0.007 U/mL; P = 0.05). Immune function reflected by total T CD4 and T CD8 counts (cell/mm3) did not differ between active and inactive groups (P > 0.82). In conclusion, physically active HIVP exhibited similar immune function, but greater macrovascular reactivity, systemic microvascular density, and superoxide dismutase activity than inactive patients of similar age. 相似文献
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Carlos Eduardo Bezerra Moura Naisandra Bezerra Silva Juliana Carvalho Sa Geraldo Barroso Cavalcanti Junior Silvia Regina Batistuzzo de Medeiros Hugo Alexandre Oliveira Rocha Paula Carvalho Papa Clodomiro Alves Jr 《Artificial organs》2016,40(5):497-504
To evaluate the effect of topography in nanoscale, titanium surfaces were bombarded by argon ions (a chemically inert gas), in an atmosphere of plasma. The effects of surface parameters on morphology, adhesion, proliferation, and MC3T3‐E1 preosteoblasts differentiation were analyzed. Nontreated (smooth) surfaces were used as a control. The levels of average roughness (Ra) observed in bombarded and smooth titanium surfaces were of 95 and 14 nm, respectively. The wettability increased on treated surfaces. The number of attached cells (30 and 60 min) was significantly higher on the bombarded surface. The cell proliferation after 3 and 7 days was also significantly higher on the ion‐bombarded surface. In addition, the ALP activity and expression of osteocalcin were higher in cells grown on the treated surface. The results showed that bombardment with argon ions increased the roughness and the wettability of the Ti surface, promoting a significant increase in the adhesion, proliferation, and differentiation of preosteoblasts. 相似文献
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Vianna CB Gonzalez MM Dallan LA Shiozaki AA Medeiros FM Britto PC Cesar LA 《Resuscitation》2007,74(1):183-186
A previously asymptomatic 15-year-old boy was treated at our institution after an episode of chest pain, palpitation, and syncope while playing in a high school soccer game. The patient's resting electrocardiogram was normal. A transthoracic echocardiogram showed an anomalous left main coronary artery originating from the right sinus of Valsalva. Contrast-enhanced multidetector computed tomography demonstrated clearly that the anomalous vessel coursed between the aorta and the pulmonary trunk (interarterial subtype). Treadmill testing registered several nonsustained polymorphic ventricular tachycardias and transmural myocardial ischaemia in the early recovery phase (ST-elevation up to 5mm in CM5 and V2 leads). The patient underwent bypass grafting. One year later, he remains asymptomatic, and new treadmill tests have been normal. In this patient, severe transmural myocardial ischaemia was detected, possibly due to collapse or vasospasm of the anomalous vessel, triggering life-threatening ventricular arrhythmias. 相似文献
98.
Alvares I Sensi LG Araujo EM Araujo E 《Journal of esthetic and restorative dentistry : official publication of the American Academy of Esthetic Dentistry ... [et al.]》2007,19(5):240-245
Tooth fragment reattachment is a simple, conservative, fast, and affordable treatment option for fractured teeth when the fragment is available. However, this technique can present some difficulties, among which is the possibility of the fragment being positioned and bonded inadequately. To avoid this situation, it is necessary to establish a reference for the adequate positioning of the fragment using a silicone index. CLINICAL SIGNIFICANCE: This article presents an alternative approach for better handling of tooth fragments resulting from trauma by using a silicone index as a guide to proper positioning and bonding. 相似文献
99.
This study analyzed the depth of cure of a composite assessed by microhardness and the degree of conversion as a function of the light cure unit (LCU) used. Two light cure units, one LED (Ultraled-Dabi Atlante) and one quartz-tungsten-halogen (QTH, Optilux 401-Demetron) unit were used to cure 4.0 x 4.0 mm and 5.0 mm deep composite specimens (Filtek Z250, 3M ESPE). After 24 hours storage at 37 degrees C, Knoop microhardness and degree of conversion were measured on the irradiated surface and at each millimeter of the sample's depth. The degree of conversion was determined by using micro-Raman spectroscopy. The specimens cured with the QTH unit presented uniform decay in microhardness up to 4 mm in depth. Beyond 4 mm, the drop was abrupt. With LED photoactivation, uniform decay was observed only up to 2 mm. At higher depths, the decay in microhardness increased rapidly, especially beyond 3 mm. Depth of cure assessed by micro-Raman revealed that the degree of conversion behaved similarly to microhardness for both LCUs. A strong linear regression between microhardness and the degree of conversion, including both LCUs, was established with R2 = 0.980. 相似文献