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排序方式: 共有2577条查询结果,搜索用时 15 毫秒
71.
Steeve Doizi Thomas Knoll Cesare M. Scoffone Alberto Breda Marianne Brehmer Evangelos Liatsikos Jean-Nicolas Cornu Olivier Traxer 《World journal of urology》2014,32(1):143-147
Purpose
The use of a ureteral access sheath (UAS) during flexible retrograde intrarenal surgery (RIRS) has become increasingly popular. Our aim was to evaluate the accessibility of a new UAS device, allowing the transformation of the working guidewire into a safety guidewire.Methods
A prospective, multicenter study was conducted between January and February 2010 in six European tertiary reference centers. Patients needing flexible RIRS were eligible to participate in the study. In all cases, insertion of the Re-Trace? (12/14Fr, Coloplast, Denmark) was attempted at the beginning of the procedure. Insertion success was defined as placement of the UAS in the lumbar ureter with successful disengagement of the working guidewire, which turned into a safety guidewire. Influence of gender and pre-stenting status was analyzed by univariate analysis.Results
137 UASs were used in 75 male and 62 female patients. 25.5 % of ureters were pre-stented: men were 2.17 more often pre-stented than women. The overall Re-Trace? insertion rate was 82.5 %. Success rate was not significantly different between men and women (77.3 vs. 88.7 %, respectively, p = 0.11). Pre-stenting status did not significantly influence the success rate (p = 0.31). When analyzing the combined influence of pre-stenting status and gender, the worst success rates seemed to be obtained in men without pre-stenting, but no significant differences were found between groups.Conclusions
Re-Trace? UAS showed good overall insertion rates. This evaluation validated the new concept of guidewire disengagement: A single wire automatically switches from working to safety role. 相似文献72.
Neuronal patterning on microfabricated architectures has developed rapidly over the past few years, together with the emergence of soft biocompatible materials and tissue engineering scaffolds. Previously, we introduced a patterning technique based on serum and the biopolymer parylene-C, achieving highly compliant growth of primary neurons and astrocytes on different geometries. Here, we expanded this technique and illustrated that neuralized cells derived from mouse embryonic stem cells (mESCs) followed stripes of variable widths with conformity equal to or higher than that of primary neurons and astrocytes. Our results indicate the presence of undifferentiated mESCs, which also conformed to the underlying patterns to a high degree. This is an exciting and unexpected outcome, as molecular mechanisms governing cell and ECM protein interactions are different in stem cells and primary cells. Our study enables further investigations into the development and electrophysiology of differentiating patterned neural stem cells. 相似文献
73.
Nikolaos Orologas-Stavrou Marianna Politou Pantelis Rousakis Ioannis V. Kostopoulos Ioannis Ntanasis-Stathopoulos Edison Jahaj Eleni Tsiligkeridou Maria Gavriatopoulou Efstathios Kastritis Anastasia Kotanidou Meletios-Athanasios Dimopoulos Ourania E. Tsitsilonis Evangelos Terpos 《Viruses》2021,13(1)
Immune profiling of patients with COVID-19 has shown that SARS-CoV-2 causes severe lymphocyte deficiencies (e.g., lymphopenia, decreased numbers, and exhaustion of T cells) and increased levels of pro-inflammatory monocytes. Peripheral blood (PB) samples from convalescent plasma (CP) donors, COVID-19 patients, and control subjects were analyzed by multiparametric flow cytometry, allowing the identification of a wide panel of immune cells, comprising lymphocytes (T, B, natural killer (NK) and NKT cells), monocytes, granulocytes, and their subsets. Compared to active COVID-19 patients, our results revealed that the immune profile of recovered donors was restored for most subpopulations. Nevertheless, even 2 months after recovery, CP donors still had reduced levels of CD4+ T and B cells, as well as granulocytes. CP donors with non-detectable levels of anti-SARS-CoV-2-specific antibodies in their serum were characterized by higher Th9 and Th17 cells, which were possibly expanded at the expense of Th2 humoral immunity. The most noticeable alterations were identified in previously hospitalized CP donors, who presented the lowest levels of CD8+ regulatory T cells, the highest levels of CD56+CD16− NKT cells, and a promotion of a Th17-type phenotype, which might be associated with a prolonged pro-inflammatory response. A longer follow-up of CP donors will eventually reveal the time needed for full recovery of their immune system competence. 相似文献
74.
Emmanouil-George C. Tzanakakis Evangelos Skoulas Eudoxie Pepelassi Petros Koidis Ioannis G. Tzoutzas 《Materials》2021,14(12)
Lasers have been well integrated in clinical dentistry for the last two decades, providing clinical alternatives in the management of both soft and hard tissues with an expanding use in the field of dental materials. One of their main advantages is that they can deliver very low to very high concentrated power at an exact point on any substrate by all possible means. The aim of this review is to thoroughly analyze the use of lasers in the processing of dental materials and to enlighten the new trends in laser technology focused on dental material management. New approaches for the elaboration of dental materials that require high energy levels and delicate processing, such as metals, ceramics, and resins are provided, while time consuming laboratory procedures, such as cutting restorative materials, welding, and sintering are facilitated. In addition, surface characteristics of titanium alloys and high strength ceramics can be altered. Finally, the potential of lasers to increase the adhesion of zirconia ceramics to different substrates has been tested for all laser devices, including a new ultrafast generation of lasers. 相似文献
75.
76.
Anita B. Amorim Milena Simic Evangelos Pappas Joshua R. Zadro Eduvigis Carrillo Juan R. Ordoñana Paulo H. Ferreira 《Revista brasileira de fisioterapia (S?o Carlos (S?o Paulo, Brazil))》2019,23(3):257-265
BackgroundLow back pain is a highly prevalent and disabling musculoskeletal disorder. Physical activity is widely used as a prevention strategy for numerous musculoskeletal disorders; however, there is still conflicting evidence as to whether physical activity is a protective or risk factor for low back pain or whether activity levels differ between people with and without low back pain.ObjectiveTo investigate the association between low back pain and different types (occupational and leisure) and intensities (moderate and vigorous) of physical activity.MethodsThis is cross-sectional observational study. We included in this study a total of 1059 individuals recruited from a Spanish twin registry with data available on low back pain. Outcome: Self-reported leisure and occupational physical activity were the explanatory variables. The low back pain outcome used in this study was recurrent low back pain.ResultsOur results indicate that leisure physical activity is associated with a lower prevalence of recurrent low back pain. In contrast, occupational physical activity, such as carrying, lifting heavy weight while inclined, awkward postures (e.g. bending, twisting, squatting, and kneeling) are associated with a higher prevalence of recurrent low back pain. There was no statistically significant association between other occupational physical activities, such as sitting or standing, and low back pain.ConclusionLeisure and occupational physical activity are likely to have an opposed impact on low back pain. While leisure physical activity appears to be protective, occupational physical activity appears to be harmful to low back pain. Future longitudinal studies should assist in formulating guidelines addressing specific types and intensity of physical activity aimed at effectively preventing low back pain. 相似文献
77.
The role of the NO axis and its therapeutic implications in pulmonary arterial hypertension 总被引:3,自引:0,他引:3
Michelakis ED 《Heart failure reviews》2003,8(1):5-21
78.
Plasma Levels of Nitrites/Nitrates in Patients with Chronic Atrial Fibrillation are Increased after Electrical Restoration of Sinus Rhythm 总被引:5,自引:0,他引:5
Dragana Nikitovic Evangelos A. Zacharis Emmanuel G. Manios Nikki E. Malliaraki Emmanuel M. Kanoupakis Katerina I. Sfiridaki Emmanuel I. Skalidis Andreas N. Margioris Panos E. Vardas 《Journal of interventional cardiac electrophysiology》2002,7(2):171-176
Introduction: Patients with persistent atrial fibrillation (AF) have hemodynamic changes, which impair endothelial cell function resulting in decreased nitric oxide (NO) production. The aim of this work was to assess endothelial function in AF patients before and at various time points after cardioversion.
Methods: Forty-two patients with AF and 21 normal and age-adjusted healthy controls were studied. Nitrites and nitrates (NO
x
) and von Willebrand factor (vWf) concentrations were measured on blood samples taken just before cardioversion and over a 30 day period after the procedure.
Results: Plasma levels of NO
x
in AF were significantly lower compared to healthy controls (p < 0.001), but after cardioversion gradually increased to approach to those of the healthy controls by the end of the first month of sustained sinus rhythm (p = 0.004). Interestingly plasma levels of NO
x
were negatively correlated to left atrial volume measured by ultrasonography (r = –0.34, p < 0.05). Plasma levels of vWf in AF patients were significantly higher compared to the healthy controls (p < 0.01) but with sustained sinus rhythm decreased (p = 0.02).
Conclusion: The parallel normalization of the NO
x
titers and vWf levels suggests that vascular endothelial function improves after 30 days of normal sinus rhythm. 相似文献
79.