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排序方式: 共有7397条查询结果,搜索用时 15 毫秒
61.
Rhanderson Cardoso Gustavo B. Justino Fabrissio P. Graffunder Leticia Benevides Leonardo Knijnik Luana M.F. Sanchez Andre dAvila 《Arquivos brasileiros de cardiologia》2022,119(1):87
BackgroundCatheter ablation is a well-established therapy for rhythm control in patients who are refractory or intolerant to anti-arrhythmic drugs (AAD). Less is known about the efficacy of catheter ablation compared with AAD as a first-line strategy for rhythm control in atrial fibrillation (AF).ObjectivesWe aimed to perform a systematic review and meta-analysis of catheter ablation vs. AAD in patients naïve to prior rhythm control therapies.MethodsPubMed, EMBASE, and Cochrane databases were searched for randomized controlled trials that compared catheter ablation to AAD for initial rhythm control in symptomatic AF and reported the outcomes of (1) recurrent atrial tachyarrhythmias (ATs); (2) symptomatic AF; (3) hospitalizations; and (4) symptomatic bradycardia. Heterogeneity was examined with I2statistics. P values of < 0.05 were considered statistically significant.ResultsWe included five trials with 994 patients, of whom 502 (50.5%) underwent catheter ablation. Mean follow-up ranged from one to five years. Recurrences of AT (OR 0.36; 95% CI 0.25-0.52; p<0.001) and symptomatic AF (OR 0.32; 95% CI 0.18-0.57; p<0.001), and hospitalizations (OR 0.25; 95% CI 0.15-0.42; p<0.001) were significantly less frequent in patients treated with catheter ablation compared with AAD. Symptomatic bradycardia was not significantly different between groups (OR 0.55; 95% CI 0.18-1.65; p=0.28). Significant pericardial effusions or tamponade occurred in eight of 464 (1.7%) patients in the catheter ablation group.ConclusionThese findings suggest that catheter ablation has superior efficacy to AAD as an initial rhythm control strategy in patients with symptomatic AF. 相似文献
62.
Portela JG Costa AC Teixeira LS 《Journal of pharmaceutical and biomedical analysis》2004,34(3):543-549
In this work, a new solid phase spectrophotometric method in association with flow injection analysis for Vitamin B6 (pyridoxine) determination has been developed with direct measurement of light-absorption in C18 material. In the developed method, successive passage of the complex, previously formed in the flowing stream, and eluent through the flow cell and continuous monitoring of the process provided the analytical information needed to determine pyridoxine. Pharmaceutical samples containing Vitamin B6 were previously dissolved in 0.1 mol l(-1) phosphate buffer solution (pH 7.5) and a sample volume of 235 microl was injected directly into carrier stream consisting of a mixture of methanol and 0.1 mol l(-1) phosphate buffer solution adjusted to pH 7.0 (1+1, v/v). The blue indophenol dye produced from the reaction between pyridoxine and N,N-diethyl-p-phenylenediamine after oxidation by potassium hexacyanoferrate(III) was quantitatively retained on C18 support and the spectrophotometric detection was performed simultaneously at 633 nm. The retained complex was quickly eluted from C18 material with the eluent stream consisting of a mixture of methanol and 0.01 mol l(-1) HCl (6+4, v/v). The results showed that the proposed method is simple, rapid and the analytical response is linear in the concentration range of 0.5-10 and 0.2-4 mg l(-1) using 235 and 860 microl of sample, respectively. The limits of detection are 0.15 and 0.060 mg l(-1) and the R.S.D. are 3.6% (at 2 mg l(-1) level) and 4.0% (at 1 mg l(-1) level) using sample volume of 235 and 860 microl, respectively. The system presented an analytical throughput of 15 determinations per hour when a sample volume of 235 microl was utilized. The procedure was successfully applied to the determination of Vitamin B6 in pharmaceutical formulations containing vitamins of B group and others active principles such as Vitamin C and minerals. 相似文献
63.
64.
AIM: To assess the efficacy and safety of patterned laser trabeculoplasty (PLT) as an adjunctive treatment in open-angle glaucoma (OAG) or ocular hypertension (OHT) patients who were under antiglaucoma medical treatment.
METHODS: This study was a retrospective review of primary or secondary OAG patients and OHT patients with medically uncontrolled (≥18 mm Hg) intraocular pressure (IOP) who underwent 360º PLT from June 2016 to August 2016. Follow-up visits at week 1, and 1, 3 and 6mo were performed. IOP, best corrected visual acuity (BCVA), complications and eye drop glaucoma medication were recorded at each follow-up visit. Success was defined as IOP reduction ≥20% from baseline.
RESULTS: Forty one eyes of 25 patients were included in this study. Pre-treatment mean IOP was 20.2±1.6 mm Hg. After PLT, IOP was 19.3±5.2, 16.1±2.7, 17.1±3.7 and 16.3±3.5 mm Hg, at 1wk, 1, 3 and 6mo, respectively. IOP reduction from baseline was statistically significant from the first month, remaining stable at 6mo (P<0.001). PLT success at 6mo of follow-up was 48.7%. The number of glaucoma medication per eye (P=0.10) and the mean BCVA both remained constant (P=0.37). Complications included transient IOP spikes in 4 eyes (9.7%) and peripheral anterior synechiae in 7 eyes (17.1%).
CONCLUSION: PLT is an effective and safe method for the management of patients with OHT or OAG as an adjunctive therapy. Additional larger studies should be designed to verify the long-term stability of IOP reduction with this laser technology. 相似文献
65.
Kan Yonemori Yasutoshi Kuboki Kosei Hasegawa Takashi Iwata Hidenori Kato Kazuhiro Takehara Yasuyuki Hirashima Hisamori Kato Chaitali Passey Jeppe Klint Buchbjerg Jeffrey R. Harris Camilla
Mondrup Andreassen Leonardo Nicacio Ibrahima Soumaoro Keiichi Fujiwara 《Cancer science》2022,113(8):2788
New treatments, particularly second‐line options, are needed to improve outcomes for patients with recurrent/metastatic cervical cancer (r/mCC). Tisotumab vedotin (TV) is an antibody–drug conjugate directed to tissue factor, a transmembrane protein commonly expressed in cancer cells, to deliver cytotoxic monomethyl auristatin E. This single‐arm, open‐label phase 1/2 trial evaluated the consistency of safety and efficacy outcomes of TV in Japanese patients with r/mCC to bridge the current findings with those reported in previous trials in non‐Japanese patients in the United States and Europe. In part 1 (dose escalation; N = 6), patients with advanced solid tumors received TV 1.5 or 2.0 mg/kg once every 3 weeks to determine the maximum tolerated dose (MTD) and recommended phase 2 dose (RP2D). Part 2 (dose expansion; N = 17) evaluated the RP2D in r/mCC patients with 1–2 prior lines of therapy. In part 1, no dose‐limiting toxicities were observed, the MTD was not reached, and TV 2.0 mg/kg was established as the RP2D. In part 2, the most common treatment‐emergent adverse events were anemia (58.8%), nausea (58.8%), alopecia (47.1%), epistaxis (47.1%), and diarrhea (35.3%); adverse events of special interest were bleeding (76.5%), ocular events (35.3%), and peripheral neuropathy (17.6%), and were mostly grade 1/2. In part 2, confirmed objective response rate was 29.4%, median duration of response was 7.1 months, and median time to response was 1.2 months. In Japanese patients with r/mCC, TV demonstrated a manageable and tolerable safety, pharmacokinetics, and efficacy profile consistent with that observed in non‐Japanese patients. 相似文献
66.
Mateus J Pereira L Baxter J Berghella V Tolosa J 《American journal of perinatology》2007,24(6):381-385
The purpose of this study is to determine the effectiveness of fetal fibronectin (FFN) compared to assessment of cervical dilation (CD) in clinical management of women with symptomatic preterm labor (PTL). Pregnant women presenting to Thomas Jefferson University Hospital between May 1, 2001 and November 30, 2002 with symptomatic PTL underwent FFN sampling and had a complete clinical evaluation including a pelvic bimanual examination. Inclusion criteria were singleton pregnancy, gestational age (GA) between 24 (0) and 33 (6) weeks, CD < 3 cm, and intact amniotic membranes. FFN samples were sent out and results were available within 4-12 hours. Clinical management including tocolysis, antenatal steroids, and hospitalization was determined based on digital CD assessment and FFN status. A dilated cervix was defined as CD > 1 cm. Ninety-three patients were included. Spontaneous preterm delivery (SPTD) at < 37 weeks occurred in 20 of 93 (21.5%) patients. Medical therapy use was significantly higher in patients with dilated cervix than in those with a closed cervix (all P values < 0.05). Tocolysis and steroid use in FFN-negative patients and FFN-positive patients were not significantly different. Furthermore, tocolytic use was higher in FFN-negative patients than in women with positive FFN (50% versus 42.1%; P = 0.53). Use of antenatal steroids was similar in patients with CD >/= 1 cm and a positive FFN (54.5% versus 47.4%; P = 0.92). Compared with FFN-negative patients, women with closed cervix were less likely to undergo interventions. In symptomatic PTL patients, CD determined clinical management more than FFN status. Overall, the use of FFN was not effective in decreasing "unnecessary" clinical interventions. 相似文献
67.
Valentina Hernndez Davor Ibarra Johan F. Triana Bastian Martínez-Soto Matías Faúndez Diego A. Vasco Leonardo Gordillo Felipe Herrera Claudio García-Herrera Alysia Garmulewicz 《Materials》2022,15(11)
This article focuses on agar biopolymer films that offer promise for developing biodegradable packaging, an important solution for reducing plastics pollution. At present there is a lack of data on the mechanical performance of agar biopolymer films using a simple plasticizer. This study takes a Design of Experiments approach to analyze how agar-glycerin biopolymer films perform across a range of ingredients concentrations in terms of their strength, elasticity, and ductility. Our results demonstrate that by systematically varying the quantity of agar and glycerin, tensile properties can be achieved that are comparable to agar-based materials with more complex formulations. Not only does our study significantly broaden the amount of data available on the range of mechanical performance that can be achieved with simple agar biopolymer films, but the data can also be used to guide further optimization efforts that start with a basic formulation that performs well on certain property dimensions. We also find that select formulations have similar tensile properties to thermoplastic starch (TPS), acrylonitrile butadiene styrene (ABS), and polypropylene (PP), indicating potential suitability for select packaging applications. We use our experimental dataset to train a neural network regression model that predicts the Young’s modulus, ultimate tensile strength, and elongation at break of agar biopolymer films given their composition. Our findings support the development of further data-driven design and fabrication workflows. 相似文献
68.
Alessio Alfieri Juraj Koudelka Mosi Li Sanny Scheffer Jessica Duncombe Andrea Caporali Rajesh N Kalaria Colin Smith Ajay M Shah Karen Horsburgh 《Journal of cerebral blood flow and metabolism》2022,42(7):1176
Chronic microvascular inflammation and oxidative stress are inter-related mechanisms underpinning white matter disease and vascular cognitive impairment (VCI). A proposed mediator is nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 2 (Nox2), a major source of reactive oxygen species (ROS) in the brain. To assess the role of Nox2 in VCI, we studied a tractable model with white matter pathology and cognitive impairment induced by bilateral carotid artery stenosis (BCAS). Mice with genetic deletion of Nox2 (Nox2 KO) were compared to wild-type (WT) following BCAS. Sustained BCAS over 12 weeks in WT mice induced Nox2 expression, indices of microvascular inflammation and oxidative damage, along with white matter pathology culminating in a marked cognitive impairment, which were all protected by Nox2 genetic deletion. Neurovascular coupling was impaired in WT mice post-BCAS and restored in Nox2 KO mice. Increased vascular expression of chemoattractant mediators, cell-adhesion molecules and endothelial activation factors in WT mice post-BCAS were ameliorated by Nox2 deficiency. The clinical relevance was confirmed by increased vascular Nox2 and indices of microvascular inflammation in human post-mortem subjects with cerebral vascular disease. Our results support Nox2 activity as a critical determinant of VCI, whose targeting may be of therapeutic benefit in cerebral vascular disease. 相似文献
69.
Leonardo Urbano Davide Dalmazzo Pier Paolo Riviera Orazio Baglieri Ezio Santagata 《Materials》2022,15(11)
This paper presents the results of an experimental investigation which was carried out with the purpose of assessing the performance-related properties of an emulsion-based cold-recycled mixture to be employed as a sustainable solution for the surface finishing of unpaved rural roads. This mixture contained significant quantities of recycled components (reclaimed asphalt and mineral sludge), and its composition was fine-tuned by following an innovative mix design procedure. Properties of these mixtures were studied by means of laboratory tests which considered key parameters, such as flowability, indirect tensile stiffness modulus, indirect tensile strength, moisture susceptibility and resistance to permanent deformation. It was found that, by means of the proposed mix design procedure, optimal dosages of the recycled components can be identified, thereby ensuring the achievement of the desired properties in terms of high workability and adequate stiffness and strength. 相似文献
70.
Leonardo Pace Emanuele Nicolai Angelo Luongo Marco Aiello Onofrio A. Catalano Andrea Soricelli Marco Salvatore 《European journal of radiology》2014