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71.
Atrial fibrillation (AF) is an increasingly common cardiac arrhythmia, currently affecting more than 5 million Americans. Management of patients with AF can be complex, with key strategies including selecting rhythm control versus heart rate control and reducing the patient’s risk of stroke or other systemic embolization. The American Heart Association, American College of Cardiology, and Heart Rhythm Society released 2014 Guideline for the Management of Patients with Atrial Fibrillation, which outlines several new recommendations with important clinical implications. Among these are a new recommendation to use the CHA2DS2-Vasc score for stroke risk assessment, rather than the previously advised CHADS2 score, expansion of anticoagulation options in selected patients, decreased emphasis on the role of aspirin, and an increased emphasis on the role of catheter ablation.  相似文献   
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PurposeTo evaluate the effect of controlled ovarian hyperstimulation length and total gonadotropin (GN) dose on recipient live birth rate (LBR) in fresh donor oocyte cycles.MethodsData was obtained from SART CORS on all fresh donor oocyte GnRH antagonist cycles (n = 1049) between 2014 and 2015 which resulted in a single embryo transferred. Donor and recipient demographic information and cycle characteristics were extracted. Binomial regression was used to estimate LBR with respect to days of stimulation (DOS) and total GN dose. Multivariate analysis was performed to evaluate these relationships after controlling for confounders.ResultsOverall LBR in fresh donor oocyte cycles was 57%. Average stimulation length was 14.3 ± 4.9 days, and total GN dose was 2464 ± 1062 IU. On univariate analysis, neither days of stimulation (p = 0.5) nor total GN dose (p = 0.57) was independently correlated with LBR. However, in prolonged stimulations (> 15 days) with high total GN dose (> 3000 IU), as both the cycle length and total GN dose increased, LBR significantly decreased from 63.81 to 48.15% (p = 0.02) and from 67.61 to 48.15% (p = 0.01), respectively. Multivariate analysis showed no significant effect of either DOS or total GN dose on LBR.ConclusionsLBR is significantly decreased in fresh donor oocyte cycles when cycles are prolonged with high total GN dose. However, after controlling for confounders neither DOS nor total GN dose significantly affects LBR.  相似文献   
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Dermatological conditions in children often present initially to general pediatricians. Senior pediatric trainees in the UK were surveyed regarding their experience and confidence in diagnosis and management with skin conditions, and their satisfaction with postgraduate training. Confidence was reasonable in common conditions but lower for emergencies, reflecting a lack of exposure, and satisfaction with training was low. On the job learning and clinic attendance were felt to be most beneficial, alongside learning from specialist review, however dermatologists were not found to be accessible. Informal learning methods are key within postgraduate education and educators must maximise learning opportunities. Dermatologists can play a vital role by encouraging trainees to learn from feedback following specialist review.  相似文献   
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Association between tumour necrosis alpha inhibitors and weight gain has been reported. We examined weight change in our cohort of inflammatory bowel disease patients treated with infliximab (IFX) for over 12 months, its associations and financial implications. Two‐thirds of patients gained weight during the course of therapy. The mean change in weight after 12 months of IFX therapy was 3.3 (±6.5) kg.  相似文献   
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Investigation of hyperpolarized substrate metabolism has been showing utility in real‐time determination of in‐cell and in vivo enzymatic activities. Intracellular reaction rates may vary during the course of a measurement, even on the very short time scales of visibility on hyperpolarized MR, due to many factors such as the availability of the substrate and co‐factors in the intracellular space. Despite this potential variation, the kinetic analysis of hyperpolarized signals typically assumes that the same rate constant (and in many cases, the same rate) applies throughout the course of the reaction as observed via the build‐up and decay of the hyperpolarized signals. We demonstrate here an acquisition approach that can null the need for such an assumption and enable the detection of instantaneous changes in the rate of the reaction during an ex vivo hyperpolarized investigation, (i.e. in the course of the decay of one hyperpolarized substrate dose administered to a viable tissue sample ex vivo). This approach utilizes hyperpolarized product selective saturating‐excitation pulses. Similar pulses have been previously utilized in vivo for spectroscopic imaging. However, we show here favorable consequences to kinetic rate determinations in the preparations used. We implement this acquisition strategy for studies on perfused tissue slices and develop a theory that explains why this particular approach enables the determination of changes in enzymatic rates that are monitored via the chemical conversions of hyperpolarized substrates. Real‐time changes in intracellular reaction rates are demonstrated in perfused brain, liver, and xenograft breast cancer tissue slices and provide another potential differentiation parameter for tissue characterization.  相似文献   
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