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111.
Ultra-small palladium nanoparticles were synthesized and applied as catalysts for a hydrogen evolution reaction. The palladium metal precursor was produced via beta-cyclodextrin as organo-nanocup (ONC) capping agent to produce ultra-small nanoparticles used in this study. The produced ~3 nm nanoparticle catalyst was then characterized via X-ray diffraction (XRD), transmission electron microscopy (TEM), ultraviolet-visible spectroscopy (UV-Vis), and Fourier transform infrared spectroscopy (FTIR) to confirm the successful synthesis of ~3 nm palladium nanoparticles. The nanoparticles’ catalytic ability was explored via the hydrolysis reaction of sodium borohydride. The palladium nanoparticle catalyst performed best at 303 K at a pH of 7 with 925 μmol of sodium borohydride having an H2 generation rate of 1.431 mL min−1 mLcat−1. The activation energy of the palladium catalyst was calculated to be 58.9 kJ/mol. 相似文献
112.
Worsening heart failure in ‘real‐world’ clinical practice: predictors and prognostic impact
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113.
Outcome of transcatheter aortic valve implantation in high risk patients with severe aortic stenosis
Hamdy Soliman Khlid Alrabaat Tarek Aboalaazm Shaimaa Mostafa Asaad Samy 《The Egyptian Heart Journal》2017,69(4):261-271
Aim
To assess outcome of TAVI in high risk patients with severe symptomatic aortic stenosis.Patients and methods
40 patients with symptomatic severe aortic stenosis and high risk underwent TAVI with implantation of either Sapien XT valve or Core Valve and followed for 6 months. Device success, cardiovascular mortality, myocardial infarction, stroke, life-threatening bleeding and vascular complications were defined according to Valve Academic Research Consortium definitions.Results
The study included 40 patients, their mean age was 73.98 ± 8.40, procedural success was 97.5%. One patient need valve in valve due to moderately severe paravalvular leak. Total mortality was 7.5%, cardiovascular death occurred in 2.5% and non cardiovascular death occurred in 5%. Myocardial infarction occurred in one patient (2.5%), stroke occurred in 2 patients (5%), minor bleeding occurred in 6 patients (15%), major bleeding occurred in 3 patients (7.5%), minor vascular complications occurred in 4 patients (10%) while major vascular complications occurred in 3 patients (7.5%). Permanent pacemaker was inserted for 5 patients (12.5%), new onset AF occurred in 4 patients (10%). Re hospitalization was needed for 2 patients (5%) due to heart failure. After TAVI there were significant improvement in NYHA functional class (p < 0.001), mean LV ejection fraction and LV mass index (p < 0.001), mean aortic valve area, mean and peak pressure gradient (p < 0.001), severity of aortic and mitral regurgitation (p < 0.001). When comparing types of valves used, both were nearly comparable.Conclusion
TAVI is a safe and effective procedure in selected high-risk patients with severe symptomatic aortic stenosis without significant difference between used valves. 相似文献114.
Gabriela Marsavela Ashleigh C. McEvoy Michelle R. Pereira Anna L. Reid Zeyad Al-Ogaili Lydia Warburton Muhammad A. Khattak Afaf Abed Tarek M. Meniawy Michael Millward Melanie R. Ziman Leslie Calapre Elin S. Gray 《British journal of cancer》2022,126(3):401
Background The validity of circulating tumour DNA (ctDNA) as an indicator of disease progression compared to medical imaging in patients with metastatic melanoma requires detailed evaluation.Methods Here, we carried out a retrospective ctDNA analysis of 108 plasma samples collected at the time of disease progression. We also analysed a validation cohort of 66 metastatic melanoma patients monitored prospectively after response to systemic therapy.Results ctDNA was detected in 62% of patients at the time of disease progression. For 67 patients that responded to treatment, the mean ctDNA level at progressive disease was significantly higher than at the time of response (P < 0.0001). However, only 30 of these 67 (45%) patients had a statistically significant increase in ctDNA by Poisson test. A validation cohort of 66 metastatic melanoma patients monitored prospectively indicated a 56% detection rate of ctDNA at progression, with only two cases showing increased ctDNA prior to radiological progression. Finally, a correlation between ctDNA levels and metabolic tumour burden was only observed in treatment naïve patients but not at the time of progression in a subgroup of patients failing BRAF inhibition (N = 15).Conclusions These results highlight the low efficacy of ctDNA to detect disease progression in melanoma when compared mainly to standard positron emission tomography imaging.Subject terms: Tumour biomarkers, Biomarkers 相似文献
115.
Yassamine Ouerdane Mohamed Sayed Zaazouee Moaiad Eldin Ahmed Mohamed Mohammed Tarek Hasan Mohamed Hamdy Abdallah Magdy Ghoneim Mohamed Ibrahim Gbreel Ahmed Mohamed Ibrahim Khaled Mohamed Ragab Anas Zakarya Nourelden 《Indian journal of ophthalmology》2021,69(12):3421
Photorefractive keratectomy (PRK) is considered a safe approach laser procedure with a clinical significance in correcting myopia results. PRK requires removing the whole superficial epithelium. The integrity of the epithelial basement membrane and the deposition of abnormal extracellular matrix can put the cornea in a probable situation for corneal haze formation. Mitomycin C (MMC) is applied after excimer laser ablation as a primary modulator for wound healing, limiting corneal haze formation. We aim to summarize the outcomes of MMC application after laser ablation. We searched Scopus, PubMed, Cochrane CENTRAL, and Web of Science till December 2020 using relevant keywords. The data were extracted and pooled as mean difference (MD) or risk ratio (RR) with a 95% confidence interval (CI), using Review Manager software (version 5.4). Our analysis demonstrated a statistically significant result for MMC application over the control group in terms of corneal haze formation postoperatively (RR = 0.29, 95% CI: [0.19, 0.45], P < 0.00001). Regarding corrected distance visual acuity (CDVA), no significant difference was observed between the MMC group and the control group (MD = 0.02; 95% CI: [-0.04, 0.07]; P = 0.56). Regarding the uncorrected distance visual acuity (UDVA), the analysis favored the MMC application with (MD -0.03, 95% CI: [-0.06, -0.00]; P = 0.05). There was no statistically significant increase in complications with MMC. In conclusion, MMC application after PRK is associated with a lower incidence of corneal haze formation with no statistically significant side effects. The long term effect can show improvement regarding UDVA favoring MMC. However, there is no significant effect of MMCs application regarding CDVA, and SE. 相似文献
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Objective To evaluate the rate and characteristics of postoperative intrauterine adhesions (IUA) that might be formed following hysteroscopic
reproductive surgery from both a gross and a histologic perspective as determined by early and late follow-up diagnostic hysteroscopy.
Methods Retrospective analysis of 61 women wishing a pregnancy and suffering from a significant intrauterine pathology affecting their
reproductive outcome were reviewed. All patients were treated hysteroscopically. Subsequently, they were randomly assigned
to perform a follow-up diagnostic hysteroscopy at a variable intervals from their initial surgery. Multiple hysteroscopic-guided
biopsies from IUA, when present, were obtained in several cases. Twenty patients were in the early group and had follow-up
hysteroscopy performed 2–4 weeks after the initial operation. The late diagnostic group consisted of 41 patients with follow-up
hysteroscopy at about 12 months (8–16 months). The two groups were similar to composition. Postoperatively, none of the early
diagnostic group underwent hysterosalpingography (HSG) whereas all of the late group performed HSG 4 months following the
initial surgery, which showed at least one-third of the cavity free of adhesions. When adhesions were present, no effort was
made to lyse them.
Results At follow-up hysteroscopy, 25% of both groups had no significant adhesions. Grade I adhesions (thin, filmy) occurred in 60%
of the early hysteroscopy patients and in only 12% of the late group (P < 0.05). Grade II adhesions were present in 10% of the early group and in up to 41% in the late group (P < 0.05), whereas Grade III adhesions were present in only 5% of the early hysteroscopy group, but in 22% of the late one
(P < 0.05). Correlation between hysteroscopic and histologic findings were good in most of cases in both groups. Follow-up to
determine the subsequent reproductive outcome revealed similar conception rates in both groups.
Conclusion The IUA that might be formed immediately following hysteroscopic reproductive surgery are histologically different from those
appearing a longer time after the original operation. Routine early follow-up hysteroscopy can influence the prognosis resulting
from the original surgery. 相似文献
120.
El-Toukhy T Sunkara SK Coomarasamy A Grace J Khalaf Y 《Reproductive biomedicine online》2008,16(5):712-719
A systematic review of studies evaluating the influence of outpatient (office) hysteroscopy on the outcome of the subsequent IVF cycle was conducted. MEDLINE, EMBASE, the Cochrane Library, National Research Register, ISI Conference Proceedings, ISRCTN Register and Meta-register were searched for randomized controlled trials (up to July 2007). All trials comparing the outcome of IVF treatment performed in patients who had outpatient hysteroscopy in the cycle preceding their IVF treatment with a control group in which hysteroscopy was not performed were included. Study selection, quality appraisal and data extraction were performed independently and in duplicate. Study authors were contacted for additional information. The main outcome measure was pregnancy rate. In total, 1691 participants were included in two randomized (n = 941) and three non-randomized controlled studies (n = 750). The quality of the studies was variable. Meta-analyses of the results of five studies showed evidence of benefit from outpatient hysteroscopy in improving the pregnancy rate in the subsequent IVF cycle (pooled relative risk = 1.75, 95% CI 1.51-2.03). The evidence from randomized trials was consistent with that from non-randomized controlled studies. Future robust randomized trials comparing outpatient hysteroscopy or mini-hysteroscopy with no intervention before IVF treatment would be a useful addition to further guide clinical practice. 相似文献