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101.

Purpose

Our aim was compare onset time of sciatic nerve blockade (SNB) performed distal to the subgluteal fold using four different ultrasound (US)-guided approaches in patients undergoing foot or ankle surgery.

Methods

Patients were assigned to one of four groups: SI patients received SNB using short-axis (SA) view of the SN and in-plane (IP) placement of block needle (SA-IP approach); LI patients received SNB using long-axis (LA) view of the SN and IP needle placement (LA-IP approach); SO patients received the block using SA view of the SN and out-of-plane (OP) needle placement (SA-OP approach); LO patients received SNB using LA view of the SN and OP needle placement (LA-OP). Primary outcome included onset time of sensory and motor SNB. Patient satisfaction concerning the postoperative analgesia was noted.

Results

The LI group had significantly faster onset of sensory blockade on the distribution of tibial nerve (16.0 ± 5.6 vs. 23.5 ± 3.6) and common peroneal nerve (12.5 ± 4.3 vs. 19.1 ± 5.4 min) in comparison with the LO group. The LI group had significantly faster onset of motor blockade on the distribution of tibial nerve (21.1 ± 6.2 vs. 26 ± 3.1) and common peroneal nerve (17.7 ± 4.8 vs. 23.7 ± 5.8 min.) in comparison with the LO group. The LI group had the highest rate of patient satisfaction for postoperative analgesia and the LO group had the lowest.

Conclusion

The LA-IP approach resulted in a rapid onset of SNB and was associated with the best satisfaction for postoperative analgesia in comparison with LA-OP, SA-IP, and SA-OP approaches for patients undergoing foot and ankle surgery.  相似文献   
102.
103.
104.

Introduction

Revascularization treatment is rapidly becoming an accepted treatment alternative for the management of endodontic pathology in immature permanent teeth with necrotic dental pulps. However, the success and timing of clinical resolution of symptoms, and radiographic outcomes of interest, such as continued hard tissue deposition within the root, are largely unknown.

Methods

In this prospective cohort study, 20 teeth were treated with a standardized revascularization treatment protocol and monitored for clinical and radiographic changes for 1 year. Standardized radiographs were collected at regular intervals, and radiographic changes were quantified.

Results

All 20 treated teeth survived during the 12-month follow-up period, and all 20 also met the clinical criteria for success at 12 months. As a group, the treated teeth showed a statistically significant increase in radiographic root width and length and a decrease in apical diameter, although the changes in many cases were quite small (such that the clinical significance is unclear). The within-case percent change in apical diameter after 3 months was 16% and had increased to 79% by 12 months, with 55% (11/20) showing complete apical closure. The within-case percent change in root length averaged less than 1% at 3 months and increased to 5% at 12 months. The within-case percent change in root thickness averaged 3% at 3 months and 21% at 12 months.

Conclusions

Although clinical success was highly predictable with this procedure, clinically meaningful radiographic root thickening and lengthening are less predictable after 1-year of follow-up. Apical closure is the most consistent radiographic finding.  相似文献   
105.
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   
106.
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   
107.
108.
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   
109.

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   
110.
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