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International Ophthalmology - To investigate the retinal microvascular and choroidal thickness changes in eyes with active Beh?et’s disease posterior uveitis and post-remission. A...  相似文献   
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Room-temperature ferromagnetism in the large and direct bandgap diluted magnetic semiconductor zinc oxide (ZnO) is attributed to the intrinsic defects and p-orbital–p-orbital (p–p) coupling interaction. However, due to oxidation, the ferromagnetism induced by defects is unstable. In the present work, the solution process synthesis route was utilized to grow pristine and bismuth-doped, highly crystalline ZnO nanowire (ZnO NW)-based samples. The FE-SEM images showed that the grown ZnO NWs have a preferred orientation along the c-axis in the (001) direction due to the anisotropic crystal nature of ZnO. X-ray photoelectron spectroscopy (XPS) confirmed the presence of Bi, and at a higher doping content, the bismuth oxide phase appeared. The XRD patterns showed the wurtzite crystal structure, and the large intensity of the (002) peak suggests that most of the reflection was from the top hexagonal face of the NWs, and thus, the wires are predominantly aligned along the c-axis. The TEM analysis further confirmed the crystal growth direction along the (001) direction. The UV-Visible absorption and PL measurements also showed a decrease in the bandgap with an increase in doping concentration, which may be associated with the sp–d exchange interaction between the localized d-electrons and band electrons of the Bi ions. Bi-doping tended to increase the PL intensity in the visible region. The magnetic properties measured by SQUID at 4 and 300 K showed ferromagnetic behaviour for both the pristine and Bi-doped samples. However, the saturation magnetization for the Bi-doped samples was higher compared to that of the pristine ZnO samples until the threshold doping value. The obtained results demonstrated that Bi-doping can be used to tune both the optical and magnetic properties of ZnO NWs, hence paving the way for future spintronics and spin-polarized optoelectronics applications.

Room-temperature ferromagnetism in the large and direct bandgap diluted magnetic semiconductor zinc oxide (ZnO) is attributed to the intrinsic defects and p-orbital–p-orbital (p–p) coupling interaction.  相似文献   
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Introduction

Lymph node dissection (LND) has been advocated by oncologic surgeons to completely eradicate cancer. However, evidence for that strategy is solely based on poor quality data. Some randomized studies done outside the field of urology failed to show any benefit to LND. Our objective was to evaluate whether LND at the time of removal of prostate, kidney and urothelial carcinomas results in a survival benefit.

Methods

For that purpose, we performed a systematic literature review.

Results

For kidney cancer, LND might be able to cure some patients with N+ disease. In N0 patients, although a randomized trial has been completed, the value of LND remains uncertain. LND at the time of radical prostatectomy can be useful in some patients with lymph node invasion. However, studies on the impact of LND in pN0 patients are retrospective and conflictive. Extended LND has been recommended when performing a radical cystectomy based on improved outcomes observed in retrospective studies. However, these studies are limited by selection biases and results of ongoing randomized trials will specify the template and the advantages of LND when removing a bladder cancer. Recent data of large series of radical nephro-ureterectomies for upper tract urothelial carcinomas are conflicting. Some found a benefit of LND in N0 patients while others did not.

Conclusion

The studies that support LND at the time of surgery for prostate, kidney and urothelial carcinomas have low level of evidence. This should encourage urologists to design and perform well-designed randomized trials to assess the potential survival impact of a commonly done procedure.  相似文献   
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Background

Both our teams were the first to implement pediatric robotic surgery in France. The aim of this study was to define the key points we brought to light so other pediatric teams that want to set up a robotic surgery program will benefit.

Methods

We reviewed the medical records of all children who underwent robotic surgery between Nov 2007 and June 2011 in both departments, including patient data, installation and changes, operative time, hospital stay, intraoperative complications, and postoperative outcome. The department’s internal organization, the organization within the hospital complex, and cost were evaluated.

Results

A total of 96 procedures were evaluated. There were 38 girls and 56 boys with average age at surgery of 7.6 years (range, 0.7–18 years) and average weight of 26 kg (range, 6–77 kg). Thirty-six patients had general surgery, 57 patients urologic surgery, and 1 thoracic surgery. Overall average operative time was 189 min (range, 70–550 min), and average hospital stay was 6.4 days (range, 2–24 days). The procedures of 3 patients were converted. Median follow-up was 18 months (range, 0.5–43 months). Robotic surgical procedure had an extra cost of €1934 compared to conventional open surgery.

Conclusions

Our experience was similar to the findings described in the literature for feasibility, security, and patient outcomes; we had an overall operative success rate of 97 %. Three main actors are concerned in the implementation of a robotic pediatric surgery program: surgeons and anesthetists, nurses, and the administration. The surgeon is at the starting point with motivation for minimally invasive surgery without laparoscopic constraints. We found that it was possible to implement a long-lasting robotic surgery program with comparable quality of care.  相似文献   
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