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131.
132.
Antimony telluride (Sb2Te3) thin films were prepared by a room temperature Metal–Organic Chemical Vapor Deposition (MOCVD) process using antimony chloride (SbCl3) and bis(trimethylsilyl)telluride (Te(SiMe3)2) as precursors. Pre-growth and post-growth treatments were found to be pivotal in favoring out-of-plane and in-plane alignment of the crystallites composing the films. A comprehensive suite of characterization techniques were used to evaluate their composition, surface roughness, as well as to assess their morphology, crystallinity, and structural features, revealing that a quick post-growth annealing triggers the formation of epitaxial-quality Sb2Te3 films on Si(111).

Highly oriented antimony telluride thin films are prepared by room temperature metalorganic chemical vapor deposition on Si(111).  相似文献   
133.

Objectives

To assess the accuracy of intra-rectal coil magnetic resonance imaging (ER-MRI) for staging early prostate cancer (EPC).

Materials and methods

ER-MRI was performed with the Magnetom Symphony 1.5 Tesla system. ER-MRI and pathology findings were statistically correlated.

Results

One hundred and fifty-four consecutive patients underwent radical prostatectomy (RRP) for EPC (cT1c-2 Nx M0). An average age was 66, mean PSA 11.04 µg/L (median 7.33 µg/L) and mean pathologic Gleason score 6. Pathology detected 97 out of 154 patients (63 %) as EPC and 57 cases (37 %) as extra-prostate extension (EPED) (pT3) with extra-capsular extension (ECE) (pT3a) in 41 (27 %) and seminal vesicle invasion (SVI) (pT3b) in 16 (10 %). ER-MRI staged 100 patients (65 %) as cT2 and 54 (35 %) as EPED with ECE in 37 cases (24 %) and SVI in 17 (11 %). ER-MRI sensitivity, specificity, positive predictive value, negative predictive value, overall accuracy resulted respectively 0.78, 0.96, 0.86, 0.92, 0.91 for ECE as well as 0.88, 0.98, 0.82, 0.99 and 0.97 for SVI.

Conclusion

ER-MRI was effective in detecting preoperative EPC under-staging. In the next future, multi-parametric 3-Tesla ER-MRI will be the procedure for diagnosing, staging and following-up prostate cancer patients.  相似文献   
134.
Chronic hepatitis B is prevalent in the transplant setting and may cause significant complications. Effective control of viral replication is needed. Besides lamivudine, very little data are available on safety and efficacy of other drugs. We describe our experience with adefovir dipivoxil (ADV) in eight heart transplant recipients. Studies included a baseline liver biopsy, thrice‐monthly clinical, biochemical, and virological evaluations, including genotyping and viral load, polymerase gene sequencing for resistance mutations, liver and kidney function tests, and liver ultrasound. Of eight patients, six had fibrosis score ≤2 and negative HBeAg and seven had hepatitis B virus (HBV) genotype D. Upon ADV start, median HBV‐DNA was 5.8 logs IU/mL and alanine aminotransferase (ALT) levels were mostly normal. All patients had prior mild‐to‐moderate renal functional impairment. Seven of eight patients started ADV after a previous course of lamivudine. Five of these seven patients became HBV‐DNA undetectable within eight months. One patient with low baseline viremia started ADV de novo and suppressed HBV‐DNA. Median treatment duration was 66 months. ADV daily dose was halved in one patient due to renal function worsening. No ALT flares, hypophosphatemia, liver decompensation, liver cancer, or emergence of resistance was observed. Our data suggest that ADV may be a safe and effective rescue treatment for heart transplant recipients with lamivudine‐resistant chronic hepatitis B.  相似文献   
135.

Background

SpyGlass® single-operator peroral cholangioscopy appears to be a promising technique to overcome some limitations of conventional peroral cholangioscopy. We aimed to prospectively evaluate the SpyGlass system in a cohort of patients with indeterminate biliary lesions.

Methods

Patients with indeterminate strictures or filling defects at endoscopic retrograde cholangiopancreatography (ERCP) were consecutively enrolled. After SpyGlass visual evaluation, targeted biopsies were taken with the SpyBite® and histopathological assessment was made by two experienced gastrointestinal pathologists. SpyBite-targeted biopsy results were evaluated by assessing agreement with surgical specimens and by evaluation of final, clinical follow-up-based diagnosis.

Results

Fifty-two patients participated in the study. In 7 cases, definite diagnosis (stones, varices) was made by SpyGlass endoscopic evaluation. In 42 of the remaining 45 cases, material suitable for histopathology assessment was provided by the SpyBite. Overall, a definite diagnosis was made in 49 (7 + 42; 94 %) cases. Agreement of SpyBite biopsy results with surgical specimen diagnosis was found in 38/42 (90 %) cases; sensitivity, specificity, and positive and negative predictive values were 88, 94, 96, and 85 %, respectively. Procedure-related complications consisted of one case of mild cholangitis and one case of mild pancreatitis.

Conclusions

In our series, the SpyGlass system allowed adequate biopsy sampling and definite diagnosis with high accuracy in the vast majority of patients with indeterminate biliary lesions. Its use was associated with a low complication rate. Further refinements of the technique are warranted, but the SpyGlass system has the potential to become a diagnostic standard for the assessment of indeterminate biliary lesions.  相似文献   
136.

Background

Endoluminal locoregional resection (ELRR) by transanal endoscopic microsurgery (TEM) is an alternative treatment option for T1N0 rectal cancer and for selected patients with small T2N0 rectal cancer after neoadjuvant radiochemotherapy (n-RCT). The N parameter may remain undefined after transanal surgery. This study aimed to evaluate the role of a modified sentinel lymph node technique to improve N staging that the authors named “nucleotide-guided mesorectal excision” (NGME).

Methods

The study enrolled 41 patients (24 men and 17 women) with a mean age of 70.5 years. Preoperative staging identified dysplasia with no suspicion for cancer at imaging (n = 8), dysplasia with suspected malignancy at imaging (n = 15), no suspicion of malignancy at imaging after n-RCT (n = 2), cT1N0 (n = 6), cT2N0 (n = 6), cT3N0 (n = 3), and cT3N1 (n = 1). The patients underwent ELRR by TEM with NGME. Before surgery, 99m-technetium-marked nanocolloid was injected into the peritumoral submucosa. After resection, the residual defect was probed to detect residual radioactivity. If present, hot mesorectal fat was excised.

Results

With NGME, the mesorectal lymph node harvest increased from 0 to 10. Lymph nodes were isolated in the specimen or in hot mesorectal fat of 20 patients, 8 of whom had undergone n-RCT. The mean lymph node harvest was 2.75 ± 3.01 (range 1–10) in the irradiated patients and 2.91 ± 1.62 (range 1–6) in the nonirradiated patients (p = 0.87). The average number of lymph nodes in the irradiated patients was higher than in a previous historical series.

Conclusions

The use of NGME during ELRR by TEM increases the lymph node harvest and may improve staging accuracy after transanal surgery.  相似文献   
137.
138.
139.
BackgroundThe aim of this study was to evaluate the long-term effects of laparoscopic sleeve gastrectomy (LSG) on type 2 diabetes mellitus (T2DM) and other related co-morbidities in severely obese patients.MethodsFrom May 2003 to July 2008, 33 morbidly obese diabetic patients (20 with body mass index [BMI]>50 kg/m2) underwent LSG. A total of 23 females and 10 males participated, with a mean age of 49.3±8 years, mean preoperative BMI of 52.1±8.5 kg/m2, mean fasting plasma glucose (FPG) of 143.2±47.9 mg/dL, mean glycosylated hemoglobin (HbA1c) of 7.3%±1.4%, and a mean T2DM duration of 7 years. All patients had a 36-month follow-up, and 13 had a 60-month follow-up.ResultsTwenty-nine patients (87.8%) discontinued antidiabetic medications 3 months after LSG, (mean BMI of 42.8±7.8 kg/m2; FPG of 104.5±22.1 mg/dL; HbA1c of 5.3%±.4%). At 36 months, 22 of 26 LSG patients (84.6%) had normal FPG and HbA1c values without antidiabetic therapy. At the 60-month follow-up, 10 of 13 patients (76.9%) had normal FPG and HbA1c values without antidiabetic therapy. The Framingham risk score decreased significantly from 9.7% preoperatively to 4.7% postoperatively. No new diabetic retinopathy occurred during the whole period of observation.ConclusionsThis study confirms the efficacy of LSG in the treatment of T2DM and indicates that, at both 36- and 60-month follow-ups, LSG can provide a significant percentage of treated patients with a prolonged remission of T2DM, with diminished cardiac risk factors and no development of diabetic retinopathy. These results compare favorably with those reported after standard medical therapy.  相似文献   
140.
Introduction: PLS is defined as pure upper motor neuron disease/dysfunction (PUMND) beyond 48 months after symptom onset. We know little about its early stages, but such knowledge would help to identify the mechanisms underlying PLS and ALS and determine why PLS patients seem to be protected against lower MND (LMND). Methods: We reviewed 622 MND cases during a 4‐year period and identified 34 patients with PUMND (5.4%). Results: Among 23 cases with follow‐up data/electromyograms (EMGs; 2 had only 1 EMG), 13 (57%) remained classified as PUMND, and 8 (35%) developed LMND (mean, 51.4 months after onset). Of these 8, LMND developed in 3 after 48 months from symptom onset. Patients with PUMND and LMND were more functionally impaired (P = 0.02). Separately, we identified 5 patients with PUMND who developed LMND long after 48 months (range, 50–127 months). Conclusions: PLS belongs to the ALS spectrum, and perhaps all cases eventually develop LMND. Muscle Nerve, 2013  相似文献   
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