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Aim Diarrhoea with urgency is a debilitating long‐term complication of ileal pouch anal anastomosis (IPAA) after a proctocolectomy. Somatostatin analogues are used to control diarrhoea and high‐output ostomies. Hence, we designed a prospective, double‐blind, crossover trial to explore the efficacy and tolerability of octreotide to reduce diarrhoea in adult patients with IPAA. Method Patients were randomized to octreotide subcutaneously (SC), 500 μg three times daily (t.i.d.), or matching placebo SC for 7 days. Responders (a reduction in stool frequency of three or more stools per 24‐h period and with a reduction in stool frequency of at least 30% after 7 days of treatment compared with baseline; the primary end‐point) remained in the same group and nonresponders could cross over to the alternative treatment for 7 days. Open‐label octeotide LAR 30 mg was offered to all responders on day 14. Flexible pouchoscopy with biopsies was performed at baseline in all patients and was repeated on days 7 and 14 in patients with pouchitis. Results Fifteen patients (11 men, median age 52 years), all with ulcerative colitis, were randomized. Three patients were withdrawn for side effects during the blinded phase. Response was achieved by two of 12 and two of 11 patients treated with octreotide or placebo, respectively (including crossover, P = 0.9). The median stool frequency remained stable in both groups [Δoctreotide: 0 (IQR, ?4 to 0), Δplacebo: ?1 (IQR, ?1 to 1), P = 0.45]. Octreotide had no effect on the modified pouch disease activity index (mPDAI), and pouchitis persisted in five of six subjects with pouchitis at onset. One subject received open‐label octreotide LAR. Conclusion Octreotide has no clear beneficial effect on the stool pattern or on pouchitis severity in patients with high stool frequency after IPAA.  相似文献   
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Thin film solar cells (TFSCs) suffer from poor light absorption due to their small thickness, which limits most of their practical applications. Surface plasmons generated by plasmonic nanoparticles offer an opportunity for a low-cost and scalable method to optically engineer TFSCs. Here, a systematic simulation study is conducted to improve the absorption efficiency of amorphous silicon (a-Si) by incorporating double sided plasmonic bi-metallic (Al–Cu) nanogratings. The upper pair of the gratings together with an antireflection coating are responsible for minimizing the reflection losses and enhancing the absorption of low wavelength visible light spectrum in the active layer. The bottom pairs are accountable for increasing the absorption of long wavelength photons in the active layer. In this way, a-Si, which is a poor absorber in the long wavelength region, is now able to absorb broadband light from 670–1060 nm with an average simulated absorption rate of more than 70%, and improved simulated photocurrent density of 22.30 mA cm−2, respectively. Moreover, simulation results show that the proposed structure reveals many other excellent properties such as small incident angle insensitivity, tunability, and remarkable structural parameters tolerance. Such a design concept is quite versatile and can be extended to other TFSCs.

Thin film solar cells (TFSCs) suffer from poor light absorption due to their small thickness, which limits most of their practical applications.  相似文献   
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Introduction

Gallstones are known to be associated with premalignant changes in the gallbladder epithelium that range from atypical hyperplasia, metaplasia, dysplasia to carcinoma. Recognition of factors associated with these changes in patients with gallstones can potentially be helpful in identifying patients to whom prophylactic cholecystectomy can be offered to reduce the chances of developing carcinoma.

Objective

To identify factors associated with premalignant epithelial changes including atypical hyperplasia, metaplasia, and dysplasia in gallbladder mucosa in patients with chronic calculus cholecystitis.

Materials and methods

This was retrospective case–control study conducted over a period of 10 years from 2004 to 2014. Cases were patients with reported histopathological premalignant epithelial changes along with chronic calculus cholecystitis, and controls were patients without premalignant epithelial changes but chronic calculus cholecystitis. Controls were twice the number of the cases.

Results

Over study period, 92 patients were reported to have premalignant epithelial changes on gall bladder histopathology for whom 184 controls were selected. Of cases, 61 (66%) patients had atypical hyperplasia, while metaplasia and dysplasia were present in 26 (28%) and 5 (5%) cases, respectively. Mean age was 47.5 ± 14.5 years, and 74% of the study population were female. Wall thickness of more than 3 mm (OR = 4.14, p value < 0.001) turned out to be statistically significant independent variables associated with premalignant lesions in gallbladder mucosa.

Conclusion

Odds of premalignant epithelial change in gall bladder mucosa in patients with gall bladder wall thickness of more than 3 mm is four times the odds of patients with wall thickness less than 3 mm, and the effect is statistically significant. Prophylactic cholecystectomy should be considered for this group of patients.
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