Publications by authors named "Ke-chun Yao"

The glucoconjugation between linear chimeric α-(1→4)- and α-(1→6)-glucosidic segments exhibits functional properties throughout their structure. In this study, we enzymatically synthesized three new series of chimeric nonreducing isomaltomegalosaccharides (N-IMS-n/m), each featuring a constant n, α-(1→4)-segment (average degree of polymerization, DP = 22-25) at the nonreducing terminal, and varying m, α-(1→6)-main chain lengths (DP = 7-53). The synthesized compounds-N-IMS-25/7, N-IMS-24/19, and N-IMS-22/53-were compared to amylose (DP = 28) and previous samples of N-IMS-15/35 and D-IMS-28.

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The sequence of monomers within a polymer chain plays a pivotal role in determining the physicochemical properties of the polymer. In the copolymerization of two or more monomers, the arrangement of monomers within the resulting polymer is primarily dictated by the intrinsic reactivity of the monomers. Precisely controlling the monomer sequence in copolymerization, particularly through the manipulation of catalysts, is a subject of intense interest and poses significant challenges.

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The optimization of field-effect mobility in polymer field-effect transistors (FETs) is a critical parameter for advancing organic electronics. Today, many challenges still persist in understanding the roles of the design and processing of semiconducting polymers toward electronic performance. To address this, a facile approach to solution processing using blends of PDPP-TVT and PTPA-3CN is developed, resulting in a 3.

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The molecular structure of polymer electrets is crucial for creating diverse functionalities of organic field-effect transistor (OFET) devices. Herein, a conceptual framework has been applied in this study to design the highly photoresponsive carbazole-based copolymer electret materials for the application of photoresponsive OFET memory. As an electret layer, two 1,8-carbazole-based copolymers were utilized; the consisted of carbazole as the donor group and thiophene as the π-spacer, whereas the was further introduced as an acceptor moiety, benzothiadiazole, for comparison.

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Background: Transjugular intrahepatic portosystemic shunt (TIPS) is widely accepted as an alternative to surgery for management of complications of portal hypertension. TIPS has been used to treat portal vein thrombosis (PVT) in many centers since the 1990s. Although TIPS has good therapeutic effects on the formation of PVT, the effect of PVT on TIPS stenting has rarely been reported.

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Background: There is a close relationship between cirrhosis and hepatocellular carcinoma (HCC). Transjugular intrahepatic portosystemic shunt (TIPS) has good clinical effect in treating the complication of portal hypertension. However, because of the risk of postoperative liver failure, severe complications, and low survival rate for HCC, TIPS is contraindicated in patients with portal hypertension and liver cancer.

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Background: Transjugular intrahepatic portosystemic shunt (TIPS) is currently used for the treatment of complications of portal hypertension. The incidence of hepatic encephalopathy (HE) remains a problem in TIPS placement. It has been reported that the right branch mainly receives superior mesenteric venous blood while the left branch mainly receives blood from the splenic vein.

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Aim: To evaluate the effect of initial stent position on transjugular intrahepatic portosystemic shunt (TIPS).

Methods: We studied 425 patients from January 2004 to January 2015 with refractory ascites or variceal bleeding who required TIPS placement. Patients were randomly divided into group A (stent in hepatic vein, = 57), group B (stent extended to junction of hepatic vein and inferior vena cava, = 136), group C (stent in left branch of portal vein, = 83) and group D (stent in main portal vein, = 149).

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This study aimed to explore the mechanism of membranous ventricular septal defect complicated with tricuspid regurgitation and the significance of ventricular septal defect occlusion by echocardiography. A total of 43 patients with membranous ventricular septal defect complicated with tricuspid regurgitation were observed by echocardiography and the changes in length, area and volume of tricuspid regurgitation prior to and following ventricular septal defect occlusion were measured. There were four different mechanisms of membranous ventricular septal defect complicated with tricuspid regurgitation.

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Objective: This study was to evaluate the value of contrast-enhanced ultrasonography (CEUS) in the diagnosis and preoperative localization of insulinoma and explore the enhancement patterns of the tumors.

Methods: Unenhanced and contrast-enhanced ultrasonographic examinations of 31 patients who underwent resection of insulinomas were retrospectively reviewed. The diagnosis sensitivity and localization specificity of CEUS for insulinomas were determined.

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