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Transforming a Two-dimensional Layered Insulator into a Semiconductor or a Highly Conductive Metal through Transition Metal Ion Intercalation

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Chinese Physics Letters 2021年第5期38卷 89-93页

作者： Xiu Yan Wei-Li Zhen Shi-Rui Weng Ran-Ran Zhang Wen-ka Zhu Li Pi Chang-Jin Zhang High Magnetic Field Laboratory Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China Institutes of Physical Science and Information Technology Anhui UniversityHefei 230601China

Atomically thin two-dimensional(2d) materials are the building bricks for next-generation electronics and optoelectronics, which demand plentiful functional properties in mechanics, transport, magnetism and *** electronic devices, not only metals and high-performance semiconductors but also insulators and dielectric materials are highly desirable. Layered structures composed of 2d materials of different properties can be delicately designed as various useful heterojunction or homojunction devices, in which the designs on the same material(namely homojunction) are of special interest because preparation techniques can be greatly simplified and atomically seamless interfaces can be achieved. We demonstrate that the insulating pristine ZnPS_3, a ternary transition-metal phosphorus trichalcogenide, can be transformed into a highly conductive metal and an n-type semiconductor by intercalating Co and Cu atoms, respectively. The field-effect-transistor(FET) devices are prepared via an ultraviolet exposure lithography technique. The Co-ZnPS_3 device exhibits an electrical conductivity of 8 × 10^(4) S/m, which is comparable to the conductivity of graphene. The Cu-ZnPS_3 FET reveals a current ON/OFF ratio of 1-05 and a mobility of 3 × 10^(-2 )cm^(2)·V^(-1)·s^(-1). The realization of an insulator, a typical semiconductor and a metallic state in the same 2d material provides an opportunity to fabricate n-metal homojunctions and other in-plane electronic functional devices.

关键词： Transforming a Two-dimensional Layered Insulator into a Semiconductor or a Highly Conductive Metal through Transition Metal Ion Intercalation

Management of Recurrent Large Bowel Obstruction due to Stent Occlusion by ‘Stent-Over-Stent’: A Case Report and Literature Review

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Surgical Science 2011年第8期2卷 418-421页

作者： d. Yi-Po Tsang Hester Yui-Shan Cheung Cliff Chi-Chiu Chung Michael ka-Wah Li 不详

Endoscopic stenting for malignant large bowel obstruction is common nowadays. However, recurrent obstruction secondary to stent occlusion due to tumour ingrowth or overgrowth might occur. We reported a case of a 70-year-old man with large bowel obstruction initially treated with colonic stenting. It was complicated with recurrent intestinal obstruction, with colonoscopy showing stent blockage by tumour ingrowth over distal part of the stent. Successful endoscopic implantation of additional colonic stent over the old stent was achieved and intestinal obstruction was resolved afterwards.

关键词： Colon Intestinal Obstruction and Stenting

Effect of herpesvirus infection on pancreatic duct cell secretion

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World Journal of Gastroenterology 2005年第38期11卷 5997-6002页

作者： Péter Hegyi Balázs rdg Zoltán Rakonczai Jr Tamás Takács János Lonovics Annamária Szabolcs Réka Sári András Tóth Julius G Papp András Varró Mária k kovács Mike A Gray Barry E Argent Zsolt Boldogki First department of Medicine department of Biology division of Cardiovascular Pharmacology School of Cell and Molecular Biosciences

AIM： To examine the effect of acute infection caused by herpesvirus （pseudorabies virus, PRV） on pancreatic ductal secretion. METHOdS： The virulent Ba-dupGreen （BdG） and non- virulent ka-RREp01acgfp （kEG） genetically modified strains of PRV were used in this study and both of them contain the gene for green fluorescent protein （GFP）. Small intra/ interlobular ducts were infected with BdG virus （10^7 PFU/mL for 6 h） or with kEG virus （10^10 PFU/mL for 6 h）, while non-infected ducts were incubated only with the culture media. The ducts were then cultured for a further 18 h. The rate of HCO3 secretion [base efflux -λ（B）] was determined from the buffering capacity of the cells and the initial rate of intracellular acidification （1） after sudden blockage of basolateral base loaders with dihydro-4,4,- diisothiocyanatostilbene-2,2,-disulfonic acid （500 μmol/L） and amiloride （200 μmol/L）, and （2） after alkali loading the ducts by exposure to NH4Cl. All the experiments were performed in HCO3-buffered Ringer solution at 37 ℃ （n = 5 ducts for each experimental condition）. Viral structural proteins were visualized by immunohistochemistry. Virallyencoded GFP and immunofluorescence signals were recorded by a confocal laser scanning microscope.RESULTS： The BdG virus infected the majority of accessible cells of the duct as judged by the appearance of GFP and viral anUgens in the ductal cells. kEG virus caused a similarly high efficiency of infection. After blockage of basolateral base loaders, BdG infection significantly elevated -λB-） 24 h after the infection, compared to the non-infected group. However, kEG infection did not modify -λB-）. After alkali loading the ducts, -λB-） was significantly elevated in the BdG group compared to the control group 24 h after the infection. As we found with the inhibitor stop method, no change was observed in the group kEG compared to the non-infected group. CONCLUSION： Incubation with the BdG or kEG strains of PRV results in an effective i

关键词： Pancreas Hypersecretion ductal cells Infection Pseudorabies virus

The First Cases of Laparoscopic Colectomy for Cancer in Ziguinchor Peace Hospital

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Surgical Science 2023年第8期14卷 550-556页

作者： Omar Sow Aissé Thioubou Reymond Saidy Aboubacar Traoré Modou d. Ndiaye Mouhamadou L. Gueye Ibrahima ka Madieng dieng department of Surgery Peace Hospital Assane Seck University Ziguinchor Senegal department of General Surgery Cheikh Anta Diop University Dakar Senegal

Laparoscopic colectomy is a standardized technique for the curative treatment of colon cancer, based on the principles of carcinological surgery. It is rarely performed in our region but common practice in developed countries. We conducted a retrospective study of the first 4 cases of laparoscopic colectomy for cancer. The patients were 3 men and 1 woman, with a mean age of 54.2 years. Of the 4 cancers, 3 were localized to the sigmoid and one to the cecum. The main symptom was rectal bleeding. Total colonoscopy with biopsy was performed in 3 patients and the histological type was a lieberkühnian, infiltrative, moderately differentiated adenocarcinoma. Thoraco-abdomino-pelvic computed tomography (TAP CT) was performed in all the cases. Three patients were presented to the multidisciplinary team (MdT) prior to surgery. The operations were one right hemicolectomy and three left hemicolectomies. The mean operative time was 182.25 min [152 - 210]. Average blood loss was estimated at 200 cc. The average hospital stay was 4.71 days. Cancer staging was classified as stage I in 1 case (p T1N0M0) and stage III in 3 cases (pT3N1Mx, pT3N2Mx). Resection margins were healthy. The number of lymph nodes removed was 12, 14, 17 and 13 respectively. Conclusion: This is a safe and reproducible technique, but requires a much higher cost than laparotomy.

关键词： Colectomy Cancer Laparoscopy Ziguinchor

different cell kinetic changes in rat stomach cancer after treatment with celecoxib or indomethacin: Implications on chemoprevention

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World Journal of Gastroenterology 2005年第1期11卷 41-45页

作者： JunYu Bao-dongTang Waik.Leung ka-FaiTo AlfaH.C.Bai Zhi-RongZeng Po-kiMa MinnieY.Y.Go Pin-JinHu JosephJ.Y.Sung departmentofMedicine&Therapeutics PrinceofWalesHospitalTheChineseUniversityofI-longKongShatinHongKongChina departmentofGastroenterology TheFirstAffiliatedHospitalSunYat-SenUniversityofMedicalSciencesGuangzhou510080GuangdongProvinceChina departmentofAnatomical&CellularPathology PrinceofWalesHospitalTheChineseUniversityofHongKongShatinHongKongChina

AIM: Mechanisms underlying the chemopreventive effects of cyclooxygenase (COX) inhibitors remain elusive. We have previously shown that celecoxib but not indomethacin could prevent carcinogen-induced gastric cancer development in Wistar rats. This chemopreventive effect appeared to be independent of COX-2 and prostaglandin (PG) E2 suppression since the lowest PGE2 was obtained in indomethacin *** study compared the cell kinetic changes in stomachs of rats after treatment with celecoxib (5, 10, 20 mg/(kg·d)) or indomethacin (3 mg/(kg·d)) to gain more insights into the chemopreventive ***: The apoptosis and proliferation indexes in gastric tumor, adjacent non-cancer tissues and normal gastric tissues were determined. Apoptosis was quantified by apoptotic nuclei counting and TUNEL, whereas proliferation was determined by ki67 ***: Treatment with either celecoxib or indomethacin inhibited gastric tumor proliferation by more than 65% (P＜0.02). However, celecoxib caused a dose-dependent increase in apoptosis (P＜0.05) which was not seen in indomethacin-treated tumors (P = 0.54). The highest apoptosis to proliferation ratio was seen in tumors treated with celecoxib at 10 mg/(kg·d). Treatment with this dose of celecoxib was associated with the lowest incidence of gastric cancer ***: Our findings suggest that the difference in chemopreventive effects of indomethacin and celecoxib in this animal model of gastric carcinogenesis is largely due to the differential cell kinetic changes, which does not correlate with the degree of COX-2 and PG suppression.

关键词： Stomach cancer Celecoxib Indomethacin Cell kinetics

Response of mollusk assemblages from the Luochuan loess section to orbital forcing since the last 250 ka

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Chinese Science Bulletin 2000年第17期45卷 1617-1622页

作者： d.d.Rousseau Laboratoire de Palynologie-URA 327 University Montpellier Ⅱ 34095 Montpellier France

This note presents a new result of terrestrial mollusk study from the Luochuan loesssection since the last 250 ka. A total of 213 samples, taken at intervals of 10 cm in the S0-L3 portion, were analyzed for fossil mollusks. Generally, 150-600 individuals were counted in each sample. According to the distribution of mollusk fossil assemblages in the loess section, 11 mollusk fossil zones have been recognized, representing different climatic and ecological conditions. Three main ecological groups were identified according to the temperature and moisture requirements of each taxon. The cold-aridiphilous group shows maxima at about 240-220, 190-182, 150-140 and 74 -66 ka BP. The thermo-humidiphilous set has high abundances for at least 6 times in the section at about 246-240, 220-216, 170-158, 92-86, 60-44 and 10 kaBP. Our results show that variations in mollusk ecological groups are related with changes in the Earth orbital parameters at the 41 and 20 ka frequencies. Maxima in thermo-humidiphilous taxa

关键词： mollusk assemblage loess orbital forcing.

A stoichiometric terbium-europium dyad molecular thermometer: energy transfer properties

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Light(Science & Applications) 2018年第1期7卷 141-150页

作者： Guochen Bao ka-Leung Wong dayong Jin Peter A.Tanner department of Chemistry Hong Kong Baptist UniversityKowloon TongHong Kong SARPeople’s Republic of China Institute for Biomedical Materials and devices(IBMd) Faculty of ScienceUniversity of Technology SydneySydneyNSW 2007Australia School of Mathematical and Physical Sciences Faculty of ScienceUniversity of Technology SydneySydneyNSW 2007Australia

The optical thermometer has shown great promise for use in the fields of aeronautical engineering,environmental monitoring and medical ***-referencing lanthanide thermo-probes distinguish themselves because of their accuracy,calibration,photostability,and temporal dimension of ***,the use of conventional lanthanidedoped materials is limited by their poor reproducibility,random distance between energy transfer pairs and interference by energy migration,thereby restricting their ***,a strategy for synthesizing hetero-dinuclear complexes that comprise chemically similar lanthanides is introduced in which a pair of thermosensitive dinuclear complexes,cycTb-phEu and cycEu-phTb,were *** structures were geometrically optimized with an internuclear distance of approximately 10.6Å.The sensitive linear temperature-dependent luminescent intensity ratios of europium and terbium emission over a wide temperature range(50–298 k and 10–200 k,respectively)and their temporal dimension responses indicate that both dinuclear complexes can act as excellent self-referencing *** energy transfer from Tb^(3+)to Eu^(3+)is thermally activated,with the most important pathway involving the ^(7)F_(1) Eu^(3+)J-multiplet at room *** energy transfer from the antenna to Eu^(3+)was simulated,and it was found that the most important ligand contributions to the rate come from transfers to the Eu^(3+)upper states rather than direct ligand–metal transfer to 5d1 or *** the first molecular-based thermometer with clear validation of the metal ratio and a fixed distance between the metal pairs,these dinuclear complexes can be used as new materials for temperature sensing and can provide a new platform for understanding the energy transfer between lanthanide ions.

关键词： temperature. lanthanide transfer

The Saturation Characteristics of Glucose Transport in Bovine Retinal Pigment Epithelium

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眼科学报 1998年第3期14卷 126-129页

作者： Chi Ho To kin kwok Cheung Shing Hon Chiu Hon Ming Lai ka Shun Lung Laboratory of Ocular Physiology and Biochemistry Department of Optometry and Radiography The Hong Kong Polytechnic UniversityHung HomKawloonHong Kong

Purpose:To study the saturation characteristics of the glucose transport across the bovine retinal pigment epithelium(RPE).Methods:The bovine RPE preparations were munted with a modified Ussing *** L-[^(3)H]-glucose and 3-0-methyl-d-[^(14)C]-glucose fluxes across the RPE from the choroid to retina were studied at different glucose ***:The glucose transport was found to be stereospecific,with 3-0-methyl-d-glucose(MdG)being transported about three times faster than *** glucose transport showed typical saturation characteristics in Michaelis-Menten *** V_(max)and the k_(m)of corrected MdG were 2452 nmol cm^(-2)h^(-1)and 30.8 mM *** was shown that the glucose transport system was saturated at 61.6 ***:The saturation characteristics of the corrected MdG flux suggested that the capacity of glucose transport through the bovine RPE is immense.

关键词： ussing chamber retinal pigment epithelium glucose transport saturation kinetics

Insulin is necessary for the hypertrophic effect of cholecystokinin-octapeptide following acute necrotizing experimental pancreatitis

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World Journal of Gastroenterology 2004年第15期10卷 2275-2277页

作者： Péter Hegyi Zoltán RakonczayJr Réka Sári László Czakó Norbert Farkas Csaba Góg József Németh János Lonovics Tamás Takács First department of Medicine Faculty of MedicineUniversity of Szeged Szeged H6722Hungary School of Cell and Molecular BiosciencesMedical SchoolUniversity of NewcastleNewcastle upon TyneNE2 4HHUnited Kingdom First department of Medicine Faculty of MedicineUniversity of Szeged Szeged H6722Hungary Jr.School of Cell and Molecular BiosciencesMedical SchoolUniversity of NewcastleNewcastle upon TyneNE2 4HHUnited Kingdom First department of Medicine Faculty of MedicineUniversity of Szeged Szeged H6722Hungary

AIM:In previous experiments we have demonstrated that by administering low doses of cholecystokinin-octapeptide (CCk-8),the process of regeneration following L-arginine (Arg)-induced pancreatitis is *** rats that were also diabetic(induced by streptozotocin,STZ),pancreatic regeneration was not *** aim of this study was to deduce whether the administration of exogenous insulin could in fact restore the hypertrophic effect of CCk-8 in diabetic-pancreatitic rats. METHOdS:Male Wistar rats were used for the experiments. diabetes mellitus was induced by administering 60mg/kg body mass of STZ intraperitoneally(i.p.),then,on d 8, pancreatitis was induced by 200mg/100 g body mass Arg *** at an interval of 1 *** animals were injected subcutaneously twice daily(at 7 *** 7 p.m.)with 1 μg/kg of CCk-8 and/or 2 IU mixed insulin(300g/L short- action and 700g/L intermediate-action insulin) for 14 d after pancreatitis *** this the animals were killed and the serum amylase,glucose and insulin levels as well as the plasma glucagon levels,the pancreatic mass/body mass ratio(pm/bm),the pancreatic contents of dNA,protein,amylase,lipase and trypsinogen were *** tissue samples were examined by light microscopy on paraffin-embedded sections. RESULTS:In the diabetic-pancreatitic rats treatment with insulin and CCk-8 significantly elevated pw/bm and the pancreatic contents of protein,amylase and lipase vs the rats receiving only CCk-8 ***-8 administered in combination with insulin also elevated the number of acinar cells with mitotic activities,whereas CCk-8 alone had no effect on laboratory parameters or the mitotic activities in diabetic-pancreatitic rats. CONCLUSION:despite the hypertrophic effect of CCk-8 being absent following acute pancreatitis in diabetic-rats, the simultaneous administration of exogenous insulin restored this *** results clearly demonstrate that insulin is necessary for the hypertrophic ef

关键词： Animals diabetes Mellitus, Experimental Hypoglycemic Agents Insulin Male Pancreatitis, Acute Necrotizing Rats Rats, Wistar Regeneration Research Support, Non-U.S. Gov't Sincalide