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Highly Selective Diphoshinoamine/Cr(III) Catalysts for Ethylene Tetramerization

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Chinese Chemical Letters 2006年第3期17卷 358-360页

作者： Tao JIANG hong xia chen Ying Nan NING Wei chen School of Chemistry ＆ Chemical Daqing Petroleum Institute Daqing 163318 SINOPEC Beijing Research Institute of Chemical Industry Beijing 100013

Two novel diphoshinoamine ligands have been synthesized. Combination of Cr（Ⅲ） and methylaluminoxane（MAO） generated active catalytic system which can catalyze tetramerization of ethylene with high catalytic activi... 详细信息

关键词： Ethylene tetramerization 1-octene Cr(Ⅲ) diphoshinoamine MAO catalyst

Comparison of different preoperative objective nutritional indices for evaluating 30-d mortality and complications after liver transplantation

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World Journal of Gastrointestinal Surgery 2024年第1期16卷 143-154页

作者： Chuan Li hong-xia chen Yan-Hua Lai Department of Transplantation People’s Hospital of Guangxi Zhuang Autonomous RegionNanning 530021Guangxi Zhuang Autonomous RegionChina Department of Clinical Pharmacy People’s Hospital of Guangxi Zhuang Autonomous RegionNanning 530021Guangxi Zhuang Autonomous RegionChina

BACKGROUND The nutritional status is closely related to the prognosis of liver transplant re-cipients,but few studies have reported the role of preoperative objective nutri-tional indices in predicting liver transplant *** To compare the predictive value of various preoperative objective nutritional indicators for determining 30-d mortality and complications following liver transplantation(LT).METHODS A retrospective analysis was conducted on 162 recipients who underwent LT at our institution from December 2019 to June *** This study identified several independent risk factors associated with 30-d mor-tality,including blood loss,the prognostic nutritional index(PNI),the nutritional risk index(NRI),and the control nutritional *** 30-d mortality rate was 8.6%.Blood loss,the NRI,and the PNI were found to be independent risk factors for the occurrence of severe postoperative *** NRI achieved the highest prediction values for 30-d mortality[area under the curve(AUC)=0.861,P<0.001]and severe complications(AUC=0.643,P=0.011).Compared to those in the high NRI group,the low patients in the NRI group had lower preoperative body mass index and prealbumin and albumin levels,as well as higher alanine aminotransferase and total bilirubin levels,Model for End-stage Liver Disease scores and prothrombin time(P<0.05).Furthermore,the group with a low NRI exhibited significantly greater incidences of intraabdominal bleeding,primary graft nonfunction,and *** The NRI has good predictive value for 30-d mortality and severe complications following *** NRI could be an effective tool for transplant surgeons to evaluate perioperative nutritional risk and develop relevant nutritional therapy.

关键词： Liver transplantation Nutritional indicator Complications Prognosis Nutrition assessment

Study on the oscillating phenomena of electrical potential across a liquid membrane

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Chinese Chemical Letters 2007年第3期18卷 309-312页

作者： Jin Zhang Gao hong xia Dai Hua chen Jie Ren Wu Yang Chemistry ＆ Chemical Engineering College Northwest Normal University Lanzhou 730070 China

The electrical oscillations across a liquid membrane in water/oil/water system was studied with octanol as oil phase by introducing two opposite charged surfactants in oil and aqueous phase, respectively. The sustained and rhythmic oscillation was observed. To a certain extent, the features of the oscillation （e.g. induction time, frequency, life time and orientation of the pulse pikes） strongly depend on the property of surfactant, dissolved in octanol. The mechanism may be explained by the formation and destruction of dual-ion surfactant membrane accompanying with emulsification at the interface and considering the coupling effect of diffusion and associated reaction in the vicinity of the interface.

关键词： Liquid membrane Chemical oscillation Electrical potential Surfactant

Influence of transverse mode on retinal spot size and retinal injury effect:A theoreticalan alysis on 532-nm laser

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Journal of Innovative Optical Health Sciences 2014年第3期7卷 31-39页

作者： Jia-Rui Wang Guang-Yuan Yu Zai-Fu Yang Lu-Guang Jiao hong-xia chen xian-Biao Zou Department of Laser and Electromagnetic BiologyBeijing Institute of Radiation Medicine Beijing 100850P.R.China Department of Dermatology First Affliated Hospitalof PLA General HospitalBeijing 100048P.R.China

The fundamental transverse mode(TEM00)is preferable for experimental and theoretical study on the laser-induced retinal injury effect,for it can produce the minimal retinal image andestablish the most strict laser safety *** actually lasers with higher order mode werefrequently used in both earlier and recent *** higher order mode leads to largerretinal spot size and so higher damage threshold,but there are few quantitative analyses on *** this paper,a four-surface schematic eye model is established for human and *** propagation of 532-nm laser in schematic eye is analyzed by the ABCD law of *** is shown that retinal spot size increases with laser transverse mode *** relativelower mode order,the retinal spot diameter will not exceed the minimum laser-induced retinallesion(25~30μm in diameter),and so has little effect on retinal damage *** forhigher order mode,the larger'retinal spot requires more energy to induce injury and so the damage threshold *** beam divergence is lowered,the retinal spot size decreasescorrespondingly,so the efect of mode order can be *** retinal spot size of macaqueis slightly smaller than that of human and the ratio bet ween them is independent of mode *** conclude that the laser mode order has significant influence on retinal spot size but limitedinfluence on the retinal injury ffect.

关键词： Laser transverse mode four-surface schematic eye retinal spot size retinal injuryeffect.

Curcumin inhibits hepatitis B virus infection by downregulating ccc DNA-bound histone acetylation

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World Journal of Gastroenterology 2017年第34期23卷 6252-6260页

作者： Zhi-Qiang Wei Yong-hong Zhang Chang-Zheng Ke hong-xia chen Pan Ren Yu-Lin He Pei Hu De-Qiang Ma Jie Luo Zhong-Ji Meng Institute of Biomedical Research Taihe HospitalHubei University of Medicine Department of Infectious Diseases Taihe HospitalHubei University of Medicine Institute of Wudang Chinese Medicine Taihe HospitalHubei University of Medicine Hubei University of Chinese Medicine Department of pharmacy Zhongnan Hospital of Wuhan University Center for Evidence-Based Medicine and Clinical Research Taihe HospitalHubei University of Medicine

AIM To investigate the potential effect of curcumin on hepatitis B virus(HBV) covalently closed circular DNA(ccc DNA) and the underlying *** A Hep G2.2.15 cell line stably transfected with HBV was treated with curcumin, and HBV surface antigen(HBs Ag) and e antigen(HBe Ag) expression levels were assessed by ELISA. Intracellular HBV DNA replication intermediates and ccc DNA were detected by Southern blot and real-time PCR, respectively. The acetylation levels of histones H3 and H4 were measured by Western blot. H3/H4-bound ccc DNA was detected by chromatin immunoprecipitation(Ch IP) assays. The deacetylase inhibitors trichostatin A and sodium butyrate were used to study the mechanism of action for curcumin. Additionally, short interfering RNAs(si RNAs) targeting HBV were tested along with *** Curcumin treatment led to time-and dose-dependent reductions in HBs Ag and HBe Ag expression and significant reductions in intracellular HBV DNA replication intermediates and HBV ccc DNA. After treatment with 20 μmol/L curcumin for 2 d, HBs Ag and ccc DNA levels in Hep G2.2.15 cells were reduced by up to 57.7%(P < 0.01) and 75.5%(P < 0.01), respectively, compared with levels in non-treated cells. Meanwhile, time-and dose-dependent reductions in the histone H3 acetylation levels were also detected upon treatment with curcumin, accompanied by reductions in H3-and H4-bound ccc DNA. Furthermore, the deacetylase inhibitors trichostatin A and sodium butyrate could block the effects of curcumin. Additionally, transfection of si RNAs targeting HBV enhanced the inhibitory effects of *** Curcumin inhibits HBV gene replication via downregulation of ccc DNA-bound histone acetylation and has the potential to be developed as a ccc DNA-targeting antiviral agent for hepatitis B.

关键词： Curcumin Hepatitis B virus Covalently closed circular DNA Histone deacetylation

A New Construction Method for the Dual Tree Complex Wavelet Based on Direction Sensitivity

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自动化学报 2006年第1期32卷 47-53页

作者： WANG hong-xia chen Bo chenG Li-Zhi Department of Mathematics ＆ System Science National University of Defense Technology Changsha 410073

The conception of 'main direction' of multi-dimensional wavelet is established in this paper, and the capabilities of several classical complex wavelets for representing directional singularities are investigated based on their main directions. It is proved to be impossible to represent directional singularities optimally by a multi-resolution analysis (MRA) of L2(R2). Based on the above results, a new algorithm to construct Q-shift dual tree complex wavelet is proposed. By optimizing the main direction of parameterized wavelet filters, the difficulty in choosing stop-band frequency is overcome and the performances of the designed wavelet are improved too. Furthermore, results of image enhancement by various multi-scale methods are given, which show that the new designed Q-shift complex wavelet do offer significant improvement over the conventionally used wavelets. Direction sensitivity is an important index to the performance of 2D wavelets.

关键词：复合微波对偶树图象增加灵敏性

Endoscopic management of gastrointestinal smooth muscle tumor

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World Journal of Gastroenterology 2007年第36期13卷 4897-4902页

作者： xiao-Dong Zhou Nong-Hua Lv hong-xia chen Chong-Wen Wang Xuan Zhu Ping Xu You-xiang chen Department of Gastro- enterology First Affiliated Hospital of Nanchang UniversityNanchang 330006Jiangxi ProvinceChina Department of Gynecology and Obstetrics First Affiliated Hospital of Nanchang UniversityNanchang 330006Jiangxi ProvinceChina

AIM: To systematically evaluate the efficacy and safety of endoscopic resection of gastrointestinal smooth muscle tumors (SMTs, including leiomyoma and leiomyosarcoma) and to review our preliminary experiences on endoscopic diagnosis of gastrointestinal SMTs. METHODS: A total of 69 patients with gastrointestinal SMT underwent routine endoscopy in our department. Endoscopic ultrasonography (EUS) was also performed in 9 cases of gastrointestinal SMT. The sessile submucosal gastrointestinal SMTs with the base smaller than 2 cm in diameter were resected by "pushing" technique or "grasping and pushing" technique while the pedunculated SMTs were resected by polypectomy. For those SMTs originating from muscularis propria or with the base size ≥ 2 cm, ordinary biopsy technique was performed in tumors with ulcers while the "Digging" technique was performed in those without ulcers. RESULTS: 54 cases of leiomyoma and 15 cases of leiomyosarcoma were identified. In them, 19 cases of submucosal leiomyoma were resected by "pushing" technique and 10 cases were removed by "grasping and pushing" technique. Three cases pedunculated submucosal leiomyoma were resected by polypectomy. No severe complications developed during or after the procedure. No recurrence was observed. The diagnostic accuracy of ordinary and the "Digging" biopsy technique was 90.0% and 94.1%, respectively. CONCLUSION: Endoscopic resection is a safe and effective treatment for leiomyomas with the base size ≤2 cm. The "digging" biopsy technique would be a good option for histologic diagnosis of SMTs.

关键词： Gastrointestinal Smooth muscle tumor Endoscopy Endoscopic ultrasonography Management

Effects of decline in renal function with age on the outcome of asymptomatic carotid plaque in healthy adults： a 5-year follow-up study

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Chinese Medical Journal 2012年第15期125卷 2649-2657页

作者： JIANG Shi-min SUN Xue-feng GU hong-xia chen Yun-shuang XI Chun-sheng QIAO Xi chen xiang-mei Department of Nephrology Chinese People's Liberation ArmyGeneral Hospital State Key Laboratory of Kidney Disease Beijing100853 China

Background It has been long suggested that abnormal clinical factors in the body, such as dyslipidemia and diabetes, can affect the presence of atherosclerosis. However, few studies on the effect of factors within the normal range, such as the loss of renal function with age, on the prevalence of atherosclerosis are few know in healthy individuals. The aim of this study was to investigate risk factors affecting the presence of asymptomatic carotid plaques in a middle-aged and elderly healthy population. Methods In this regard, we prospectively evaluated 245 healthy individuals （98 males and 147 females） at baseline and after 5 years. Changes in the presence of carotid plaque between 2003 and 2008 were categorized into four groups, i.e. subjects without plaque at entry （n=165）： Group 1 （without plaque on two occasions, n=129） and Group 2 （with nascent plaque at follow-up, n=36）; subjects with plaque at entry （n=80）; Group 3 （with plaque regression at follow-up, n=29） and Group 4 （with plaque on two occasions, n=51）. Results Univariate analysis showed that the positive rate of carotid plaques in males was higher than that in females at the baseline, and that a significantly inverse correlation existed between the prevalence rate of plaque and aging. Logistic regression analysis of cross-sectional research showed that independent risk factors for the prevalence of atherosclerosis were male gender, lower estimated glomerular filtration rate （eGFR） and higher low-density lipoprotein cholesterol （LDL-C） at the baseline, and older age and lower eGFR were involved in the presence of carotid plaques at follow-up point. However, logistic regression analysis of the longitudinal data showed that older age, decreased eGFR and increased systolic blood pressure （SBP） independently predicted the presence of carotid plaques after 5 years in subjects without plaque at entry. In addition, in subjects with plaque at entry, age, changes in eGFR and the baseline levels of serum albumin （

关键词： carotid plaque estimated glomerular filtration rate, risk factors epidemiology

Stable copper boron–imidazolate cage as Cu-riched enzyme for highly efficient electrocatalytic CO2 reduction to ethylene

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Science China Chemistry 2025年

作者： Jun-Qiang chen Qiao-hong Li Qin-Long hong Ping Shao Hai-xia Zhang Jian Zhang State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences

Single-atom catalyst has garnered widespread attention to mimic mature enzymes due to its well-defined atomic structure and coordination environments. However, since the carbon–carbon（C–C） coupling reactions require synergistic catalysis of multiple sites, single-atom catalysts suffer from insufficient active sites and unclear reaction mechanisms. Controlling the reaction intermediates in a precisely targeted pocket through careful metal–organic cage design is therefore crucial. Here, we prepare a tetrahedral [Cu6L4]-type boron–imidazolate cage integrating highly active Cu sites and optimized cavity, which exhibits enzyme like specific catalytic performance in electrochemical CO2reduction reaction（CO2RR） to enhance the selectivity of *** analyses and computational calculations suggest that the single Cu site together with neighboring boron–imidazolate ligands provides suitably synergistic effects that enable the energetically favorable formation of an *COCHO intermediate, a key step determining selectivity. As a result, the [Cu6L4]-type cage of BIC-145 achieves a Faradaic efficiency of 28% for C2H4maintaining an average current density of -3.54 mA cm-2over a 5-hour electrolysis period. This work represents the first example for studying single-metal site catalysts with ultra-low coordination numbers through the rational design of metal–organic cages.

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