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The Synthesis and Structure of Adduct of a New Schiff Base Macrocycle with Two THF: THIONE_2B_4[36]ENE-O_6N_8·2THF

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Chinese Chemical Letters 1996年第10期7卷 884-885页

作者： Lin, Zhen Guang chen, hua yang Lin, Yu Juan huang, Feng hua State Key Lab. of Struct. Chemistry Fujian Inst. Res. Struct. of Matter Fuzhou 350002 Department of Chemistry Fujian Teachers' University Fuzhou 350007

New Schiff base Macrocyclic compound of 2,3: 11, 12:20, 21:29, 30-tetrabenzo-1,13,16,19,31,34-hexaoxa-5,6,8,9,23,24,26,27-octaaza-7,25-dithione-2,3:4,5:9,10:11,12:22, 23:27,28:29,30 cyclo-[36]ene (thione2B4[36] ene-O6N8) containing THF has been prepared. It crystallizes in the monoclinic, space group P21/n. with parameters a=9.829(5) b=24.23(1), c=10.181(9), β=92.93(5)°, Z=2, V=2422(3)3, Dc=1.25gcm-3. Data collection: Rigaku AFC-5R diffractometer,(MoKα, λ=0.71069), ω /2θ scans. θmax=25°, empirical absorption correction, 4658 measured reflections, 4387 independent, 1743 observed reflections [I≥3σ(I)]. The final R=0.056. RW=0.069,S=1 .54, (Δ/σ)max=0.01,Δρmax=0.36e-3.

关键词： ENE and Macrocycle New O6N8 Schiff Structure Synthesis THIONE2B4 The Adduct THF

Improvement, Comparison, and Application of Field Measurement Methods for Grassland Vegetation Fractional Coverage

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Journal of Integrative Plant Biology 2005年第9期47卷 1074-1083页

作者： Xiao-Bing LI Yun-Hao chen hua yang Yun-Xia ZHANG College of Resources Sciences and Technology Key Laboratory of Environmental Change and Natural Disaster of the Ministry of Education Beijing Normal University Beijing 100875 China

As one of the important vegetation parameters, vegetation fractional coverage （VFC） is more difficult to measure accurately among a good many parameters of plant communities. The temperate typical steppe in the north of China was chosen for investigation in the present study and a digital camera was used to measure herb community coverage in the field, adopting methods of ocular estimation, gridding measurement, visual interpretation, supervised classification, and information extraction of color spatial transformation to calculate the VFC of images captured by the digital camera. In addition VFC calculated by various methods was analyzed and compared VFC, enabling us to propose an effective method for measuring VFC using a digital camera. The results of the present study indicate that：（i） as two common useful and effective methods of measuring VFC with a digital camera, not only does the error of estimated values of visual estimation and supervised classification vary considerably, but the degree of automatization is very low and depends, to a great extent, on the manipulator; （ii） although the method of visual interpretation may assure the precision of the calculated VFC and enable the precision of results obtained using other methods to be determined, as far as large quantities of data are concerned, this method has the disadvantages of wasting time and energy, and the applications of this method are limited; （iii） the precision and stability of VFC calculated using the grid and node method are superior to those of visual estimation and supervised classification and inferior to those of visual interpretation, but, as for visual interpretation and supervised classification, gridding measurements are difficult to apply in practice because they are not time efficient; and （iv） in terms of the precision of calculation of the VFC, an information-extracting model based on an intensity, hue, saturation （IHS） color space-multi-component series segmentation strategy is s

关键词： color space transformation digital camera field measurement grassland vegetationfractional coverage.

Determination of Some Heavy-metal-ions Using a Sulfur Ion Modified BZ Oscillating System

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Chinese Chemical Letters 2006年第9期17卷 1221-1224页

作者： hua chen Wu yang Hong Xia DAI Xiao Xia WEI Jie QU Jin Zhang GAO College of Chemistry ＆ Chemical Engineering Northwest Normal University Lanzhou 730070

A highly sensitive method is developed for the determination of trace amounts of some heavy metal ions in aqueous solution based on the classical Belousov-Zhabotinskii （BZ） oscillating chemical system. Introducing of S^2- ion makes the new oscillating system Ce（SO4）2 - KBrO3 - CH2（COOH）2 - Na2S - H2SO4 have to a high sensitivity for some heavy metal ions such as Ag^＋, Pb^2＋, Hg^2＋, Cd^2＋, Cu^2＋and Bi^3＋ with detection limits down to 10^-12 mol·L^- 1

关键词： BZ oscillating system kinetic determination heavy-metal-ion sulfur ion.

Treatment efficacy of radiof requency ablation of 338 patients with hepatic malignant tumor and the relevant complications

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World Journal of Gastroenterology 2005年第40期11卷 6395-6401页

作者： Min-hua chen Wei yang Kun Yan Wen Gao Ying Dai Yan-Bin Wang Xiao-Peng Zhang Shan-Shan Yin Departmentof Ultrasound Peking University School of Oncology 52 Fu-cheng Rd Haidian District Beijing 100036 China

AIM： To investigate the treatment efficacy of radiofrequency ablation （RFA） of hepatic malignant tumor and the relevant complications. METHODS： A total of 338 patients with 763 hepatic tumors underwent ultrasound-guided RFA （565 procedures）. There were 204 cases of hepatic cellular carcinoma （HCC） with 430 tumors, the mean largest diameter was 4.0 cm. Of them, 48 patients （23.5%） were in stages Ⅰ-Ⅱ （UICC Systems） and 156 （76.5%） in stages Ⅲ-Ⅳ There were 134 cases of metastatic liver carcinoma （MLC）, with 333 metastases in the liver, the mean diameter was 4.1 cm, the liver metastases of 96 patients （71.6%） came from gastrointestinal tract. Ninety-three percent of the 338 patients were treated using the relatively standard protocol. Crucial attention must be paid to monitor the abnormal changes in ultrasound images as well as the vital signs of the patients to find the possible hemorrhage and peripheral structures injury in time. The tumors were considered as ablated completely, if no viability was found on enhanced CT within 24 h or at 1 mo after RFA. These patients were followed up for 3-57 too. RESULTS： The ablation success rate was 93.3% （401/430 tumors） for HCC and was 96.7% （322/333 tumors） for MLC. The local recurrence rate for HCC and MLC was 7.9% （34/430 tumors） and 10.5% （351333 tumors）, respectively. A total of 137 patients （40.5%） underwent 2-11 times of repeated ablations because of tumor recurrence or metastasis. The 1st, 2nd, and 3rd year survival rate was 84.6%, 66.6%, and 63.1%, respectively; the survival rate from 48 patients of I-II stage HCC was 93.7%, 80.4%, and 80.4%, respectively. The major complication rate in this study was 2.5% （14 of 565 procedures）, which consisted of 5 hemorrhages, i colon perforation, 5 injuries of adjacent structures, 2 bile leakages, and 1 skin burn. CONCLUSION： RFA, as a minimally invasive local treatment, has become an effective and relatively safe alternativefor the patients of hepatic malignant tumor, even of advanc

关键词： Radiofrequency ablation Liver neoplasms Survival Complication Ultrasonography

Characteristic Optimization of 1.3 μm High-Speed MQW InGaAsP-AIGaInAs Lasers

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Chinese Physics Letters 2012年第6期29卷 141-144页

作者： MAO Yi-Wei WANG Yao chen yang-hua XUE Zheng-Qun LIN Qi DUAN Yan-Min SU Hui Fujian Institute Of Research on the Structure of Matter Chinese Academy of SciencesFuzhou 350002

We investigate 1.3μm multi quantum-well (MQW) lasers with InGaAsP (well) and InGaAIAs (barrier) on InP for high speed application,compared to the typical structures of In GaAsP (well)-InGaAsP (barrier)/InP and InGaAlAs (well)-InGaAlAs (barrier)/InP with the same quaternary in the well and *** calculate the characteristics of band offset and gain of InGaAsP-AlGaInAs quantum wells ( Q Ws).The advances of the new Q W design are mainly rooted in the large ratio between conduction-band and valence-band offsets (△Ec:△Ev =7:1),higher than the typical value of 4:6 in InGaAsP-InGaAsP and 7:3 in InGaAlAs-InGaAlAs for 1.3μm *** to the 1ow confinement energy of holes,non-uniformity of carrier distribution over multi-InGaAsP-AlGaInAs QWs is significantly *** enhancement of high-speed performance of InGaAsP-AlGaInAs MQW lasers is investigated in terms of turn-on oscillation.

关键词： InGaAsP GaAsP barrier

High mechanical index post-contrast ultrasonography improves tissue structural display of hepatocellular carcinoma

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Chinese Medical Journal 2005年第24期118卷 2046-2051页

作者： chen Min-hua yang Wei DAI Ying WU Wei Department of Ultrasound Peking University School of OncologyBeijing 100036 China

Background The advent of second generation agent-SonoVue and low mechanical index real-time contrast enhanced ultrasonography （CEUS） imaging have been shown to improve the diagnostic performance of uhrasonography in hepatocellular carcinoma （HCC）. But no report has described the effect of high mechanical index （MI） post-CEUS. This study aimed to investigate the value of post-CEUS in displaying tissue structures of HCC. Methods Seventy-six HCCs in 65 patients were included in the study. Each patient underwent three scans, high-MI （ MI ： 0. 15 - 1.6 ） pre-contrast ultrasound, low-MI （ MI ： 0. 04 - 0. 08 ） CEUS with contrast agent SonoVue, and high-MI post-contrast ultrasound, which was performed within 3 minutes after CEUS. The size, boundary, echogenicity, internal echotexture and posterior acoustic enhancement of the HCCs in the conventional scans before and after CEUS were evaluated. According to pathological evidence, diagnosis rates of pre-contrast, CEUS and post-contrast scans were determined and compared. The potential mechanism of post-contrast ultrasound imaging was also discussed. Results Compared with pre-contrast, post-contrast ultrasound showed improvement in image quality in most HCCs： twenty-six （34. 2% ） more lesions showed well defined margins and fourteen （18.4%） more nodules showed halo sign; twenty-three （30. 3% ） lesions demonstrated enlarged in sizes; changes in echogenicity were seen in 30 lesions （39.5%） ; eighteen （23.7%） more lesions showed heterogenecity and 20 （26. 3% ） more lesions showed “mosaic”or “nodule-in-nodule” sign; twelve （15.8%） more lesions showed posterior acoustic enhancement. Post-contrast ultrasound showed increased diagnostic accuracy of 93.4% （71/76）, compare with 88.2% （67/76） of CEUS alone. Conclusions High-MI post-contrast ultrasound utilizes harmonic signals during the rupture of microbubbles, and significantly improves the display of echo-characteristics of HCCs in ultrasound images, which adds diagnostic values

关键词： ultrasonography contrast enhanced ultrasound liver neoplasm tissue structure

lncRNA SNHG4 enhanced gastric cancer progression by modulating miR-409-3p/CREB1 axis

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Oncology Research 2025年第1期33卷 185-198页

作者： ZHOUyang chenG YUchen hua yang CAO JUN QIN Department of General Surgery Affiliated Hospital of Nantong UniversityNantong226001China Department of Surgery Affiliated Hospital of Nantong UniversityMedical School of Nantong UniversityNantong226001China Department of Operation Affiliated Hospital of Nantong UniversityNantong226001China

Objective:Gastric cancer(GC)is a globally common cancer characterized by high incidence and mortality *** in the molecular understanding of GC provide promising targets for GC diagnosis and *** non-coding RNAs(lncRNAs)and their downstream regulators are regarded to be implicated in the progression of multiple types of *** have shown that the lncRNA small nucleolar RNA host gene 4(SNHG4)serves as a tumor promoter in various malignancies,while its function in GC has yet to be ***,our study aimed to explore the role and underlying mechanism of SNHG4 in ***:We used qRT-PCR to analyze SNHG4 expression in GC tissues and ***-Meier analysis was used to assess the correlation between SNHG4 expression and the survival rate of GC *** function experiments such as CCK-8,BrdU,colony formation,flow cytometry analysis,and transwell were performed to explore the effects of SNHG4 on GC cell proliferation,apoptosis,cell cycle,migration,and *** also established xenograft mouse models to explore the effect of SNHG4 on GC tumor ***,dual luciferase reporter assay was used to verify the interaction between SNHG4 and miR-409-3p and between miR-409-3p and cAMP responsive element binding protein 1(CREB1).Results:The results indicated that SNHG4 was overexpressed in GC tissues and cell lines,and was linked with poor survival rate of GC ***4 promoted GC cell proliferation,migration,and invasion while inhibiting cell apoptosis and cell cycle arrest in *** in vivo experiment indicated that SNHG4 facilitated GC tumor ***,SNHG4 was demonstrated to bind to ***,CREB1 was directly targeted by *** assays demonstrated that miR-409-3p deficiency reversed the suppressive impact of SNHG4 knockdown on GC cell ***,miR-409-3p was also revealed to inhibit GC cell proliferation,migration,and invasion by targeting CREB1

关键词： Gastric cancer Small nucleolar RNA host gene 4(SNHG4) MicroRNA-409-3p(miR-409-3p) cAMP responsive element binding protein 1(CREB1)

Rapid and scalable preparation of highly quaternized polymer networks to achieve efficient simultaneous adsorption of iodide and pertechnetate

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Science China Chemistry 2025年第1期68卷 337-349页

作者： Meiyun Xu Song Gu Fulong chen Zhe Zhao Peng Liu Daoben hua State Key Laboratory of Radiation Medicine and Protection School of Radiological and Interdisciplinary Sciences (RAD-X) Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions Soochow University

The efficient separation of fission products,such as TcO4-and I-,holds strategic significance for the management of radioactive wastes and environmental *** this study,we propose an ultrafast strategy for scalable preparation of a highly quaternized organic network to facilitate efficient and synchronous separation of iodide and *** network can be prepared within a few minutes at room temperature,using polyethylenimine and 1,2,4,5-tetrakis（bromomethyl）benzene as building *** chlorine replacement,the network,abundantly decorated with quaternary ammonium groups （Cl@QPN）,exhibits an ultrahigh positive charge density of 7.6 mmol/*** enables the rapid and efficient enrichment of target anions through strong electrostatic Coulomb *** a result,Cl@QPN exhibits significantly higher adsorption rate constants of 0.830 g/（mg min） for ReO4-（a nonradioactive surrogate of TcO4-） and 0.677 g/（mg min） for I-compared to other ***,it possesses high adsorption capacities,reaching 1,681 mg/g for ReO4-and 917.4 mg/g for I-.Cl@QPN also demonstrates good selectivity towards target ions and shows efficient adsorption for99TcO4-.Additionally,Cl@QPN exhibits high dynamic processing capacities,handling up to 3,100 and 7,400 kg of simulated streams per kilogram of material for I-and ReO4-,respectively.

关键词： quaternized polymer networks adsorption pertechnetate iodide liquid radioactive streams

Surgical staged treatment for moderate to severe adolescent cervical kyphosis

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Chinese Medical Journal 2011年第23期124卷 3864-3867页

作者： LIANG Lei ZHOU Xu-hui LIU yang GAO Rui chen hua-jiang yang Li-li SHI Sheng YUAN Wen Department of Spine Surgery Changzheng Orthopaedics Hospital the Second Military Medical University Shanghai 200003 China

Adolescent cervical kyphosis refers to manifestation characterized by loss of physiological cervical lordosis with involvement of multiple cervical vertebrae. There is no standard treatment strategy for this disease, especially in those patients who need surgical intervention. The aim of this study was to evaluate the surgical staged treatment for moderate to severe adolescents cervical kyphosis. Methods A total of 26 adolescent with cervical kyphosis were retrospectively assigned into following two groups according to the magnitude of kyphosis： moderate group （n=17）, the Cobb angle was 46.6°±4.8°. The surgical procedure was that skull traction was first carried out for 5-7 days and then the anterior fusion and instrumentation were performed. Severe group （n=-9）, the Cobb angle was 61.6°±4.8°. The treatment strategy was that the anterior release were first performed, followed by skull traction for 7-10 days, and then anterior fusion were performed. Radiographic evaluation was performed postoperatively. Results Three days after surgery, the X-ray examination showed that the Cobb angle was -8.9°±6.8° in the moderate group and -6.0°±6.3° in the severe group. The deformed appearance was obviously corrected, with neck pain and neurologic function improved significantly. Further magnetic resonance imaging （MRI） indicated the physiology curvature of the cervical spine had been reconstructed. Conclusion Surgical staged treatment may be an ideal therapeutic intervention for cervical kyphosis patients with a Cobb angle exceeding 35° in adolescents.

关键词： cervical vertebrae kyphosis staged treatment adolescent