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NuMED CHEATHAM-PLATINUM STENT AND BALLOON IN BALLOON DELIVERY CATHETER FOR TREATMENT OF NATIVE COARCTATION OF THE AORTA

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Chinese Medical Sciences Journal 2006年第1期21卷 65-67页

作者： Guang-yi wang Bo Yang zhi-feng wang Jun Guo Lu-yue Gai Guang zhi Department of Cardiology General Hospital of People＇s Liberation Army Beijing 100853

COARCTATION of the aorta (CoA) is a congenital heart defect involving a narrowing of the *** narrowed segment called coarctation is most likely to happen in the segment just after the aortic *** narrowing can be removed by surgery or sometimes by a nonsurgical balloon ***, aortic coarctation may recur even after successful surgery or balloon ***, coarctation can now be treated with nonsurgical balloon dilation associated with implanting a stent using cardiac *** we reported our experience in a 19-year-old boy with CoA who underwent successful covered Cheatham-Platinum (CP) stent implantation for the coarctation.

关键词： covered stent coarctation of the aorta catheter intervention

Effect of tramadol on immune responses and nociceptive thresholds in a rat model of incisional pain

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第11期9卷 895-902页

作者： Yong-min LIU Sheng-mei ZHU Kui-rong wang zhi-ying feng Qing-lian CHEN Department of Anesthesiology the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China

Objective： To evaluate the effects oftramadol on the proinflammatory responses in a rat model of incisional pain by investigating its effects on nociceptive thresholds and serum interleukin-6 （IL-6） and IL-2 levels. Methods： Forty-two male Sprague-Dawley （SD） rats scheduled for plantar incision were randomly divided into 7 groups 01=6 in each group）. Rats in Group 1 receiving general anesthesia with no incision were served as control; At 30 min before skin incision, Groups 2-5 were given 5 ml normal saline or 1, 10, and 20 mg/kg tramadol, respectively, intraperitoneally （i.p.）; Group 6 received 10 mg/kg tramadol after operation; Group 7 received 10 mg/kg tramadol before incision, followed by 200 μg/kg naloxone after operation. Mechanical allodynia was measured by electronic yon Frey filament to evaluate the nociceptive thresholds 1 h before incision, and 1 h and 2 h after operation. Serum IL-6 and IL-2 levels were measured by enzyme-linked immunosorbent assay （ELISA） 2 h after operation. Results： Mechanical thresholds decreased significantly and serum IL-6 level increased significantly after operation in Group 2 compared with control （P〈0.01）, and these changes were reversed respectively by tramadol in a dose-dependent manner （P〈0.05 and P〈0.01, respectively）. IL-2 level remained unchanged after operation in Group 2, but decreased in Group 3 （P〈0.05）, then gradually returned to the normal level in Groups 4 and 5. The intraperitoneally injected tramadol （10 and 20 mg/kg） produced a potent and dose-dependent antinocicptive effect on the lesioned paw. The antinocicptive effects of tramadol were partially an- tagonized by naloxone （200 μg/kg）, suggesting an additional non-opioid mechanism. Conclusion： The results suggest that tramadol could be a good choice for the treatment of pain under the conditions that immunosuppression may be particularly contraindicated.

关键词： Tramadol Pain Mechanical allodynia lnterleukin-6 (IL-6) Interleukin-2 (IL-2) Rat

Molecular Structures and Catalytical Performance in Suzuki-coupling Reaction of Novel Dipalladium Clip-shaped Complexes with Bifunctional Pyrazolate Ligands

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Chinese Journal of Structural Chemistry 2021年第7期40卷 843-850,837页

作者： HU Xiao-Peng wang zhi-feng DENG Wei TONG Jin YU Shu-Yan Laboratory fdr Self-assembly Chemistry Center of Excellence for Environmental Safety and Biological EffectsBeijing Key Laboratory for Green Catalysis and SeparationDepartment of Environment and LifeBeijing University of TechnologyBeijing 100124China

A series of clip-shaped cationic molecular corners C1~C4(C1=[(bpy)_(2)Pd_(2)(L^(1))_(2)]^(2+),C2=[(dmbpy)_(2)Pd_(2)(L^(1))_(2)]^(2+),C3=(bpy)_(2)Pd_(2)(L^(2))_(2)]^(2+),C4=(dmbpy)_(2)Pd_(2)(L^(2))_(2)]^(2+),bpy=2,2-bipyridine,dmbpy=4,4΄-dimethyl-2,2-bipyridine)were synthesized through dipalladium complexes[(bpy)_(2)Pd_(2)(NO_(3))_(2)](NO_(3))_(2),[(dmbpy)_(2)Pd_(2)(NO_(3))_(2)](NO_(3))_(2)and bifunctional pyrazole ligands 4-(3,4-dimethoxyphenyl)-3,5-dimethyl-1H-pyrazol(HL^(1))and 4,4΄-(5-(^(1)H-pyrazol-4-yl)-1,3-phenylene)dipyridine(HL^(2)).Complexes C1~C4 were characterized by^(1)H and^(13)C NMR,electrospray ionization mass spectrometry(ESI-MS),elemental analysis,and IR *** X-ray diffraction analysis of C1∙2NO_(3)−revealed a Pd_(2)dimetallic clip-shaped structure which was synthesized by two bifunctional ligands doubly bridged by the[(bpy)Pd]_(2)dimetal ***,all of the complexes with NO_(3)−as counter anions exhibited high-efficiency catalytical performance in the Suzuki-coupling reaction attributed to the tunable impact and weak dinuclear Pd(Ⅱ)···Pd(Ⅱ)intramolecular bonding interaction.

关键词： dipalladium supra molecules bifunctional pyrazolate ligands catalysis Suzuki-coupling reaction

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Influence of different post core materials on the color of Empress 2 full ceramic crowns

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Chinese Medical Journal 2006年第20期119卷 1715-1720页

作者： GE Jing wang Xin-zhi feng Hai-lan Department of Prosthodontics School and Hospital of StomatologyPeking University Beijing 100081 China

Background For esthetic consideration, dentin color post core materials were normally used for all-ceramic crown restorations. However, in some cases, clinicians have to consider combining a full ceramic crown with a metal post core. Therefore, this experiment was conducted to test the esthetical possibility of applying cast metal post core in a full ceramic crown restoration.Methods The color of full ceramic crowns on gold and Nickel-Chrome post cores was compared with the color of the same crowns on tooth colored post cores. Different try-in pastes were used to imitate the influence of a composite cementation on the color of different restorative combinations. The majority of patients could not detect any color difference less than △E 1.8 between the two ceramic samples. So, △E 1.8 was taken as the objective evaluative criterion for the evaluation of color matching and patients＇ satisfaction. Results When the Empress 2 crown was combined with the gold alloy post core, the color of the resulting material was similar to that of a glass fiber reinforced resin post core （△E = 0.3）. The gold alloy post core and the try-in paste did not show a perceptible color change in the full ceramic crowns, which indicated that the color of the crowns might not be susceptible to change between lab and clinic as well as during the process of composite cementation. Without an opaque covering the Ni-Cr post core would cause an unacceptable color effect on the crown （△E = 2.0）, but with opaque covering, the color effect became more clinically satisfactory （△E = 1.8）. Conclusions It may be possible to apply a gold alloy post core in the Empress 2 full ceramic crown restoration when necessary. If a non-extractible Ni-Cr post core exists in the root canal, it might be possible to restore the tooth with an Empress 2 crown after covering the labial surface of the core with one layer of opaque resin cement.

关键词： color difference ceramic crown post core try-in paste

Preliminary experience using transthoracic echocardiography guiding percutaneous closure of ruptured right sinus of Valsalva aneurysm

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Chinese Medical Journal 2011年第10期124卷 1477-1482页

作者： LI Yue wang Guang-yi wang zhi-feng GUO Liang Department of Ultrasound Chinese People's Liberation Army General Hospital Beijing 100853 China Department of Cardiology Chinese People's Liberation Army General Hospital Beijing 100853 China

Background In the 21st century, minimally invasive treatment is one of the main developmental directions of medical sciences. It is well known that the echocardiography plays an important role during interventional treatments of some structural heart diseases. Because the ruptured right sinus of the Valsalva aneurysm （RRSVA） is a rare disease, there were few reports about percutaneous catheter closure of RRSVA. This study aimed to sum up our experience with transthoracic echocardiography （TTE） during percutaneous catheter closure of *** Five RRSVA cases were treated with percutaneous catheter closure. The whole procedure was guided and monitored by TTE and fluoroscopy. The maximum diameter of the RRSVA was measured by TTE before and after the catheter passed through the rupture site. A duct occluder 2 mm larger than the maximum diameter was chosen. The closure effects were evaluated with TTE and fluoroscopy immediately after the occluding device was deployed. All patients were followed up by TTE for 8 to 30 *** Before the catheter passed through the rupture site the maximum diameter of the RRSVA measured with TTE and aortography were （7.9 ±2.1） mm and （7.8 ± 1.8） mm. After the catheter passed through the rupture site the maximum diameter measured with TTE was （11.2 ± 3.2） mm, which was significantly larger than before the procedure （P 〈0.05）. The percutaneous catheter closure was successful in four cases and failed in one. Compared to the aortography the TTE was better at distinguishing residual shunts from aortic valve regurgitation immediately after the occluding device was deployed. There were no complications during 8 to 30 months of *** Transthoracic echocardiography can play an important role during percutaneous catheter closure of RRSVA,especially for estimating the size of the RRSVA after the catheter passes through the rupture site, and differentiating residual shunt from aortic valve regurgitation immediately after the

关键词： transthoracic echocardiography ruptured aneurysm of sinus percutaneous catheter closure

A HIGH-ORDER-ACCURATE DIFFERENCE SCHEME WITH UNCONDITIONAL STABILITY FOR THE DIFFUSION EQUATION ON NONUNIFORM GRIDS

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Journal of Hydrodynamics 2001年第1期13卷 92-98页

作者： wang Xuan, Yang zhi-feng State Key Laboratory of Environment Simulation and Pollution Control, Institute of Environmental Sciences, Beijing Normal University, Beijing 100875, China[WT5”HZ] Beijing Normal Univ. Beijing 100875 China

WT5”BZ]A high-order-accurate difference scheme with unconditional stability is developed for the diffusion equation on nonuniform grids. The theoretical analysis shows that the accuracy of this scheme is between third order and fourth order, and fourth-order accuracy is achieved in the case of the same grid steps being used within the computational domain. Two numerical examples are given to demonst ate the advantages of the proposed scheme. Compared with the conventional difference scheme, more accurate numerical solution can be obtained by using the proposed scheme even with relatively larger grid sizes. It is also pointed out that the appropriate structure of the nonuniform grid can not only make the proposed scheme more practical, but lead to a solution superior to that for a uniform grid structure. [WT5”HZ]

关键词： ]finite difference scheme diffusion equation nonuniform grid high accuracy computational fluid dynamics

Microstructural evolution during tempering process and mechanical properties of Cr-Ni-Mo-V/Nb high strength steel

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Journal of Iron and Steel Research International 2025年第1期32卷 270-281页

作者： Zi-wei Lv Jing Fan Rui wang zhi-qiang Yu Yan Kang Yong Hu Lei-feng Tuo Jürgen Eckert zhi-jie Yan School of Materials Science and Engineering North University of ChinaTaiyuan 030051ShanxiChina Shanxi Key Laboratory of Advanced Metal Materials for Special Environments North University of ChinaTaiyuan 030051ShanxiChina School of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan 030024ShanxiChina Erich Schmid Institute of Materials Science Austrian Academy of SciencesLeoben 8700Austria Department of Materials Science Chair of Materials PhysicsMontanuniversitat LeobenLeoben 8700Austria

High strength steels exhibit superior mechanical properties due to the unique microstructure,which successfully solves the drawback of the inevitable strength-toughness trade-off that occurs in traditional *** we investigated the effect of matrix and precipitates on mechanical properties of Cr-Ni-Mo-V/Nb steel after water quenching and tempering(150-500℃).The results showed that the microstructure of the present steel is noticeably tuned by changing the tempering *** excellent combination of strength(a yield strength of 1308 MPa with a total elongation of 8.2%)and toughness(Charpy V-notch impact toughness of 40.5 J/cm^(2))is obtained upon tempering at 200℃.This is attributed to the lath martensite containing high dislocation density,the martensite-twin substructure,and the strengthening effects of the precipitated needle-likeε-carbides and spherical VC *** acicularε-carbides are replaced by the rod-shaped Fe_(3)C at the tempering temperature of 350℃,resulting in the remarkable deterioration in strength,hardness,and *** carbides formed at a tempering temperature of 500℃ are beneficial to the enhancement of the elongation and toughness,but the strength decreases due to the matrix softening caused by the recovery of dislocation.

关键词： High strength steel Tempering Microstructure Carbide Mechanical property

Dramatic Changes of Matrix Metalloproteinases-7 and Lysozyme in the Ulcerative Colitis of Mice Induced by Dextran Sulfate Sodium

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Journal of Integrative Agriculture 2014年第4期13卷 858-869页

作者： KANG Jing-jing ZHAO De-ming TENG Ke-dao JIAO Xi-lan wang Ping-li SUN Zhe NI Pei-pei wang zhi-feng ZHANG Rui YANG Yu-rong LIANG Hong-de Pathology Laboratory College of Animal Husbandry and Veterinary Science Henan Agricultural University College of Animal Medicine China Agricultural University

Ulcerative colitis （UC） is a lifelong illness with profound emotional and social impacts, and could cause serious damage to large intestine, especially in colon. However, the pathogenesis of UC remained unclear. The present study attempts to find out the role of matrix metalloproteinases-7 （MMP-7） and lysozyme in the pathogenesis of UC through a mice model induced by dextran sulfate sodium （DSS）. The UC model was evaluated both by disease activity index （DAI） and the intestinal histopathology. The results show that there is a high correlation between the DAI score and the pathological changes of colon. Interleukin-6 （IL-6） serum levels and large intestinal fluids levels in UC mice are always higher than that of the control groups, which might be associated with the degree of the inflammation damage in the colon. The change tendency of the MMP-7 mRNA and protein expressions are both up-regulated firstly and then down-regulated from 1 to 5 d in the colon, but only the MMP-7 protein is up-regulated at 7 d again. The up-regulated MMP-7 levels in the early stage of UC may play a protective role through the activated defensins, while the down-regulated levels in the mid-later stage of UC may be connected with the severe lesions in the colon. However, the up-regulated MMP-7 levels in the later stage of UC in the colon may also contribute to the tissue repair or be served as a marker to CRC （colorectal cancer）. The distribution of lysozyme protein indicates that there may be Paneth-like cells in the colon. Both the changes of MMP-7 and lysozyme in the small intestine may play a protective role for the safe environment of the whole gut, especially to the colon of UC.

关键词： matrix metalloproteinases-7 lysozyme interleukin-6 ulcerative colitis dextran sulfate sodium

The mechanisms of pH regulation on promoting volatile fatty acids production from kitchen waste

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Journal of Environmental Sciences 2025年第1期147卷 414-423页

作者： feng Liu Tingting wang Leiyu feng Yinguang Chen College of Environmental Science and Engineering Tongji UniversityShanghai 200092China TUS-Environmental Science and Technology Development Co. Ltd.Beijing 100084China

The anaerobic acid production experiments were conducted with the pretreated kitchen waste under pH *** results showed that pH 8 was considered to be the most suitable condition for acid production,especially for the formation of acetic acid and propionic *** average value of total volatile fatty acid at pH 8 was 8814 mg COD/L,1.5 times of that under blank *** average yield of acetic acid and propionic acid was 3302 mg COD/L and 2891 mg COD/L,*** activities of key functional enzymes such as phosphotransacetylase,acetokinase,oxaloacetate transcarboxylase and succinylcoA transferase were all *** further explore the regulatory mechanisms within the system,the distribution of microorganisms at different levels in the fermentation system was obtained by microbial sequencing,results indicating that the relative abundances of Clostridiales,Bacteroidales,Chloroflexi,Clostridium,Bacteroidetes and Propionibacteriales,which were great contributors for the hydrolysis and acidification,increased rapidly at pH 8 compared with the blank ***,the proportion of genes encoding key enzymes was generally increased,which further verified the mechanism of hydrolytic acidification and acetic acid production of organic matter under pH regulation.

关键词： Kitchen waste Acid fermentation Volatile fatty acids pH regulation Functional genes