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Special Reaction and Polypeptide Analysis of Apple Rootstock Calli Under Iron Deficiency Stress

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Science China Chemistry 1994年第12期37卷 1463-1470页

作者：卞学渝李港丽苏润宇陈正华 lab No.2 of Breeding the Research Institute of ForestryChinese Academy of ForestryBeijing 100091 Department of Horticulture Beijing Agricultural UniversityBeijing 100094PRC Institute of Genetics Academia SinicaBeijing 100101PRC

The callus experiment systems derived from sterile stem segments subject to subcultures have been established for Malus baccata(L.)Borkh that is sensitive to iron deficiency stress,and for ***- cromalus Makino that is tolerant to iron deficiency *** physiological and biochemical changes under iron deficiency stress were compared between 2 species using these *** iron deficiency stress, the dry and fresh weights of *** callus increased,and the contents of elements P,S,Mg,K,Zn,B, *** too,while its ferric iron reduction capacity did not *** nltramicrostructure of cells were damaged to some degree,and only the 25-kD polypeptide was synthesized when the NaHCO_3 was added into the *** the contrary,under iron deficiency stress the dry weight of *** callus did not change,the ferric iron reduction capacity increased;the content of P and S greatly decreased;the trans- fer cells were formed;and the polypeptide of 25,34 and 100 kD were *** results show that the different reactions of *** and *** to iron deficiency conditions are determined by their different genetic *** is feasible to study iron chlorosis under tissue culture condition,and it is possible to select the best species and new varieties tolerant to iron deficiency by using in vitro culture sys- tems.

关键词： apple root stock callus iron deficiency polypeptide analysis.

Anisotropic FCGR behaviour in hot-rolled Mg-3Al-0.5Ce alloy

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Journal of Magnesium and Alloys 2024年第7期12卷 2985-3002页

作者： Prakash C.Gautam Somjeet Biswas Light Metals and Alloys Research lab Department of Metallurgical and Materials EngineeringIndian Institute of Technology KharagpurKharagpurWest Bengal 721302India Institut für Metallkunde und Materialphysik(IMM) Rheinisch-Westfälische Technische Hoschule Aachen52074 AachenGermany

In this work,anisotropic fatigue crack growth rate(FCGR)behaviour in a hot-rolled Mg-3wt%Al-0.5wt%Ce alloy was investigated using compact tension(CT)specimens with notch(an)parallel to the rolling direction(RD)and transverse direction(TD).The FCGR tests were conducted at a constant load ratio(R=0.1)and maximum stress intensity factor(KMax=15.6 MPa√m)to investigate the crack closure *** both constant R and KMax conditions:(i)the load-displacement curves for every loading cycle were linear for a_(n)∥ to RD and TD,indicating no crack closure;(ii)the FCGR was found to be lower for an∥RD than an∥TD over the entire stress intensity factor range(△K).The hot-rolled sample contained long-aligned Al11Ce3 intermetallic phase within grain boundaries that are elongated along *** the FCGR test,{10.12}extension twins(ET)with lamellae∼⊥and c-axis∼∥to these elongated intermetallics along RD developed irrespective of the notch *** the loading cycle,these intermetallics along RD generate back-stresses,reducing the in-plane tensile stress∼||and∼⊥to crack-tip to∼0 for a_(n)∥to RD and TD,***,lenticular ET∼||⊥and∼||,with c-axis∼||and∼⊥to crack path activates,leading to trans and inter lamellar crack for anto RD and TD,respectively,and anisotropic *** crack in a_(n)∥RD reduces the FCGR due to plastic energy dissipation as perceived by comparatively more geometrically necessary boundaries(GNBs).On the other hand,faster FCGR was obtained for a_(n)∥TD due to interlamellar ***,the crack growth through the matrix-ET interfaces was favoured due to strain *** Fractography for a_(n)∥RD shows smaller elongated grooves along crack propagation,which indicates crack ***,larger elongated grooves for a_(n)||TD indicated easy crack propagation due to favourable interlamellar crack.

关键词： Fatigue crack growth rate(FCGR) Magnesium(Mg) Intermetallics Extension twins Crack closure

Review of 6 Years of Middle Ear Surgery in the ENT-Laryngology Department of the Donka National Hospital and a Literature Review

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Surgical Science 2024年第8期15卷 471-479页

作者： Mamadou Aliou Diallo Ibrahima Diallo Mamadou Mouctar Ramata Diallo Sayon Kourouma Alsény Camara Alsény Cissé Abdoulaye Bayo Barry Alpha Oumar Sory Sacko Abdoulaye Keita Service dORL Hpital National Donka Conakry Guinea Service dORL Hpital Rgional de Mamou Mamou Guinea Service dORL Hpital Rgional de lab Lab Guinea

Introduction: Middle ear surgery is increasingly performed in our department. Our goal was to take stock of this activity in the ENT department of the Donka National Hospital. Equipment and Methods: It was a descriptive and retrospective study;it involved 71 patients’ records operated from January 1, 2018 to December 31, 2023. We included the files of patients who had a middle ear surgery including the post-operative report and follow-up. Incomplete or illegible records were excluded. The parameters studied were epidemiological, otoscopic, tomodensitometric, surgical indications, surgical techniques and results. Results: We recorded 71 middle ear surgeries out of 548 ENT surgeries, the prevalence was 12.96%. The average age was 23 years (type-deviation = 17, 29 years) with extremes of 3 to 75 years. According to the preoperative audiometry, the deafness was medium (48.8%), mild (36.9%) and severe (14.3%). The operative indications were among others: perforation of the tympanic sequellar (52.5%), chronic otomastoiditis (23.8%), cholesteatoma (15%) and seromuqueous otitis (8.7%). We performed 70 tympanoplasties (90.9%), 50 mastoidectomies (64.9%) and 7 trans-tympanic aerators (9.1%). One month after surgery, the neotympanum was constituted in 86%, and the hearing gain was between 11 and 15 dB in 18.3% of cases. Conclusion: Middle ear surgery was infrequent. Young subjects are the most concerned. Tympanoplasty and mastoidectomy are the main surgical techniques. The anatomical and functional results are appreciable.

关键词： Surgery Ear Tympanoplasty Mastoïdectomie

Synthesis,Structure and Hydrogenation Property of trans-PdCl_(2){Ph_(2)P[o-C_(6)H_(4)CH(OC_(2)H_(5))_(2)]}_(2)

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Chemical Research in Chinese Universities 1997年第4期13卷 117-120页

作者： Xu, PP Gao, JX Zhou, ZH Wang, JZ Chen, Z Hu, SZ Wan, HL XIAMEN UNIV DEPT CHEMSTATE KEY LAB PHYS CHEM SOLID SURFACEXIAMEN 361005PEOPLES R CHINA XIAMEN UNIV INST PHYS CHEMXIAMEN 361005PEOPLES R CHINA

Ｓｙｎｔｈｅｓｉｓ，ＳｔｒｕｃｔｕｒｅａｎｄＨｙｄｒｏｇｅｎａｔｉｏｎＰｒｏｐｅｒｔｙｏｆｔｒａｎｓ┐ＰｄＣｌ２｛Ｐｈ２Ｐ［ｏ┐Ｃ６Ｈ４ＣＨ（ＯＣ２Ｈ５）２］｝２＊ＸＵＰｉａｎ－ｐｉａｎ，ＧＡＯＪｉｎｇ－ｘｉｎｇ＊＊... 详细信息

Ｓｙｎｔｈｅｓｉｓ，ＳｔｒｕｃｔｕｒｅａｎｄＨｙｄｒｏｇｅｎａｔｉｏｎＰｒｏｐｅｒｔｙｏｆｔｒａｎｓ┐ＰｄＣｌ２｛Ｐｈ２Ｐ［ｏ┐Ｃ６Ｈ４ＣＨ（ＯＣ２Ｈ５）２］｝２＊ＸＵＰｉａｎ－ｐｉａｎ，ＧＡＯＪｉｎｇ－ｘｉｎｇ＊＊，ＺＨＯＵＺｈａｏ－ｈｕｉ，ＷＡＮ...

关键词： Palladium complex Hydrogenation Crystal structure

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用于手性药物筛分的手性功能化膜

Science China Materials 2024年第8期67卷 2532-2539页

作者：何思佳张雅倩 Sravan Baddi 赵常利窦晓秋冯传良 State Key lab of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China

将手性整合到薄膜体系中为手性分离技术的发展提供了独特的方向.然而,在膜层之间创建手性位点仍是一个有待解决的问题.在此,我们制作了一种壳聚糖/氧化石墨烯(CG)基薄膜,通过与L-色氨酸衍生物(LPWM)的非共价相互作用,CG-LPWM薄膜不仅保... 详细信息

将手性整合到薄膜体系中为手性分离技术的发展提供了独特的方向.然而,在膜层之间创建手性位点仍是一个有待解决的问题.在此,我们制作了一种壳聚糖/氧化石墨烯(CG)基薄膜,通过与L-色氨酸衍生物(LPWM)的非共价相互作用,CG-LPWM薄膜不仅保持优异的机械强度,同时具有手性功能.LPWM在薄膜中引入了手性环境,使得薄膜不仅能够视觉识别手性分子,而且对手性药物具有一定的分离性能:伪麻黄碱的光学异构体过量值超过80%.手性识别源于手性组装体与其中一种异构体具有更强或更多的氢键作用导致的优先结合.这项工作通过简单的非共价相互作用制作了手性薄膜,为手性修饰的层状膜实现对映体识别与分离指引了方向.

关键词：非共价相互作用手性分离手性识别手性分子手性药物光学异构体对映体氧化石墨烯

Endoscopic therapy for weight loss: Gastroplasty, duodenal sleeves, intragastric balloons, and aspiration

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World Journal of Gastrointestinal Endoscopy 2015年第9期7卷 847-859页

作者： Nitin Kumar Developmental Endoscopy lab Brigham and Women’s HospitalHarvard Medical School

A new paradigm in the treatment of obesity and metabolic disease is developing. The global obesity epidemic continues to expand despite the availability of diet and lifestyle counseling, pharmacologic therapy, and weight loss surgery. Endoscopic procedures have the potential to bridge the gap between medical therapy and surgery. Current primary endoscopic bariatric therapies can be classified as restrictive, bypass, spaceoccupying, or aspiration therapy. Restrictive procedures include the USGI Primary Obesity Surgery Endolumenal procedure, endoscopic sleeve gastroplasty using Apollo Over Stitch, trans Oral GAstroplasty, gastric volume reduction using the ACE stapler, and insertion of the TERIS restrictive device. Intestinal bypass has been reported using the EndoB arrier duodenal-jejunal bypass liner. A number of space-occupying devices have been studied or are in use, including intragastric balloons(Orbera, Reshape Duo, Heliosphere BAG, Obalon), transpyloric Shuttle, and Sati Sphere. The Aspire Assist aspiration system has demonstrated efficacy. Finally, endoscopic revision of gastric bypass to address weight regain has been studied using Apollo Over Stitch, the USGI Incisionless Operating Platform Revision Obesity Surgery Endolumenal procedure, Stomaphyx, and endoscopic sclerotherapy. Endoscopic therapies for weight loss are potentially reversible, repeatable, less invasive, and lower cost than various medical and surgical alternatives. Given the variety of devices under development, in clinical trials, and currently in use, patients will have multiple endoscopic options with greater efficacy than medical therapy, and with lower invasiveness and greater accessibility than surgery.

关键词： Weight loss OverStitch Aspire transoraloutlet reduction Gastric balloon Orbera EndoBarrier Apollo Primary Obesity Surgery Endolumenal Gastricbypass Duodenal sleeve Intragastric

一种新型有机染料HEASPS在不同波长时的双光子吸收和频率上转换性质研究

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光学技术 2001年第4期27卷 289-290,293页

作者：周广勇任燕王东王春方奇邵宗书蒋民华山东大学 State Key lab. of Crystal Mat. Shandong Univ. Ji'nan 250100 China

报道了一种新型双光子吸收染料 ,即反式 - 4- [4′- (N-羟乙基 - N-乙基胺基 )苯乙烯基 ]- N-甲基吡啶对甲苯磺酸盐的非线性光学性质 ;测试了染料在 72 0～ 110 0 nm波段的非线性透过率曲线。结果发现 :双光子吸收最强波长相对线性吸收... 详细信息

报道了一种新型双光子吸收染料 ,即反式 - 4- [4′- (N-羟乙基 - N-乙基胺基 )苯乙烯基 ]- N-甲基吡啶对甲苯磺酸盐的非线性光学性质 ;测试了染料在 72 0～ 110 0 nm波段的非线性透过率曲线。结果发现 :双光子吸收最强波长相对线性吸收峰波长的两倍处有明显蓝移 ;计算出的相应波长的双光子吸收截面在 930 nm处染料有最大双光子吸收截面(2 .0 6× 10 - 4 7cm4·s/ photon) ;测量了染料在 90 0～ 110 0 nm波段的上转换效率 ,在 10 2 0 nm处有最高效率 (5 .1% ) 。

关键词：双光子吸收有机染料激光上转换性质激光器

Calculation of correlation function of binary periodic sequences

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Chinese Science Bulletin 1997年第13期42卷 1065-1068页

作者： LI ChaoDepartment of System Engineering and Mathematics, National University of Defense Technology, Changsha 410073, China State Key laboratory of Mobile Communication, Southeast University, Nanjing 210018, China Dept. of Syst. Eng. and Mathematics Natl. Univ. of Defense Technology Changsha 410073 China State Key lab. of Mobile Commun. Southeast University Nanjing 210018 China

SINCE Olsen and Lempel constructed a family of optimal key sequences (called Bent se-quences) by using the trace function over finite field in 1982, the theory of trace functionhas been widely used in spread-spectrum communication and cryptology. Many papers aboutconstructing pseudorandom sequences by using trace functions were published in IEEE trans-actions on Information Theory. The sequences (such as GMW sequences, No sequences,

关键词： exponential sums quadratic forms periodic sequences correlation functions.

Research status and prospect of stem cells in the treatment of diabetes mellitus

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Science China(Life Sciences) 2013年第4期56卷 306-312页

作者： LIU XiaoFang WANG YunFang LI YaLi PEI XueTao Department of Obstetrics and Gynecology General Hospital of PLA Stem Cell and Regenerative Medicine lab Beijing Institute of Transfusion Medicine Academy of Military Medical Sciences

Beta cell mass and function are decreased to varying degrees in diabetes. Islet cell replacement or regenerative therapy may offer great therapeutic promise to people with diabetes. In addition to primary pancreatic cells, recent studies on regeneration of functional insulin producing cells (IPCs) revealed that several alternative cell sources, including embryonic stem cells, induced pluripotent stem cells and adult stem cells, can generate IPCs by differentiation, reprogramming, and trans-differentiation. In this review, we discuss stem cells as a potential alternative cell source for the treatment of diabetes.

关键词： cell therapy diabetes stem cells insulin producing cells

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