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World Journal of Mechanics 2018年第4期8卷 73-81页

作者： Mohamed s.El Naschie Department of Physics Faculty of ScienceUniversity of AlexandriaAlexandriaEgypt

The paper starts from the remarkable classical equation of the great nineteenth century Russian physicist Nikolay Umov E=kmc2 where 1/2≤k≤1, m is the mass, c is the speed of light and E is the equivalent energy of m. After a short but deep discussion of the derivation of Umov we move to Einstein’s formula E=γmc2?where γis the Lorentz factor of special relativity and point out the interesting difference and similarity between Umov’s k and Lorentz-Einstein γ. This is particularly considered in depth for the special case which leads to the famous equation?E=mc2?that is interpreted here to be the maximal cosmic energy density possible. subsequently we discuss the dissection of E=mc2 into two components, namely the cosmic dark energy density E(D)=(21/22)MC2 and the ordinary energy density E(O)=MC2/22? where?E(D)+E(O)=MC2. Finally we move from this to the three-part dissection where we show that E is simply the sum of pure dark energy E(PD) plus dark matter energy E(DM) as well as ordinary energy E(O).

关键词： N.Umov Energy A.Einstein Energy El Naschie Energy Ordinary Cosmic Energy Cosmic Dark Energy F.Hasenohrl’s Electromagnetic Energy H.Poincaré History of special Relativity

Highly efficient synthesis of β-amino esters via Mannich-type reaction under solvent-free conditions using ZnCl_2 catalyst

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Chinese Chemical Letters 2009年第4期20卷 407-410页

作者： albert s.C.Chan school of Pharmaceutical science Sun Yat-Sen University

β-Amino esters were synthesized via ZnCl2-catalyzed Mannich-type reaction of imines and malonate esters under solvent-free conditions in 6 min. The β-amino ester was converted into the corresponding aspartic acid de... 详细信息

关键词： β-Amino esters Aspartic acid derivativates Mannich-type reaction solvent-free Krapcho decarboxylation reaction Zinc chloride

Extracorporeal liver support in severe alcoholic hepatitis

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World Journal of Gastroenterology 2014年第25期20卷 8011-8017页

作者： albert Parés Antoni Mas Liver Unit Hospital ClínicUniversity of BarcelonaIDIBAPSCIBERehd08036 BarcelonaSpain

The severity of alcoholic hepatitis(AH) which may coexist with cirrhosis varies greatly, from asymptomatic forms which are detected in alcoholic patients without any sign of liver disease, except laboratory abnormalities, to severe forms characterised by deep jaundice, ascites, hepatic encephalopathy and low prothrombin index. In hospitalized patients the mortality could be as high as 75%. The elevated number of therapeutic proposals reported for more than forty years reveals the lack of efficacy of a particular modality. Even in the most favorable trials, the survival is already very poor and in some cases related to the development of renal failure or hepatorenal syndrome. There are some motivating reports concerning albumin dialysis as a support treatment in patients with severe AH, either alone or in combination with other pharmacological therapies. The favorable effects of albumin dialysis in patients with severe AH suggest that the procedure used alone or in combination with other therapies may have a role in this clinical condition. This will be particularly relevant to offer an alternative therapy in these patients, thus being a potential bridge to recovery or to be listed for liver transplantation.

关键词： Acute alcoholic hepatitis Alcoholic liver disease Extracorporeal liver support Molecular Adsorbents Recirculating system Hepatorenal syndrome Treatment of alcoholic hepatitis

Quality and readability of online information resources on insomnia

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Frontiers of Medicine 2017年第3期11卷 423-431页

作者： Yan Ma albert C. Yang Ying Duan Ming Dong albert s. Yeung Division of Interdisciplinary Medicine and Biotechnology Department of Medicine Beth Israel Deaconess Medical Center Harvard Medical School Boston MA 02215 USA sleep Medicine Center Airforee General Hospital Beijing 100142 China IBM Software Development Lab Littleton MA 01460 USA Depression Clinical and Research Program Massachusetts General Hospital Harvard Medical School Boston MA 02114 USA

The internet is a major source for health information. An increasing number of people, including patients with insomnia, search for remedies online; however, little is known about the quality of such information. This study aimed to evaluate the quality and readability of insomnia-related online information. Google was used as the search engine, and the top websites on insomnia that met the inclusion criteria were evaluated for quality and readability. The analyzed websites belonged to nonprofit, commercial, or academic organizations and institutions such as hospitals and universities. Insomnia-related websites typically included definitions （85%）, causes and risk factors （100%）, symptoms （95%）, and treatment options （90%）. Cognitive behavioral therapy for insomnia （CBT-I） was the most commonly recommended approach for insomnia treatment, and sleep drugs are frequently mentioned. The overall quality of the websites on insomnia is moderate, but all the content exceeded the recommended reading ease levels. Concerns that must be addressed to increase the quality and trustworthiness of online health information include sharing metadata, such as authorship, time of creation and last update, and conflicts of interest; providing evidence for reliability; and increasing the readability for a layman audience.

关键词： insomnia intemet readability information quality health literacy cognitive behavioral therapy treatment

BRITTON CHANCE IN MEMORIAM

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Journal of Innovative Optical Health sciences 2011年第3期4卷 221-222页

作者： albert s.MILDVAN The Johns Hopkins University school of Medicine 725 N.Wolfe Street Room 511 HunterianBaltimoreMD 21205USA

Britton Chance was a truly inspiring scientist,among the *** long and vigorous career in biochemistry,biophysics,and biological instrumentation began with his now-classic kinetic and spectroscopic studies of the mecha... 详细信息

关键词： Enzyme-substrate intermediates electron transport oxidative phosphorylation proton gradient electron tunneling near-infrared imaging glyoxalase I methemoproteins

Hepatotoxicity associated with glucosamine and chondroitin sulfate in patients with chronic liver disease

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World Journal of Gastroenterology 2013年第32期19卷 5381-5384页

作者： Cristian Cerda Miguel Bruguera albert Parés Liver Unit Institute of Digestive and Metabolic DiseasesHospital Clínic Department of Medicine University of Barcelona

Glucosamine and chondroitin sulfate are molecules involved in the formation of articular cartilage and are frequently used for symptom relief in patients with *** molecules are well tolerated with scarce secondary *** few cases of possible hepatotoxicity due to these substances have been *** aim of this paper is to report the frequency of presumed glucosamine hepatotoxicity in patients with liver disease.A questionnaire was given to 151 consecutive patients with chronic liver disease of different etiology(mean age 59 years,56.9%women)attended in an outpatient clinic with the aim of evaluating the frequency of consumption of these drugs and determine whether their use coincided with a worsening in liver function test ***-three patients(15.2%)recognized having taken products containing glucosamine or chondroitin sulfate previously or at the time of the *** of the clinical records and liver function tests identified 2 patients presenting an elevation in aminotransferase values temporarily associated with glucosamine treatment;one of the cases simultaneously presented a skin rash attributed to the *** of these two patients and the cases described in the literature suggest toxicity of glucosamine and chondroitin *** clinical spectrum is variable,and the mechanism of toxicity is not clear but may involve reactions of *** consumption of products containing glucosamine and/or chondroitin sulfate is frequent among patients with chronic liver diseases and should be taken into account on the appearance of alterations in liver function tests not explained by the underlying disease.

关键词： Toxic hepatitis Hepatotoxicity Glucosamine Chondroitin sulphate Osteoarthritis

Cleavable Cys labeling directed Lys site-selective stapling and single-site modification

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science China Chemistry 2022年第7期65卷 1356-1361页

作者： Jian Li Qi-Long Hu Zhendong song albert s.C.Chan Xiao-Feng Xiong Guangdong Key Laboratory of Chiral Molecule and Drug Discovery School of Pharmaceutical SciencesSun Yat-sen UniversityGuangzhou 510006China

site-selective modification of peptide/protein is a vital approach to disclose post-translational modifications(PTMs) and plays a crucial role in chemical biology, as well as drug development. Compared with synthetic and chemical biology methods, chemical modification of native peptide/protein provides a more versatile approach to achieve late-stage diversification for functional studies. Lysine featured high nucleophilicity, frequency, and solvent accessibility, making its site-selective modification important but elusive. Herein, we reported a visible-light-driven and Cys-directed Lys site-selective stapling approach for peptide/protein. By cleavable Cys anchoring, site-selective Lys single-site modification was achieved, and this method could be applied to multi-functionalization.

关键词： lysine protein modification single-site modification stapling

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simply air:Vanadium-catalyzed oxidative kinetic resolution of methyl o-chloromandelate by ambient air

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Chinese Chemical Letters 2010年第7期21卷 774-777页

作者： Lu Yin Xian Jia Xing shu Li albert s.C. Chan school of Pharmaceutical Engineering Shenyang Pharmaceutical UniversityShenyang 110016China school of Pharmaceutical sciences Sun Yat-Sen UniversityGuangzhou 510006China

Vanadium-catalyzed oxidative kinetic resolution（OKR） of methyl o-chloromandelate 2a,key intermediate of the well-known oral antiplatelet agent（s）-clopidogrel,was achieved by ambient air for the first *** air oxidation system,which was composed of vanadium and tridentate schiff base ligands derived from amino alcohols and salicylaldehyde derivatives,afforded an efficient and economic approach to the target intermediate with high enantioselectivities（99%ee）.

关键词： Ambient air Vanadium-catalyzed OKR Methyl o-chloromandelate schiff base ligands

Characterization of Fe_3O_4/P(st-MPEO) Amphiphilic Magnetic Polymer Microspheres

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Chemical Research in Chinese Universities 2002年第4期18卷 458-461页

作者： CHAN albert s. C. YIP C. W. Open Laboratory of Chirotechnology and Department of Applied Biology and Chemical Technology Open Laboratory of Chirotechnology and Department of Applied Biology and Chemical Technology Hong Kong Polytechnic University Hong Kong P. R. ChinaHong Kong Polytechnic University Hong Kong P. R. China

Amphiphilic magnetic microspheres consisting of styrene and poly(ethylene oxide) macromonomer(MPEO) were prepared by dispersion copolymerization in the presence of Fe_3O_4 magnetic fluid in an ethanol/water medium. The sizes of the magnetic microspheres and their distribution were characterized by means of scanning electron microscopy(sEM). The surface morphology and the average surface roughness of the microspheres were investigated by virtue of atomic force microscopy(AFM). It was found that the microspheres exhibit microscopic phase-separate and the mean square surface roughness of the microspheres increases with increasing MPEO used in the copolymerization. The amphiphilic magnetic microspheres containing 0 4-3 5 mg/g hydroxyl groups could be prepared from MPEO with different concentrations and styrene.

关键词： Amphiphilic magnetic polymer Microsphere Copolymerization

Retinal vein occlusion associated with combined hormonal contraceptive vaginal ring use

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International Journal of Ophthalmology(English edition) 2018年第5期11卷 891-892页

作者： albert s.Li Jonathan Naysan Ronni M.Lieberman Department of Ophthalmology Hofstra Northwell School of MedicineNorthwell Health Department of Ophthalmology & Visual sciences Washington University School of Medicine Department of Ophthalmology Queens Hospital Center

Dear Editor,We read with interest your recent article on the impact of combined oral contraceptives on ocular *** report a case of a branch retinal vein occlusion（BRVO）associated with use of an etonogestrel/ethinyl estradiol vaginal ring（NuvaR ing）,an implantable combined hormonal contraceptive,in a young healthy female with no other identifiable risk factors.

关键词： Retinal vein occlusion hormonal contraceptive vaginal ring use