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Nabil A. Abdel-Salam

Bio: Nabil A. Abdel-Salam is an academic researcher from Alexandria University. The author has contributed to research in topics: Diterpene & Apigenin. The author has an hindex of 7, co-authored 8 publications receiving 120 citations.

Papers
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Journal ArticleDOI
TL;DR: The aerial parts of Lactuca sativa afforded lactucin, 1 11β,13-dihydrolactucin and lactupicrin, a new melampolide and 3β, 14-Dihydroxy-11β, 13-dhydrocostunolide as discussed by the authors.

39 citations

Journal ArticleDOI
TL;DR: In this article, a new acyl flavonoid apigenin-7-O-b-D-(6"-trans-p -coumaroyl)-3"-O-acetyl glucopyranoside was also isolated.
Abstract: Phytochemical study of Acanthus arboreus resulted in the isolation of three novel alkaloids: 6-hydroxy-benzoxazolinone, 4-hydroxyacanthamine and acanthaminoside. In addition, a new acyl flavonoid apigenin-7-O-b-D-(6"-trans-p -coumaroyl)-3"-O-acetyl glucopyranoside was also isolated. The known compounds were identified as apigenin, apigenin-7- O-b-D-(6"-trans-p-coumaroyl) -glucoside, vanillic acid, lupeol, stigmasterol and sitosterol glucoside. The structures were determined by physical, chemical and spectral techniques.

27 citations

Journal ArticleDOI
TL;DR: Phytochemical investigation of the alcoholic extract of the flowers of A. rosea L. led to the isolation of six flavonoids, one of which is isolated for the first time from genus Alcea and the first report for its biological investigation.

20 citations

Journal ArticleDOI
TL;DR: Aerial parts of Fagonia bruguieri afforded two new erythroxan-type diterpenes: 15,16-dihydroxy-7-oxo- cis-ent -eryTHrox-3-ene (fagonone) and 16- O -acetylfagonone, the first reported occurrence of diterPenes in the family Zygophyllaceae and the first known ent -erystroxane.

16 citations

Journal ArticleDOI
TL;DR: In this article, 8-(γ,γ-dimethyl-allyl)-1-Methoxycoumestrol has been isolated from the roots of Lotus creticus along with some known compounds.

16 citations


Cited by
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Journal ArticleDOI
17 Mar 2004-JAMA
TL;DR: The present editors have kept up-to-date and been prepared to prune the dead wood, and the book is economical in price and compact in size, but still contains the essential truths for the practice of good medicine.
Abstract: I first read Davidson 30 years ago: at that time it was already in its 5th edition. A brief comparison shows that it then contained about 440,000 words in 1,100 pages: the current edition has compressed 625,000 words into 800 pages. I think I bought it as a student because it was cheap: but also because it seemed to be comprehensive and straightforward, and I have used it as a basis for my medical knowledge ever since. So I miss some of the old pictures of the acute skin rashes such as scarlet fever: in fact infectious disease has been transferred to the back and genetic factors take the first chapters. But careful linguistic comparison will still uncover the old phrases which some of us know by heart-there are minor changes such as 'alarming reactions to intravenous iron are uncommon, but have occasionally been noted', which becomes 'alarming systemic anaphyllactic reactions can occur'. Sir Stanley Davidson made 'no attempt to describe every rare disease or syndrome, but devoted most of the space available to those disorders most commonly encountered in practice'. I have grown up with successive editions, and have gradually come to appreciate the problems of the authors in the compression of knowledge. Having got to know many of them personally as real people rather than as names I can still recommend the book. It is the essential starting point for the study of internal medicine and for many doctors will remain their base reference work. The present editors have kept up-to-date and been prepared to prune the dead wood. There are many competitors in the market, and the publishers must take care with layout and illustration, although Davidson is still the best value for money. I will continue to recommend it to my clinical students: they will need to read it and know it to pass final MB. Postgraduates will need to remember the facts, but also to be able to place them in a broader perspective. The older consultant will still happily read it, and to get to know the authors themselves is really to complete your medical education. Dr John Macleod and his team have successfully kept alive the primary objective 'to provide a rational and easily comprehensible basis for the practice of medicine'. The book is economical in price and compact in size, but still contains the essential truths for the practice of good medicine.

959 citations

Book ChapterDOI
TL;DR: The results of the studies that permit some generalizations on the catalytic mechanism of glycoside hydrolases from widely differing sources and with different sugar and aglycon specificities and that have become available over the past 15 years are discussed.
Abstract: Publisher Summary This chapter discusses the results of the studies that permit some generalizations on the catalytic mechanism of glycoside hydrolases from widely differing sources and with different sugar and aglycon specificities and that have become available over the past 15 years. The strong inhibition of glycosidases by aldonolactones was first mentioned in 1940 by Japanese workers who studied β- D -glucosidases from Aspergillus (Taka-diastase) and almonds. Even though both of these groups of compounds are derived from normal substrates by only a minor modification of the glycon moiety, they are discussed together with pseudosubstrates because their reactions with glycosidases show, in many cases, unusual kinetic features. The information relevant to the mechanism of an enzyme-catalyzed reaction can, in general, only be obtained from irreversible inhibitors that react specifically at the active site, and thereby inactivate the enzyme. In many cases, inhibition studies were not carried out to obtain information on the reaction mechanism, but for other purposes. Thus, only inhibitors were tested that were considered suitable for the particular project, for example, studies on the biological function of the enzyme where glycosylamines and aldonolactones are unsuitable.

506 citations

Journal ArticleDOI
28 Sep 1964-JAMA
TL;DR: Dr. Henry, as director of a large laboratory specializing in clinical chemistry, is in a unique position for acquiring a personal familiarity with a wide variety of chemical methods, and his book covers basic principles of analytical methods such as colorimetry, spectrophotometry, and flame photometry.
Abstract: Dr. Henry, as director of a large laboratory specializing in clinical chemistry, is in a unique position for acquiring a personal familiarity with a wide variety of chemical methods. Surveying the literature of clinical chemistry, evaluating hundreds of published methods, and selecting that small fraction of material which can be included in a book certainly constitute an impressive task. Not since publication of Peters and Van Slyke's classic Quantitative Clinical Chemistry has anyone been courageous enough to undertake this project, and Dr. Henry has succeeded remarkably well. The first chapters of the book cover basic principles of analytical methods such as colorimetry, spectrophotometry, and flame photometry. The remaining chapters deal with analytical methods for specific substances, and for each substance one or two methods are given in sufficient detail to permit use of the book as a laboratory manual. No attempt is made to include methods such as gas chromatography

275 citations

Journal ArticleDOI
TL;DR: It is shown that iminopentitols have considerable potential as glycosidase inhibitors, and was found to be identical to an alkaloid recently isolated from Angylocalyx boutiqueanus.

210 citations

Journal ArticleDOI
11 May 1946-Nature
TL;DR: Tackholm and Tackholm as mentioned in this paper presented an accurate and up-to-date taxonomic account of the wild and cultivated flora of Egypt, including the ephemeral flora of the deserts and the mountains and mountain valleys of Sinai and the Elba mountains.
Abstract: THAT Egypt is 'the gift of the Nile' may be true from the point of view of human civilization but such a phrase would be misleading if applied to the plant-life of the country. Even the weed flora of the canals and cultivated land is not uniform, and to this must be added the ephemeral flora of the deserts, and the mountains and mountain valleys of Sinai and the Elba mountains. Many botanists have explored Egypt and much has been published regarding both the wild and cultivated flora. However, the need for an accurate and up-to-date taxonomic account cannot be gainsaid, and the present work* by Mrs. Tackholm and the late Prof. G. Tackholm is intended to meet this need.

209 citations