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| 1 | Geochemistry of lamprophyres associated with uranium mineralization, Southeastern Desert, Egypt显示文摘Two brecciated shear zones (NNW-SSE) are found crosscutting cataclastic rocks. The cataclastic rocks (3.0 km2) occupy the core of the granitic pluton and enclose a roof pendant of mafic-ultramafic rocks. The NNW-SSE-extending lamprophyre dykes vary in thickness from 0.5 m to 1 m and up to 800 m long, cutting the cataclastic rocks and are composed mainly of plagioclases, amphiboles, relics of pyroxenes and K-feldspar phenocrysts embedded in fine-grained groundmass. They are characterized as being peraluminous, calc-alkaline in composition (chemical trap) and enriched in calcite, sulfide and P2O5. The lamprophyres were affected by hydrothermal alteration (chlorite-carbonate alteration) while the cataclastic rocks were affected by diagenetic alteration (K-feldspar-albite alteration). Uranium mineralization is the product of hydrothermal events and has been investigated by X-ray diffraction (XRD) and environmental scanning electron microscopy (ESEM), involving primary uranium minerals (U3O8) and secondary uranium minerals (uranophane and beta-uranophane, kasolite, torbernite, autonite and meta-autonite) in addition to U- bearing minerals (astrocyanite, betafite and fergusonite). The presence of different mineral parageneses associated with clay minerals indicates that the lamprophyres were subjected to acidic and alkaline mineralizing solutions. Moreover, the U-Zr/U, U-Ce/U values show negative correlations, confirming U-enrichment in both cataclastic rocks and shear zones while the Th-eU/eTh, Th-Zr/Th and Th-Ce/Th values show negative correlations, indicating that the U-bearing solutions are rich in Th in the cataclastic rocks only. | Mohamed E. Ibrahim Mohamed M. El-Tokhi Gehad M. Saleh Mamdouh A. Hassan Mohamed A. Rashed | 2007 | Chinese Journal Of Geochemistry2007，26，4： | 2 |
| 2 | Rare metal-bearing pegmatites from the Southeastern Desert of Egypt:Geology,geochemical characteristics,and petrogenesis显示文摘The pegmatite province of the Southeastern Desert (SED) is part of a pegmatite district that extends from Egypt (extends to 1200 km2). Rare metal pegmatites are divided into (1) unzoned, Sn-mineralized; (2) zoned Li, Nb, Ta and Be-bearing; and (3) pegmatites and pegmatites containing colored, gem-quality tourmaline. The Rb/Sr data reflect a crustal origin for the rare metal pegmatites and indicate that the original SED magma was generated during the peak of regional metamorphism and predates the intrusion of post-tectonic leucogranites. These bodies developed an early border zone consisting of coarse to very coarse muscovite+quartz+alkali feldspar, followed by an intermediate zone of dominant quartz+feldspar+muscovite rock. Garnet, tourmaline, beryl, galena, pyrite, amblygonite, apatite and monazite are rare accessories in both zones. Cassiterite tends to concentrate in replacement zones and along fractures in albite+quartz+muscovite-rich portions. The highest concentrations of cassiterite occur in irregular greisenized zones which consist dominantly of micaceous aggregates of green Li-rich muscovite, quartz, albite and coarse-grained cassiterite. The different metasomatic post-solidification alterations include sodic and potassic metasomatism, greisenization and tourmalinization. Geochemically, the pegmatite-generating granites have a metaluminous composition, showing a differentiation trend from coarse-grained, unfractionated plagioclase-rich granite towards highly fractionated fine- to medium-grained, local albite-rich rock. Economically important ore minerals introduced by volatile-rich, rare metal-bearing fluids, either primarily or during the breakdown of the primary mineral assemblages, are niobium-tantalum oxides, Sn-oxides (cassiterite), Li-silicates (petalite, spodumene, euctyptite, and pollucite), Li-phosphates (amblygonite, montebrasite and lithopilite) and minor REE-minerals (Hf-zircon, monazite, xenotime, thorian, loparite and yttrio-fluorite). The pollucite is typically associated with spodumene, petalite, amblygonite, quartz and feldspar. The primary pollucite has Si/Al (at) ratios of 2.53-2.65 and CRK of 79.5- 82.2. Thorian loparite is essentially a member of the loparite (NaLREETi2O6)-lueshite (NaNbO3)-ThTi2O6-ThNb4O12 quaternary system with low or negligible contents of other end-member compositions. The mineral compositionally evolved from niobian loparite to niobian thorian and thorian loparite gave rise to ceriobetafite and belyankinite with high ThO2 contents. Thorian loparite is metamict or partly metamict and upon heating regains a structure close to that of synthetic loparite NaLaTi2O6. | Gehad M.Saleh | 2007 | Chinese Journal Of Geochemistry2007，26，1： | 2 |
| 3 | Differing requirements for CCR4,E-selectin,and α4β1 for the migration of memory CD4 and activated T cells to dermal inflammation显示文摘 | Gehad A Al-Banna NA Vaci M | | 0，，01： | 1 |
| 4 | Human TH9 cells are skin- tropic and have autocrine and paracrine proinflammatory capacity 显示文摘 | Schlapbach C Gehad A Yang C | 2014 | Sci Transl Med2014，6，219： | 1 |
| 5 | Tumor- specific T cells in human Merkel eellearcinomas: a possible role for Tregs and T- cell exhaustion in reducing T- cell responses 显示文摘 | Dowlatshahi M Huang V Gehad AE | 2013 | J Invest Dermatol2013，133，7： | 1 |
| 6 | Allelic polymorphism of MSP2 gene in severe P. falciparum malaria in an area of low and seasonal transmission显示文摘 | Ishraga E. A-Elbasit Gehad ElGhazali Thoraya M. E. A-Elgadir Amel A. Hamad Hamza A. Babiker Mustafa I. Elbashir Hayder A. Giha | 2007 | Parasitology Research2007，，1： | 1 |
| 7 | Protective and therapeutic potentials of Dunaliella salina on aging-associated cardiac dysfunction in rats显示文摘Objective: To investigate the possible protective and/or therapeutic potentials of Dunaliella salina(D. salina) biomass, its carotenoid and polar fractions on cardiac dysfunction associated with D-galactose(D-GAL) induced aging in rats. Methods: Aging associated cardiac dysfunction was induced in rats by injection of D-GAL(200 mg/kg; i.p) for 8 weeks. D-GAL injected rats were treated with two regimens; protective regimen where D. salina biomass(250 mg/kg), its carotenoid(250 μg/kg) and polar(250 μg/kg) fractions were given orally for two weeks concurrently with D-GAL injection as well as treatment regimen where the three treatments were given orally for 28 consecutive days after D-GAL injection. Results: D-GAL injection for 8 weeks was accompanied with dramatic electrocardiographic changes as well as profound elevation in serum levels of homocysteine, creatinine kinase isoenzyme and lactate dehydrogenase in addition to the reduction of the cardiac content of glucose trasporter 4. D-GAL also induced reduction in cardiac superoxide dismutase activity and elevation of inducible nitric oxide synthetase and interleukin-6. On the other hand, oral administration of D. salina carotenoid fraction as well as the total biomass significantly attenuated the D-GAL-induced disturbances in the above mentioned parameters where the protective regimen appeared more successful in controlling the manifestations of cardiac dysfunction. The histopathological examination further emphasized the promising results. Besides, the HPLC analysis of the carotenoid fraction of D. salina revealed the presence of 2.31%. salina carotenoid fraction as well as the total biomass amelior β-carotene. Conclusions: Date D-GAL-induced aging associated cardiac dysfunction which is attributed to the potent antioxidant activity of β-carotene. | Farouk K.El-Baz Gehad A.Abdel Jaleel Dalia O.Saleh Rehab A.Hussein | 2018 | Asian Pacific Journal of Tropical Biomedicine2018，8，8： | 1 |
| 8 | Geochemical characteristics and spectrometric prospecting in the muscovite-bearing pegmatites and granites, southeastern Aswan, Egypt显示文摘Rare metal mineralization of Sn, Nb-Ta and W is encountered in the Gebel Dihmit area (GDA), south- eastern Aswan, Egypt. The mineralization is related to muscovite granites and their pegmatite derivatives. The peg- matites are divided into three types according to their main mineral assemblages: K-feldspar-muscovite-tourmaline, K-feldspar-albite-muscovite and albite-K-feldspar-lepidolite veins. Petrogenetic studies indicate that Sn and Nb-Ta mineralization extends from the late-magmatic stage to the pegmatite and hydrothermal stages of the (GDA) suite. The albite-K-feldspar-lepidolite granite is composed dominantly of albite, lepidolote, and quartz, with topaz, K-feldspar and amblygonite. The accessory minerals are zircon, monazite, pollucite, columbite-tantalite, microlite and Ta-rich cassiterite. Phenocrysts of quartz, topaz and K-feldspar contain abundant inclusions of albite laths and occasional lepidolite crystals along growth zones (snowball texture), indicating simultaneous crystallization from a subsolvus, residual magma. The origin of the pegmatites is attributed to extreme differentiation by fractional crystal- lization of a granitic magma. The economic potential for rare metals was evaluated in the geochemical discrimination diagrams. Accordingly, some of the pegmatites are not only highly differentiated in terms of alkalis, but also the promising targets for small-scale Ta and, to a less extent, Sn. The pegmatites also provide the first example of Fe-Mn and Nb-Ta fractionation in successive generations of granites to cassiterite-bearing pegmatites, which perfectly ex- hibit similar fractionation trends established for primary columbite-tantalite in the corresponding categories of peg- matites. Uranium and Th of magmatic origin are indicated by the presence of thorite and allanite, whereas evidence of hydrothermal mineralization is the alteration of rock- foring minerals such as feldspar and the formation of sec- ondary minerals such as uranophane.. | Gehad M. Saleh Mohamed M. El Galy Mohamed A. Obeid | 2008 | Chinese Journal Of Geochemistry2008，27，1： | 1 |
| 9 | The chromite deposits associated with ophiolite complexes, Southeastern Desert, Egypt: Petrological and geochemical characteristics and mineralization显示文摘The podiform chromitites occur in a well-preserved mantle sequence consisting of lherzolite-harzburgite with abundant lenses of olivine dunite. The podiform chromitite deposits are common as small and irregularly shaped masses in the Southeastern Desert (SED) of Egypt. The podiform chromitites exhibit a wide range of compositions from high Cr to high Al varieties. The Cr of chrome spinel ranges from 0.67 to 0.88 in olivine-dunite, quite similar to that of the high-Cr chromitite, whereas it is around 0.62 in lherzolite-harzburgite. Primary hydrous mineral inclusions, amphibole and phlogopite, in chrome spinel have been reported for the first time from the Pan-African Proterozoic podiform chromitites. On the other hand, petrographic and geochemical evidence suggests that podiform chromitites in the SED of Egypt were formed as a result of crystallization of mafic melts, probably of boninitic composition, the boninitic parental magmas were probably produced by a second stage of melting above a subduction zone. Three types of chromite ores can be distinguished within the SED of Egypt: (a) sulphide-poor podiform ores; (b) brecciated ores; and (c) sulphide-rich ores. Two textural types of inclusions in chromite are distinguished: (1) primary silicate inclusions generally have high Mg-number (>96), Cr and Ni, and are dominated by pargasitic amphibole, forsterite, diopside, enstatite and Na-phlogopite. A diversity of primary and secondary platinum group minerals (PGM) is described from the chromitites, including alloys, sulphides, sulpharsenides and arsenides of Ru, Os, Ir, Rh, Ni, Cu, Fe and Co; (2) in addition to primary PGM and hydrous silicates, the fluids are of low to moderate salinity, sodium-dominated aqueous solutions with complex gas contents. Variable amounts of water, hydrogen, hydrocarbons, carbon dioxides and nitrogen have been determined in inclusion-rich samples. The chondrite-normalized PGE patterns of lherzolite-harzburgite and olivine-dunite have negative Ir and Pt, and positive Pd and Au anomalies. Chromitites are homo-geneous in composition but texturally zoned on a large scale. They carry elevated IPGE, manifested in numerous, primary and secondary PGM phases. | Gehad M. Saleh | 2006 | Chinese Journal Of Geochemistry2006，25，4： | 1 |
| 10 | Mixed ligand complexes of bis(phenylimine) Schiff base ligands incorporating pyridinium moiety:Synthesis,characterization and antibacterial activity显示文摘 | GEHAD G MOHAMED Z H ABD E W | 2005 | Spectrochimica Acta Part A2005，61，6： | 1 |
| 11 | Effects of genetic selection and MHC haplotypes on lymphocyte proliferation and interleukin 2 like ac tivity in chicken lines selected for high and low antibody production against sheep red blood cells显示文摘 | GEHAD A E MASHALY M M SIEGEL H S | 1999 | Vet Immunol Immunopathol1999，68，： | 1 |
| 12 | Tumor-specific T cells in human Merkel cell carcinomas: a possible role for Tregs and T-cell exhaustion in reducing T-cell responses显示文摘 | Dowlatshahi M Huang V Gehad AE | 2013 | J Invest Der- matol2013，133，7： | 1 |
| 13 | Human TH9 cells are skin-tropic and have autocrine and paracrine proinflamma- tory capacity显示文摘 | Schlapbach C Gehad A Yang C | 2014 | Sci Transl Med2014，6，21： | 1 |
| 14 | The effect of lighting program and melatonin on the alleviation of the negative impact of heat stress on the immune response in broiler chickens 显示文摘 | ABBAS A O GEHAD A E HENDRICKS G L | 2007 | Inter J Poult Sci2007，6，9： | 1 |
| 15 | Preparation of Macrocyclic Schiff-base Ligand and An- tibacterial Activities of Transition Metal Complexes Thereof 显示文摘 | GEHAD G M MOHAMED M O MOHSEN S A E E | 2011 | Toxicolog Environ Chemistry2011，93，1： | 1 |
| 16 | Metal complexes of Schiff base derived from sulphametrole and o -vanilin显示文摘 | Gehad G. Mohamed Carmen M. Sharaby | 2006 | Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy2006，，4： | 1 |
| 17 | Nitric oxide-producing myeloid- derived suppressor cells inhibit vascular e-selectin expression in human squamous cell carcinomas显示文摘 | Gehad AE Lichtman MK Schmults CD | 2012 | J Invest Dermatol2012，132，11： | 1 |
| 18 | Allelic polymorphism of MSP2 gene in severe P. falciparum malaria in an area of low and seasonal transmission显示文摘 | Ishraga E. A-Elbasit Gehad ElGhazali Thoraya M. E. A-Elgadir Amel A. Hamad Hamza A. Babiker Mustafa I. Elbashir Hayder A. Giha | 2007 | Parasitology Research2007，，1： | 1 |
| 19 | Nitric oxide-producing myeloid-derived suppressor cells inhibit vascular E-selectin expression in human squamous cell carcinomas显示文摘 | Gehad AE Lichtman MK Schmults CD | 2012 | J Invest Dermatol2012，132，11： | 1 |
| 20 | Effects of photoperiod and melatonin on lymphocyte ac- tivities in male broiler chickens 显示文摘 | Kliger C A Gehad A E Hulet | 2000 | Poultry Sci- ence2000，79，1： | 1 |
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