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21.
Synopsis Bagrids in Bahr Shebeen Nilotic canal depend mainly on fish, insects and shrimp as well as fish embryos for food and their stomachs included runoff materials (e.g. plant foliage, glass, black crystals, coloured gravel). B. bayad maximised its efficiency of catching prey catfish by face to face attack to avoid damage by the prey's pectoral and dorsal spines. In the size classes of 10 to 30 cm standard length, B. bayad and B. docmac show diet overlap and interact with each other especially with respect to tilapias as prey. After this length, B. docmac, aided by its relatively larger mouth, shifted to larger size of tilapias to coexist with B. bayad. 相似文献
22.
Viqar Uddin Ahmad Mohammad Ghani Shah Faryal Vali Mohammad Nargis Ismail Mushtaq Noorwala 《Phytochemistry》1991,30(12)
A new flavone glucoside macrophylloside has been isolated from the whole plant of Primula macrophylla and its structure was determined by spectroscopic methods as 2′-hydroxy-7-O-β-
-glucopyranosyloxyflavone. Sitosterol glucoside was also isolated for the first time from this plant. 相似文献
23.
24.
Dr. Nuzha M. Al-Taho Sami H. Al-Amad Fadilah A. Al-Salameen Ekkehard Spanier Mohammad Z. Haider 《Current microbiology》1991,22(3):199-202
Fourteen recombinant plasmids were constructed by inserting fragments of pSAS, a naturally occurring plasmid ofMethylophilus spp. KISRI-5, into the multiple cloning sites of pUC19. Six recombinants and three knownEscherichia coli plasmids were used to transform three thermotolerant methylotrophic KISRI strains by use of an optimized protocol of electroporation. Analysis of transformants for plasmid DNA showed that all plasmids were stable in the methylotrophic hosts. These studies offer opportunities to developMethylophilus spp. as host-vector systems. 相似文献
25.
Sequence analysis of the simian foamy virus type 1 genome. 总被引:11,自引:0,他引:11
26.
A. Mohammad J.S.M. Peiris E.A. Wijewanta S. Mahalingam G. Gunasekara 《FEMS microbiology letters》1985,26(3):281-283
Abstract 273 Strains of Escherichia coli isolated from diarrhoeic and healthy control cattle and buffalo calves in Sri Lanka, were tested for Verocytotoxin (VT) and for heat-stable (ST) and heat-labile (LT) enterotoxins. VT and ST toxigenic E. coli were significantly associated with diarrhoea, accounting for 28% and 18% of diarrhoeic episodes, respectively. LT toxigenic E. coli were not significantly associated with diarrhoea. 相似文献
27.
28.
Lineage-specific expression of c-fos and c-fms in human hematopoietic cells: Discrepancies with the in vitro differentiation of leukemia cells 总被引:2,自引:0,他引:2
Hans Kreipe Heinz J. Radzun Klaus Heidorn Mohammad Reza Parwaresch Bernard Verrier Rolf Müller 《Differentiation; research in biological diversity》1986,33(1):56-60
In vitro differentiation studies using the bipotential human leukemia cell line, HL60, have indicated that high levels of expression of two proto-oncogenes, c-fos and c-fms, are restricted to the myelomonocytic lineage. No such expression has been detected in induced granulocytic cells. In striking contrast to these observations, we found that c-fos mRNA levels are very high in purified human granulocytes, but barely detectable in blood monocytes and tissue macrophages. Human granulocytes contain, however, relatively low levels of c-fos protein, indicating that c-fos mRNA is inefficiently translated or that the protein is rapidly degraded in these cells. In closer agreement with the in vitro results, the level of the expression of c-fms is high in purified blood monocytes and undetectable in granulocytes. We found, however, that the evolution of monocytes into tissue macrophages is accompanied by a significant decrease in c-fms expression, suggesting that the function of c-fms is restricted to specific stages of monocytic differentiation. Our observations also show that results obtained using in vitro differentiation systems have to be regarded with caution, since they may not reflect the in vivo situation. 相似文献
29.
Serotypes of verocytotoxigenic Escherichia coli isolated from cattle and buffalo calf diarrhoea 总被引:1,自引:0,他引:1
Abstract Parasporal crystals of the recently isolated Bacillus thuringiensis var. tenebrionis are toxic for coleopteran larvae. Unlike those of other strains they are soluble either in aqueous solutions of NaBr at neutral pH or in water after titration to pH values above pH 10.0. The dissolved crystal protein readily forms crystals after removal of the salt or neutralization. The crystal protein was not found to differ much in the amino acid composition from other crystal proteins. The parasporal crystals are composed of subunits of M r 68 000 which are not linked by disulfide bridges. 相似文献
30.
M. Hayat 《BioControl》1972,17(1):99-106
An account of the Indian species of the genusEretmocerus
Haldeman is given. Three new species (E. indicus sp. n.,E. mashhoodi sp. n.,E. gunturiensis sp. n.) are described. Three species (E. haldemani
Howard,E. mundus
Mercet,E. corni
Haldeman) are reported for the first time from India. A revised key to the known species of the genus is also given.
Résumé Une révision des espèces indiennes du genreEretmocerus Haldeman est donnée. Trois nouvelles espèces (E. indicus, E. mashhoodi, E. gunturiensis) sont décrites, trois autres espèces (E. haldemani Howard,E. mundus Mercet,E. corni Haldeman) sont signalées pour la première fois de l’Inde. Une clé révisée des espèces connues de ce genre est proposée.相似文献