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991.
Male Ornithodoros (Pavlovskyella) erraticus infected with Borrelia crocidurae transferred the spirochetes to females during copulation. After the first and second gonotrophic cycles, spirochetes were observed in 23 and 37%, respectively, of the females. Venereal transfer by the polygamous male contributes significantly to supporting the B. crocidurae population in nature.  相似文献   
992.
993.
Macrobothridium rhynchobati n. g., n. sp. from the guitarfish Rhynchobatus granulatus in Kuwaiti waters in the Arabian Gulf is described and figured. The new genus differs from Echinobothrium in having a short unarmed peduncle and a posterior sucker-like structure in the terminal proglottid. It differs from Ditrachybothridium in having a powerful rostellum with dorsal and ventral groups of hooks and in having unarmed bothridia. A new family, the Macrobothridiidae, assigned to the order Diphyllidea is erected. Larval forms are described and figured.  相似文献   
994.
995.
996.
A cDNA encoding mouse stromelysin 1 was cloned and the 1740-bp sequence was determined. The deduced amino acid (aa) sequence was compared with stromelysin 1 sequences of other mammals. Comparison with a previously published incomplete aa sequence of mouse stromelysin 1 revealed three single aa differences.  相似文献   
997.
Preface     
Molecular and Cellular Biochemistry -  相似文献   
998.
The chemically inert trivalent ion cobalt(III) hexaammine, Co3+(NH3)6, was found to exert polyamine-like effects in enhancing certain cyclic nucleotide-independent protein kinase reactions catalyzed by nuclear enzyme preparations from rat ventral prostate or liver. At 1 mM, Co3+(NH3)6 stimulated chromatin- and also non-histone-protein-associated kinase activities with partially dephosphorylated phosvitin as substrate by 38% and 72% respectively, whereas chromatin-associated kinase-catalyzed phosphorylation of lysine-rich histones was not affected under the same conditions. 32P incorporation (from γ-32P-ATP) into endogenous protein substrates of chromatin or non-histone protein fractions catalyzed by their erdogencus kinase activity was increased by 47% and 153%, respectively. These effects of Co3+(NH3)6 were similar to those produced by 1mM spermine. Autoradiographic analysis of endogenous 32P-labelled nonhistone proteins revealed similar enhancements of the phosphorylation of several of the same proteins, induced by 1mM spermine or 1 mM Co3+(NH3)6 or 2mM spermidine. The stimulatory actions of polyamines or Co3+(NH3)6 were not mimicked by raising the ionic strength by addition of comparable concentrations of NaCl. The effects of 1 mM spermine and of 1 mM Co3+(NH3)6 tested separately were not additive. Phosphorylation of lysine-rich histones by beef heart cyclic AMP-dependent protein kinase was not affected by polyamines or Co3+(NH3)6 Various findings hint that the enhancement of cyclic nucleotide-independent kinase-catalyzed phosphorylation of certain protein substrates by spermidine, spermine and Co3+(NH3)6 is primarily due to interaction of these cations with appropriate protein substrates affecting their conformational status. Further, these effects of polyamines may be a reflection of their cationic charge properties rather than being dependent on any particular conformations assumed by the polyamines.  相似文献   
999.
Surface zooplankton were studied in Egyptian coastal watersof the Gulf of Aqaba, from bimonthly samples from July 1994to May 1995. Species diversity, numerical abundance and dynamicswere analysed for each taxon, at six sites, inside three Protectorates.A total of 62 taxa and species were identified. At all sites,copepods were predominant in the standing crop with an averageof 1945 ind. M–3 and formed {small tilde}75.5%, numerically,of the total zooplankton community. The meroplanktonic larvaeoccupied the second rank and they constituted {small tilde}19.7%of the total zooplankton. Seasonally, the main peak of zooplanktonabundance was recorded in winter (January) with an average of3510 ind. M–3 while September was characterized by thelowest density (1906 ind. m–3 The relatively higher diversityvalues were recorded at Ras Mohammed Protectorate and a progressivedecline in diversity was observed northward.  相似文献   
1000.
Pluviantaenia kassalensis n. g., n. sp. (Davaineidae), from the intestine of Pluvianus aegyptius (Charadriiformes, Glareolidae) in the Kassala area of the Sudan, differs from other davaineid cestodes in having an armed scolex with an inflated pseudorostellum terminating in two fan-shaped lobes, in the absence of suckers, the presence of a very large sucker-like genital atrium provided distally with a powerful sphincter, and the presence of a thin-walled cirrus-sac, smaller than the genital atrium, enclosing a robust, armed cirrus. The genital atrium cirrus-sac complex, but not the female organs, may be duplicated bilaterally and/or additional sets may occur in marginal or submarginal positions.  相似文献   
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