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71.
The in vitro effect of cisplatin or rIFN-Y on the intracellular free calcium, protein kinase activity and ATP content of non-adherent mononuclear cells (nMNC) from human peripheral blood was assessed. We observed that treatment of nMNC with cisplatin enhanced the [Ca2+]i, ATP level, and protein kinase activity; whereas rIFN-Y-treated nMNC showed significant rises in ATP level and protein kinase activity only. We also observed that cisplatin-treated nMNC showed an instantaneous rise in [Ca2+]i when NK-sensitive K562 cells were added to the effector cells.  相似文献   
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Complexes of 5-iodouracil (5IU) with Mn(II), Co(II), Cu(II), Zn(II), and Cd(II) ions have been prepared, characterized, and subjected to a screening system for evaluation of antitumor activity against Sarcoma-180 (S-180) and L 929 tumor cells. The complexes were characterized by their elemental analysis, infrared spectra, electronic spectra, magnetic measurements, and powder x-ray diffraction. The antitumor activity results indicate that some complexes have good antitumor activity both in vivo and in vitro against S-180 and L 929 tumor cells.  相似文献   
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Co-Extinctions of Tropical Butterflies and their Hostplants   总被引:4,自引:0,他引:4  
The co‐extinction of interdependent species in relation to massive, long–term habitat disturbance has not been thoroughly investigated. Using logistic regression analyses, we examined the relationship between the loss of butterflies and their specific hostplants from the tropical island of Singapore and report the probable occurrence of their co–extinctions at the community level. Our simulation shows that the number of extinct butterfly species is expected to increase exponentially with that of extinct hostplants. The close association between butterflies and their hostplants suggests that the preservation of whole habitats is urgently needed if we are to avoid the possible cascading effects of species (co‐)extinctions.  相似文献   
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Key message

Genetic locus for tetralocular ovary ( tet - o ) in Brassica rapa was identified and it was shown that the number of locules and width of silique are associated.

Abstract

Brassica rapa is a highly polymorphic species containing many vegetables and oleiferous types. An interesting group of oleiferous types is the yellow sarson group (subspecies trilocularis) grown mostly in eastern India. This group contains lines that have bilocular ovaries, a defining trait of Brassicaceae, but also lines that have tetralocular ovaries. Yellow sarson lines commonly have high silique width which is further enhanced in the tetralocular types. We mapped the locus influencing tetralocular ovary in B. rapa using three mapping populations (F2, F6 and F7) derived from a cross between Chiifu (subspecies pekinensis, having bilocular ovary) and Tetralocular (having tetralocular ovary). QTL mapping of silique width was undertaken using the three mapping populations and a F2 population derived from a cross between Chiifu and YSPB-24 (a bilocular line belonging to yellow sarson group). Qualitative mapping of the trait governing locule number (tet-o) in B. rapa mapped the locus to linkage group A4. QTL mapping for silique width detected a major QTL on LG A4, co-mapping with the tet-o locus in bilocular/tetralocular cross. This QTL was not detected in the bilocular/bilocular cross. Saturation mapping of the tet-o region with SNP markers identified Bra034340, a homologue of CLAVATA3 of Arabidopsis thaliana, as the candidate gene for locule number. A C → T transition at position 176 of the coding sequence of Bra034340 revealed co-segregation with the tetralocular phenotype. The study of silique related traits is of interest both for understanding evolution under artificial selection and for breeding of cultivated Brassica species.  相似文献   
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