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1.
The grey‐crowned babbler (Pomatostomus temporalis) is a cooperative breeding bird species in which nonbreeding helpers of both sexes care for the young of breeding individuals. To measure the genetic relatedness between breeders and their offspring and helpers, we developed nine microsatellite markers. Most of the loci were highly polymorphic. These loci will be useful in understanding the evolution and maintenance of cooperative breeding and helping behaviour in this species.  相似文献   
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The antimalarial agent chloroquine is known for high affinity for melanin. This 4-aminoquinoline derivative was examined for anti-melanoma activity and uptake into melanoma cells. Chloroquine inhibited growth of cultured melanoma cells; the effect was much greater to a moderately pigmented cell line HMV-II than to a nonpigmented HMV-I. Treatment with chloroquine at a dose of 62 mg/kg i.p. for 12 days prolonged by 71% the life span of mice bearing B16 melanoma, while 24-day treatment at 31 mg/kg resulted in a 81% increase in life span. HMV-II cells showed a two-fold increase in up-take of chloroquine as compared with HMV-I cells. Chloroquine, 24 hr after administration to mice implanted s.c. with B16 melanoma, was selectively accumulated in the pigmented tissues, melanoma and eyes. Other nonpigmented tissues such as the liver, lung, and kidney showed rapid uptake (within 1 hr) and release. These results suggest that chloroquine is toxic to pigmented melanoma cells, the process being partly mediated by binding to melanin  相似文献   
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KEISUKE UEDA 《Ibis》1989,131(2):257-262
In a population of Fan-tailed Warblers Cisticola juncidis near Osaka, Japan, the males were polygynous, building a succession of elaborate courtship nests within their territories, and advertising them to females. Nest desertion by females frequently occurred early in the breeding cycle. Deserted nests were generally left untouched, but 17 out of 88 territorial males cleaned and re-used 20 of 79 nests deserted by females for their next courtship. The frequency of nest re-use increased with season. Of the re-used nests six (300%) were re-occupied by secondary females. Newly built nests were preferred to the 'second-hand' nests, probably because new nests were likely to last longer. Breeding success did not differ between the two categories of nests. In males, nest re-use seems to save time and energy expenditure for additional mating.  相似文献   
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The lipids extracted from Chlorella cells at different developmentalstages were separated by chromatography on silicic acid into"nonpolar" (chloroform-eluate) and "polar" (methanol-eluate)lipid fractions. The lipids were also subjected to florisilchromatography to fractionate neutral glycerides and free fattyacids. Gas-liquid chromatographic analysis of these fractions has revealeda marked difference in their fatty acid compositions which werefound to undergo characteristic changes during the course ofalgal cell cycle. It was found that the fatty acids in the "nonpolar"lipid (fat) fraction are synthesized during the growth phasein the light and consumed during the process of cellular division. (Received September 24, 1966; )  相似文献   
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Morning dew appears to be an important factor in the habitat of Tripospermum species. It affects both conidial development and liberation.  相似文献   
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The Arctic Warbler Phylloscopus borealis breeds across the northern Palaearctic and northwestern‐most Nearctic, from northern Scandinavia to Alaska, extending south to southern Japan, and winters in Southeast Asia, the Philippines and Indonesia. Several subspecies have been described based on subtle morphological characteristics, although the taxonomy varies considerably among different authors. A recent study (T. Saitoh et al. (2010) BMC Evol. Biol. 10 : 35) identified three main mitochondrial DNA clades, corresponding to: (1) continental Eurasia and Alaska, (2) south Kamchatka, Sakhalin and northeast Hokkaido, and (3) most of Japan (Honshu, Shikoku, Kyushu). These three clades were estimated to have diverged during the late Pliocene to early Pleistocene (border at c. 2.6 million years ago). Differences in morphometrics have also been reported among members of the three clades (T. Saitoh et al. (2008) Ornithol. Sci. 7 : 135–142). Here we analyse songs and calls from throughout the range of the Arctic Warbler, and conclude that these differ markedly and consistently among the populations representing the three mitochondrial clades. Kurile populations, for which no sequence data are available, are shown to belong to the second clade. To determine the correct application of available scientific names, mitochondrial DNA was sequenced from three name‐bearing type specimens collected on migration or in the winter quarters. Based on the congruent variation in mitochondrial DNA, morphology and vocalizations, we propose that three species be recognized: Arctic Warbler Phylloscopus borealis (sensu stricto) (continental Eurasia and Alaska), Kamchatka Leaf Warbler Phylloscopus examinandus (Kamchatka (at least the southern part), Sakhalin, Hokkaido and Kurile Islands), and Japanese Leaf Warbler Phylloscopus xanthodryas (Japan except Hokkaido).  相似文献   
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ABSTRACT. Blepharisma cells were attracted by a pellet of live bacteria (Enterobacter) which was separated from the Blepharisma suspension by a cellulose membrane (fractionation: M.W. 14,000). The cells, however, were not attracted by killed bacteria. Crude and heat-treated supernatants obtained from bacterial suspension also induced chemoaccumulation of cells. These results suggest that the cells of Blepharisma detect certain small molecules, produced by live bacteria, that can pass through the cellulose membrane and are stable to heat. From the live bacteria supernatant, several ninhydrin-positive substances were isolated by means of two-dimensional thin-layer chromatography. Several of the spots contained substances that attracted the cells, indicating that certain ninhydrin-positive components, such as peptides or free amino acids (probably products of bacterial metabolism), may serve as a signal for food.  相似文献   
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