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Summary A new translocation between chromsomes 2 and 8 t(2p; 8q+), was found in fresh lymphoma cells from a Japanese patient with Epstein-Barr virus-carrying Burkitt's lymphoma, and in a lymphoma cell line derived from this patient. There was no 14q+ translocation, as has been previously described in African and North American Burkitt's lymphomas.Supported by a grant-in-aid for Cancer Research (52-11) from the Ministry of Health and Welfare of Japan.  相似文献   
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Yoshida T  Jones LE  Ellner SP  Hairston NG 《Nature》2006,439(7072):E1-2; discussion E2
A variety of mechanisms can theoretically produce competitive coexistence in nature, making it hard to identify a single explanation for the maintenance of diversity in any particular system. Based on laboratory experiments with a consumer-resource system of crustacean Daphnia eating algae, Nelson et al. suggest that maintenance of genetic diversity in the consumer populations they studied depends only on the dynamics of the population structure of the consumer. We suggest that the differences in Daphnia genetic diversity that they find for different experimental treatments could equally be explained by a simple, well known mechanism: the number of coexisting competitors cannot exceed the number of shared resources. Here we confirm this possibility by using a simple mathematical model and suggest that more than one mechanism may account for the maintenance of genetic diversity observed by Nelson et al. in their system.  相似文献   
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2/8 translocation in a Japanese Burkitt's lymphoma.   总被引:1,自引:0,他引:1  
A new translocation between chromosomes 2 and 8, t(2p-; 8q+), was found in fresh lymphoma cells from a Japanese patient with Epstein-Barr virus-carrying Burkitt's lymphoma, and in a lymphoma cell line derived from this patient. There was no 14q+ translocation, as has been previously described in African and North American Burkitt's lymphomas.  相似文献   
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By exome sequencing, we found de novo SMARCB1 mutations in two of five individuals with typical Coffin-Siris syndrome (CSS), a rare autosomal dominant anomaly syndrome. As SMARCB1 encodes a subunit of the SWItch/Sucrose NonFermenting (SWI/SNF) complex, we screened 15 other genes encoding subunits of this complex in 23 individuals with CSS. Twenty affected individuals (87%) each had a germline mutation in one of six SWI/SNF subunit genes, including SMARCB1, SMARCA4, SMARCA2, SMARCE1, ARID1A and ARID1B.  相似文献   
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Rutile (TiO2) is heavily used in pigments and colorants, and the most abundant source of rutile is ilmenite. Upon oxidation of ilmenite, rutile can be formed with modest energy consumption; furthermore, after leaching, only a few byproducts are formed. Unfortunately, one drawback is the necessarily long oxidative process of typically used methods. In this study, we show that a fluidized bed reactor can be used to oxidize ilmenite ore to rapidly form rutile and pseudobrookite (Fe2TiO5) phases. Ilmenite was oxidized with 5vol% O2 in Ar at temperatures of 1173 K or 1223 K and subsequently leached using a diluted H2SO4 solution to dissolve the pseudobrookite phase. The effects of acid concentration, temperature, and cooling rate after oxidation were investigated. We show that the ilmenite was rapidly oxidized to form rutile and pseudobrookite phases at 1173 and 1223 K in a 5vol% O2/95vol% Ar environment within 40 min. The final maximum rutile yield was 84.2mol% after leaching in (1 + 1) H2SO4 solution at 393 K for 12 h.  相似文献   
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Summary A leukemic T-cell line (TALL-1) was serially transplanted for 5 passages into newborn hamsters treated with antilymphocyte serum. This cell line was derived from a leukemic patient with clinical evidence of ocular involvement. I.p. implantation of 1–3×107 cells resulted in disseminated growth of tumors in all 15 recipients after 23–41 days and 8 of them showed leukemic infiltration of the uveal tract of one or both eyes.Supported by a Cancer Research Grant from the Ministry of Health and Welfare of Japan.  相似文献   
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Zusammenfassung Antikörpertiter gegen EBV wurden in 40 gepaarten Seren von pränatalen Müttern und Neugeborenen gleichzeitig mit indirekter Immunofluoreszenz bestimmt. In 95% hatten sowohl Mütter als auch Neugeborene den Antikörper. Die Titer der Mütter waren mehrheitlich gleich oder höher jenen der Neugeborenen, woraus geschlossen wird, dass der Antikörper gegen EBV von der Mutter diaplacentar auf den Fetus übertragen werden kann.  相似文献   
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Yoshida T  Jones LE  Ellner SP  Fussmann GF  Hairston NG 《Nature》2003,424(6946):303-306
Ecological and evolutionary dynamics can occur on similar timescales. However, theoretical predictions of how rapid evolution can affect ecological dynamics are inconclusive and often depend on untested model assumptions. Here we report that rapid prey evolution in response to oscillating predator density affects predator-prey (rotifer-algal) cycles in laboratory microcosms. Our experiments tested explicit predictions from a model for our system that allows prey evolution. We verified the predicted existence of an evolutionary tradeoff between algal competitive ability and defence against consumption, and examined its effects on cycle dynamics by manipulating the evolutionary potential of the prey population. Single-clone algal cultures (lacking genetic variability) produced short cycle periods and typical quarter-period phase lags between prey and predator densities, whereas multi-clonal (genetically variable) algal cultures produced long cycles with prey and predator densities nearly out of phase, exactly as predicted. These results confirm that prey evolution can substantially alter predator-prey dynamics, and therefore that attempts to understand population oscillations in nature cannot neglect potential effects from ongoing rapid evolution.  相似文献   
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