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1.
Ewing sarcoma, a pediatric tumor characterized by EWSR1-ETS fusions, is predominantly observed in populations of European ancestry. We performed a genome-wide association study (GWAS) of 401 French individuals with Ewing sarcoma, 684 unaffected French individuals and 3,668 unaffected individuals of European descent and living in the United States. We identified candidate risk loci at 1p36.22, 10q21 and 15q15. We replicated these loci in two independent sets of cases and controls. Joint analysis identified associations with rs9430161 (P = 1.4 × 10(-20); odds ratio (OR) = 2.2) located 25 kb upstream of TARDBP, rs224278 (P = 4.0 × 10(-17); OR = 1.7) located 5 kb upstream of EGR2 and, to a lesser extent, rs4924410 at 15q15 (P = 6.6 × 10(-9); OR = 1.5). The major risk haplotypes were less prevalent in Africans, suggesting that these loci could contribute to geographical differences in Ewing sarcoma incidence. TARDBP shares structural similarities with EWSR1 and FUS, which encode RNA binding proteins, and EGR2 is a target gene of EWSR1-ETS. Variants at these loci were associated with expression levels of TARDBP, ADO (encoding cysteamine dioxygenase) and EGR2.  相似文献   
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The efficacy of different hexacyanoferrates(II) in preventing the enteral absorption of 134Cs was studied in piglets. As compared to the controls, oral application of 134Cs together with KFe[Fe(CN)6], NH4Fe[Fe(CN)6], or Fe4[Fe(CN)6]3 resulted in a strong reduction of the 134 Cs-uptake by more than 97%. The decrease in enteral absorption depends on the dose of administered hexacyanoferrate(II), whereas differences between the compounds under study were small. The biological half-life of 134Cs in non-hexacyanoferrate(II) treated piglets was 21.6 +/- 3.3 days (mean +/- SD).  相似文献   
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Zusammenfassung Dank einer neuen Anwendung von Lymphknotenextrakten (statt Röntgenextrakten, Corticosteroiden, Antilymphozytenserum usw.) wird eine erhebliche Reduktion der immunologischen Reaktion erzielt, wenn die Tiere mit diesen Extrakten vorbehandelt und gleichzeitig mit Antigenen behandelt werden.

This investigation was supported in part by U.S.P.H.S. Research Grant No. CA-02624 from National Cancer Institute; and in part by an institutional grant to Detroit Institute of Cancer Research from United Foundation of greater Detroit allocated through Michigan Cancer Foundation and the Detroit General Hospital Research Corporation, and Newaygo County Cancer Society.  相似文献   
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Heck PR  Schmitz B  Baur H  Halliday AN  Wieler R 《Nature》2004,430(6997):323-325
Very large collisions in the asteroid belt could lead temporarily to a substantial increase in the rate of impacts of meteorites on Earth. Orbital simulations predict that fragments from such events may arrive considerably faster than the typical transit times of meteorites falling today, because in some large impacts part of the debris is transferred directly into a resonant orbit with Jupiter. Such an efficient meteorite delivery track, however, has not been verified. Here we report high-sensitivity measurements of noble gases produced by cosmic rays in chromite grains from a unique suite of fossil meteorites preserved in approximately 480 million year old sediments. The transfer times deduced from the noble gases are as short as approximately 10(5) years, and they increase with stratigraphic height in agreement with the estimated duration of sedimentation. These data provide powerful evidence that this unusual meteorite occurrence was the result of a long-lasting rain of meteorites following the destruction of an asteroid, and show that at least one strong resonance in the main asteroid belt can deliver material into the inner Solar System within the short timescales suggested by dynamical models.  相似文献   
6.
Selective imprinting of gut-homing T cells by Peyer's patch dendritic cells   总被引:1,自引:0,他引:1  
Whereas naive T cells migrate only to secondary lymphoid organs, activation by antigen confers to T cells the ability to home to non-lymphoid sites. Activated effector/memory T cells migrate preferentially to tissues that are connected to the secondary lymphoid organs where antigen was first encountered. Thus, oral antigens induce effector/memory cells that express essential receptors for intestinal homing, namely the integrin alpha4beta7 and CCR9, the receptor for the gut-associated chemokine TECK/CCL25 (refs 6, 8, 9). Here we show that this imprinting of gut tropism is mediated by dendritic cells from Peyer's patches. Stimulation of CD8-expressing T cells by dendritic cells from Peyer's patches, peripheral lymph nodes and spleen induced equivalent activation markers and effector activity in T cells, but only Peyer's patch dendritic cells induced high levels of alpha4beta7, responsiveness to TECK and the ability to home to the small intestine. These findings establish that Peyer's patch dendritic cells imprint gut-homing specificity on T cells, and thus license effector/memory cells to access anatomical sites most likely to contain their cognate antigen.  相似文献   
7.
Lepidomeda albivallis (White River spinedace), a fish species endemic to the White River, Nevada, appeared headed toward extinction. In 1991 only 1 population remained, and it comprised fewer than 50 individuals in a 70-m stream reach. We monitored population recruitment and distribution and studied life history and habitat use from 1993 through 1998. We determined that L. albivallis was not reproducing and was continuing to decline, and as an emergency measure we relocated the population (14 in spring 1995 and 6 in spring 1996) downstream 200 m to a secure habitat that we judged more favorable for reproduction. The relocated population reproduced, and by September 1998 it had increased to 396 individuals that inhabited more than 1 km of stream including both pond and stream habitats. In streams they oriented near the bottom but frequently moved up in the water column to strike at drift items. Gut analysis of museum specimens indicated L. albivallis is omnivorous but feeds primarily upon aquatic invertebrates. Conservation of L. albivallis will require reestablishing additional populations within its former range.  相似文献   
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Zusammenfassung Erstmalig wurde radiochemisch reines59Fe (> 99,9999%) eingesetztg, um die radioaktive Halbwertzeit des59Fe mit 44,52±0,016 (¯m a ±SE) Tagen entsprechend einer Umwandlungskonstanten=0.015568±0.000 0056 [d–1] zu bestimmen. Radiochemisch reines59Fe wird im menschlichen Körper bei Männern mit einer Umsatzrate von 0,032%/Tag (=1,2 mg Fe/Tag) und bei menstruierenden Frauen mit 0,052%/Tag (=1,4 mg Fe/Tag) ausgeschieden. Diese Gesamtkörper-59Fe-Eliminationsrate entspricht dem Eisenbedarf des Menschen.  相似文献   
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