UNIFICATION OF SYMBOLS AND DIAGRAMS     

White WP 《Science (New York, N.Y.)》1920,51(1322):436-437

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CROWN GALL PRODUCTION BY BACTERIA-FREE TUMOR TISSUES     

White PR  Braun AC 《Science (New York, N.Y.)》1941,94(2436):239-241

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Early origin and recent expansion of Plasmodium falciparum     

Joy DA  Feng X  Mu J  Furuya T  Chotivanich K  Krettli AU  Ho M  Wang A  White NJ  Suh E  Beerli P  Su XZ 《Science (New York, N.Y.)》2003,300(5617):318-321

The emergence of virulent Plasmodium falciparum in Africa within the past 6000 years as a result of a cascade of changes in human behavior and mosquito transmission has recently been hypothesized. Here, we provide genetic evidence for a sudden increase in the African malaria parasite population about 10,000 years ago, followed by migration to other regions on the basis of variation in 100 worldwide mitochondrial DNA sequences. However, both the world and some regional populations appear to be older (50,000 to 100,000 years old), suggesting an earlier wave of migration out of Africa, perhaps during the Pleistocene migration of human beings.  相似文献   

COMMITTEE ON DRUG ADDICTION OF THE NATIONAL RESEARCH COUNCIL     

White WC 《Science (New York, N.Y.)》1931,73(1882):97-98

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Conserved eukaryotic fusogens can fuse viral envelopes to cells     

Avinoam O  Fridman K  Valansi C  Abutbul I  Zeev-Ben-Mordehai T  Maurer UE  Sapir A  Danino D  Grünewald K  White JM  Podbilewicz B 《Science (New York, N.Y.)》2011,332(6029):589-592

Caenorhabditis elegans proteins AFF-1 and EFF-1 [C. elegans fusion family (CeFF) proteins] are essential for developmental cell-to-cell fusion and can merge insect cells. To study the structure and function of AFF-1, we constructed vesicular stomatitis virus (VSV) displaying AFF-1 on the viral envelope, substituting the native fusogen VSV glycoprotein. Electron microscopy and tomography revealed that AFF-1 formed distinct supercomplexes resembling pentameric and hexameric "flowers" on pseudoviruses. Viruses carrying AFF-1 infected mammalian cells only when CeFFs were on the target cell surface. Furthermore, we identified fusion family (FF) proteins within and beyond nematodes, and divergent members from the human parasitic nematode Trichinella spiralis and the chordate Branchiostoma floridae could also fuse mammalian cells. Thus, FF proteins are part of an ancient family of cellular fusogens that can promote fusion when expressed on a viral particle.  相似文献   

Global carbon sinks and their variability inferred from atmospheric O2 and delta13C   总被引：1，自引：0，他引：1  

Battle M  Bender ML  Tans PP  White JW  Ellis JT  Conway T  Francey RJ 《Science (New York, N.Y.)》2000,287(5462):2467-2470

Recent time-series measurements of atmospheric O2 show that the land biosphere and world oceans annually sequestered 1.4 +/- 0.8 and 2.0 +/- 0.6 gigatons of carbon, respectively, between mid-1991 and mid-1997. The rapid storage of carbon by the land biosphere from 1991 to 1997 contrasts with the 1980s, when the land biosphere was approximately neutral. Comparison with measurements of delta13CO2 implies an isotopic flux of 89 +/- 21 gigatons of carbon per mil per year, in agreement with model- and inventory-based estimates of this flux. Both the delta13C and the O2 data show significant interannual variability in carbon storage over the period of record. The general agreement of the independent estimates from O2 and delta13C is a robust signal of variable carbon uptake by both the land biosphere and the oceans.  相似文献   

Chromosome 17 deletions and p53 gene mutations in colorectal carcinomas   总被引：175，自引：0，他引：175  

S J Baker  E R Fearon  J M Nigro  S R Hamilton  A C Preisinger  J M Jessup  P vanTuinen  D H Ledbetter  D F Barker  Y Nakamura  R White  B Vogelstein 《Science (New York, N.Y.)》1989,244(4901):217-221

Previous studies have demonstrated that allelic deletions of the short arm of chromosome 17 occur in over 75% of colorectal carcinomas. Twenty chromosome 17p markers were used to localize the common region of deletion in these tumors to a region contained within bands 17p12 to 17p13.3. This region contains the gene for the transformation-associated protein p53. Southern and Northern blot hybridization experiments provided no evidence for gross alterations of the p53 gene or surrounding sequences. As a more rigorous test of the possibility that p53 was a target of the deletions, the p53 coding regions from two tumors were analyzed; these two tumors, like most colorectal carcinomas, had allelic deletions of chromosome 17p and expressed considerable amounts of p53 messenger RNA from the remaining allele. The remaining p53 allele was mutated in both tumors, with an alanine substituted for valine at codon 143 of one tumor and a histidine substituted for arginine at codon 175 of the second tumor. Both mutations occurred in a highly conserved region of the p53 gene that was previously found to be mutated in murine p53 oncogenes. The data suggest that p53 gene mutations may be involved in colorectal neoplasia, perhaps through inactivation of a tumor suppressor function of the wild-type p53 gene.  相似文献   

Differential effects of classical and atypical antipsychotic drugs on A9 and A10 dopamine neurons   总被引：10，自引：0，他引：10  

F J White  R Y Wang 《Science (New York, N.Y.)》1983,221(4615):1054-1057

Prolonged treatment with classical antipsychotic drugs decreased the number of spontaneously active dopamine neurons in both the substantia nigra (A9) and the ventral tegmental area (A10) of the rat brain. In contrast, treatment with atypical antipsychotic drugs selectively decreased the number of A10 dopamine neurons. Related drugs lacking antipsychotic efficacy failed to decrease dopamine activity. These findings suggest that the inability of atypical antipsychotic drugs to decrease A9 dopamine neuronal activity may be related to their lower potential for causing tardive dyskinesia and that the inactivation of A10 neurons may be involved in the delayed onset of therapeutic effects during treatment.  相似文献   

Acceleration of nitrogen ions to 7.4 gev in the princeton particle accelerator     

White MG  Isaila M  Prelec K  Allen HL 《Science (New York, N.Y.)》1971,174(4014):1121-1123

Nitrogen ions in charge states N(5+) and N(6+) have been accelerated in the Princeton Particle Accelerator to 4 and 7.4 billion electron volts (Gev), respectively. An external N(5+) beam of 1 x 10(6) particles per second has been obtained and focused to a 6-millimeter-diameter spot. The N(6+) beam was about 2 x 10(5) particles per second. The total charge-changing collision cross section of N(5+) in water vapor was determined as a function of ion energy. The improvement in vacuum necessary to increase the N(5+) beam at least tenfold was calculated. The N(6+) total cross section is probably smaller than that of N(5+) at the higher energies.  相似文献   

Stratigraphic interpretation of the omo shungura and lake turkana fossil suid record     

White TD  Harris JM 《Science (New York, N.Y.)》1978,202(4374):1309

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