Volatile N-nitrosamines in infant pacifiers sold in the United States as determined by gas chromatography/thermal energy analysis     

S M Billedeau  H C Thompson  B J Miller  M L Wind 《Journal of the Association of Official Analytical Chemists》1986,69(1):31-34

Volatile N-nitrosamines in infant latex rubber pacifiers were determined using a modification of a previously described dichloromethane extraction procedure, followed by gas chromatography/thermal energy analysis. Under an interagency agreement between the National Center for Toxicological Research and the Consumer Product Safety Commission (CPSC), data were obtained on the baseline and compliance concentrations of volatile N-nitrosamines in infant pacifiers sold in the United States. Pacifiers made by 18 different manufacturers before and after the January 1, 1984 action level of 60 ppb was set by the CPSC were analyzed for volatile N-nitrosamines. N-Nitrosodibutylamine was the principal N-nitrosamine found, along with trace amounts of N-nitrosodimethylamine, N-nitrosodiethylamine, and N-nitrosopiperidine. Mean total volatile N-nitrosamine levels for baseline and compliance samples were 63.9 and 21.2 ppb, respectively. The pacifier lots sampled after January 1, 1984 showed a significant decrease in contamination levels, indicating that at least 98% of the market share is in compliance with the CPSC enforcement policy for N-nitrosamines in infant pacifiers sold in the United States.  相似文献   

Effect of the herbicide prometryne [2,4-bis(isopropylamino)-6-(methlthio)-s-triazine] on mitochondria     

Thompson OC  Truelove B  Davis DE 《Journal of agricultural and food chemistry》1969,17(5):997-999

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Frame-shift deletions in patients with Duchenne and Becker muscular dystrophy   总被引：33，自引：0，他引：33  

S B Malhotra  K A Hart  H J Klamut  N S Thomas  S E Bodrug  A H Burghes  M Bobrow  P S Harper  M W Thompson  P N Ray 《Science (New York, N.Y.)》1988,242(4879):755-759

Duchenne muscular dystrophy (DMD) and its less severe form Becker muscular dystrophy (BMD) are allelic disorders. It has been suggested that in the mutations involving BMD, the translational reading frame of messenger RNA is maintained and a smaller, though partially functional, protein is produced. In order to test this, the exon-intron boundaries of the first ten exons of the DMD gene were determined, and 29 patients were analyzed. In a number of BMD patients (mild and severe BMD), the reading frame of messenger RNA was not maintained. On the basis of these findings, a model for reinitiation from an internal start codon is suggested.  相似文献   

Sex pheromones produced by male boll weevil: isolation, identification, and synthesis     

Tumlinson JH  Hardee DD  Gueldner RC  Thompson AC  Hedin PA  Minyard JP 《Science (New York, N.Y.)》1969,166(3908):1010-1012

The response of female boll weevils to males, Anthonomus grandis Boheman, in laboratory bioassays can be reproduced by exposure to a mixture of compounds I, II, and either III or IV, all isolated from male weevils and their fecal material. The same response was elicited by mixtures of tile synthesized coimpounds. Compound I is (+)-cis-2-isopropenyl-l-methylcyclobtutaneethanol; II, cis-3,3-dimethiyl->(1,beta)cyclohexaneethanol; III, cis-3,3-dimethlyl->(1,alpha)-cyclohexaneacetaldehyde; and IV, trans-3,3-dimethyl->(1,alpha)-cyclohexanecetaldehyde.  相似文献   

PERIPHERAL DISTRIBUTION OF FORELIMB NERVES IN AMBLYSTOMA     

Thompson JD 《Science (New York, N.Y.)》1936,84(2179):310-311

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UNIVERSITY AND EDUCATIONAL NOTES     

Thompson WG 《Science (New York, N.Y.)》1922,55(1410):18-19

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An ion balance for ultra-high-precision atomic mass measurements     

Rainville S  Thompson JK  Pritchard DE 《Science (New York, N.Y.)》2004,303(5656):334-338

We have developed the analog of a double-pan balance for determining the masses of single molecular ions from the ratio of their two cyclotron frequencies. By confining two different ions on the same magnetron orbit in a Penning trap, we balance out many sources of noise and error (such as fluctuations of the magnetic field). To minimize the systematic error associated with the Coulomb interaction between the two ions, they are kept about 1 millimeter apart from each other, resulting in fractional uncertainty below 1 x 10(-11). Such precision opens the door to numerous applications of mass spectrometry, including metrology, fundamental physics, and weighing chemical bonds.  相似文献   

THE EFFECTS OF ALTERNATING CURRENTS UPON CUTANEOUS SENSORY THRESHOLDS     

Thompson IM 《Science (New York, N.Y.)》1933,78(2021):268-269

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The role of magma overpressure in suppressing earthquakes and topography: worldwide examples     

Parsons T  Thompson GA 《Science (New York, N.Y.)》1991,253(5026):1399-1402

In an extending terrane basaltic magma supplied at a pressure greater than the least principal stress (overpressure) may be capable of suppressing normal faulting and the earthquakes and topographic relief that commonly accompany normal faulting. As vertical dikes intrude, they press against their walls in the direction opposite the least principal stress and increase its magnitude. The emplacement of tabular intrusions causes the internal magma pressure to act selectively in opposition to tectonic stresses. This process tends to equalize the stresses and thus diminishes the deviatoric stress (difference between maximum and minimum stresses) that creates faults and causes earthquakes. Observations of the pattern of seismicity and magmatism worldwide indicate that magmatism commonly supplants large earthquakes as the primary mechanism for accommodating tectonic extension. Recognizing the extent of magmatic stress accommodation is important in assessing seismic and volcanic risks.  相似文献   

THE CANONS OF COMPARATIVE ANATOMY     

Thompson WP 《Science (New York, N.Y.)》1918,48(1241):371

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