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871.
R. C. Hamilton J. Bennet D. Drane E. Pietrzykowski F. Seddon A. Stefancic J. Cox 《Micron (Oxford, England : 1993)》1994,25(6):613-615
The state of fimbriae type 2 (Fim 2) and fimbriae type 3 (Fim 3) preparations from Bordetella pertussis were examined by negative stain electron microscopy. Uranyl acetate induced clumping of Fim 3 regardless of pH and was unsuitable as a stain for establishing the state of fimbriae. Both ammonium molybdate and sodium phosphotungstate were able to show the differences in Fim 3 stored at pH 7.2 and pH 9.5. 相似文献
872.
A E James C L Partain R J Hamilton S Baum M Silbiger T Greeson J C Gore 《Magnetic resonance imaging》1987,5(1):71-75
A significant proportion of MRI units are being installed in MRI Centers that are free standing enterprises offering outpatient diagnoses separate from hospitals. The development of such Centers represents a challenge to more traditional arrangements and may have serious implications for physician responsibility that depend on their management and administration. In this review several legal and ethical issues arising from the proliferation of such Centers are analyzed and it is argued that regulatory attitudes may need to be altered to avoid major shifts of emphasis in the pattern of use of high cost imaging equipment. 相似文献
873.
A. F. Kluk D. Krmpotic J. H. Hamilton J. J. Pinajian 《Zeitschrift für Physik A Hadrons and Nuclei》1970,235(5):391-394
TheK conversion coefficients of the 388 and 483 keV transitions in87Sr populated in the decay of87Y have been measured with Ge(Li) and Si(Li) detectors by the NPG method. We find α K values of 0.162 ± 0.010 and 0.00260 ± 0.00013 for the 388 and 483 keV transitions, respectively. 相似文献
874.
875.
J. K. Deng J. H. Hamilton A. V. Ramayya W. C. Ma X. W. Zhao J. Kormicki N. Severijns L. Vanneste W. D. Hamilton P. F. Mantica Jr. H. K. Carter 《Hyperfine Interactions》1992,75(1-4):439-445
On-line nuclear orientation was performed on70As. Anisotropy data have been obtained at 8.7mK for 29 gamma transitions. Multipole mixing ratios have been extracted for
17 transitions. Our results are in good agreement with existing data for the ten previously measured transitions. Our first
time data for the 1496 keV, 2+→2+ γ-ray suggest the 2536 keV level is a good candidate for a mixed symmetry level. 相似文献
876.
877.
Z. Grabowski J. E. Thun M. S. El-Nesr W. D. Hamilton 《Zeitschrift für Physik A Hadrons and Nuclei》1962,167(1):111-122
The study of nuclear structure effects in internal conversion has been extended to the Tm169 nucleus. Gamma-gamma, electron-gamma and gamma-electron directional correlations of the 177 keV-131 keV and the 198 keV-110 keV cascades have been measured. The following results were obtained:
$$\begin{array}{l} A_2 (177\gamma - 131\gamma ) = + 0 \cdot 275 \pm 0 \cdot 007,A_4 (177\gamma - 131\gamma ) = - 0 \cdot 005 \pm 0 \cdot 016, \\ A_2 (177\gamma - 131\gamma ) = + 0 \cdot 002 \pm 0 \cdot 007, \\ A_2 (177\gamma - 131K) = + 0 \cdot 497 \pm 0 \cdot 010, \\ A_2 (198\gamma - 110\gamma ) = + 0 \cdot 295 \pm 0 \cdot 007,A_4 (198\gamma - 110\gamma ) = - 0 \cdot 013 \pm 0 \cdot 017, \\ A_2 (198K - 110\gamma ) = + 0 \cdot 001 \pm 0 \cdot 008, \\ A_2 (198\gamma - 110K) = - 0 \cdot 005 \pm 0 \cdot 006. \\ \end{array}$$ 相似文献
878.
D. H. Hamilton 《Journal d'Analyse Mathématique》1990,55(1):40-50
This research is supported in part by NSF DMS-8700627. 相似文献
879.
Robert W. Hamilton 《Journal of heterocyclic chemistry》1976,13(3):545-553
A series of tricyclic pyrazoles were prepared from intermediates available from steroid total synthesis and tested for antiarrhythmic and antiinflammatory activity. 相似文献
880.