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81.
82.
Expressions used in the calculation of nonrelativistic K-shell cross sections for direct Coulomb ionization in the plane-wave Born approximation have been numerically integrated and tabulated for a range of projectile velocities and target binding-energy parameters which extends beyond that found in previous tables. The extended range of these parameters has been dictated by the need to apply subsequent developments in the basic theory to new heavy-ion data. The new table is intended to replace the others and is cast in terms of universal quantities. Analytical limiting forms are provided for use outside the region defined by the table. 相似文献
83.
The average gastrointestinal uptake 4 h after an intragastric dose of 400 nmol of cadmium chloride labeled with 109CdCl2 in iron-deficient mice, 25%, was significantly greater than the result, 16%, in iron-normal animals, and more cadmium entered the body of the former, 3.8%, than the latter, 2% (P less than 0.05). Between 4 and 72 h, gastrointestinal radioactivity declined without further increase in body activity; however, more radiocadmium remained in the duodenum of iron-deficient than iron-normal animals (P less than 0.05). The radiocadmium sequestered in the duodenum was bound to a protein with a molecular weight of about 12,000. After subcutaneous injection of radiocadmium, the rate of excretion of radioactivity from the body was similar in iron-normal and iron-deficient mice; however, a greater proportion of the injected dose accumulated in the duodenum of the iron-deficient animals (P less than 0.05). Thus, the intestinal adapative response to iron deficiency may enhance cadmium toxicity, whereas sequestration and subsequent excretion of cadmium by the intestinal mucosa serves to protect the body against toxic effects. The duodenum, particularly in iron-deficient mice, is especially vulnerable to the toxic effects of cadmium. 相似文献
84.
Don McDaniel 《IIE Transactions》1977,9(1):82-87
This paper presents an automated approach to the design of bulk cushioning systems. The developed code can be utilized in package and shipping container design, and other impact absorption applications. A model of impact response is developed and its validity demonstrated through statistical testing. The model is then used as the objective program for a sequential search procedure that searches out the best cushion design. 相似文献
85.
Lateral diffusion in planar lipid bilayers 总被引:1,自引:0,他引:1
PF Fahey DE Koppel LS Barak DE Wolf EL Elson WW Webb 《Canadian Metallurgical Quarterly》1977,195(4275):305-306
Direct measurements by fluorescence correlation spectroscopy of lateral diffusion coefficients of fluorescent lipid analogs in lipid bilaryer membranes indicate self-diffusion coefficients D greater than 10(-7) square centimeters per second for various lipid systems above their reported transition temperatures. Cholesterol in egg lecithin at mole ratio of 1 : 2 reduces D by about twofold, while retained hydrocarbon solvent can increase it by two- to threefold. 相似文献
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RM Silver JH Warrick MB Kinsella LS Staudt MH Baumann C Strange 《Canadian Metallurgical Quarterly》1993,20(5):838-844
Fourteen patients with systemic sclerosis (SSc, scleroderma) and interstitial lung disease were treated with oral cyclophosphamide (1-2 mg/kg/day) and low dose prednisone (< 10 mg/day). There was a significant improvement in FVC after 6 months compared to entry values (2.21 +/- 0.19 l vs. 2.03 +/- 0.15 l, p < 0.02). Improvement was maintained at 12 months (2.27 +/- 0.27 l, p < 0.05) and 18-24 months (2.60 +/- 0.28 l, p < 0.001). In 12 cases followed for 18-24 months, FVC was stable or improved. No significant improvement or decline was noted for the DLCO. Side effects included cytopenia (2), infection (1), and hemorrhagic cystitis (2), and one possible related malignancy. A controlled prospective trial of cyclophosphamide is warranted in patients with SSc and active interstitial lung disease. 相似文献
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