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排序方式: 共有2412条查询结果,搜索用时 15 毫秒
991.
992.
NE Reich FE Seidelmann RR Tubbs WJ Mac Intyre TF Meaney RJ Alfidi RG Pepe 《Canadian Metallurgical Quarterly》1976,127(4):593-594
The usefulness and accuracy of CT scanning in the determination of bone mineral content is studied. The radius in 31 patients of both sexes and varying ages was examined using both the Norland-Cameron bone mineral analyzer and the CT scanner. There was reasonably good correlation (r=.72). Ten cadaver bones were then examined with CT scanning and were sent to the laboratory for calcium determination. These results indicate excellent correlation (r=.97). It is concluded that CT scanning represents the only practical and accurate in vivo method of bone mineral content determination. 相似文献
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994.
CA Dasher BI Hirschowitz JG Spenney RG Gibson AA Mihas 《Canadian Metallurgical Quarterly》1977,70(8):968-9, 973
Serum bile acid levels were determined by a radioimmunoassay for conjugates of cholic acid in 18 patients with biopsy-proved cirrhosis and compared to results of conventional liver function tests. Serum bile acid levels were abnormal in all 18 patients whereas results of the other tests were abnormal in only 50% to 72% of patients. In this group of patients with a well established diagnosis of cirrhosis, serum bile acid levels were a more sensitive indicator of liver dysfunction than standard liver function tests. 相似文献
995.
This study was undertaken to determine whether the increase in plasma glucagon concentration that occurs in response to prolonged exercise is modified by endurance exercise training. Eight subjects participated in an exercise program, consisting of running and bicycling, 4 days/wk for 10 wk. The training program resulted in an average increase in VO2 max of 18%. The average increase in plasma glucagon during a 60-min long bicycle exercise test that required 60% of the subjects' VO2 max was 107+/-28 pg/ml, from 116+/-14 pg/ml at rest to 223+/-37 pg/ml after 60 min of exercise, prior to training. After training the same absolute work rate resulted in an increase in plasma glucagon of only 20+/-6 pg/ml, from 125+/-20 to 145+/-16 pg/ml (P less than 0.02). A similar blunting of the glucagon response to exercise was seen during work of the same relative intensity after training. Plasma insulin concentration decreased from 18.1+/-2.5 to 7.6+/-1.6 muunits/ml during the 60 min of exercise before training. A similar decrease in insulin concentration was seen at the same relative work rate after training. However, the decrease in plasma insulin at the same absolute work rate, from 18.5+/-3.0 to 12.5+/-1.8 muunits/ml, was significantly smaller after training (P less than 0.05). 相似文献
996.
Norman E. Pawlowski Joseph E. Nixon R. O. Sinnhuber 《Journal of the American Oil Chemists' Society》1972,49(6):387-392
Nuclear magnetic resonance (NMR) method for the quantitative analysis of cyclopropenoid fatty acids (CPFA) in lipids is described.
Good accuracy is obtained at CPFA concentrations of 1% to 100%. At a CPFA concentration of 10%, NMR is accurate to 0.5%. The
position of absorption of the two ring methylene hydrogens is solvent dependent. 相似文献
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