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151.
When several diagnostic procedures are performed on a patient, the probability of his having or not having a specific ailment will change as the result of each procedure is known. This paper describes how such a change is readily calculated using Bayes' theorem. Information theory is also used to find the increment in information from each successive test. Numerical estimates are made using data pertinent to lung X-ray examinations. Finally, some implications for diagnostic examinations in general are drawn.  相似文献   
152.
To determine the cause of the body weight loss during bed rest (BR), fluid balance and anthropometric measurements were taken from seven men (19-21 yr) during three 2-wk BR periods which were separated by 3-wk ambulatory recovery periods. Caloric intake was 3,073 +/- 155 (SD) kcal/day. During two of the three BR periods they performed supine isotonic exercise at 68% of VO2max on the ergometer for 1 h/day; or supine isometric exercise at 21% of maximal leg extension force for 1 min followed by a 1-min rest for 1 h/day. No prescribed exercise was given during the other BR period. During BR, body weight decreased slightly with no exercise (-0.43 kg, NS), but decreased significantly (P less than 0.05) by -0.91 kg with isometric and by -1.77 kg with isotonic exercise. About one-third of the weight reduction with isotonic exercise was due to fat loss (-0.69 kg) and, the remainder, to loss of lean body mass (-0.98 kg). It is concluded that the reduction in body weight during bed rest has two major components: First, a loss of lean body mass caused by assumption of the horizontal body position that is independent of the metabolic rate. Second, a loss of body fat content that is proportional to the metabolic rate.  相似文献   
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When baseline red blood cell catechol O-methyltransferase (COMT) was measured in 15 unipolar depressive women, the authors found a linear correlation between COMT and response to imipramine (best outcome occurring at low COMT). The results of this study were not related to such variables as intensity of depression, family history, or psychiatric history. The authors suggest that this assay may be useful either as a predictor of response to the drug or as a guide in choosing the optimum dose.  相似文献   
155.
Two patients who had cervical lymph node metastases as the first symptom of a localized soft tissue extramedullary plasmacytoma of the epiglottis and nasopharynx, respectively, are described. Classical multiple myeloma was excluded by bone marrow biopsies and x-ray studies of the skeleton. In both patients, the primary tumor was diagnosed 2 years after excision of the cervical lymph node. One patient had a IgD, lambda myeloma protein in the serum and excreted lambda Bence-Jones protein into the urine. No M-component was found in the other patient. Both are living with a long survival of 8 and 4 years respectively. The presence of a cervical lymph node plasmacytoma should suggest an upper respiratory tract or oropharynx plasmacytoma rather than a primary lymph node plasmacytoma.  相似文献   
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A major problem facing the dairy industry is the continued and consistent conversion of manufacturing grade milk to grade A, and the disproportionate effect of this on Class I utilization and, hence, on farm milk blend prices in the parts of the country where most of the grade B is located. Potential supplies of grade A milk are so concentrated and likely to convert to grade A in such substantial quantities that the problem is serious–far more so than in the past. New broader based pooling and pricing procedures which will stabilize interorder blend price relationships and at the same time preserve orderly marketing and deter uneconomic milk movements are needed. The likely economic results of such programs including standby pool, regional pools, national pools, flat Class I pricing and increased Class II prices are analyzed in this paper.  相似文献   
159.
Retrograde coronary artery flow was observed angiographically in 43 patients with aortic stenosis and/or regurgitation. In the 24 patients with pure or predominant aortic stenosis, retrograde flow was seen in all 24 during end-systole. In the eight patients with pure aortic regurgitation, retrograde flow was seen mainly during end-diastole (6/8). Among the 11 patients with stenosis and regurgitation, retrograde flow was both end-systolic and enddiastolic. Dominant left coronary arteries were seen in 13 patients; 13 showed retrograde flow in the dominant arteries. Dominant right coronary arteries were seen in 25 patients: all 25 showed retrograde flow equally in the right and left coronary. Five of the 43 patients could not be evaluated for dominance because of coronary artery occlusions. The severity of retrograde flow did not correlate with usual clinical, hemodynamic or tension-stress parameters: angina, electrocardiographic abnormality, end-diastolic pressure or volume, end-systolic pressure or volume, ejection fraction, severity of aortic regurgitation, peak or mean valve gradient, aortic valve area, myocardial tension and stress calculations, or DPTI:SPTI. In summary, retrograde coronary artery flow was seen in all 43 patients with severe aortic valve disease. The time in the cardiac cycle when retrograde flow occurred was related to the type of valve disease. Retrograde flow was seen mainly in the coronary arteries supplying the left ventricle and may result from increased regional myocardial stresses.  相似文献   
160.
With the Enviro-Chrom-Ex process it is possible to eliminate ecologically and economically hexavalent chromium (chromate) from water selectively. The process which is based on the principle of selective ion exchange works with different chromate concentrations and under the presence of other ions, irrespective of the water hardness. The values of water-offtake reach 0,1 mg CrVI/I at maximum, causing neither pH alteration nor concentration of the salt-content of the water. The plant which has been installed in the Holzimprägnierwerk AG, Waldkirch, Switzerland, for treating chromium-containing drainage-water permits the chromium-containing regenerates to be recycled into the impregnation process. Using this chromate-recycling-process, the harmful substance can be eliminated optimally.  相似文献   
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