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621.
The value for identification purposes of the radiographic frontal sinus outline, which is unique to each individual and remains constant throughout that individual's lifetime, is discussed. A general discussion of identification using frontal sinus X-rays is presented, along with four cases.  相似文献   
622.
The period under review in this chronicle—December 1980 to mid-August 1981—was, like 1980, characterized by relative political and administrative stability and consolidation. Such a climate of stability was, of course, to be expected as the system instituted with self-government was newly established and refined. Moreover, most of the election pledges which involved significant administrative implications had been implemented in the first months of the Third Assembly. If any major alteration to administrative structure or process is to occur (and there is no present indication of such intention by the government), it is likely to take place after the budget session in August.  相似文献   
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The Age Discrimination in Employment Act (ADEA) was amended in 1978 to prohibit mandatory retirement before age 70 in most occupations. The impact of this legislation on the probability of older persons remaining in the labor force is the primary concern of this article. Specifically, questions concerning which older workers are affected by mandatory-retirement provisions and the extent to which they are forced to retire and leave the labor force are examined. Tabular analysis of data from the Retirement History Study on persons aged 62-63 in 1969 shows significant variation in mandatory-retirement coverage between the public and private sectors and across industries, occupations, and demographic groups. Until age 65, the labor-force participation rate of those facing compulsory retirement is higher than or equal to that of those not covered but it drops significantly below the noncovered rate after 65. Logit analysis of the labor-force participation of persons before and after age 65 indicates that mandatory retirement at that age reduces the probability of retirement by approximately 16.7 percentage points for white men wage earners. This results in a decline in the labor-force participation rate of all men aged 66-67 of approximately 4 percentage points.  相似文献   
630.
The high-performance liquid chromatographic resolution of the enantiomers of amphetamine, methamphetamine, ephedrine, and pseudoephedrine is described. The sugar isothiocyanate, 2,3,4,6-tetra-O-acetyl-beta-D-glucopyranosyl isothiocyanate (GITC), is used as a chiral derivatizing agent, with chromatographic separations of the diastereomers formed with each amine made using a standard achiral C18 stationary phase.  相似文献   
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