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The intradural sagittal diameter at the second cervical vertebra (SD/C2) of 62 SIDS cases was measured myelographically. This SD/C2 proved to be dependent on body size, body weight, and age. A clear, age-dependent difference is to be found in the primarily narrow spinal canal. This parameter (SD/C2), which is more precisely defined in adults on the basis of clinical, radiological, and autopsical findings is assumed to have the value of 0.5 cm in the first 2 months, 0.6 cm in the third month, and 0.65 cm in the fourth month. The resulting potential danger to infants is dependent upon their position. The SD/C2, was significantly decreased in extension as compared to a neutral posture. With consideration of the primarily narrow spinal canal in the infant, there is, according to our measurements, a potential hazard for the infant in any further, significant shortening of the SD/C2. This is independent of the width of the spinal canal under maximal extension. We found individual cases in which the SD/C2 was decreased by almost 50% from the normal value in neutral position. No correlation was found between the primary width of the spinal canal and the degree of luminal reduction upon extension.  相似文献   
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This paper presents an econometric analysis of the impact of collaboration with universities on the innovative output of firms. We also illustrate the differences that emerge from robustness checks, based on different matching estimators and samples. Our findings strongly suggest that university collaboration has a positive influence on the innovative activity of large manufacturing firms. In contrast, there appears to be an insignificant association between university collaboration and the average service firm’s innovation output.  相似文献   
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The demise of the USSR led to the collapse of its centrally organised retail system. With this collapse the supply of consumer goods dried up, especially in the remote parts of the former USSR. At the same time the advent of capitalism offered a new institutional framework for independent retail activities. In the Kyrgyz Republic, where the economic liberalisation followed strictly the Washington Consensus, a large number of small shops emerged in both urban and rural areas. This study analyses the reasons for this boom in retail start-ups as well as the constraints the mainly inexperienced merchants encounter. As will be shown, any success in retail activities depends greatly on the performance of other economic sectors. The main goal of starting a retail business is to minimize risks within the overall livelihood strategies of households in rural Kyrgyzstan.  相似文献   
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Abstract

The units and books on this list are among those we most highly recommend for classroom use. These materials focus on China's socio-political history.  相似文献   
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