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21.
Zusammenfassung Die Verabereichung einer letalen Dosis Colchicin verursacht u. a. eine Zunahme der unveresterten Fettsäuren und eine Abnahme des Körpergewichts. Der Gehalt an veresterten Fettsäuren, freiem und verestertem Cholesterin und Plasmaeiweissen bleibt unverändert, ebenso Hämatokrit-und Hämoglobinwerte.

Supported by the National Heart Institute, Bethesda, Md.  相似文献   
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23.
提出了一种基于任意网络拓扑的分布式选举领导人算法。每一处理机既不知道系统的网络拓扑,也不知道系统中处理机的台数。对于由n台处理机组成的分布式系统,算法的消息复杂度最好为3#E,最坏不超过#E(2N+1)-N+n;对于同步分布式系统,其时间复杂度最好不超过3(n-1)△t,最坏不超过4(n-1)△t。  相似文献   
24.
提出了一种基于事务冲突图的并发控制方法.事务在执行前要提交其读集和写集,系统根据事务的读集和写集构造出一无圈的事务冲突图,并根据事务冲突图进行并发控制.这种并发控制方法具有对数据库无结构要求、无死锁、非两阶段等优点.讨论了其集中式并发控制方法和分布式并发控制方法.  相似文献   
25.
Spitzer NC 《Nature》2006,444(7120):707-712
The construction of the brain during embryonic development was thought to be largely independent of its electrical activity. In this view, proliferation, migration and differentiation of neurons are driven entirely by genetic programs and activity is important only at later stages in refinement of connections. However, recent findings demonstrate that activity plays essential roles in early development of the nervous system. Activity has similar roles in the incorporation of newly born neurons in the adult nervous system, suggesting that there are general rules underlying activity-dependent development. The extensive involvement of activity makes it likely that it is required at all developmental stages as a necessary partner with genetic programs.  相似文献   
26.
基于广义能量法的曲面光顺   总被引:9,自引:0,他引:9  
提出了同时考虑曲面几何及物理等多项光顺准则的基于广义能量法的曲面整体光顺思路,建立了包含曲面截线族粗光顺、曲面粗光顺两个步骤的曲面光顺方法,论述了曲面精光顺中广义能量表达式和约束条件的建立,实践证明,这种方法对于提高曲面的整体光顺性能具有良好的效果。  相似文献   
27.
When continents break apart, the rifting is sometimes accompanied by the production of large volumes of molten rock. The total melt volume, however, is uncertain, because only part of it has erupted at the surface. Furthermore, the cause of the magmatism is still disputed-specifically, whether or not it is due to increased mantle temperatures. We recorded deep-penetration normal-incidence and wide-angle seismic profiles across the Faroe and Hatton Bank volcanic margins in the northeast Atlantic. Here we show that near the Faroe Islands, for every 1 km along strike, 360-400 km(3) of basalt is extruded, while 540-600 km(3) is intruded into the continent-ocean transition. We find that lower-crustal intrusions are focused mainly into a narrow zone approximately 50 km wide on the transition, although extruded basalts flow more than 100 km from the rift. Seismic profiles show that the melt is intruded into the lower crust as sills, which cross-cut the continental fabric, rather than as an 'underplate' of 100 per cent melt, as has often been assumed. Evidence from the measured seismic velocities and from igneous thicknesses are consistent with the dominant control on melt production being increased mantle temperatures, with no requirement for either significant active small-scale mantle convection under the rift or the presence of fertile mantle at the time of continental break-up, as has previously been suggested for the North Atlantic Ocean.  相似文献   
28.
Summary The i.v. injection of bacterial endotoxin into dogs was found to cause a rapid increase in plasma levels of infused -aminoisobutyric acid. The findings suggest that nonmetabolic factors (tissue uptake, fluid shifts) influence amino acid distribution during endotoxemia.This investigation was supported in part by the Office of Naval Research, Contract N0001476CO132. R.E.K., Postdoctoral Fellow, supported by HL07090. Address correspondence to J.J.S.  相似文献   
29.
Autosomal dominant retinal vasculopathy with cerebral leukodystrophy is a microvascular endotheliopathy with middle-age onset. In nine families, we identified heterozygous C-terminal frameshift mutations in TREX1, which encodes a 3'-5' exonuclease. These truncated proteins retain exonuclease activity but lose normal perinuclear localization. These data have implications for the maintenance of vascular integrity in the degenerative cerebral microangiopathies leading to stroke and dementias.  相似文献   
30.
Résumé LeOHB, la concentration du14CO2 ainsi que l'activité specifique du14CO2 ont été determinées dans l'artère fémorale, le sinus sagittal supérieur et le liquid subarachnoïdal cortical. L'infusion duOHB enregistré a amené la présence de14CO2 dans le liquide subarachnoïdal cortical. Les résultats indiquent que leOHB du liquide cérébro spinal peut être oxydé par les tissus à proximité de l'espace subarachnoïdal cortical.  相似文献   
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