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121.
Opitz-Kaveggia syndrome (also known as FG syndrome) is an X-linked disorder characterized by mental retardation, relative macrocephaly, hypotonia and constipation. We report here that the original family for whom the condition is named and five other families have a recurrent mutation (2881C>T, leading to R961W) in MED12 (also called TRAP230 or HOPA), a gene located at Xq13 that functions as a thyroid receptor-associated protein in the Mediator complex.  相似文献   
122.
Information processing along the course of a visual interneuron.   总被引:1,自引:0,他引:1  
Locust ocellar retinal cells are innervated by giant second order cells, 2 mm long, which show discrete zones of integration along their course, including a major zone in the axonal length of the neuron. The complex synaptic arrangements which exist between higher-order afferent and efferent cells and these second order cells along their course suggests that transmission takes place by the electrotonic spread of slow potentials. The size and accessibility of these visual interneurons offers a unique preparation for examining mechanisms of graded synaptic transmission.  相似文献   
123.
New Giemsa method for the differential staining of sister chromatids   总被引:127,自引:0,他引:127  
P Perry  S Wolff 《Nature》1974,251(5471):156-158
  相似文献   
124.
在乱堆θ环不锈钢填料的自制填料塔中,使用单乙醇胺(MEA)作为吸收剂,研究MEA脱除CO2的去除率和总体积传质系数KGav,考察了贫液中CO2负载量、吸收剂浓度、液体流量、吸收温度等不同参数对总体积传质系数的影响.实验结果表明,KGav随贫液中CO2负载量的增大而减小,随吸收剂浓度、液体流量的增大而增大;且进料温度在3...  相似文献   
125.
ATransportProtocolandItsFormalDescriptionforLocalNetworksLiLayuanWuhanTransportationUniversity,430063,P.R.China(ReceivedMay4...  相似文献   
126.
Erratum to: J Syst Sci Syst EngDOI: 10.1007/s11518-007-5058-2The presentation of Table 2 in the original version of this article contained a few typos. The corrected Table 2 is given below.  相似文献   
127.
<正> This paper shows how the so called von Karman model can be obtained as a singular limitof a modified Mindlin-Timoshenko system when the modulus of elasticity in shear k tends to infinity,provided a regularizing term through a fourth order dispersive operator is added.Introducing dampingmechanisms,the authors also show that the energy of solutions for this modified Mindlin-Timoshenkosystem decays exponentially,uniformly with respect to the parameter k.As k→∞,the authors obtainthe damped von Karman model with associated energy exponentially decaying to zero as well.  相似文献   
128.
This paper considers a problem of optimal preventive maintenance and replacement schedule of equipment devoted to extracting resources from known deposits. Typical examples are oil drills, mine shovels, etc. At most one replacement of the existing machinery by a new one is allowed. The problem is formulated as an optimal control problem subject to the state constraint that the remaining deposit at any given time is nonnegative. We show that the optimal preventive maintenance, production rates, and the replacement and salvage times of the existing machinery and the new one, if required, can be obtained by solving sequentially a series of free-end-point optimal control problems. Moreover, an algorithm based on this result is developed and used to solve two illustrative examples.  相似文献   
129.
Family change, when adults depart or arrive around children, raises policy issues. Its measurement depends upon the evidence collected and from whom. This paper compares British children's histories obtained from fathers and mothers. The evidence, on one birth cohort of parents, comes from two sources: the National Child Development Study and the ONS Longitudinal Study. The resulting account of family change is not substantially different between parents. There is some under-reporting of children not living with their fathers. This is due to under-reporting by those included in the studies and to under-representation in them of absent fathers and lone parents.  相似文献   
130.
This article provides an account of first-person action research used for organization development in an all-volunteer professional organization. During a 12-month period, members sought to build a collaborative community out of a formerly defunct group. As part of this project, the group’s leader conducted a self-study by examining his role in exercising power while leading the group in building a collaborative community. Although the goals to collaborate and explore power relations originate in different philosophical perspectives, they were combined with moderate success in this project. An ongoing theoretical analysis of the challenges in using this approach illustrates the complications of combining collaborative approaches with the exploration of power.  相似文献   
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