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31.
32.
The relationship of a member of the transmembrane dystrophin-associated glycoprotein (DAG) complex to acetylcholine receptors (AChRs) was investigated using immunofluorescence techniques at rat neuromuscular junctions (NMJs) viewed en face. These results were compared with those from a similar previous study of dystrophin and an autosomal homologue (utrophin or dystrophin-related protein, DRP) (Bewick et al. Neuro Report 1992; 3: 857-860). The region of highest 43 K DAG (43DAG) labelling projected beyond the AChRs by approximately 0.3 microns, as does that for dystrophin. By contrast DRP labelling precisely co-localizes with the AChRs. These results suggest that at the NMJ, the region of high 43DAG concentration encompasses the area of highest intensity labelling for both DRP and dystrophin.  相似文献   
33.
We compared the data from four growth hormone (GH) immunoassays for analyzing 24-h GH profiles in four apparently normal subjects and four obese subjects (508 serum samples). The detection limit was 0.02 microgram/L for one immunochemiluminometric assay (ICMA), 0.1 microgram/L for two IRMAs, and 0.4 microgram/L for one RIA. All GH pulses with a peak ICMA value > 1 microgram/L were detected by each of the other methods. Overall, the correlation coefficient between the values obtained with all four assays exceeded 0.90. However, for GH concentrations < or = 0.25 microgram/L, acceptable concordance (r2 > or = 0.80) was reached only between the ICMA and one IRMA; between the ICMA and the RIA, concordance was acceptable only for GH concentrations > or = 10 micrograms/L. In the normal subjects, the percentage of undetectable values was 0% with the ICMA but 29% with one of the IRMAs; in obese subjects, the corresponding values were 12% and 38%.  相似文献   
34.
Studied in the course of one-stage epidemiologic survey of 1191 individuals were the threshold of gustatory sensitivity to table salt and nycterine natriuresis, relation of these indices to dietary habits, some risk factors for cardiovascular disorders and clinical parameters. Differing relations were established between gustatory sensitivity to table salt and natriuresis and age and gender of the examinees, the level of blood pressure, aggravated heredity in respect of arterial hypertension, smoking and alcohol abuse, this enabling one to embark upon a differential approach to dietetic correction of salt consumption.  相似文献   
35.
静电复印机是常用的办公设备,复印时要将不同规格的复印纸装入纸盒,经常需要操作者对纸盒进行调整。从使用者的角度讲,要用最小的力气、最简便的方法来完成对机器的操纵。这就需要考虑进行人性化设计。纸盒调整主要有自动监测纸盒尺寸的功能和纸盒内侧挡板(导纸板)的调整。对比不同品牌和不同机型复印机的纸盒设计,可看出人性化设计对方便操作者使用的重要性,也为购买机器时提供了借鉴。  相似文献   
36.
曹娥江大闸是国内最大的河口大闸,其中闸墩施工在夏季高温季节进行.较全面地阐述了混凝土原材料取料温度值的选取及控制措施,已浇筑混凝土内外温差及降温速率的控制措施等.根据闸墩的结构及边界条件,为了控制温度应力防止裂缝的产生,在施工过程中采取了骨料预冷、冷水拌和、掺冰屑拌和、仓面遮阳、内部通冷却水及外侧保温等综合温控措施,确保了闸墩混凝土的施工质量.  相似文献   
37.
The current study aims to provide fundamental insight into the behavior of microstructures containing grain sizes that span multiple length scales. A commercial 5083 Al alloy was selected as the material of interest to facilitate comparison with recently published data. The materials studied here were prepared via the thermal consolidation of powders that were cryomilled for different times (i.e., 0, 2, 4, and 8 hours). Following consolidation, the resultant microstructure was characterized by an equiaxed grain morphology with a size distribution centered around 200∼300 nm. Dispersed among the 200- to 300-nm grains were coarse-grained regions or ligaments with a grain size ranging from 600 nm to 2 μm. The occurrence of coarse-grained regions is rationalized on the basis of recrystallization or subgrain coarsening, whereas the occurrence of equiaxed fine regions is proposed to be a result of continuous grain growth. Two types of microstructures were selected for study, containing coarse-grained volumes of approximately 28 pct and 43 pct that corresponded to an ultimate tensile strength (UTS) of 566 MPa and 535 MPa, and a fracture strain of 3.2 pct and 3.5 pct, respectively. The observed ductility and the relevant toughening mechanisms were discussed in light of the presence of multiple length scales.  相似文献   
38.
路43-P1水平井高密度钻井液难点技术的解决   总被引:1,自引:0,他引:1  
路43-P1井是冀中坳陷饶阳凹陷留西油田路43断块施工难度较大的一口水平井。该井上部地层泥岩吸水膨胀造浆性强;下部地层局部存在异常高温,泥岩水敏性强,易吸水膨胀,造成地层坍塌。采用高密度钻井液钻井满足了井下要求,避免了井漏,减少了复杂情况的发生,缩短了建井周期;解决了深部定向、井温高、地层压力大、地层易垮塌的问题,顺利地完成了钻井目的。  相似文献   
39.
移动通信基站在高层建筑天台架设的定向天线,对周围环境的电磁辐射影响水平的监测进行分析,探讨高层建筑天台电磁辐射环境的污染防治对策。  相似文献   
40.
Livedo racemosa with cerebrovascular lesions has been described as Ehrmann-Sneddon syndrome. The etiopathogenetic factors provoking the vascular lesions, however, are of high diversity reaching from mechanical to autoimmune causes. We present a male patient with typical livedo racemosa, muscle pain and feeling of coldness of the forearms. By dermatohistopathology and magnetic resonance tomography of the brain, Ehrmann-Sneddon syndrome could be confirmed. At this time a chronic streptococcal infection could be diagnosed. Antibiotics, anticoagulants and vascularity-supplying therapy improved the clinical and subjective symptoms. Six months later, the patient developed dizziness, vision disorder, hypesthesia of the right forehead, malaise and weight loss. A further diagnostic workup including echocardiography revealed a myxoma of the left atrium. This report illustrates the association of Ehrmann-Sneddon syndrome with cardiac myxoma and points out that cardiac diagnostic examination should be included when dealing with small-vessel involvement of the brain.  相似文献   
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