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81.
主要研究带钛合金连接头硼/铝复合材料管构件中B-Al-Ti间的界面结构与性质。研究表明,在复合工艺条件下,硼-铝界面附近没有检测到任何铝-硼化合物,而钛-铝间形成TiAl有序金属间化合物相。实验证明,硼/铝复合材料与铝合金端环之间采用的固结方法是有效的,且可按照受载类型随意调整斜面搭接长度,达到承受不同载荷的目的。 相似文献
82.
Role of macrophage overactivation in the development of acute pancreatic injury in rats 总被引:1,自引:0,他引:1
PURPOSE: To report quantitative changes in the anterior chamber configuration after small-incision cataract surgery with implantation of a posterior chamber intraocular lens by means of ultrasound biomicroscopy. METHODS: We examined the anterior chamber configuration of 20 eyes of 20 patients before and 3 months after small-incision cataract surgery (phacoemulsification and aspiration plus foldable intraocular lens implantation through a 3.0- to 4.0-mm self-sealing wound) by means of ultrasound biomicroscopy. The following variables were measured: the anterior chamber depth at the center of the cornea, the angle-opening distance 250 microns from the scleral spur (AOD250), the angle-opening distance 500 microns from the scleral spur (AOD500), and the trabecular-iris angle. RESULTS: The anterior chamber depth at the center of the cornea, AOD250, AOD500, and trabecular-iris angle increased significantly after surgery. The preoperative anterior chamber depth at the center of the cornea and trabecular-iris angle were negatively correlated with the differences between the postoperative and preoperative values (P < .01). The preoperative values of all variables examined were negatively correlated with the ratios of the postoperative value to the preoperative value (P < .002). CONCLUSIONS: The present results showed that small-incision cataract surgery significantly deepened the anterior chamber and widened its angle. The more shallow the preoperative anterior chamber was, the greater the postoperative change of the chamber was; and the more narrow the preoperative angle was, the greater the postoperative change of the angle was. 相似文献
83.
In a previous study we have demonstrated that endogenous neurotrophin 3 (NT3) is required for the survival of most sympathetic neurones in postnatal rats. However, the mechanisms underlying the action of NT3 on sympathetic neurones is not known. Neither is it understood whether NT3 is retrogradely transported from peripheral tissues or acts locally in an autocrine fashion. In the present study, NT3-mRNA was quantified in sympathetic effector tissues and NT3 protein was localized in intact and lesioned sympathetic nerves in rats. NT3-mRNA is expressed and developmentally regulated in many effector tissues including mesenteric arteries, salivary gland, heart and kidney but hardly detectable in the superior cervical ganglia of adult animals. The majority of sympathetic neurones express immunoreactivity for TrkA and TrkC in both neonatal and adult rats. Sympathetic somata are normally immunoreactive for NT3, but the immunoreactivity is abolished by systemic administration of NT3 antibodies or axotomy of postganglionic neurones, suggesting an accumulation of NT3 from extraneuronal sources. Furthermore, the detection of NT3-immunoreactivity in the internal carotid nerve as early as 3 h following a compression and only on the distal side indicates endogenous NT3 is retrogradely transported by sympathetic neurones. These studies provide evidence indicating that NT3, like nerve growth factor, is an effector tissue-derived neurotrophic factor for sympathetic neurones both during development and in the adult animal. Thus, we have provided a clear example that one type of neurone derives, through a retrograde transport mechanism, two neurotrophic factors simultaneously from its peripheral effector tissues. 相似文献
84.
PVDF中空纤维滤膜的形态结构 总被引:3,自引:0,他引:3
用L-S相转换法制备了聚偏氟乙烯(PVDF)中空纤维不对称滤膜。铸膜液由聚合物、溶剂和添加剂组成。用电子显微镜(SEM)考察了聚合物浓度、添加剂用量及种类对膜形态结构的影响。实验结果表明,聚合物浓度对膜形态结构有显著影响,当铸膜液中聚合物浓度较低时,无论用什么种类添加剂,都能形成大、且多的孔,但孔的形状随添加剂不同而异。当恒定聚合物浓度时,添加剂的用量对膜形态结构有很大的影响,但孔的大小及多少与添加剂含量的多少不成正比。 相似文献
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88.
C-VISION中文窗口系统综合采用了面向对象与窗口环境设计的程序方法,彻底更新了在微机上进行中文窗口设计的编程思想,同时作为一个基础系统,为软件设计节约了大量的人力和时间,实现了微机程序的共享。 相似文献
89.
本文针对整体式预热器U型管蒸汽发生器建立了热工数学模型并进行了动态模拟。该模型是一个25阶、非线性、可移动边界模型。包括:一、二次侧的质量与能量平衡方程以及确定二次侧下降段流量的动量守恒方程。对所建立的模型利用Gear方法作了蒸汽阀门开度阶跃10%的瞬态模拟,所得结果和国外所公布的结果吻合得很好。由此可见。本文所建立的模型可以为这种蒸汽发生器的设计、运行、控制提供理论依据。 相似文献
90.
OBJECTIVE: To evaluate the therapeutical mechanism of Bushen Shengxue Paste (BSSXP) on anemia. METHODS: Chronic renal failure induced anemia patients were treated with BSSXP, clinical manifestation, anemia and renal function as indicators were observed in patients. The erythropoietin (EPO) and inhibition of colony-forming unit-erythrocyte (CFU-E) in patients' serum were determined by CFU-E in vitro. RESULTS: The patients' symptoms, renal function and anemia were improved after administration with BSSXP 1-2 course. EPO in serum was slightly increased. The inhibition of CFU-E in patient's serum was significantly decreased. CONCLUSIONS: BSSXP could improve the anemia degree, its mechanism might be through clearing the inhibitor of CFU-E in serum. 相似文献