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1.
文中介绍了智能仪表火灾报警仪良好的人机交互界面.阐述了智能仪表时间设置功能和时间显示功能.叙述了智能仪表系统初始化功能.对液晶显示器的显示地址排列进行了说明.对显示程序基本思路和屏幕显示方式进行了分析.研究了数据输入与编辑时光标闪烁功能,说明了程序设计方法.提出了菜单管理功能程序设计思路与实现方法.  相似文献   

2.
分析了数字化工厂产生的背景及其内涵.基于数字化工厂协作平台的概念模型,构建了平台的体系结构.基于组件库的管理思想,设计了离散型制造企业模型资源库的开发流程.具体介绍了数字化工厂平台中各个模块的功能和实施流程.提出了数字化工厂平台建设中需解决的关键问题.  相似文献   

3.
本文介绍了分析规模超临界萃取装置限流器的发展趋势,并详细介绍了一种新型限流器的设计.该限流器通过给阀体控温加热.彻底解决了超临界萃取中的冰堵问题.限流器采用两组阀结构,延长了限流器的使用寿命.  相似文献   

4.
试验状态及P.S.P.的特性依照图示2所示程序,S.S.P.已经可以得到了。表1给出了示于图2的符号定义。即  相似文献   

5.
混流生产车间布局研究   总被引:1,自引:0,他引:1  
总结了车间布局的一般原则.提出了矩阵运算方法判断混流生产线上各工序的关系,并判断工序冲突的存在.提出了处理工序冲突的方法.定义了混流生产线的工序时间,节拍以及工作地时间.结合流水线平衡方法,得出了使混流生产线平衡的方法.根据混流生产的特殊性,提出了混流生产车间布局的方法.  相似文献   

6.
动臂式塔式起重机变倍率装置的设计   总被引:2,自引:0,他引:2  
简述了动臂QT900塔机的变倍率原理,根据变倍率要求设计两种方案.并分析其合理性和探讨对结构的影响.经过比较,第二种变倍率方案经过施工检验.获得了更好的效果.实现了变倍率的功能,并提高了整机性能.  相似文献   

7.
闫伟  尹松  杜劲 《机械工程师》2007,(3):111-112
简述了抽油机的发展历程,分析了各阶段抽油机的特点及存在的问题.同时结合现阶段油田生产的特点,分析了节能抽油机的发展趋势.从一个新的角度分析了抽油机节能改进的方向.提出了"一机双井"的工作模式,做了简单的定性分析.  相似文献   

8.
给出了一种新型的二极管芯片分拣方案及其设备设计方案.从理论角度论证了其可行性.详细的论述了方案的运行过程.并通过理论推算给出了设备主要工艺参数的求取公式.经实验,此方案及给出的参数求取方法完全可行.  相似文献   

9.
汽车发动机振动主动控制试验研究   总被引:2,自引:1,他引:1  
为实现发动机振动的主动控制,建立了神经网络自适应控制模型.应用XPC目标构建了发动机振动自适应实时主动控制的硬件在环系统并进行了实车试验.分析了系统的控制效果,验证了控制器的跟踪性能.试验表明.应用神经网络自适应主动控制方法可以较好地控制发动机的振动.  相似文献   

10.
设计了用于秀丽线虫自动筛选的真空微夹控制系统.该系统主要由气路压力测量模块、气路压力控制模块、电磁开关阀控制模块等组成.阐述了各个功能模块的工作原理、硬件结构设计.介绍了系统软件的设计方法和工作流程.研制了实验样机,进行了实验,可以实现指定的吸附动作.  相似文献   

11.
Apoptotic cell death is common in the inflamed gastric mucosa, but its role in the regulation of cell homeostasis in normal gastric mucosa is unknown. We investigated the expression of CD95, Bcl-2, and Bax and their roles in the regulation of apoptosis in normal rat gastric mucosa and in cultures of highly enriched rat chief and parietal cells by immunostaining, Western blotting, and FACS. In intact tissue CD95, Bcl-2, and Bax were localized predominantly in the glandular base region in chief cells. In freshly isolated cells, expression of CD95, Bcl-2, and Bax was much more pronounced in chief cells than in parietal cells. A lower intracellular Bcl-2/Bax ratio suggesting a higher susceptibility to apoptosis was noticed in chief rather than in parietal cells. In extended cultures of parietal and chief cells, Bax expression was upregulated and Bcl-2 expression was downregulated. These regulatory changes, presumably caused by in vitro effects, were not associated with an increase in spontaneous apoptosis. Treatment of chief and parietal cells with Fas-ligand induced apoptosis of all CD95 expressing cells. Expression of CD95, Bcl-2, and Bax predominantly in chief cells suggests that in this cell type regulation of apoptosis may differ from that in parietal cells. Binding of FasL with functionally active CD95 receptors on chief and parietal cells may be relevant for induction of apoptosis in inflamed gastric mucosa.  相似文献   

12.
13.
The interaction of antimesometrial decidual cells and collagen fibrils was studied by light microscopy and ultrastructural cytochemistry in fed and acutely fasted mice on days 9-11 of pregnancy. Fibrillar elements in the extracellular space consisted of collagen fibrils and filamentous aggregates (disintegrating collagen fibrils). Intracellular vacuoles exhibited typical collagen immersed in electron-translucent material (clear vacuoles) and faint cross-banded collagen immersed in electron-opaque material (dark vacuoles). Fibrillar elements showed extracellular acid phosphatase activity which was stronger in the region of mature decidua than in predecidual cells region in all animals; it was conspicuous in mature decidua of fasted animals. Intracellular acid phosphatase activity was observed in dark vacuoles and lysosomes, and was absent in clear vacuoles in all cells studied. Since acid phosphatase activity reflects the presence of lysosomal hydrolases in general, the results indicate that breakdown of extracellular collagen occurs by release of lysosomal enzymes by decidual cells and also by internalization of collagen for intracellular degradation in fed and fasted mice. Collagen breakdown may be part of the process of tissue remodeling in mature and predecidual regions, however, in mature decidua, collagen breakdown is enhanced and may therefore contribute to nutrition of the fetus, specially in acutely fasted mice.  相似文献   

14.
Local dry mass concentrations of intracellular compartments in rat heart muscle and liver cells were estimated by quantitative electron microscopy and X-ray microanalysis of ultrathin frozen-dried cryosections. The results were used to calculate elemental concentrations per litre of compartment water from the X-ray microanalytical data. Water fractions were between 80.3 ± 1.3% of wet weight in the decondensed chromatin and only 45.1 ± 1.7% in mitochondria of liver cells. The lowest water fraction in heart muscle cells was also found in mitochondria. The ionic concentrations found in the cytoplasm of liver cells and in the myofibrils are in accord with the electroneutrality rule and in osmotic equilibrium with the extracellular concentrations. The concentrations of Na, K, Cl and P both in the cytoplasm and in the regions of decondensed chromatin within the nuclei were found to be equal. However, in regions of condensed chromatin K+ concentrations were found to be much higher than expected for a Donnan distribution of ions free in solution. Most probably the activity coefficient for K+ is lower in the condensed chromatin than in the decondensed or in the cytoplasm. The same holds true for the A-band as compared to the I-band in heart muscle cells. A sequestration of K+ was measured also in the rough endoplasmic reticulum (RER) of hepatocytes. The Cl? concentration in mitochondria both in heart muscle and liver cells has been measured far in excess of what might be expected from a Nernstian distribution. A coupled inward Cl? transport in mitochondria must, therefore, be assumed.  相似文献   

15.
Cadmium, zinc, selenium, and copper were administered, singly or in combination, orally or subcutaneously. Experiment I included 32 calves of both sexes; six received Cd (two groups), Zn, Cd, and Zn, and Cd and Se (two groups) and one group was a control. In Experiment II (21 bulls), three were given Cd, Cd, and Cu, and Cd and Zn, respectively, and one group was a control. For light microscopy, in Experiment I the highest amounts of silver granules were present in the samples of liver, small intestine, and vesicular gland of all the exposed groups; in Experiment II the most affected organs were liver, kidney, and small intestine. For electron microscopy, in Experiment I, after administration of Cd and Zn, the highest amounts of granules were seen in the cytoplasm of hepatocytes and cells of the proximal and distal renal tubules and the lowest amounts were found in glandular cells of the pancreas. Administration of Cd and Se resulted in the presence of large numbers of granules in the nuclei and nucleoli of spermatogonies. In Experiment II, ingestion of Cd and Zn in feed led to the appearance of highest amounts of granules in the nucleoli, nuclei, and cytoplasm of cells in testes, kidneys, and pancreas. Following Cd intake, the highest accumulation of granules was observed in the nucleoli of hepatocytes and cells of the proximal and distal renal tubules. Combined Cd and Cu produced the highest number of granules in cells of the proximal and distal renal tubules and in the nucleoli and nuclei of germinal epithelium.  相似文献   

16.
Organotypic cultures of the rat hypothalamus are very useful models for the long-term study of parvocellular vasopressin (VP) neurons in the paraventricular (PVN) and suprachiasmatic (SCN) nuclei. However, they do not preserve significant numbers of VP magnocellular neurons (VP-MCNs) in either the PVN or the supraoptic nucleus (SON). Vutskits et al. [(1998) Neuroscience 87:571-582] reported that ciliary neurotrophic factor (CNTF) was a selective survival factor for rat VP-MCNs in organotypic cultures of the rat hypothalamic paraventricular nucleus (PVN). We examined the effects of CNTF on the survival of these neurons in rat and mouse SONs. CNTF (10 ng/ml) in the culture media increased the survival of VP-MCNs by 6-fold and OT-MCNs by 3-fold. In the mouse, both OT- and VP-MCNs survive very well in organotypic cultures under standard culture conditions and the addition of CNTF had no further effect. Consistent with these results, in situ hybridization showed substantially higher levels of VP- and OT-mRNA in rat PVNs and SONs in the presence of CNTF, but produced no changes in these nuclei in the mouse. The optimum period for the survival effect of CNTF on MCNs in the rat hypothalamic cultures was in the first 7-10 days of culture and this effect is maintained for at least 5 additional days if CNTF is then removed from the medium. Therefore, using CNTF in the culture media can provide an opportunity for long-term studies of rat VP- and OT-MCNs in SONs in organotypic cultures.  相似文献   

17.
This study describes the very first assessment of the expression and localization of translationally controlled tumor protein (TCTP) in adult rat urinary organs. TCTP expression levels in kidneys, urinary bladder, and urethra were evaluated by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS–PAGE) and Western blotting, and its cellular localization was examined immunohistochemically in paraffin sections of various urinary organs. TCTP was found in all urinary organs. Its expression was high in the urethra and low in the bladder. TCTP was localized in glomerular podocytes, epithelium of proximal and distal renal tubules, in the loop of Henle, and in the transitional epithelium of the bladder and urethra, mostly in basal cell layers). The subcellular localization of TCTP in these urinary organs was cytoplasmic. These findings suggest that TCTP may be involved in urine formation and excretion. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.  相似文献   

18.
Pituitary adenylate cyclase-activating polypeptide (PACAP), a novel peptide of the secretin/glucagon/vasoactive intestinal polypeptide superfamily, has been initially characterized in mammals in 1989 and, only 2 years later, its counterpart has been isolated in amphibians. A number of studies conducted in the frog Rana ridibunda have demonstrated that PACAP is widely distributed in the central nervous system (particularly in the hypothalamus and the median eminence) and in peripheral organs including the adrenal gland. The cDNAs encoding the PACAP precursor and 3 types of PACAP receptors have been cloned in amphibians and their distribution has been determined by in situ hybridization histochemistry. Ontogenetic studies have revealed that PACAP is expressed early in the brain of tadpoles, soon after hatching. In the frog Rana ridibunda, PACAP exerts a large array of biological effects in the brain, pituitary, adrenal gland, and ovary, suggesting that, in amphibians as in mammals, PACAP may act as neurotrophic factor, a neurotransmitter and a neurohormone.  相似文献   

19.
Role of nerve growth factor in the olfactory system   总被引:1,自引:0,他引:1  
Olfactory neurons are unique in the mammalian nervous system because of their capacity to regenerate in adult animals. It has been shown that olfactory receptor cells located in the olfactory epithelium are replaced on a continuous basis and in response to injury throughout the life span of most species. NGF, which is one of the neurotrophic factors, is present in many areas of the central and peripheral nervous system. It has been shown that NGF in the olfactory bulb plays a role in the survival of cholinergic neurons in the horizontal limb of the diagonal band (HDB). Recent studies of NGF in the olfactory bulb suggest that it is involved in the development, maintenance, and regeneration of olfactory receptor cells. In this study, we review reports examining the relationship between NGF in the olfactory bulb and neuronal regeneration and development in the mammalian olfactory systems. Low- and high-affinity NGF receptor immunoreactivity is markedly expressed during regeneration and at different stages of development in the mouse olfactory system. This level of immunoreactivity is no longer present after completion of regeneration and at maturation. Other findings indicate that NGF injected into the olfactory bulb is transported retrogradely to the olfactory epithelium. It has also been shown that continuous anti-NGF antibody injection into the olfactory bulb causes degeneration and olfactory dysfunction. Administration of NGF directory into nasal cavity results in an increase in the expression of olfactory marker protein within the olfactory epithelium in axotomized rats. These findings suggested that the presence of NGF in the olfactory bulb plays an essential role in regeneration, maintenance, and development in the olfactory system of mammals.  相似文献   

20.
Developmental and seasonal changes in the production of androgens, estrogens, and progestins seem to control sex-specific differentiation and seasonal changes in appetitive and consummatory sexual behaviors of birds. This results in profound sex differences in the quality (sex-specific) or quantity (sex-typical) of behaviors such as courtship, territoriality, or copulation. Steroids affect the brain by binding to intracellularly located receptors. The same brain areas express androgen, estrogen, and progesterone receptors in male and female brains. Sex differences in these genetically determined patterns occur in the size of neuron populations that intrinsically express sex steroid receptors. Further permanent sex differences are subsequent to degenerative fates of receptor expressing neuron populations during ontogeny. Transient sex differences in receptor expression appear to be due to area-specific up- and down-regulation of receptor levels, reflecting transient changes in the level of circulating steroids, changes in environmental conditions, or in the physiological status of the individuals. In particular, intrinsic sex differences in the expression pattern of sex steroid receptors and steroid-independent regulation of the expression level of these receptors in the brain are limiting mechanisms for gonad-dependent sexual development and activities.  相似文献   

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