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951.
952.
基于MFC的Windows下多进程消息通信技术及应用   总被引:1,自引:0,他引:1  
介绍了一种基于MFC的Windows下多进程通信方法和技术——消息通信,简介了MFC下的消息通信机制,并采用了“钩子”机制和转发机制实现了在任意类下的消息通信。同时根据实际的开发经验,举出了一个使用MFC开发的详细实例。  相似文献   
953.
阐述了采用Netfilter/iptables技术来实现NAT的缘由 ,并分析了此项技术在Linux内核 2 .4中的一个重要新特性 ,即“连接跟踪” ;着重讨论了提高基于配有Linux操作系统的普通PC机上的NAT性能的方法 ,包括重编内核 ,防止空对话及修改tcp连接超时设定 ;通过一组系统状态监测曲线图证明这样一个廉价系统作为一些昂贵的路由设备的替代是稳定可靠的  相似文献   
954.
Hydrogen storage of aligned multi-walled carbon nanotubes (a-MWNTs),non-aligned MWNTs(n-MWNTs) and graphite electrodes are studied by the electro-chemical measurements .The electrodes are prepared by mixing carbon nanotubes (CNTs) copper powder and ptfe binder in a weight ratio of 1:5:3 and compressing the mixture into porous nickel collector,The results show that the electrochemical hydrogen storage capacity of the a-MWNT electrode is up to 1625 mAh/g corresponding to a high hydrogen storage of 5.7 wt% ,which is 10 times that of graphite electrode and is 13 times that of n-MWNT electrode, suggesting that a-MWNTs are promising materials for electrochemical hydrogen storage.  相似文献   
955.
Self-assembled complexes between cage com-pounds cucurbit[n = 5—8]urils and hexamethylenetetramine were studied by using NMR techniques. Experimental results reveal that hexamethylenetetramine can lid cucurbit[5]uril to forming self-assembled capsules in which nothing is encap-sulated yet; the cavity of the cucurbit[7]uril can accommo-date a hexamethylenetetramine molecule to form a self- assembled host-guest inclusion. Moreover, both the cavity interaction of the cucurbit[7]uril with hexamethylenetetra-mine稨Cl and the portal interaction of the dipole carbonyl of the cucurbit[7]uril with hexamethylenetetramine稨Cl lead to form self-assembled capsules in which the hexamethylene-tetramine稨Cl are encapsulated in the hexamethylenetetra-mine稨Cl lidded cucurbit[7]uril. Although the structures of the portal and cavity to cucurbit[5]uril are similar, there is no obvious interaction between decamethylcucurbit[5]uril and hexamethylenetetramine, and also between cucurbit [6]uril or cucurbit[8]uril and hexamethylenetetramine.  相似文献   
956.
Dealing with a Differentiated Whole: The Philosophy of the WSR Approach   总被引:1,自引:0,他引:1  
This paper seeks to explore a philosophical ground for the formulation and practice of an Oriental systems methodology, the wuli–shili–renli approach (WSR). Drawing insights from ancient Chinese thought, WSR contends that, in sociotechnical systems design/management, we should investigate and follow wuli, shili, and renli, which constitute a differentiable, dynamic whole. Wuli, shili, and renli condition and determine the fate of our projects, meaning different methods are needed to deal with each differentiable aspect. It also points out that, to deal with wuli, shili, and renli properly, we need to engage in encounters with the "dark side" of Confucianism and with the contemporary tendency of scientism.  相似文献   
957.
958.
Two yeast forkhead genes regulate the cell cycle and pseudohyphal growth   总被引:36,自引:0,他引:36  
Zhu G  Spellman PT  Volpe T  Brown PO  Botstein D  Davis TN  Futcher B 《Nature》2000,406(6791):90-94
  相似文献   
959.
Extracellular ATP is implicated in numerous sensory processes ranging from the response to pain to the regulation of motility in visceral organs. The ATP receptor P2X3 is selectively expressed on small diameter sensory neurons, supporting this hypothesis. Here we show that mice deficient in P2X3 lose the rapidly desensitizing ATP-induced currents in dorsal root ganglion neurons. P2X3 deficiency also causes a reduction in the sustained ATP-induced currents in nodose ganglion neurons. P2X3-null mice have reduced pain-related behaviour in response to injection of ATP and formalin. Significantly, P2X3-null mice exhibit a marked urinary bladder hyporeflexia, characterized by decreased voiding frequency and increased bladder capacity, but normal bladder pressures. Immunohistochemical studies localize P2X3 to nerve fibres innervating the urinary bladder of wild-type mice, and show that loss of P2X3 does not alter sensory neuron innervation density. Thus, P2X3 is critical for peripheral pain responses and afferent pathways controlling urinary bladder volume reflexes. Antagonists to P2X3 may therefore have therapeutic potential in the treatment of disorders of urine storage and voiding such as overactive bladder.  相似文献   
960.
采用气相色谱-质谱联用技术,首次对木果楝叶子和果实挥发油进行了成分分析,从木果楝叶子和果实分别鉴定出了33和36种化合物,分别占挥发油的99.11%和97.63%.两个部位中挥发油化学组成各有异同,但其主要成分均是倍半萜类化合物b-桉叶烯和γ-桉叶烯.本研究结果可为木果楝的综合开发利用提供理论依据.  相似文献   
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