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401.
IntroductionStormwater management(SWM) in Hong Kong isthe responsibility of the drainage servicesdepartment (DSD) of the Governmentof the HongKong Special Administrative Region.Thedepartment is charged with the formulation ofpolicy and the design,construction,operation andmaintenance of all public stormwater drainagesystems,as well as approving private drainsthrough an administrative framework. The principal concern of SWM is the reductionof the risk and extent of flooding.Thus,thesuc… 相似文献
402.
添加剂对AN多变晶型影响研究 总被引:1,自引:0,他引:1
本文运用热分析的方法对四十余种无机、有机添加剂和几种表面活性剂及水分对硝酸铵(AN)晶型转变的影响进行了研究。结果表明这些添加剂对AN的影响应为多种因素的综合结果。 相似文献
403.
本文论述闭式双动机械压力机外滑块八连杆机构优化设计时数学模型如何建立、优化方法怎样选择等问题。通过计算实例可以看出优化结果与维尔森公司计算结果的比较。 相似文献
404.
N de Wind M Dekker N Claij L Jansen Y van Klink M Radman G Riggins M van der Valk K van't Wout H te Riele 《Nature genetics》1999,23(3):359-362
Cancer predisposition in hereditary non-polyposis colon cancer (HNPCC) is caused by defects in DNA mismatch repair (MMR). Mismatch recognition is attributed to two heterodimeric protein complexes: MutSalpha (refs 2, 3, 4, 5), a dimer of MutS homologues MSH2 and MSH6; and MutSbeta (refs 2,7), a dimer of MSH2 and MSH3. These complexes have specific and redundant mismatch recognition capacity. Whereas MSH2 deficiency ablates the activity of both dimers, causing strong cancer predisposition in mice and men, loss of MSH3 or MSH6 (also known as GTBP) function causes a partial MMR defect. This may explain the rarity of MSH6 and absence of MSH3 germline mutations in HNPCC families. To test this, we have inactivated the mouse genes Msh3 (formerly Rep3 ) and Msh6 (formerly Gtmbp). Msh6-deficient mice were prone to cancer; most animals developed lymphomas or epithelial tumours originating from the skin and uterus but only rarely from the intestine. Msh3 deficiency did not cause cancer predisposition, but in an Msh6 -deficient background, loss of Msh3 accelerated intestinal tumorigenesis. Lymphomagenesis was not affected. Furthermore, mismatch-directed anti-recombination and sensitivity to methylating agents required Msh2 and Msh6, but not Msh3. Thus, loss of MMR functions specific to Msh2/Msh6 is sufficient for lymphoma development in mice, whereas predisposition to intestinal cancer requires loss of function of both Msh2/Msh6 and Msh2/Msh3. 相似文献
405.
Countercurrent chromatography meets MS 总被引:1,自引:0,他引:1
Interfacing countercurrent chromatography with thermospray mass spectrometry provides a new analytical tool for detecting nonvolatile, hydrophilic or thermally unstable bioactive natural products. 相似文献
406.
A superantigen encoded in the open reading frame of the 3' long terminal repeat of mouse mammary tumour virus. 总被引:36,自引:0,他引:36
Mice express a collection of superantigens, which bind to class II major histocompatibility proteins and interact with T cells bearing particular V beta chains as part of their alpha beta receptors. These superantigens have been suggested to be encoded by exogenous or endogenous mouse mammary tumour viruses. One such superantigen is now shown to be encoded in the open reading frame of the long terminal repeat of a mammary tumour virus, a gene of previously unknown function. 相似文献
407.
Scavenger receptor family proteins: roles for atherosclerosis, host defence and disorders of the central nervous system 总被引:11,自引:1,他引:10
Y. Yamada T. Doi T. Hamakubo T. Kodama 《Cellular and molecular life sciences : CMLS》1998,54(7):628-640
In this review, we summarize the structure and function of the scavenger receptor family of proteins including class A (type
I and II macrophage scavenger receptors, MARCO), class B (CD36, scavenger receptor class BI), mucinlike (CD68/macrosialin,
dSR-CI) and endothelial (LOX-1) receptors. Two motifs have been identified as ligand-binding domains a charged collagen structure
of type I and II receptors, and an immunodominant domain of CD36. These structures can recognize a wide range of negatively
charged macromolecules, including oxidized low-density lipoproteins, damaged or apoptotic cells, and pathogenic microorganisms.
After binding, these ligands can be either internalized by endocytosis or phagocytosis, or remain at the cell surface and
mediate adhesion or lipid transfer through caveolae. Under physiological conditions, scavenger receptors serve to scavenge
or clean up cellular debris and other related materials, and they play a role in host defence. In pathological states, they
mediate the recruitment, activation and transformation of macrophages and other cells which may be related to the development
of atherosclerosis and to disorders caused by the accumulation of denatured materials, such as Alzheimer's disease.
Received 17 September 1997; received after revision 16 March 1998; accepted 17 March 1998 相似文献
408.
人口老龄化已经成为世界各国、各地区社会经济发展面临的重要问题。中国从2001年步入老龄化社会,提升老龄群体生活质量对于全面实现小康社会意义重大,也是促进中国城镇化健康发展的需要。梳理了中国20世纪80年代以来养老政策和实践的演进路径,强调了居家养老既要符合中国社会经济发展的特征,也要满足老龄群体的生活需求;鉴于中国社区的养老服务设施供给仍然滞后于老龄化发展的现状,探讨了在智慧社会下,通过信息化策略(虚拟空间)与可步行邻里环境(实体空间),提升已有养老服务设施的服务覆盖面和质量、构建老龄群体的智慧社区生活模式、促进居家养老服务的时空匹配、提升居家养老服务的质量水平等策略。 相似文献
409.
To test the effect of L-carnitine on glycogen sparing when fat oxidation is increased, 100 mg/kg/d were given to rats orally for 3 days, resulting in 1.8-fold higher muscle carnitine levels. Even when FFA were raised by heparin-stimulated lipolysis, the rate of glycogen degradation was not reduced during exercise. 相似文献
410.
王引田 《科技情报开发与经济》2004,14(6):170-171
基于引黄连接段河口至扫石公路的控制性工程——2#隧道破碎段的工程概况与工程地质条件,着重介绍了其支护方案的比选。 相似文献