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1.
数列{N(u,v)=2uv+u+v}的若干性质   总被引:5,自引:3,他引:2  
本文得出了数列{N(u,v)=2uv u v}的一些性质,并提出了关于素数的一个猜想。  相似文献   
2.
我国有很多企业实施了ERP项目,但是成功率却很低。从管理和技术两个不同的角度分析了失败的原因,提出了成本一进度管理的观点,并相应地提出了在实施过程中制定工作分解结构、成本进度表和统一软件过程的方案。  相似文献   
3.
Summary A new potent antiauxin, u50768912j24637w/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">-(5,7-dichloroindole-3-)isobutyric acid has been synthesized and shown to inhibit auxin-mediated elongation ofAvena coleoptiles and to stimulate root growth of rice seedlings. Its activity is stronger than u50768912j24637w/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">-(p-chlorophenoxy)isobutyric acid and is comparable to that of 2,3,5-triiodobenzoic acid, which are typical antiauxins.  相似文献   
4.
Summary The profile of action in animals of CQP 201-403, a novel 8u7412w2t30/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">-amino-ergoline, is in most aspects that of a very potent dopaminomimetic, both as a prolactin secretion inhibitor, and at the levels of the CNS and the cardiovascular system. Qualitatively CQP 201-403 differs slightly from bromocriptine and apomorphine in its effects on the CNS (no influence on serotonin metabolism in the rat cortex; induction of masculine mounting behavior in rats) and the cardiovascular system of the dog (reflex tachycardia in response to a blood-pressure fall). In man the new compound proved to be highly active in lowering prolactin serum levels and to be more potent than bromocriptine (Parlodelup>®up>).In memory of Dr Annemarie Closse, who died 14 June 1987.  相似文献   
5.
We demonstrate for the first time a hair cycle-dependent gene and protein expression of proopiomelanocortin in mouse skin in vivo. Northern blot detected POMC mRNA with an apparent size of 0.9 kb in anagen but not telogen skin. Western blot emphasized a specific protein of 30–33 kDa recognized by anti u68m6w833/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-endorphin in late but not early anagen or telogen skin. By immunocytochemistry, u68m6w833/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-endorphin antigen was localized in the sebaceous gland in a hair cycle dependent manner.  相似文献   
6.
In 1986, Brown and Clemmons (Proc. natl Acad. Sci. USA83 (1986) 3321) showed that platelets contain a substance, platelet-derived growth inhibitor (PDGI), that inhibits in vitro endothelial cell replication. Although platelets are rich in transforming grwoth factor u5/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0"> (TGF-u5/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">), PDGI was considered not to be related to TGF-u5/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">, on the basis of its reported properties (extraction from platelets at neutral pH, binding to heparin-Sepharose). However, we purified PDGI to near homogeneity and showed that on the basis of HPLC retention behavior, in vitro growth inhibitory activities with several cell types, receptor binding, and immunoneutralization of growth inhibitory activity with specific anti-TGF-u5/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0"> type 1 antibodies, PDGI is most probably identical with TGF-u5/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0"> type 1.  相似文献   
7.
Adenosine 5u9/xxlarge8242.gif" alt="prime" align="BASELINE" BORDER="0">-triphosphate (ATP) was released into the perfusate of rat isolated mesenteric arterial beds during each of two consecutive increases in flow. There was no significant difference between the amounts of ATP released on each occasion. Substance P was also released into the perfusate by increased flow, although its release was more variable. Removal of the endothelium of the mesenteric vessels with sodium deoxycholate led to a significant reduction (74%) in the amount of ATP released compared with the release before the endothelium had been removed. This suggests that the ATP released into the mesenteric arterial perfusate during increased flow arises from endothelial cells.  相似文献   
8.
总结近两年来有关完全不可约算子更深入的工作。它包括了如下几个方面:(1)完全不可约算子的谱图形和精致的完全不可约算子的存在性;(2)算子的完全不可约分解的唯一性;(3)完全不可约算子的紧扰动和(u+K)轨道。文中列出的一些结果回答了江泽坚、Her-rero有关完全不可约算子的部分猜测和问题。  相似文献   
9.
The isolation of Nu587505226g2h563/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">-quinaldyl-L-arginine·HCl (1) from the CoccinellidaeSubcoccinella-24-punctata is reported. The structure, first established on the basis of the analysis of the spectral properties of1, has been confirmed by synthesis. The alkaloid is of endogenous origin and markedly deterrent to ants.  相似文献   
10.
基于不对称边界的变精度粗糙集的参数选择   总被引:1,自引:0,他引:1  
不对称边界的变精度粗糙集是Pawlak粗糙集、变精度粗糙集的推广,在l和u参数作用下,使粗糙集模型更加一般化,完善了近似空间的概念。基于不对称变精度粗糙集模型研究的基础上,提出了分类质量和依赖度的方法对不精确信息进行度量,对决策表进行约简。在l,u值的选取,提出了单参数控制的方法,通过l,u-质量图分析和计算验证了方法的有效性。  相似文献   
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