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排序方式: 共有893条查询结果,搜索用时 15 毫秒
111.
112.
In immunocytes from the mollusc Mytilus galloprovincialis, the major pathway followed by platelet-derived growth factor (PDGF)-AB and transforming growth factor (TGF)-beta1 in provoking the release of norepinephrine, epinephrine and dopamine into cell-free hemolymph (serum) is mediated by a corticotropin-releasing hormone-adrenocorticotropin hormone (CRH-ACTH) biogenic amine axis. This axis not only annulled the inhibiting properties of PDGF-AB, it even reversed the latter's effect, while the inducing effect of TGF-beta1 was amplified. These findings show that non-classical immune-neuroendocrine molecules, such as PDGF-AB and TGF-beta1, are involved in building stress response, using the same conserved mechanisms present from invertebrates to vertebrates. 相似文献
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Jean-Marc David Jean-Paul Krivine Jean-Pierre Tiarri Benoit Ricard 《Journal of Intelligent and Robotic Systems》1988,1(3):287-298
DIVA is an expert system for turbine generator diagnosis. Its aim is to help a plant operator interpret vibration evolution to diagnose developing faults. Interpretation of vibration evolution is primarily a recognition process which is achieved by a particular model of heuristic classification. DIVA tries to recognize the observed situation among a hierarchy of typical situations.The purpose of this paper is to present the model we used for heuristic classification, based on prototypes. Prototypes represent typical problem situations and may also be seen as experts with special knowledge of what to do in such situations. We argue that this model presents significant advantages to deal with complex problems such as vibration surveillance. 相似文献
116.
T Essam E Tamer M A Amin O El Tayeb B Mattiasson B Guieysse E T Ossama M Bo G Benoit 《Water science and technology》2006,53(11):117-125
An algal-bacterial consortium was tested for the treatment from a coke factory. A Chlorella vulgaris strain and a phenol-degrading Alcaligenes sp. were first isolated from the wastewater treatment plant to serve as inocula in the subsequent biodegradation tests. Batch tests were then conducted with samples from the real wastewater or using a synthetic wastewater containing 325 mg phenol/l and 500 mg NH4+/l as target pollutants. Direct biological treatment of the real wastewater was not possible due to the toxicity of organic compounds. Activated carbon adsorption and UV(A-B)-irradiation were efficient in detoxifying the effluent for subsequent biological treatment as inoculation of pretreated samples with the algal-bacterial consortium was followed by complete phenol removal and NH4+ removal of 45%. Complete phenol removal and 33% NH4+ removal were achieved during the fed-batch treatment of artificial wastewater at 6 d hydraulic retention time (HRT). Under continuous feeding at 3.6 d HRT, phenol and NH4+ removal dropped to 58 and 18%, respectively. However, complete phenol removal and 29% NH4+ removal were achieved when 8 g NaHCO3/l was added to the artificial wastewater to enhance algal growth. This study confirms the potential of solar-based industrial wastewater treatment based on solar-based UV pretreatment followed by algal-bacterial biodegradation. 相似文献
117.
Emo Welzl 《Information Processing Letters》1985,20(4):167-171
Given a set S of line segments in the plane, its visibility graph GS is the undirected graph which has the endpoints of the line segments in S as nodes and in which two nodes (points) are adjacent whenever they ‘see’ each other (the line segments in S are regarded as nontransparent obstacles). It is shown that GS can be constructed in O(n2) time and space for a set S of n nonintersecting line segments. As an immediate implication, the shortest path between two points in the plane avoiding a set of n nonintersecting line segments can be computed in O(n2) time and space 相似文献
118.
C?té Guylaine; Gauthier Janel G.; Laberge Benoit; Cormier Hugues J.; Plamondon Jacques 《Canadian Metallurgical Quarterly》1993,25(1):45
Reviews the mainly English-language clinical research and some studies by the present authors on the use of cognitive and behavioral procedures to treat panic disorder. Controlled studies and noncontrolled studies are considered. Use of relaxation, respiratory control, and exposure is discussed. (English abstract) (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
119.
Optically active (?)menthylethylfumarate (2) and (?)dimenthylfumarate (3) have been synthesised and free radically copolymerized with N-vinylcarbazole (1). Copolymers of (1) and (2) exhibit a strong tendency to alternation in agreement with earlier conclusions from studies of copolymerization of (1) with diethylfumarate. Surprisingly the much more hindered, but symmetrical fumarate, (3) yields copolymers which always have carbazole monomer contents in excess of the 1:1 alternating ratio. Chiroptical measurements indicate significant induced optical activity in the carbazole chromophores of all the copolymers obtained but, in accord with the predominance of alternating structures, there is no real evidence for any sequence-determined maximum in induced circular dichroism. Fluorescence emission spectra of all copolymer samples exhibit significant asymmetric broadening on the long wavelength (low energy) side of the normal carbazole monomeric emission. This broadening is exhibited even by poly (1-co-2) samples for which the monomer compositions strongly indicate alternating sequences and must, therefore, represent interaction between carbazole segments. Accordingly, and in contrast to widely held assumptions, it is concluded that excimer-like emission may be exhibited by alternating copolymers of N-vinylcarbazole. Further evidence for electronic interactions between non-nearest neighbour carbazole units is provided by u.v. absorption and 1H-n.m.r. spectra of appropriate copolymers. 相似文献
120.
A new preparative liquid-phase chromatograph, operating at a high temperature (160°C), allowed us to fractionate a linear polyethylene sample in narrow fractions (polydispersity about 1.1). These fractions, characterized by viscosity, light scattering, osmometry, and GPC measurements, can be used to calibrate any analytical GPC, i.e., to determine the variation of molecular weight and axial dispersion versus the elution volume. 相似文献