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71.
Summary Hydrochlorothiazide, acutely injected in rats, has a weak analgesic activity per se and potentiates and prolongs the antinociceptive effect of morphine.This work was supported in part by grants from Consiglio Nazionale delle Ricerche, and by Ministero della Pubblica Istruzione, Roma.  相似文献   
72.
In October 1924, The Physical Review, a relatively minor journal at the time, published a remarkable two-part paper by John H. Van Vleck, working in virtual isolation at the University of Minnesota. Using Bohr’s correspondence principle and Einstein’s quantum theory of radiation along with advanced techniques from classical mechanics, Van Vleck showed that quantum formulae for emission, absorption, and dispersion of radiation merge with their classical counterparts in the limit of high quantum numbers. For modern readers Van Vleck’s paper is much easier to follow than the famous paper by Kramers and Heisenberg on dispersion theory, which covers similar terrain and is widely credited to have led directly to Heisenberg’s Umdeutung paper. This makes Van Vleck’s paper extremely valuable for the reconstruction of the genesis of matrix mechanics. It also makes it tempting to ask why Van Vleck did not take the next step and develop matrix mechanics himself. This paper was written as part of a joint project in the history of quantum physics of the Max Planck Institut für Wissenschaftsgeschichte and the Fritz-Haber-Institut in Berlin.  相似文献   
73.
74.
Summary Traces of nor-adrenaline restore the vascular action of adrenaline altered in epinephrectomized dogs to the reaction of the normal animal. Therefore it is claimed that the adrenals discharge one or several substances into the blood stream, which are necessary for the usual peripheral vascular action of adrenaline. Further investigations are in progress.  相似文献   
75.
The visual field is topographically mapped onto the primary visual cortex (V1), forming a retinotopic map which is far more detailed for the foveal regions than for the periphery. We found that receptive field (RF) size in monkey V1 increases with eccentricity, and that a 1—2 m2 V1 region contains roughly a complete set of machinery necessary to analyze a visual-field area whose size is about that of the RFs of the cells. This allows V1 to be anatomically uniform, and is in sharp contrast with the retina.  相似文献   
76.
1 Results This paper presents the development of platinum nanocomposites structures based on organically modified c.a.2 nm core platinum nanoparticles.The chemical modification of the 4-mercaptoaniline functionalized particles by various in coming molecules is evidenced and precisely quantified.The particles can be dissolved like molecules in various solvents depending on the features of the new crown and X-rays shows that the interparticle distance is affected by the crown modification.These platinum n...  相似文献   
77.
78.
1 Results The development of the concepts of nanotechnology has given an important impact on the design of new polymer based materials which are in most cases characterized by a multiphase morphology. When at least one phase has nanometric dimension(s) the system can be considered as a nanocomposite where the interface is not only determining for the adhesion but also may play a role in some bulk properties. Indeed in nanostructured multiphase solids the interface is significant as a bulk component. The...  相似文献   
79.
1 Results Pyrimidinones (PMs) are a class of important heterocycles which have been well documented throughout the literature due to their biological importance. They exhibit a wide range of pharmaceutical and therapeutic properties[1].A rapid and efficient one-pot method for the synthesis of 4,6-diarylpyrimidin-2(1H)- ones and related heterocycles is described.The condensation of acetophenone derivatives,aldehydes and urea in the presence of sulfamic acid was employed to synthesize a variety of pyrimid...  相似文献   
80.
Summary The application of diphenylilacetic acid has shown favorable effects on the growth of tobacco plants. Solutions containing 10 p.p.m. and 20 p.p.m. produce, in weight, an almost double growth in treated plants in comparison with the controls. Diphenylilacetic acid can be considered as a growth-promoting substance. The data are not definite.  相似文献   
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