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41.
Malcolm W. R. Reed T. Jeffery Wieman Karola W. Doak Catherine G. Pietsch Dale A. Schuschke 《Photochemistry and photobiology》1989,50(3):419-423
Photodynamic therapy (PDT) of malignant tumours may involve the interruption of tumor and peritumor microcirculation. We have studied the effect of light activation of the photosensitizing drug dihematoporphyrin ether (DHE) on rat subcutaneous arterioles and the modulation of these effects by cyclooxygenase inhibitors indomethacin and acetyl salicylic acid (ASA). Animals received DHE 48 h prior to light activation and additionally either indomethacin, ASA or saline 3 h prior to treatment. Light activation (630 nm, 60 J/cm2) resulted in a significant reduction to 62 +/- 2% SEM of initial blood flow. This effect was inhibited by ASA (98 +/- 8% SEM) and indomethacin (87 +/- 8% SEM). Results from the administration of various doses of both compounds indicate that this inhibition is dose related. The data presented here show that PDT causes a significant reduction in blood flow in normal arterioles and that this effect was inhibited by ASA and indomethacin indicating that prostaglandins or thromboxane A2 may play an important role in the microvascular response to PDT. 相似文献
42.
The Cauchy Problem for the equation utt–u+|u|p–1u=0 (x2, t>0, >1) is studied. Smooth Cauchy data is prescribed, and no smallness condition is imposed. For >5, it is shown that the maximum amplitude of such a wave decays at the expected rate t–1/2 as t. For 1+8<5, the maximum amplitude still decays, but at a slower rate. These results are then used to demonstrate the existence of the scattering operator when >o, where o is the root of the cubic equation 3-22-7-8=0; thus o4.15.Alfred P. Sloan Research Fellow 相似文献
43.
44.
Muller A Zhou Y Zhang L Bogge H Schmidtmann M Dressel M Slageren J 《Chemical communications (Cambridge, England)》2004,(18):2038-2039
The highly charged nanocontainer capsule of the type [pentagon]12[linker]30 identical with [(Mo)Mo5O21(H2O)6]12[Mo2O4(SO4)]30 with 20 nanosized pores and channels allows the entrance of cations like Pr3+: the latter are positioned at two different sites and have two different coordination shells, corresponding to a coordination chemistry under confined conditions; a fascinating aspect is that capsule encapsulated water shells fixed by hydrogen bonds act formally as polydentate ligands. 相似文献
45.
46.
Tsirelson Vladimir Abramov Yury Zavodnik Valery Stash Adam Belokoneva Elena Stahn Jochen Pietsch Ullrich Feil Dirk 《Structural chemistry》1998,9(4):249-254
The critical points in the model electron density distributions of LiF, NaF, NaCl, and MgO crystals, constructed from accurate X-ray diffraction data, are determined. For LiF and MgO they are compared with those obtained from a Hartree–Fock electron density calculation. Both experiment and theory show the same type of critical points on the bond lines. The topological features in areas between structural units, where the electron density is low and near-uniform, turn out to be model dependent and cannot be established well with the data available. Topological analysis of procrystals (hypothetical systems consisting of spherical atoms or ions placed on the same sites as atoms in real crystal) show that (3, –1) critical points, usually connected with bonding interaction, are observed on interatomic lines in these nonbonded systems as well. 相似文献
47.
Markus Pietsch Martin Nieger Michael Gütschow 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(3):o147-o151
The title compounds, tert‐butyl 6‐benzyl‐2‐(3,3‐diethylureido)‐4,5,6,7‐tetrahydrothieno[2,3‐c]pyridine‐3‐carboxylate, C24H33N3O3S, (I), 7‐benzyl‐2‐diethylamino‐5,6,7,8‐tetrahydro‐3‐oxa‐9‐thia‐1,7‐diazafluoren‐4‐one, C20H23N3O2S, (II), and N‐(7‐benzyl‐4‐oxo‐5,6,7,8‐tetrahydro‐4H‐3,9‐dithia‐1,7‐diazafluoren‐2‐yl)benzamide, C23H19N3O2S2, (III), form monoclinic crystal systems. In (I) and (II), the molecules are linked into a three‐dimensional framework by weak intermolecular C—H⋯O=C hydrogen bonds, whereas in (III) stronger intermolecular N—H⋯O=C interactions are observed. The conformation of (I) is further stabilized by an intramolecular N—H⋯O=C hydrogen bond, which effects the planarity of the ureidothiophenecarboxylate moiety. 相似文献
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49.
Markus Follmann Nils Griebenow Michael G. Hahn Ingo Hartung Franz‐Josef Mais Joachim Mittendorf Martina Schfer Hartmut Schirok Johannes‐Peter Stasch Friederike Stoll Alexander Straub Peter Jeschke Ralf Nauen Michael Edmund Beck Hans‐Wilhelm Engels Hans‐Georg Pirkl Reinhard Albers Rolf W. Albach Jens Krause Andreas Hoffmann Holger Casselmann Jeff Dormish 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2013,125(36):9503-9503
50.
The landscape of synchrotron radiation facilities in Europe is diverse. In addition to the flagship ESRF, several national facilities exist or came into operation recently. In contrast to ESRF, which is financed for use by member countries, access of foreign users to national facilities is not easy. Even if their proposals pass the review process, they can only perform the experiments if funding is allocated to cover not only travel expenses, board and lodging of the experimenters, but also some compensation for the facility's operational costs; this is because national facilities are primarily funded for the home-country's users at that nation's costs. 相似文献