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121.
Dose relationships of morning bright white light in seasonal affective disorders (SAD) 总被引:1,自引:0,他引:1
A Wirz-Justice A C Schmid P Graw K Kr?uchi P Kielholz W P?ldinger H U Fisch C Buddeberg 《Experientia》1987,43(5):574-576
Bright white full spectrum light (greater than 2500 lux) can improve depressive symptomatology in a selected group of patients with recurrent autumn and winter depression. This crossover study demonstrates that 0.5-h morning white light is not an effective treatment, whereas 2-h is. 相似文献
122.
A. Wirz-Justice A. C. Schmid P. Graw K. Kräuchi P. Kielholz W. Pöldinger H. -U. Fisch C. Buddeberg 《Cellular and molecular life sciences : CMLS》1987,43(5):574-576
Summary Bright white full spectrum light (>2500 lux) can improve depressive symptomatology in a selected group of patients with recurrent autumn and winter depression. This crossover study demonstrates that 0.5-h morning white light is not an effective treatment, whereas 2-h is. 相似文献
123.
In the unactivated Limulus sperm, a 60- micro m-long bundle of actin filaments crosslinked by the protein scruin is bent and twisted into a coil around the base of the nucleus. At fertilization, the bundle uncoils and fully extends in five seconds to support a finger of membrane known as the acrosomal process. This biological spring is powered by stored elastic energy and does not require the action of motor proteins or actin polymerization. In a 9.5-A electron cryomicroscopic structure of the extended bundle, we show that twist, tilt and rotation of actin-scruin subunits deviate widely from a 'standard' F-actin filament. This variability in structural organization allows filaments to pack into a highly ordered and rigid bundle in the extended state and suggests a mechanism for storing and releasing energy between coiled and extended states without disassembly. 相似文献
124.
Greiner J Klose S Reinsch K Schmid HM Sari R Hartmann DH Kouveliotou C Rau A Palazzi E Straubmeier C Stecklum B Zharikov S Tovmassian G Bärnbantner O Ries C Jehin E Henden A Kaas AA Grav T Hjorth J Pedersen H Wijers RA Kaufer A Park HS Williams G Reimer O 《Nature》2003,426(6963):157-159
The association of a supernova with GRB030329 strongly supports the 'collapsar' model of gamma-ray bursts, where a relativistic jet forms after the progenitor star collapses. Such jets cannot be spatially resolved because gamma-ray bursts lie at cosmological distances; their existence is instead inferred from 'breaks' in the light curves of the afterglows, and from the theoretical desire to reduce the estimated total energy of the burst by proposing that most of it comes out in narrow beams. Temporal evolution of the polarization of the afterglows may provide independent evidence for the jet structure of the relativistic outflow. Small-level polarization ( approximately 1-3 per cent) has been reported for a few bursts, but its temporal evolution has yet to be established. Here we report polarimetric observations of the afterglow of GRB030329. We establish the polarization light curve, detect sustained polarization at the per cent level, and find significant variability. The data imply that the afterglow magnetic field has a small coherence length and is mostly random, probably generated by turbulence, in contrast with the picture arising from the high polarization detected in the prompt gamma-rays from GRB021206 (ref. 18). 相似文献
125.
Summary The structure of Visamminol (I), a compound isolated fromAmmi visnaga bySmith, Pucci, andBywater, has been elucidated by degradation and by a comparison of the UV.-spectra of I and its derivatives with those of other chromones. 相似文献
126.
Thalidomide in rabbit semen 总被引:4,自引:0,他引:4
127.
Glutamine synthetase (GS) of human liver was recognized with a polyclonal antibody to pig brain GS, but failed to stain with an antibody against rat liver GS. Using the latter antibody GS of human liver was shown to be localized within small rings of 1 to 3 hepatocytes surrounding the terminal hepatic venules. This pattern was analogous to that seen in rat and mouse liver. 相似文献