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941.
Background
Statistics is relevant to students and practitioners in medicine and health sciences and is increasingly taught as part of the medical curriculum. However, it is common for students to dislike and under-perform in statistics. We sought to address these issues by redesigning the way that statistics is taught. 相似文献942.
Philippe A. Puech Loïc Boussel Samir Belfkih Laurent Lemaitre Philippe Douek Régis Beuscart 《Journal of digital imaging》2007,20(2):122-130
DicomWorks is freeware software for reading and working on medical images [digital imaging and communication in medicine (DICOM)].
It was jointly developed by two research laboratories, with the feedback of more than 35,000 registered users throughout the
world who provided information to guide its development. We detail their occupations (50% radiologists, 20% engineers, 9%
medical physicists, 7% cardiologists, 6% neurologists, and 8% others), geographic origins, and main interests in the software.
The viewer’s interface is similar to that of a picture archiving and communication system viewing station. It provides basic
but efficient tools for opening DICOM images and reviewing and exporting them to teaching files or digital presentations.
E-mail, FTP, or DICOM protocols are supported for transmitting images through a local network or the Internet. Thanks to its
wide compatibility, a localized (15 languages) and user-friendly interface, and its opened architecture, DicomWorks helps
quick development of non proprietary, low-cost image review or teleradiology solutions in developed and emerging countries. 相似文献
943.
Bettina H Clausen Kate L Lambertsen Alicia A Babcock Thomas H Holm Frederik Dagnaes-Hansen Bente Finsen 《Journal of neuroinflammation》2008,5(1):46
Background
Interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) are expressed by microglia and infiltrating macrophages following ischemic stroke. Whereas IL-1β is primarily neurotoxic in ischemic stroke, TNF-α may have neurotoxic and/or neuroprotective effects. We investigated whether IL-1β and TNF-α are synthesized by overlapping or segregated populations of cells after ischemic stroke in mice. 相似文献944.
Chong-Su Cho Tadashi K
moto Akira Nakagami Tohru Kawai 《Macromolecular chemistry and physics.》1979,180(8):1951-1959
Ionic polymer-polymer interaction was studied in aqueous solution for poly(L -lysine) (PLL) and sulfated poly(vinyl alcohol) (PVS) as functions of pH, the degree of sulfation, the functional unit mole ratio of the two polymers and temperature by means of circular dichroism and viscosity measurements. In all the cases studied, strong inter-polymer complexes were formed at the functional unit mole ratio (VS)/(LL) higher than 1. Although PLL itself is well known to take the α-helical conformation at such a high pH as 11, the PLL conformation in the PLL/PVS complexes did not depend on pH but on the degree of sulfation: at room temperature, PLL took random coil conformation in PLL/PVS-25 (25: degree of sulfation in mole-%) and PLL/PVS-30, and the α-helical conformation (helicity of 70%) in PLL/PVS-46 and PLL/PVS-95. Models for the complex structures are postulated. Methanesulfonic acid did not influence the conformational transition of PLL, supporting that a polymer effect took place in the complex formation between PLL and PVS. Thermal effect on the PLL conformation in the complex is also discussed. 相似文献
945.
Plasmids containing the inosine monophosphate dehydrogenase gene CaIMH3 from Candida albicans strain ATCC 32354 transform their host to resistance against mycophenolic acid (MPA). The transformants maintain the plasmids at a high copy number (20–40 per cell) and express the CaIMH3 gene at very high levels relative to untransformed controls. The plasmid copy number can be controlled by the concentration of MPA in the media. The transformation procedure is reproducible and the efficiency of transformation is high, up to 15,000 per microgram. Unrearranged plasmids are readily recovered by transforming total DNA from transformants back into Escherichia coli. C. albicans genes cloned into the plasmid are expressed at elevated levels relative to untransformed controls. A derivative vector containing the CaMAL2 promoter and termination sequences expresses the CaERG11 ORF at high levels and confers moderate resistance to fluconazole. These shuttle vectors should facilitate global genomics approaches in C. albicans that have been hampered by its diploid genome. 相似文献
946.
Morishima Y Ishii Y Kimura T Shibuya A Shibuya K Hegab AE Iizuka T Kiwamoto T Matsuno Y Sakamoto T Nomura A Taniguchi M Sekizawa K 《European journal of immunology》2005,35(10):2803-2814
To clarify the essential role of NKT cells in allergy, we investigated the contribution of NKT cells to the pathogenesis of eosinophilic airway inflammation using alpha-galactosylceramide (alpha-GalCer), a selective ligand for NKT cells. Although continuous administration of alpha-GalCer during ovalbumin (OVA) sensitization increased OVA-specific IgE levels and worsened eosinophil inflammation, a single administration of alpha-GalCer at the time of OVA challenge completely prevented eosinophilic infiltration in wild-type mice. This inhibitory effect of alpha-GalCer was associated with a decrease in airway hyperresponsiveness, an increase in IFN-gamma, and decreases in IL-4, IL-5 and IL-13 levels in the bronchoalveolar lavage fluids. Analysis of lung lymphocytes revealed that production of IFN-gamma increased in NK cells, but not in T or NKT cells, following alpha-GalCer administration. Induction of vascular cell adhesion molecule-1 in the lungs of wild-type mice was also significantly attenuated by treatment with alpha-GalCer. These effects of alpha-GalCer were abrogated in J alpha281-/- mice, which lack NKT cells, and in wild-type mice treated with anti-IFN-gamma Ab. Hence, our data indicate that alpha-GalCer suppresses allergen-induced eosinophilic airway inflammation, possibly by inducing a Th1 bias that results in inhibition of eosinophil adhesion to the lung vessels. 相似文献
947.
948.
Millar M 《Journal of behavioral medicine》2005,28(5):425-432
This study examined the impact of perceived stress on responses to messages that encouraged the performance of health promotion
and disease detection behaviors. It was hypothesized that increases in perceived stress would be associated with decreased
processing of messages encouraging disease detection behaviors, and that increases in perceived stress would not effect the
processing of messages encouraging health promotion behaviors. To test these hypotheses participants completed a perceived
stress measure and then read a message that encouraged the performance of either a health promotion or a disease detection
behavior. Then the participants were asked to indicate their agreement with the message and to attempt to recall the message.
The results indicated that participants experiencing higher levels of perceived stress spent less time reading and recalled
less of the messages about detection behaviors than of the messages about promotion behaviors. When participants were experiencing
lower levels of perceived stress these differences disappeared.
相似文献
相似文献
949.
950.
Hiroyuki Nakamura Takashi Moroji Hirofumi Nagase Takao Okazawa Akira Okada 《European journal of applied physiology》1994,68(1):62-67
To clarify the role of vasoactive intestinal polypeptide (VIP) and somatostatin, somatropin-release inhibiting factor, (SRIF) neurons in the response to organisms to noise or whole-body vibration stress, VIP and SRIF-like immunoreactivity were determined in various regions of the rat brain following exposure for 90 min to noise (broad band, 102 dB) or whole-body vibration (20 Hz, 4.0 g). Both noise and whole-body vibration significantly increased VIP-like immunoreactivity in the amygdala. A significant reduction of VIP like immunoreactivity in the hippocampus was induced only by whole-body vibration. On the other hand SRIF-like immunoreactivity was decreased significantly in the hypothalamus and increased significantly in the amygdala by noise and whole-body vibration, respectively. The present findings would seem to indicate that the amygdalofugal VIP neural system is involved in regulating hypothalamic and pituitary hormone secretions in non-specific reactions to stress. Responses of hippocampal VIP and the amygdalofugal SRIF to whole-body vibration stress are assumed to be activated as specific reactions to the stress. 相似文献