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101.
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A review of 227 cases of invasive carcinoma of the cervix was undertaken to determine the efficacy of procedures using in the staging of this disease. All patients had a pretreatment chest radiography and intravenous pyelogram. 96.5% had pretreatment cystoscopy, 98.6% had pretreatment proctoscopy, and 92% had a pretreatment barium enema. These patients were retrospectively staged on the findings of physical examination only. Each additional procedure was then evaluated by comparison with the initial staging. Cystoscopy and chest film findings each would have changed the clinical stage in fewer than 1% of cases, barium enema in 1.4%, and proctoscopy in 2.2%. No patient had a positive barium enema without a positive proctoscopy, while two patients had positive proctoscopies with negative barium enemas. The overall yield of positive findings by pretreatment intravenous pyelography was 7.3%. Lymphangiography, although inconsistently done, yielded positive findings in all stages. Chest radiographs, intravenous pyelography, proctoscopy, and lymphangiography are recommended as part of the pretreatment workup of patients with carcinoma of the cervix. Routine barium enema is no longer recommended, and cystoscopy is only recommended in patients with clinical stage IIB disease or greater. 相似文献
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Gallas BD Barrett HH 《Journal of the Optical Society of America. A, Optics, image science, and vision》2003,20(9):1725-1738
Image quality can be objectively defined according to how well an observer can perform a task of practical interest given the image. We review a practical model observer for the signal-detection task. The ideal observer for this task is a function of the image probability distributions, which are multidimensional and complicated. This observer is often too difficult to derive or estimate. An alternative to the ideal observer is the ideal linear observer, which can still be unmanageable. Our alternative is the ideal linear observer constrained to a small set of channels: the channelized-Hotelling observer. 相似文献
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Chris?L.?Barrett Henning?S.?MortveitEmail author Christian?M.?Reidys 《Artificial Life and Robotics》2002,6(4):167-169
We present our work on the special class of dynamical systems referred to as discrete sequential dynamical systems (SDS).
The definition of these systems is motivated by the generic structure of computer simulations. In computer simulations, we
typically find agents or entities with certain properties or states. The entities can retrieve information from other entities,
but usually only from the ones in their own vicinity. Based on these states, they may update their own state. A schedule will
take care of the update order of the entities. One possible interpretation of this is to have each entity as a vertex in a
(dependency) graph where two vertices are connected if the corresponding two entities can communicate. Without loss of generality,
we can associate a binary state to each vertex or entity. Finally, we fix some ordering of the vertices that represents the
update ordering of the entities. The above construction will be put in a strict mathematical context, and leads to the concept
of a sequential dynamical system (SDS).
This work was presented in part at the Sixth International Symposium on Artificial Life and Robotics, Tokyo, January 15–17,
2001 相似文献
108.
Kosslyn Stephen M.; Koenig Olivier; Barrett Anna; Cave Carolyn Backer; Tang Joyce; Gabrieli John D. E. 《Canadian Metallurgical Quarterly》1989,15(4):723
Analyses of human object recognition abilities led to the hypothesis that 2 kinds of spatial relation representations are used in human vision. Evidence for the distinction between abstract categorical spatial relation representations and specific coordinate spatial relation representations was provided in 4 experiments. These results indicate that Ss make categorical judgments—on/off, left/right, and above/below—faster when stimuli are initially presented to the left cerebral hemisphere, whereas they make evaluations of distance—in relation to 2 mm, 3 mm, or 1 in. (2.54 cm)—faster when stimuli are initially presented to the right cerebral hemisphere. In addition, there was evidence that categorical representations developed with practice. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
109.
C Clayton M Adams R Almeida T Baltz M Barrett P Bastien S Belli S Beverley N Biteau J Blackwell C Blaineau M Boshart F Bringaud G Cross A Cruz W Degrave J Donelson N El-Sayed G Fu K Ersfeld W Gibson K Gull A Ivens J Kelly L Vanhamme 《Canadian Metallurgical Quarterly》1998,97(1-2):221-224
We investigated the effect of chronic ethanol administration and its withdrawal on the polypeptide levels of NMDA receptor subunits such as NR1, NR2A, and NR2B in the rat cerebral cortex and hippocampus using Western blot analysis technique. Our results indicate that chronic ethanol treatment upregulates NMDA receptor subunits NR1, NR2A, and NR2B ( approximately 35%). At 48 h of last dose of ethanol administration, the protein content returned to almost control level, thereby demonstrating the reversibility of the changes. 相似文献
110.