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J Voges  V Sturm  R Lehrke  H Treuer  C Gauss  F Berthold 《Canadian Metallurgical Quarterly》1997,40(2):263-9; discussion 269-70
OBJECTIVE: Long-term follow-up data were analyzed to assess the value of intracavitary irradiation with stereotactically applied beta-emitting radioisotopes for the treatment of craniopharyngioma cysts. METHODS: Sixty-two of 70 consecutive patients with predominantly cystic craniopharyngiomas were selected for retrospective analysis. Beta-Emitting isotopes were injected intracystically using a computed tomography-guided and computer-assisted three-dimensional stereotactic treatment planning and application system (cumulative dose to the inner surface of the cyst wall, 200 Gy). RESULTS: The tumor response rate gained with yttrium-90-labeled silicate (66 of 78 cysts) or phosphorous-32-labeled chromic phosphate (8 of 78 cysts) was 79.5%. Four cysts treated with rhenium-186-labeled sulfate did not respond. Mean survival after intracavitary irradiation was 9.0 +/- 0.9 years (median follow-up, 11.9 yr). In patients with solitary cysts, the mean survival was 12.5 +/- 1.4 years (actuarial 5- and 10-yr survival rates, 80 and 64%, respectively). Six months postoperatively, visual deficits (38 of 62 patients) had improved in 23 patients and were stable in 15 patients. The side effects that occurred 6 to 12 months after treatment with yttrium-90 were complete blindness (three patients), worsening of visual field cuts (one patient), third nerve palsy (one patient), and diabetes insipidus and/or panhypopituitarism (three patients). CONCLUSIONS: Intracavitary irradiation using yttrium-90 or phosphorous-32 is highly effective in the treatment of cystic craniopharyngiomas. If applied as initial treatment in patients with solitary cysts, it is the only required therapy over a long period.  相似文献   
33.
In this paper an empirical Bayes model is developed to monitor and analyse discrete data generated in a manufacturing process for printed circuit boards. A key feature of this analysis is the use of the current observation at time t and the posterior estimates of the distribution of the proportion nonconforming at time t – 1 to obtain a new, updated estimate of the posterior distribution at time t. The derived approach is widely applicable to statistical process control and provides a simple and fast algorithm for updating.  相似文献   
34.
Einfluß von Wärmedehnungen auf das Spannungs- und Dehnungsverhalten fester Körper und Formulierung der Spannungs- und Dehnungsbeziehungen in Matrizenform für ebene und axialsymmetrische Probleme. Überprüfung der Aussagemöglichkeiten des Verfahrens anhand von Anwendungsbeispielen.  相似文献   
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The burst behaviour of fourteen vessels containing longitudinal flaws was investigated. The vessels were made of the two steels: 20 MnMoNi 5 5 with a high upper shelf impact toughness and a special melt of 22 NiMoCr 3 7 with a low upper-shelf impact toughness. The dimensions of the vessels were the same as of the pipes of the primary coolant system (798 O.D. × 47.5 mm wall thickness) of a pressurized water reactor. The test pressure and temperature correspond with the real service conditions of a PWR.Using a highly sophisticated measuring equipment, the time-history of pressure, crack opening and crack-opening area were determined experimentally.  相似文献   
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The objectives of this study were (1) to develop an algorithm for the acceleration sensor of the Smartbow Eartag (Smartbow GmbH, Weibern, Austria) to distinguish between postures (lying and standing or locomotion) and to detect 6 kinds of activities (milk intake, water intake, solid feed intake, ruminating, licking or sucking without milk intake, and other activities) in dairy calves and (2) to evaluate this sensor for identifying these behaviors in dairy calves compared with observations from video. Accelerometers were applied to the left ears of 15 preweaned Holstein dairy calves. Calves were kept in a group pen and received milk replacer from an automatic calf feeder. Based on 38 h of acceleration data and video observation, an algorithm was established to detect the predefined behaviors. Using cross-validation, video recordings were used to analyze whether a behavior was detected correctly by the developed algorithm. For posture, sensitivity (94.4%), specificity (94.3%), precision (95.8%), and accuracy (94.3%) were high. Cohen's kappa was calculated as 0.88. For the 6 defined activities, overall (i.e., aggregated for all activities) accuracy was 70.8% and kappa was calculated as 0.58. Some activities (e.g., ruminating, feed intake, other activities) were identified better than others. In conclusion, the developed algorithm based on the acceleration data of the Smartbow Eartag was successful in detecting lying behavior, rumination, feed intake, and other activities in calves, but further development of the underlying algorithm will be necessary to produce reliable results for milk and water intake.  相似文献   
39.
The ability of the "conceptual-area" scoring system to differentiate between tuberculous, process schizophrenic, reactive schizophrenic, and brain-damaged patients was tested by administering the Object Sorting Test to 125 hospitalized veterans. The diagnostic groups were equivalent in mean education, intelligence, and length of hospitalization, but the tuberculous and brain-damaged patients averaged 8 yr. older than the schizophrenics. None of the scores differentiated the groups at the .05 level. In discussing these results, it was maintained that, contrary to comment in the literature, "conceptual area" has never conclusively differentiated, in a simultaneous comparison, between nonpsychiatric, brain-damaged, and schizophrenic patients, and may not be appropriate for this purpose. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
40.
This paper proposes a basic structured light system for pose estimation. It consists of a circular laser pattern and a camera rigidly attached to the laser source. We develop a geometric modeling that allows to efficiently estimate the pose at scale of the system, relative to a reference plane onto which the pattern is projected. Three different robust estimation strategies, including two minimal solutions, are also presented with this geometric formulation. Synthetic and real experiments are performed for a complete evaluation, both quantitatively and qualitatively, according to different scenarios and environments. We also show that the system can be embedded for UAV experiments.  相似文献   
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