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31.
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RM Pokorny WR Wrightson RK Lewis KJ Paris A Hofmeister R LaRocca SR Myers D Ackerman S Galandiuk 《Canadian Metallurgical Quarterly》1997,40(12):1414-1420
PURPOSE: Preoperative radiation with combined chemotherapy is effective in shrinking advanced rectal cancer locally and facilitating subsequent surgery. Suppository delivery of 5-fluorouracil is associated with less toxicity and higher rectal tissue concentrations than intravenous administration. This prompted us to evaluate suppository and intravenous administration of 5-fluorouracil and mitomycin C with concomitant radiation to determine associated toxicity. METHODS: Rectal, liver, lymph node, and lung tissue and systemic and portal blood were collected serially from male Sprague Dawley rats to determine drug concentrations following suppository or intravenous delivery of 5-fluorouracil or mitomycin C. Thirty-six animals were randomly assigned to treatment groups and received 5-fluorouracil suppositories, mitomycin C suppositories, or an equivalent intravenous dose of 5-fluorouracil or mitomycin C 30 minutes before radiation therapy. Before and 3, 6, 10, and 15 days following this treatment, blood was collected, colonoscopy was performed, and rectal tissue was harvested for histologic examination. RESULTS: Mitomycin C suppository was significantly less toxic compared with intravenous delivery, and higher rectal tissue concentrations were observed from 10 to 30 minutes (P < 0.05). Compared with intravenous 5-fluorouracil administration and radiation, 5-fluorouracil suppository and radiation resulted in additive myelosuppression at day 6 (P < 0.05) with rapid recovery. CONCLUSIONS: 5-Fluorouracil and mitomycin C suppository delivery combined with radiation causes less systemic toxicity and is more effective than intravenous administration. 相似文献
33.
Diner D.J. Beckert J.C. Reilly T.H. Bruegge C.J. Conel J.E. Kahn R.A. Martonchik J.V. Ackerman T.P. Davies R. Gerstl S.A.W. Gordon H.R. Muller J.-P. Myneni R.B. Sellers P.J. Pinty B. Verstraete M.M. 《Geoscience and Remote Sensing, IEEE Transactions on》1998,36(4):1072-1087
The Multi-angle Imaging SpectroRadiometer (MISR) instrument is scheduled for launch aboard the first of the Earth Observing System (EOS) spacecraft, EOS-AM1. MISR will provide global, radiometrically calibrated, georectified, and spatially coregistered imagery at nine discrete viewing angles and four visible/near-infrared spectral bands. Algorithms specifically developed to capitalize on this measurement strategy will be used to retrieve geophysical products for studies of clouds, aerosols, and surface radiation. This paper provides an overview of the as-built instrument characteristics and the application of MISR to remote sensing of the Earth 相似文献
34.
Developmental differences in the relative salience of features in concept representations in semantic memory and their contributions to differences in cued recall were examined in two experiments. For second graders, fifth graders, and college students, acquisition encoding of cue–target noun pair information was constrained by means of defining-, characteristic-, category-, and incidental-feature orienting questions. At retrieval, the encoding of cue information alone was constrained (Experiment 1) within subjects by means of the same (e.g., defining at acquisition and defining at retrieval) or related (e.g., defining at acquisition and characteristic at retrieval) retrieval questions or was unconstrained (Experiment 2). In both experiments, the acquisition presentation duration was manipulated (1 s or 5 s) in order to examine the spread of feature activation within concepts. The results showed that recall varied with feature salience, with the salience greatest for defining features. In addition, the results suggested that the relative salience of defining features was at least as great for the children as for the adults. The results offer no support for Keil and Batterman's (1984) hypothesis of a shift from characteristic to defining features in the development of word meaning representation in memory. (21 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
35.
Workload measurement is necessary for laboratory management and planning. Adaptation of the College of American Pathologists' scheme to the requirements of a large clinical microbiology laboratory is described. Our method of applying basic work values is simpler and the calculation of workload is easily adapted to take account of alterations in laboratory method. The resulting system of workload measurement can be instituted without undue effort. 相似文献
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The issues of skill specificity and transfer of training were examined from an aptitude–treatment interaction approach. The current investigations extended A. M. Sullivan's (1964) approach by using a procedural transfer task and training conditions that differed in amount of training task practice and the degree of training task similarity to the transfer task. Two experiments were conducted with 232 college students. Experiment 1 examined the effects of a length-of-training manipulation on reasoning ability and transfer task performance relationships, and on the amount of transfer. Experiment 2 evaluated the effects of 2 training tasks that differed in terms of similarity to the transfer task on ability-performance relationships and the amount of transfer. Results suggest that Sullivan's approach partially generalizes to the acquisition of procedural knowledge. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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John F. Ackerman 《Materials Research Bulletin》1982,17(7):883-886
We demonstrate that the replacement of oxygen by fluorine in Sillen's phases is not limited only to BiOCl-type materials. It is possible to prepare PbBiO2Cl-type compounds of general formula APbF2X (A = Li, Na,K, X = Cl, Br, I). Crystal chemistry relations are examined. 相似文献
40.
The second- and third-order harmonic distortion in distributed feedback (DFB) lasers is simulated using a time domain large signal dynamic model. The effects of the longitudinal spatial hole burning, nonlinear gain, spontaneous emission, and current leakage are included in the model. Composite second-order (CSO) and composite triple beat (CTB) are calculated for an 80 channel 60-540 MHz system with 3% modulation depth in each channel. The simulation results are compared with the experimental harmonic distortion measurements 相似文献