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排序方式: 共有399条查询结果,搜索用时 9 毫秒
1.
RP Whitehead J Jacobson TD Brown SA Taylor GR Weiss JS Macdonald 《Canadian Metallurgical Quarterly》1997,15(6):2414-2419
PURPOSE: Pancreatic cancer is difficult to treat, with most patients surgically unresectable at the time of diagnosis. Radiotherapy and chemotherapy can offer palliation, but more effective therapy is needed. This trial evaluated the effects of an aggressive schedule of paclitaxel given with granulocyte colony-stimulating factor (G-CSF) to patients with advanced pancreatic cancer. PATIENTS AND METHODS: All patients were required to have a histologic diagnosis of pancreatic adenocarcinoma with measurable disease and no prior chemotherapy or radiation therapy. Patients had to have performance status of 0 to 2, pretreatment absolute granulocyte count > or = 1,500/microL, and platelet count greater than or equal to the institutional lower limit of normal. Following pretreatment with dexamethasone, diphenhydramine, and cimetidine, patients received paclitaxel at a dose of 250 mg/m2 by 24-hour infusion on day 1, repeated every 21 days. G-CSF was given at a dose of 5 microg/kg/d on days 3 to 18 or until two consecutive absolute neutrophil counts (ANCs) > or = 10,000/microL were obtained. Doses of paclitaxel were modified depending on nadir counts. RESULTS: Forty-five patients were entered onto this study, with six ineligible. For the 39 eligible patients, there was one complete response (CR) and two partial responses (PRs), five stable/no responses, 23 increasing disease, two early deaths, and six patients whose assessment was inadequate to determine response. The response rate was therefore three of 39 or 8% (95% confidence interval [CI], 2% to 21%). The median survival time for the 39 eligible patients was 5 months. The most common toxicities were anemia, leukopenia/granulocytopenia, malaise/fatigue, nausea/vomiting, alopecia, thrombocytopenia, paresthesias, and liver function abnormalities. There was one death due to sepsis. CONCLUSION: Single-agent paclitaxel in this dose and schedule has minimal activity in pancreatic adenocarcinoma patients. 相似文献
2.
The serum amyloid A (SAA) superfamily comprises a number of genes and proteins characterized from a range of mammalian species. The majority of members described to date are dramatically induced during the acute-phase response, suggesting an important short-term beneficial role in the response to tissue injury and inflammation. However, important disease associations have also been proposed for certain SAAs during chronic inflammation. The nomenclature of many of the superfamily members has been the result of comparisons with previously reported sequences implying disease association and/or functional relatedness between such members. The evolutionary relationships of the SAA superfamily members have been investigated by comparisons at both the amino acid and the nucleotide level. The results indicate that all members of the superfamily within a species have been undergoing concerted evolution. This has important implications in ascribing functions and disease associations to individual SAA superfamily members and indicates that designations should not be based on the extent of amino acid identity alone but should be made only following direct experimental observation of the proteins themselves. 相似文献
3.
David C. Whitehead Katherine M. Goulden Roy D. Hartley 《Journal of the science of food and agriculture》1985,36(5):311-318
The distribution of 10 nutrient elements was assessed in three fractions of herbage samples of perennial ryegrass, tall fescue, white clover and lucerne. The cell wall fraction, prepared by mechanical disintegration of undried material, contained the following proportions of the total herbage content of the major elements: N, 2.9–16.4%; P, 3.0–6.9%; S, 3.6–17.2%; Ca, 11.3–51.8%; Mg. 6.4–27.6% and K, 0.1–1.7%. Substantial though more variable proportions of the trace element cations, Fe, Mn, Zn and Cu were also present in the cell wall fraction. The extent to which the elements were soluble in water was assessed by analysis of the water-insoluble fraction prepared from freeze-dried samples of each herbage. The proportions of the total herbage content of the major elements soluble in water were: N, 30–57%; P, 80–92%; S, 35–71%; Ca, 48–69%; Mg. 65–83% and K, 90–96%. With the trace element cations the proportions soluble in water were more variable, though they were generally less than 70% of the total. The extent to which the various elements were soluble in 80% aqueous ethanol was assessed by analysis of the insoluble fraction prepared from freeze-dried materials. With each of the major elements, smaller proportions of the total herbage content were soluble in 80% ethanol than in water, which may reflect in part the lower solubility of proteins and pectin. With the trace element cations, the differences in solubility between 80% ethanol and water were generally small and inconsistent. 相似文献
4.
5.
Time average differential pressure profiles have been recorded at the base of fluidized beds with cross-sectioned areas of 0.375 and 1.5 m2, both being fitted with uniform resistance gas distributors and containing various materials. For beds of a specific material, with equal ratios of defluidized bed depth/bed width (within the limits 0.375 – 1.5), a common relationship was found between the time average differential pressure difference between the centre and corners at the bed base (expressed as a fraction of total theoretical bed pressure drop at incipient fluidizing conditions) and superficial gas velocity. 相似文献
6.
The removal of dichloromethane from atmospheric pressure air streams using plasma-assisted catalysis
Plasma-assisted catalysis was used for the destruction of 500 ppm of dichloromethane, CH2Cl2 (DCM), in gas streams of air using a non-thermal, atmospheric pressure plasma utilising a dielectric packed bed. The combination of plasma and catalyst gave improved destruction of DCM. Eight catalysts which including alumina, TiO2 and various zeolites were investigated with the finding that alumina in a one-stage reactor configuration and TiO2 and HZSM-5 in two-stage configurations gave the best DCM destructions. The sodium zeolites are capable of reducing by 50% the unwanted NOx by-products, formed by plasma processing in air. The nature of the catalyst is important in terms of the destruction efficiency, end-product selectivity and NOx reduction. 相似文献
7.
Studies have been made on the effect of the molecular weight of p-N,N-dimethylaminostyrene homopolymers and the composition of its copolymers with styrene on the glass transition temperature. Comparative thermal degradation studies have been made on polystyrene and p-N,N-dimethylaminostyrene polymers by thermal analytical methods (TG, DTA, and DSC). The differences in thermal stability and overall thermal degradation behavior of the two systems are discussed in terms of the differences in their degradation mechanisms. 相似文献
8.
Highly sensitive detection of neutral Kr atoms was accomplished by the use of laser-induced fluorescence. In one experiment, Kr at 40 parts per 10(12) in He was detected at a signal-to-noise ratio of 500 by time-resolved fluorescence measurements. The Kr metastable 1s(5) level was populated by cascade after two-photon excitation to the 2p(6) level by the frequency-tripled output of a pulsed single-longitudinalmode dye laser. After a delay, when scattered laser light and cascade resonance fluorescence became negligible, trace quantities of Kr were detected by the use of a pulsed-laser pumping scheme. In a related experiment, (78)Kr/(86)Kr isotope ratios ranging from 1 to 0.1 were measured with a resonant isotopic depletion technique first proposed by Makarov [Sov. J. Quantum Electron. 13, 722 (1983)]. The (86)Kr metastable population was selectively depleted by optical pumping to a higher-lying state that relaxed to the ground state by means of radiative cascade. After the (78)Kr/(86)Kr ratio of metastables had been enriched by a factor of 10, the (78)Kr population was probed by pulsed excitation. Premixed (78)Kr/(86)Kr ratios were measured to within an accuracy of 10%, even for unresolved, Doppler-broadened transitions. 相似文献
9.
Just-in-time defect prediction can remind software developers and managers to verify and fix bugs at the moment they appeared, thus improving the effectiveness and validity of bug fixing. Existing studies mainly focus on just-in-time prediction for software files (JIT-F). JIT-F is a binary classification problem, which classifies (hence predicts) a file change as buggy or clean. This article provides a detailed analysis of just-in-time defect prediction for software hunks (JIT-H), which predicts bugs at a finer level of granularity, and hence further improves the efficiency of bug fixing. Classification is performed using the ensemble technique of bagging—aggregated combinations of random under sampling plus multiple classifiers (J48 and Random Forest). An empirical study with 10 open source projects was conducted to validate the effectiveness of JIT-H. Experimental results show that JIT-H is effective at predicting defects in software hunk changes. Compared with JIT-F, JIT-H is more cost effective. Additionally, analysis on the change features indicates that Text Vector features and hunk change level features are of more importance than features in other groups and levels. 相似文献
10.
Ken Maynard Patrick Moss Marcus Whitehead S. Narayanan Matt Garay Nathan Brannon Raj Gopal Kantamneni & Todd Kustra 《Expert Systems》2001,18(2):88-98
Although developments on software agents have led to useful applications in automation of routine tasks such as electronic mail filtering, there is a scarcity of research that empirically evaluates the performance of a software agent versus that of a human reasoner, whose problem-solving capabilities the agent embodies. In the context of a game of a chance, namely Yahtzee©, we identified strategies deployed by expert human reasoners and developed a decision tree for agent development. This paper describes the computer implementation of the Yahtzee game as well as the software agent. It also presents a comparison of the performance of humans versus an automated agent. Results indicate that, in this context, the software agent embodies human expertise at a high level of fidelity. 相似文献