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1.
This work examines the correlation between the 1H‐NMR T2 relaxation constant and the mechanical properties of aged crosslinked polyolefin cable insulation. T2 experiments on unswollen samples could not differentiate between unaged and highly aged materials; all exhibited 1H T2 constants of approximately 0.5 ms. To accentuate the effects of aging, samples were swollen in various solvents. Unaged samples had T2 values of approximately 15 ms in good solvents. With thermal aging, T2 values decreased as the ultimate tensile elongation decreased. However, the correlation between T2 and elongation differed for samples irradiated with high‐energy radiation and for materials aged above versus below the crystalline melting temperature. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2578–2582, 2003 相似文献
2.
Heng Zhang Jack Gromek Gayath W. Fernando Harris L. Marcus Sam Boorse 《Journal of Phase Equilibria》2002,23(3):246-248
The thermal equilibrium decomposition properties of the PdO-Pd system under oxygen partial pressures ranging from 0.1 to 1.0 atm in a total combined pressure of oxygen and nitrogen of 1.0 atm were investigated by means of thermal-gravimetric analyses. The phase diagram of Pd-PdO over the range of oxygen/nitrogen gas concentration was established. The decomposition temperature of PdO to Pd was found to increase with the partial pressure of oxygen. 相似文献
3.
A 55-year-old woman with primary (granulomatous) angiitis of the central nervous system in association with non-Hodgkin's lymphoma (mucosa-associated lymphoid tissue type) presented with an acute spinal subdural hemorrhage secondary to rupture of one of several fusiform inflammatory aneurysms of the spinal cord radicular arteries. The literature on hemorrhagic complications, aneurysms, and spinal cord involvement in granulomatous angiitis is reviewed. Recognition of granulomatous angiitis is important, as the condition may be responsive to immunosuppressive therapy. 相似文献
4.
GA Masters AM Mauer PC Hoffman D Wyka BL Samuels SA Krauss S Watson H Golomb EE Vokes 《Canadian Metallurgical Quarterly》1998,9(6):677-680
PURPOSE: We designed a phase I-II trial of three active agents, paclitaxel, ifosfamide, and vinorelbine, in advanced non-small-cell lung cancer (NSCLC) to: 1) define the dose-limiting toxicities (DLT) and maximum tolerated dose (MTD) of paclitaxel with filgrastim (G-CSF) support; and 2) determine the overall response rate and median survival of patients treated on this regimen. PATIENTS AND METHODS: We treated cohorts of patients with stage IIIB or IV NSCLC with ifosfamide 1.2-1.6 g/m2/day x 3 and vinorelbine 20-25 mg/m2/day x 3 and escalating doses of paclitaxel at 100-175 mg/m2 on day 2 with G-CSF support on a 21-day cycle. One prior experimental single-agent chemotherapy regimen was allowed. RESULTS: Fifty-six patients, were enrolled on this trial: 27 on the phase I portion of the study and an additional 29 at the recommended phase II dose (RPTD). Thirteen patients had received prior chemotherapy. Paclitaxel doses of 175 mg/m2 and 150 mg/m2 produced dose-limiting myelosuppression, and the RPTD was determined to be paclitaxel 135 mg/m2 with ifosfamide 1.2 g/m2/day on days 1-3 and vinorelbine 20 mg/m2/ day on days 1-3 with G-CSF support. The overall response rate was 18%, with a median survival of 6.1 months. Six of 35 patients (17%) treated at the RPTD achieved a partial response to therapy. Grade IV neutropenia was observed in 19 of 35 patients at this dose, with eight patients suffering febrile neutropenia. CONCLUSIONS: This non-cisplatin-containing three-drug regimen has substantial toxicity and low activity in advanced NSCLC, and does not seem to improve on prior regimens. It is unclear whether the lack of efficacy relates to an antagonistic reaction between the specific drugs, administration schedule, or to subtherapeutic doses of the individual agents. 相似文献
5.
The tet(M) genes were characterized from 84 isolates of 10 different bacterial species isolated from the periodontal pockets of 16 patients with periodontal disease. A 740 bp polymerase chain reaction product from the hypervariable region of the tet(M) structural gene was cleaved with the restriction enzymes AluI and HinfI. Three different restriction patterns were identified for each of the two enzymes. By DNA sequencing, using a direct solid-phase automated sequencing method, the isolates could be grouped into 3 different clusters of tet(M) subtypes. The internal DNA homology within each subtype was 98-100%; the homology between clusters was 89-94%. Two different subtypes were identified in 9 of 10 bacterial species, and the remaining species had 3 different subtypes. One of the subtypes (M3) was seen mainly in the anaerobic isolates. This subtype was different from all earlier sequenced structural tet(M) genes present in the Genbank. Most patients had two different subtypes of tet(M), and a third subtype was seen in the 3 patients who exhibited the greatest variety of tetracycline-resistant bacterial species. It appears that the presence of one subtype of the tet(M) gene within a patient or bacterial species does not prevent the acquisition of another subtype of the same gene. This study identified a new subtype of the tet(M) gene and grouped it into 3 distinct yet highly homologous genetic subtypes. 相似文献
6.
JJ Harris DK Lunt SB Smith WL Mies DS Hale M Koohmaraie JW Savell 《Canadian Metallurgical Quarterly》1997,75(4):986-992
Two groups of Brangus steers produced by nuclear transplantation cloning were used in parallel studies investigating the impact of calf- and yearling-feeding. The first group (n = 8) were fed as calves (CF; n = 4) or yearlings (YF; n = 4) to a constant age end point of 16 mo. The second group (n = 10) were fed as calves (CF; n = 5) or yearlings (YF; n = 5) to a constant live weight end point (530 kg). When slaughtered at the same age, CF and YF steers did not differ (P > .05) in feedlot ADG, but the CF steers were heavier and had higher dressing percentages, numeric yield grades, and quality grades (P < .05). Top loin steaks from the groups of steers did not differ (P > .05) in palatability traits. When fed to a constant live weight, the YF steers gained more rapidly (P < .05) and had lower (P < .05) numeric yield grades than did CF steers. Again CF steers had higher (P < .05) dressing percentages. There was no difference (P > .05) between the treatments in carcass quality grade or meat palatability characteristics. Thus, when finished to a constant weight end point, YF steers gained more rapidly, with no adverse effects on carcass quality grade or palatability traits; however, CF steers consistently produced higher dressing percentages, largely due to greater external fatness. 相似文献
7.
We have investigated the visual responses of 184 single units located in the superficial layers of the optic tectum (OT) of the decerebrate, paralysed pigeon. Visual responses were similar to those reported in non-decerebrate preparations; most units responded best to moving visual stimuli, 18% were directionally selective (they had a clear preference for a particular direction of visual stimulus movement), 76% were plane-selective (they responded to movement in either direction in a particular plane). However, we also found that a high proportion of units showed some sensitivity to the orientation of visual stimuli. We examined the effects of extraocular muscle (EOM) afferent signals, induced by passive eye movement (PEM), on the directional visual responses of units. Visual responses were most modified by particular directions of eye movement, although there was no unique relationship between the direction of visual stimulus movement to which an individual unit responded best and the direction of eye movement that caused the greatest modification of that visual response. The results show that EOM afferent signals, carrying information concerning the direction of eye movement, reach the superficial layers of the OT in the pigeon and there modify the visual responses of units in a manner that suggests some role for these signals in the processing of visual information. 相似文献
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