18 research outputs found
Molecular velocity auto-correlation of simple liquids observed by NMR MGSE method
The velocity auto-correlation spectra of simple liquids obtained by the NMR
method of modulated gradient spin echo show features in the low frequency range
up to a few kHz, which can be explained reasonably well by a long
time tail decay only for non-polar liquid toluene, while the spectra of polar
liquids, such as ethanol, water and glycerol, are more congruent with the model
of diffusion of particles temporarily trapped in potential wells created by
their neighbors. As the method provides the spectrum averaged over ensemble of
particle trajectories, the initial non-exponential decay of spin echoes is
attributed to a spatial heterogeneity of molecular motion in a bulk of liquid,
reflected in distribution of the echo decays for short trajectories. While at
longer time intervals, and thus with longer trajectories, heterogeneity is
averaged out, giving rise to a spectrum which is explained as a combination of
molecular self-diffusion and eddy diffusion within the vortexes of hydrodynamic
fluctuations.Comment: 8 pages, 6 figur
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A phase II study to determine the efficacy and tolerability of intravenous ZD9331 in heavily pretreated patients with ovarian cancer
This Phase II, multicenter, open-label study was conducted to assess the efficacy and tolerability of ZD9331, a novel direct-acting thymidylate synthase inhibitor, in heavily pretreated patients with ovarian cancer.
The study recruited 44 women with ovarian cancer or primary peritoneal cancer previously treated with platinum therapy and paclitaxel and with progressive disease after, or intolerance to, topotecan administered as the most recent therapy. ZD9331 was administered as an intravenous infusion at 130 mg/m
2 on Days 1 and 8 of 3-week cycles, until objective evidence of disease progression. A cutoff date of 3 months after the last patient received the first dose was set for data collection.
Patients received a mean of 3.3 cycles of ZD9331 and a total of 143 cycles were administered. Among the 42 patients evaluated for best overall tumor response, one achieved a complete response and two achieved a partial response, giving an objective tumor response rate of 7%. The complete response occurred at Day 15 of Cycle 2 in a patient receiving ZD9331 as her eighth-line therapy. Seven patients had stable disease, giving a disease control rate of 23%. Thirty-one patients (71%) had disease progression and the median time to progression was 53 days. Most patients (89%) experienced drug-related adverse events, most commonly nausea (73%), vomiting (48%), and neutropenia (50%). Six patients (14%) were withdrawn from treatment due to adverse events.
The preliminary evidence of efficacy and acceptable tolerability of ZD9331 in this heavily pretreated population with ovarian cancer warrants further investigation, especially in a less heavily pretreated patient population