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91.
AL Hughes 《Canadian Metallurgical Quarterly》1999,49(2):106-114
PURPOSE: Because intraperitoneal (i.p.) therapy may provide a therapeutic advantage and because hyperthermia enhances carboplatin (CBDCA) cytotoxicity, we evaluated the feasibility, toxicity, and pharmacokinetics of CBDCA given via continuous hyperthermic peritoneal perfusion (CHPP) in patients with small-volume residual ovarian cancer. Patients and METHODS: Six patients underwent optimal cytoreductive procedures (residual disease < or =5 mm) as initial treatment of stages II and III epithelial ovarian adenocarcinoma. All patients received a 90-min CHPP at a CBDCA dose of 800-1200 mg/m2, with the perfusate being recirculated rapidly from a reservoir through a heat exchanger, resulting in i.p. temperatures of 41-43 degrees C. Plasma, perfusate, and urine samples were collected and platinum was quantified by flameless atomic absorption spectrophotometry. RESULTS: At no time did any patient's core temperature exceed 40 degrees C. Peak perfusate platinum concentrations were 8- to 15-fold higher than peak ultrafilterable plasma concentrations. The permeability-area product was extremely high and variable (14-90 ml/min), resulting in a regional advantage of 1.9-5.3. The percentage of the dose absorbed ranged widely from 27% to 77%. Dose-limiting hematologic toxicity was observed at a dose of 1200 mg/m2 and this was associated with a CBDCA AUC in plasma of 11 mg min ml(-1). CONCLUSION: CHPP with CBDCA was safely given to three patients at a dose of 800 mg/m2, and dose-limiting hematologic toxicities observed at 1200 mg/m2, correlated with the plasma CBDCA exposure established when lower doses of CBDCA are given systemically. The pharmacokinetic data are consistent with the expected effect of vigorous mixing on the exposed peritoneal surface area. Variable drug absorption and clearance make the prediction of systemic exposure highly uncertain. These findings may have important implications for novel therapies given i.p. 相似文献
92.
Douglas A. Spicer Lisa R. Booth Karin A. Hughes Robert J. Kaiser Amy L. Springer 《Journal of The Association for Laboratory Automation》2001,6(2):63
Prolinx,® Inc. of Bothell, WA has developed the RapXtract™ 384 Dye Terminator Removal Kit for full automation of DNA sequencing reaction purification. The RapXtract product line is based upon proprietary superparamagnetic particle technology that eliminates the need for centrifugation, vacuum filtration, or modified primers to achieve purification of sequencing reactions. The kit described here is pre-dispensed in a 384-well microtiter plate and run on the TECAN GENESIS Workstation 150 (Tecan U.S. Inc., Research Triangle Park, NC). This system enables rapid purification of up to 384 sequencing reactions in a single run.As the completion of the Human Genome Project nears, it is imperative for biotechnology and pharmaceutical companies to increase throughput of DNA sequencing in order to be competitive in the drug discovery and validation process. The “race to market” requires a shift from standard DNA sequencing processes-including DNA sequencing reaction purification-towards complete walk-away automation for all steps.Existing sequencing reaction purification methods (Table 1) require considerable resources including: plastic and other laboratory consumables; specialized equipment, such as high-speed centrifuges or vacuum filtration apparatus; and labor-intensive protocols requiring large amounts of technician time. As a result, walk-away automation of standard purification methods is difficult and expensive. 相似文献
93.
DD Lund FM Faraci H Ooboshi BL Davidson DD Heistad 《Canadian Metallurgical Quarterly》1999,30(1):120-125
OBJECTIVE: Regional presynaptic dopaminergic function and its regulation by dopamine agonists in different stages of PD can be measured by L-[11C]dopa and PET. In the current investigation, we studied the effects of therapeutic apomorphine on L-[11C]dopa uptake in patients with early and advanced PD. BACKGROUND: With disease progression and chronic dopamine agonist treatment, motor response complications supervene in a majority of PD patients. It is assumed that both presynaptic and postsynaptic changes in the dopaminergic system act to modify dopaminergic efficacy. METHODS: Patients with early and advanced stages of PD were included in the study. All patients were investigated twice with PET and L-[11C]dopa drug free and during a subsequent standardized therapeutic apomorphine infusion. RESULTS: Subregional analysis of the striatum showed differences in the effects of apomorphine infusion on the L-[11C]dopa influx rate in the two patient categories. In patients with early and uncomplicated PD, apomorphine infusion decreased the L-[11C]dopa influx rate. This decrease was most pronounced in the dorsal part of the putamen. In advanced PD patients, apomorphine did not affect the striatal L-[11C]dopa influx rate. CONCLUSIONS: We suggest that in mild and stable PD an upregulated presynaptic inhibitory feedback regulation, particularly in the dorsal putamen, acts to maintain congruity within the dopaminergic system in response to antiparkinsonian medication. However, this inhibitory feedback regulation is diminished with the progression of nigrostriatal degeneration and chronic dopamine agonist treatment. 相似文献
94.
C. Sampson R. Edmondson J. Keegan S. Humphreys R. Hughes D. Talbot P. Andrews D. Firmin D. Longmore 《Magma (New York, N.Y.)》1994,2(3):315-318
Intimal hyperplasia is the earliest microscopic change detectable in the arterial wall in the development of arteriosclerosis and atherosclerosis. To enable high-resolution imaging of this, a standard 1.5-T machine was modified using inserted gradient coils of 30 cm internal diameter and surface radio-frequency coils. Six rabbit aorta specimens with injury-induced intimal hyperplasia and two normal rabbit aorta specimens were imaged using a spin-echo sequence of TE 40. Pixel sizes as small as 20 µ×20 µ could be obtained and the area of intimal hyperplasia could be measured at 80 µ×40 µ. The results were compared with those made by a computer-linked microscope. In the injured aortas, there was a low-signal region on magnetic resonance imaging which corresponded to the media of the vessel wall when compared with the histology.T
1 andT
2 constants for the media were determined and compared with those of a normal specimen. TheT
1 constant was shorter for the media of the injured aorta than in the normal. This could be related to the disruption of the internal elastic lamina and migration of muscle cells to the intima which occurs following injury. The popliteal artery of four normal volunteers was imaged and the area of the wall could be measured at a pixel size of 312 µ×160 µ. This suggests thatin vivo studies of intimal hyperplasia arteriosclerosis and atherosclerosis could be made. 相似文献
95.
Holmes RB Hughes K Fairchild P Spivey B Smith A 《Journal of the Optical Society of America. A, Optics, image science, and vision》2002,19(3):444-457
Quasi-monochromatic light will form laser speckle upon reflection from a rough object. This laser speckle provides information about the shape of the illuminated object. Further information can be obtained if two colors of coherent light are used, provided that the colors are sufficiently close in wavelength that the interference is also measurable. It is shown that no more than two intensities of two speckle patterns and their interference are required to produce an unambiguous band-limited image of an object, to within an overall spatial translation of the image, in the absence of measurement errors and in the case where all roots of both fields and their complex conjugates are distinct. This result is proven with a root-matching technique, which treats the electric fields as polynomials in the pupil plane, the coefficients of which form the desired complex object. Several root-matching algorithms are developed and tested. These algorithms are generally slow and sensitive to noise. So motivated, several other techniques are applied to the problem, including phase retrieval, expectation maximization, and probability maximization in a sequel paper [J. Opt. Soc. Am. A 19, 458 (2002)]. The phase-retrieval and expectation-maximization techniques proved to be most effective for reconstructions of complex objects larger than 10 pixels across. 相似文献
96.
The early 1990s saw several announcements of commercial shared-memory systems using processors that aggressively exploited instruction-level parallelism (ILP), including the MIPS R10000, Hewlett-Packard PA8000, and Intel Pentium Pro. These processors could potentially reduce memory read stalls by overlapping read latency with other operations, possibly changing the nature of performance bottlenecks in the system. The authors' experience with Rsim demonstrates that modeling ILP features is important even in shared-memory multiprocessor systems. In particular, current simple processor-based approximations cannot model significant performance effects for applications exhibiting parallel read misses. Further, recent shared-memory designs such as aggressive implementations of sequential consistency use the aggressive ILP-enhancing features of modern processors that simple processor-based simulators do not model. As microprocessor systems become more complex, the availability of shared infrastructure source code is likely to become increasingly crucial. The authors plan to release a new Rsim version shortly that will include instruction caches, TLBs, multimedia extensions, simultaneous multithreading, Rabbit fast simulation mode, and ports to Linux platforms 相似文献
97.
Stephane Dassy Hughes Wiame Fernand C. Thyrion 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1994,59(2):149-156
Esterification of lactic acid with butanol catalysed by cation-exchange resin was carried out in a batch reactor in dioxane and toluene. The reaction rate was found to be first order with respect to catalyst and acid concentrations. The inhibiting effect of water and butanol has been evaluated. The rate data were correlated with a kinetic model based on inhibition by water and butanol. 相似文献
98.
99.
There are known 3 likely mechanisms of virus conveyance into the central nervous system (CNS). These include hematogenic penetration, spread along the peripheral nerves, and the olfactory pathway which begins from the infected olfactory neuroepithelial cells. The possibility of viral spread into CNS via the olfactory pathway was shown for the representatives of togaviruses, herpesviruses, coronaviruses, rhabdoviruses, and for some others. This study suggests that the olfactory pathway of viral conveyance into CNS may be blocked by specific mucosal antibodies in the nasal mucosa. The recombinant TK- variant of WR vaccinia strain with inserted genes coding structural and nonstructural proteins of TBE virus is accumulated in the branches of the respiratory tract only while the parenteral vaccinia strain is detected in the brain regions, spleen, respiratory tract, and in blood. The protective activity of recombinant strain and inactivated TBE vaccine after mice immunization by escarification or intranasally, or subcutaneously was comparatively studied. The findings indicate that intranasal immunization by recombinant strain is the most protective against intraperitoneal challenge by TBE virus. The mucosal and humoral immune response that was induced by intranasal immunization seems to provide the highest levels of protection, which was experimentally observed. 相似文献
100.
TF-1/TPO cells are derived from an erythroleukemia cell line, TF-1, and are absolutely dependent on either TPO or granulocyte-macrophage colony-stimulating factor (GM-CSF)/interleukin-3 (IL3) for their continuous growth and survival. To gain insight into the molecular basis of hemopoietic activities shared by TPO and GM-CSF/IL3 in TF-1/TPO cells, we studied the cross-talk between signal transduction pathways elicited by these cytokines. Stimulation of TF-1/TPO cells with TPO resulted in tyrosine phosphorylation of the TPO receptor (c-Mpl) as well as the common beta subunit (beta c) of GM-CSF/IL3 receptor complex. GM-CSF, however, induced tyrosine phosphorylation of beta c but not c-Mpl. TPO-induced tyrosine phosphorylation of beta c was time- and dose-dependent. We next examined whether or not TPO-induced tyrosine phosphorylation of beta c led to recruitment of SH2-containing molecules such as Stat5 and Shc. While GM-CSF caused association of Stat5 and Shc with beta c, TPO caused association of Stat5, but not Shc, with beta c, suggesting that TPO and GM-CSF may not induce phosphorylation of the same sets of tyrosine residues in beta c. These results suggest that activation of c-Mpl affects the signaling pathway of GM-CSF/IL3 but not vice versa. 相似文献