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41.
Virtual instruments for an extracorporeal circulation (ECC) process were developed to simulate the reactions of a patient to different artificial perfusion conditions. The computer simulation of the patient takes into account the hydraulic, volume, thermal and biochemical phenomena and their interaction with the devices involved in ECC (cannulae dimensions, oxygenator and filter types, pulsatile or continuous pump and thermal exchangers). On the basis of the patient's initialisation data (height, weight, Ht) and perfusion variables (pump flow rate, water temperature, gas flow rate and composition) imposed by the operator, the virtual ECC monitors simulated arterial and venous pressure tracings in real time, along with arterial and venous flow rate tracings, urine production tracing and temperature levels. Oxyhemoglobin arterial and venous blood saturation together with other related variables (pO2, pCO2, pH, HCO3 are also monitored. A drug model which allows the simulation of the effect of vasodilator and diuretic drugs is also implemented. Alarms are provided in order to check which variables (pressure, saturation, pH, urine flow) are out of the expected ranges during the ECC simulation. Consequently the possibility of modifying the control parameters of the virtual devices of the ECC in run-time mode offers an interaction mode between the operator and the virtual environment. 相似文献
42.
The EU Concerted Action Workshop on 11q23 Abnormalities in Hematological Malignancies collected 550 patients with abnormalities involving 11q23. Of these, 53 patients had a translocation involving chromosome 11, breakpoint q23, and chromosome 19, breakpoint p13. Karyogram review enabled each patient to be further defined as t(11;19)(q23;p13.1) (21 patients) or t(11;19)(q23;p13.3) (32 patients). There was a marked difference between the type of banding and the translocation identified: t(11;19)(q23;p13.1) was detected predominantly by R-banding, whereas t(11;19)(q23;p13.3) was detected almost solely by G-banding. Additional change was extremely rare in patients with t(11;19)(q23;p13.1) but occurred in nearly half of the patients with t(11;19)(q23;p13.3). Patients with t(11;19)(q23;p13.1) all had leukemia of a myeloid lineage, mostly acute myeloid leukemia (AML), and were predominantly adult. In contrast patients with t(11;19)(q23;p13.3) had malignancies of both myeloid and lymphoid lineage and were mainly infants less than 1 year old. The survival of both groups of patients was generally poor, over 50% of t(11;19)(q23;p13.1) patients died within 2 years of diagnosis and the median survival of acute lymphoblastic leukemia (ALL) patients with t(11;19)(q23;p13.3) was 17.6 months. 相似文献
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44.
The aim of this study was to establish the feasibility, evaluate the response rate, and assess the impact on local control and survival in locally advanced (bulky nodal) squamous cell carcinoma of the head and neck (SCCHN) patients treated with neoadjuvant chemotherapy consisting of cisplatin followed by continuous infusion of vindesine and fluorouracil with intermittent i.v. folinic acid. Eligibility criteria included histologically proven SCCHN, previously untreated locally advanced stage III-IV with measurable or evaluable disease, no distant metastases, an Eastern Cooperative Oncology Group (ECOG) performance status of less than 2, patient age of at least 18 years, and adequate bone marrow, hepatic, and renal functions. The protocol consisted of three cycles (day 1, day 21, day 42) of Cisplatin (CDDP) 100 mg/m2/day i.v. on day 1 immediately followed by 4 days (96 h) of continuous infusion of vindesine 0.8 mg/m2/day and 5-fluorouracil (5-FU) 600-700 mg/m2/day with folinic acid 150 mg/m2 i.v. every 6 h x 16 doses before locoregional treatment with radiotherapy preceded by radical surgery when appropriate. Twenty-nine patients were enrolled in this study, and 28 were evaluable for activity; an objective response rate of 55% (four complete responses, 12 partial responses) was achieved. Leukopenia and mucositis were the most frequent and severe toxicities. The addition of vindesine did not improve the activity of the CDDP-FU-folinic acid combination, but this may be partly because of the particularly poor prognosis of the present patient population, with 75% of stage IV bulky nodal disease (N2c-N3). 相似文献
45.
Multilayer coatings have been produced using unbalanced magnetron physical vapour deposition in which discrete layers of TiN and ZrN were co-deposited. It has been shown that the multilayers exhibited two-fold periodicity having values of 13 and 2.8 nm. This periodicity, measured both by cross-sectional transmission electron microscopy and low-angle X-ray diffraction, has been precisely related to the process parameters used. Analysis has shown that a third, previously unreported, phase existed within the coating having a lattice parameter comparable to that of TiN and a well-defined orientation relationship with the primary phases. The existence of this phase has been explained in terms of variations in the stoichometry of the coating due to non-uniform metal to nitrogen deposition rates within the chamber. Textural studies revealed that preferred orientation existed in the coating; the degree of which was greater in the ZrN layers than the TiN layers. 相似文献
46.
AH Bosworth MK Williams KA Albrecht R Kwiatkowski J Beynon TR Hankinson CW Ronson F Cannon TJ Wacek EW Triplett 《Canadian Metallurgical Quarterly》1994,60(10):3815-3832
The construction of rhizobial strains which increase plant biomass under controlled conditions has been previously reported. However, there is no evidence that these newly constructed strains increase legume yield under agricultural conditions. This work tested the hypothesis that carefully manipulating expression of additional copies of nifA and dctABD in strains of Rhizobium meliloti would increase alfalfa yield in the field. The rationale for this hypothesis is based on the positive regulatory role that nifA plays in the expression of the nif regulon and the fact that a supply of dicarboxylic acids from the plant is required as a carbon and energy source for nitrogen fixation by the Rhizobium bacteroids in the nodule. These recombinant strains, as well as the wild-type strains from which they were derived, are ideal tools to examine the effects of modifying or increasing the expression of these genes on alfalfa biomass. The experimental design comprised seven recombinant strains, two wild-type strains, and an uninoculated control. Each treatment was replicated eight times and was conducted at four field sites in Wisconsin. Recombinant strain RMBPC-2, which has an additional copy of both nifA and dctABD, increased alfalfa biomass by 12.9% compared with the yield with the wild-type strain RMBPC and 17.9% over that in the uninoculated control plot at the site where soil nitrogen and organic matter content was lowest. These increases were statistically significant at the 5% confidence interval for each of the three harvests made during the growing season. Strain RMBPC-2 did increase alfalfa biomass at the Hancock site; however, no other significant increases or decreases in alfalfa biomass were observed with the seven other recombinant strains at that site. At three sites where this experiment was conducted, either native rhizobial populations or soil nitrogen concentrations were high. At these sites, none of the recombinant strains affected yield. We conclude that RMBPC -2 can increase alfalfa yields under field conditions of nitrogen limitation, low endogenous rhizobial competitors, and sufficient moisture. 相似文献
47.
Home ownership has been associated with health, social and economic benefits. However, a decline in ownership has been observed over the past decade in New Zealand. Minority groups, including Pacific people, have been disadvantaged in the housing sector. This study investigated housing tenure and the relationship between tenure and health among mothers of a birth cohort of Pacific children in New Zealand. Findings showed that most families lived in state or private rental accommodation with few (15.4 per cent) owning their own homes. Homeowners were more likely to be older, partnered and have higher incomes. Better mental health was observed for homeowners compared to renters. Findings can inform housing and public health policy for Pacific families. 相似文献
48.
49.
Williams Paula G.; Wasserman Michelle S.; Lotto Andrew J. 《Canadian Metallurgical Quarterly》2003,22(1):3
In 2 studies, the relation between measures of self-assessed health (SAH) and automatic processing of health-relevant information was investigated. In Study 1, 84 male and 86 female undergraduate students completed a modified Stroop task. Results indicated that participants with poorer SAH showed enhanced interference effects for illness versus non-illness words. In Study 2, 27 male and 30 female undergraduate students completed a self-referent encoding task. Results offered a conceptual replication and extension of Study 1 by confirming the specificity of the relation between SAH measures and automatic processing of health (vs negative or positive general trait) information. These studies provide evidence that individual differences in SAH are reflected in schematic processing of health-relevant information. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
50.
The transmission-reflection method is modified for measuring constitutive parameters of thin high-loss materials used as radar absorbers. The method uses a two-layer structure, consisting of a layer of thin flexible unknown material supported by a thicker rigid known material. The analysis and measurements focus on nonmagnetic samples of a high dielectric constant and loss factor and on the waveguide configuration in the X-band. A nonlinear least-squares optimization is used to obtain the complex permittivity from the measured scattering parameters. The uncertainty analysis presented facilitates selection of the support layer thickness. Simulations with the finite-difference time-domain method explore the effects of sample imperfections. Accuracy of a few percent can be achieved for a sample thickness of a fraction of a millimeter, provided that the thickness of the support dielectric is close to optimum and sample has only small surface imperfections. 相似文献