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101.
102.
DA Black 《Canadian Metallurgical Quarterly》1997,11(4):344-346
RT-PCR method was used to detect the expression level of multi-drug resistance gene (MDR1) and multi-drug resistance associated protein (MRP) in patients with malignant blood disease, including 19 cases of acute leukemia and 6 cases of multiple myeloma. The results showed: expression level of MDR1 in patients with known clinical drug resistance elevated obviously and was significantly associated with clinical drug resistance (r = 0.612, P < 0.01), which indicated that expression of MDR1 was the main mechanism of clinical drug resistance. There is no obvious relationship between expression level of MDR1 and MRP (r = 0.035, P > 0.05). 相似文献
103.
Refactoring Tools: Fitness for Purpose 总被引:1,自引:0,他引:1
Refactoring tools can improve the speed and accuracy with which developers create and maintain software—but only if they are used. In practice, tools are not used as much as they could be; this seems to be because sometimes they do not align with the refactoring tactic preferred by most programmers, a tactic the authors call "floss refactoring." They propose five principles that characterize successful floss-refactoring tools—principles that can help programmers to choose the most appropriate refactoring tools and also help toolsmiths to design tools that fit the programmer's purpose. 相似文献
104.
M de Abood Z de Castillo F Guerrero M Espino KL Austin 《Canadian Metallurgical Quarterly》1997,56(5):313-316
Forty-three homozygous (SS) female sickle cell anemic patients with a history of at least one painful crisis per month and desiring a reversible contraceptive were administered DMPA/3 months or Microgynon monthly. A third group of 16 surgically sterilized patients served as control. Patients were followed for 1 year to assess possible effects of the contraceptives on the patients' painful crises. No changes were observed in any of the groups in the hematological parameters. At the end of the study, 70% of the patients receiving DMPA were pain-free and only 16% of those still reporting painful crises rated them as intense. Patients receiving Microgynon also had an amelioration of the painful crises, although at a lower rate; after 12 months, 45.5% still experienced some crises. Although less marked than in the other groups, 50.5% of the control patients also reported an improvement of their painful crisis, which may be a result of closer medical care. 相似文献
105.
Two species of Pseudomonas capable of utilizing nitroglycerin (NG) as a sole nitrogen source were isolated from NG-contaminated soil and identified as Pseudomonas putida II-B and P. fluorescens I-C. While 9 of 13 laboratory bacterial strains that presumably had no previous exposure to NG could degrade low concentrations of NG (0.44 mM), the natural isolates tolerated concentrations of NG that were toxic to the lab strains (1.76 mM and higher). Whole-cell studies revealed that the two natural isolates produced different mixtures of the isomers of dinitroglycerol (DNG) and mononitroglycerol (MNG). A monomeric, flavin mononucleotide-containing NG reductase was purified from each natural isolate. These enzymes catalyzed the NADPH-dependent denitration of NG, yielding nitrite. Apparent kinetic constants were determined for both reductases. The P. putida enzyme had a Km for NG of 52 +/- 4 microM, a Km for NADPH of 28 +/- 2 microM, and a Vmax of 124 +/- 6 microM x min(-1), while the P. fluorescens enzyme had a Km for NG of 110 +/- 10 microM, a Km for NADPH of 5 +/- 1 microM, and a Vmax of 110 +/- 11 microM x min(-1). Anaerobic titration experiments confirmed the stoichiometry of NADPH consumption, changes in flavin oxidation state, and multiple steps of nitrite removal from NG. The products formed during time-dependent denitration reactions were consistent with a single enzyme being responsible for the in vivo product distributions. Simulation of the product formation kinetics by numerical integration showed that the P. putida enzyme produced an approximately 2-fold molar excess of 1,2-DNG relative to 1,3-DNG. This result could be fortuitous or could possibly be consistent with a random removal of the first nitro group from either the terminal (C-1 and C-3) positions or middle (C-2) position. However, during the denitration of 1,2-DNG, a 1.3-fold selectivity for the C-1 nitro group was determined. Comparable simulations of the product distributions from the P. fluorescens enzyme showed that NG was denitrated with a 4.6-fold selectivity for the C-2 position. Furthermore, a 2.4-fold selectivity for removal of the nitro group from the C-2 position of 1,2-DNG was also determined. The MNG isomers were not effectively denitrated by either purified enzyme, which suggests a reason why NG could not be used as a sole carbon source by the isolated organisms. 相似文献
106.
Karim A. Black K.A. Abraham P. Lofgreen D. Chiu Y.J. Piprek J. Bowers J.E. 《Photonics Technology Letters, IEEE》2000,12(11):1438-1440
We report 85/spl deg/C continuous-wave electrically pumped operation of a 1528-nm vertical-cavity laser. An InP-InGaAsP active region was wafer bonded to the GaAs-AlGaAs mirrors, with a superlattice barrier to reduce the defect density in the active region. 相似文献
107.
Harriet Black Nembhard Ming Shu Kao 《Quality and Reliability Engineering International》2001,17(4):307-321
Nonconforming parts are often produced when a process moves from one level to another due to transition events. Control charting, when applied to a stable state process, is an effective monitoring tool to continuously check for process shifts or upsets. However, the presence of transition events can impede the normal performance of traditional control chart with increased false alarms. The presence of autocorrelation also requires modification to the control charting procedure. We present a methodology for characterizing the process transition which involves a tracking signal statistic, based on the forecast‐based exponentially weighted moving average (EWMA). This test will supplement the forecast‐based EWMA control charting as a means of detecting when the transition event is complete. Such a procedure facilitates smooth application of the appropriate control chart by knowing when the transition is over. The transition characterization methodology also carries benefits in cost and material savings. We use a color transition process in plastic extrusion to illustrate a transition event and demonstrate our proposed methodology. Simulation is employed to evaluate the performance of the methodology. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
108.
The shared use of general-purpose uniprocessors is examined. Support for common uniform-memory-access architectures that have all memory equidistant from all processors in terms of access time is emphasized. This work is also applicable to non-uniform-memory-access machines, whose memory access times depend on the physical distance between the processor and the accessed memory, but it does not provide a complete solution to load-balancing problems for this class of machine. The discussion covers time-sharing scheduling, the Mach scheduler, programming models, scheduling concurrency support, processor allocation, and related work 相似文献
109.
Bernard C. Jung Senior Member IIE J. T. Black Senior Member IIE David W. H. Chen James N. Hool Senior Member IIE 《IIE Transactions》1991,23(2):169-184
Taguchi-based methodology is implemented to determine and to optimize a robot's process capability (RPC). This low-cost solution optimizes a robot's operational conditions. The experiment determines the RPC (i.e., accuracy, repeatability, reproducibility and stability) and considers seven operational factors (i.e., load, speed, distance, orientation, direction, height, and starting point) with three levels each. The results from Taguchi experimental design and data analysis show that the various factors affect each RPC characteristic differently. Therefore, an optimized combination of operational factors for each RPC characteristic is determined separately. Based on the project results, recommendations are made to use Taguchi Methods. Test results and future research needs are also discussed 相似文献
110.
Gerard E. O’Connor Jeffrey Evans Scott Black Neil Fettell Beverley Orchard Ron Theo 《Nutrient Cycling in Agroecosystems》2010,86(2):269-286
Nitrate is known to accumulate under legume crops. The effects of legume crop, inoculation, row width, sowing rate, sowing
date, and intra-cropping with wheat, on the amount and soil distribution of mineral N, residual soil water, crop biomass and
crop N were studied at Wagga Wagga in south-east Australia. After removal of most of the above-ground plant material, the
treatment effects on the biomass, N content, grain yield and grain N of wheat, established in the following season, were also
measured. In a later experiment at Wagga, the recovery of 15N applied to the mid-row of lupin crops established at three row
widths was estimated at crop maturity. At Condobolin, row width effects on the soil distribution of mineral N, biomass, N
accumulation and N fixation of crop legumes and cereals, were determined. At physiological maturity, at Wagga Wagga, very
little nitrate was left beneath cereals. Significantly more was left under legume crops, mostly below 30 cm of soil depth,
and it was distributed differently depending on crop, inoculation, and sampling location. More nitrate was left under pea
and faba than under lupin, and in response to inoculation. Mixing wheat with narrow-leaf lupin did not prevent nitrate accumulation
in soil. For most of the legumes more nitrate was left in the mid-row than in the in-row; and more nitrate was left at the
mid-row of lupin crops sown with wider rows. The additional nitrate left with wider rows increased the growth, N content,
grain yield and protein of wheat established in the following season. 15N labelled nitrate applied mid-row was used less effectively
by lupin as row width increased, in a dry season. At Condobolin, lupin established with wide rows used less soil nitrate than
with narrower rows but maintained crop N by increased N fixation. In contrast, field pea maintained N demand by increasing
nitrate uptake at intermediate row spacing. The study shows that the amount of nitrate accumulated in soil during legume cropping
is susceptible to agronomic management, particularly crop selection, row width and inoculation; and that variation in the
amount of this nitrate may carry forward to impact wheat production in the follow-on season. 相似文献