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1.
Infantile osteopetrosis is a lethal disorder resulting from a severe defect in the ability of osteoclasts to resorb bone. The only therapy shown to be capable of providing lasting benefit is allogeneic hematopoietic stem cell transplantation (HCT). We report the outcome of 10 patients with infantile malignant osteopetrosis treated with HCT from an HLA A, B, DRB1 matched (n=6) or A or B locus mismatched (n=4) family member or unrelated donor at the University of Minnesota between 1978 and 1997. Eight of 10 patients achieved primary engraftment; secondary graft failure was seen in two patients. Five of 10 patients survive; three with full or partial donor chimerism and two with autologous hematological recovery. Transient or partial donor chimerism can be sufficient to correct the hematological manifestations of osteopetrosis. We recommend early referral for consideration of HCT with a related or unrelated donor as neurosensory manifestations of osteopetrosis are generally not reversible. Donor engraftment may be easier to achieve early in the course of the disease. 相似文献
2.
Chen O.T.-C. Sandy Wang Yi-Wen Wu 《Very Large Scale Integration (VLSI) Systems, IEEE Transactions on》2003,11(3):418-433
This work presents low-power 2's complement multipliers by minimizing the switching activities of partial products using the radix-4 Booth algorithm. Before computation for two input data, the one with a smaller effective dynamic range is processed to generate Booth codes, thereby increasing the probability that the partial products become zero. By employing the dynamic-range determination unit to control input data paths, the multiplier with a column-based adder tree of compressors or counters is designed. To further reduce power consumption, the two multipliers based on row-based and hybrid-based adder trees are realized with operations on effective dynamic ranges of input data. Functional blocks of these two multipliers can preserve their previous input states for noneffective dynamic data ranges and thus, reduce the number of their switching operations. To illustrate the proposed multipliers exhibiting low-power dissipation, the theoretical analyzes of switching activities of partial products are derived. The proposed 16 /spl times/ 16-bit multiplier with the column-based adder tree conserves more than 31.2%, 19.1%, and 33.0% of power consumed by the conventional multiplier, in applications of the ADPCM audio, G.723.1 speech, and wavelet-based image coders, respectively. Furthermore, the proposed multipliers with row-based, hybrid-based adder trees reduce power consumption by over 35.3%, 25.3% and 39.6%, and 33.4%, 24.9% and 36.9%, respectively. When considering product factors of hardware areas, critical delays and power consumption, the proposed multipliers can outperform the conventional multipliers. Consequently, the multipliers proposed herein can be broadly used in various media processing to yield low-power consumption at limited hardware cost or little slowing of speed. 相似文献
3.
The purpose of this study was to determine if prostate specific antigen density (PSAD) is a predictor of outcome following external beam radiotherapy for prostate cancer, and to compare it with other prognostic factors. Between January 1990 and December 1993, 205 patients with T1-T3 adenocarcinoma of the prostate received a radical course of external beam irradiation, with no prior or adjuvant hormonal therapy. All patients had pre- and post-treatment serum prostate specific antigen (PSA) evaluation. They were followed up for at least 24 months. PSAD was defined as the ratio of pre-treatment serum PSA to the prostate volume, as determined from CT treatment planning scans. Prostate volumes were calculated using the prostate ellipse formula. Median PSA density was 0.37, with a range 0.01-6.7. Biochemical failure was defined as three consecutive rises in serum PSA, regardless of the magnitude of elevation. 4-year biochemical disease-free survival (BDFS) for patients with PSAD < or = 0.3 was 60%, compared with 22% for patients with PSAD > 0.3 (p = < 0.001). In a multivariate analysis, pre-treatment PSA (p = < 0.001), Gleason score (p = 0.002), and stage (p = 0.03) were independent predictors of BDFS, while PSAD was not an important prognosticator (p = 0.62). Pre-treatment serum PSA is the most important prognosticator of BDFS, following external beam radiotherapy, for patients with prostate cancer. PSA density did not predict treatment outcome. 相似文献
4.
At a dam in Australia the concrete shows a widespread reaction that has caused surface cracking, and possibly a tightening up of gates that control the flow of water through diversion tunnels. The reaction has produced reaction rims to the aggregate, a crystallization of zeolite A-like material within the aggregate and in pores in the concrete, in addition to the precipitation of amorphous alkali-silicate hardened gel in other concrete pores. The hardened gel is sometimes associated with trona and is metastable. It tends to transform into zeolite A-like material or analcite. The reaction products are low in alumina and high in silica. Possible reaction mechanisms are discussed. 相似文献
5.
In 3 experiments the authors examined changes in successive exemplar generation percentages within categories defined semantically (e.g., fruit-P, fruit-A, fruit-M) and by 1st letter (e.g., insect-C, sport-C, car-C), with a mixed control condition (e.g., fruit-P, insect-C, disease-M). Retrieval success declined across 12 successive items in both semantic and letter categories, with no change for the mixed condition. This retrieval inhibition is unrelated to taxonomic frequency of exemplars within either letter or semantic categorical structures. Furthermore, semantic retrieval inhibition appears to be long lasting, suggested by the decline in retrieval percentage across successive 12-item blocks in both the mixed and letter conditions. The authors suggest that different mechanisms underlie the inhibition found in the semantic (suppression) and letter (interference) conditions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
6.
In this paper, we consider the on-line scheduling of jobs that may be competing for mutually exclusive resources. We model the conflicts between jobs with a conflict graph, so that the set of all concurrently running jobs must form an independent set in the graph. This model is natural and general enough to have applications in a variety of settings; however, we are motivated by the following two specific applications: traffic intersection control and session scheduling in high speed local area networks with spatial reuse. Our results focus on two special classes of graphs motivated by our applications: bipartite graphs and interval graphs. The cost function we use is maximum response time. In all of the upper bounds, we devise algorithms which maintain a set of invariants which bound the accumulation of jobs on cliques (in the case of bipartite graphs, edges) in the graph. The lower bounds show that the invariants maintained by the algorithms are tight to within a constant factor. For a specific graph which arises in the traffic intersection control problem, we show a simple algorithm which achieves the optimal competitive ratio. 相似文献
7.
Case Study – The Making of an Institutional Crisis: The Mass Release of Inmates by a Correctional Agency
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A US state correctional agency inadvertently released a large numbers of inmates before expiration of their sentences. This created an institutional crisis, for three reasons. First, the correctly timed release of inmates is unequivocally central the agency's core mission. Second, the early releases were consequential, in that serious crimes were committed by those only out of prison because of early release. Third, a citizen alerted the agency of an early‐release calculation for a particular offender, but the agency failed to act on this information. The correctional agency responded to this crisis by changing both its operating procedure and its culture. 相似文献
8.
Consultants, in competing for work through two-envelope fee tendering, have been urged to consider variability differences between fees and technical scores, since the criterion with the greatest variability will influence which consultant is awarded the contract. Fee and technical score variability arising from different client fee tendering competitions is analysed in this paper, and a method proposed for determining whether a particular client's two-envelope fee tendering competition is likely to be dominated in terms of technical score or fee. Such information should be useful to consultants, as part of their bidding strategy, in deciding whether to aim for a higher technical score or submit a lower fee. Standard deviation is used to measure fee and technical score variability. Fee and technical score standard deviations are determined for each tendering competition, expressed as a ratio and aggregated over a series of competitions. A technical score-fee standard deviation ratio approximately equal to unity indicates that for future competitions consultants should adopt a balanced bidding strategy in putting equal emphasis on fee and technical score. A smaller ratio indicates that consultants should adopt a ‘low fee’ strategy whereas a larger ratio shows that consultants should adopt a ‘high technical score’ strategy. Fee tendering data from two large Hong Kong public sector clients were analysed. Fees were found to dominate the vast majority of tendering competitions, thereby indicating that consultants would be wise to adopt a low fee strategy in future competitions. 相似文献
9.
Plant sources of omega-3 fatty acids (FA) are needed that can materially raise tissue levels of long-chain omega-3 FA [i.e.,
eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (DHA; 20:6n-3)]. Stearidonic acid (SDA; 18:4n-3) is the delta-6
desaturase product of alpha-linolenic acid (ALA; 18:3n-3), and when fed to humans, increases red blood cell (RBC) content
of EPA to a greater extent than does ALA. This study was undertaken to determine the dose-dependence and time course of the
increase in the EPA and DHA content of the heart and RBC in dogs. Adult male Beagles were fed 21, 64, or 193 mg/kg of SDA
in in their food daily for up to 12 weeks. Positive and negative controls were given EPA (43 mg/kg) or high oleic acid sunflower
oil, respectively. The baseline EPA content of RBC was 0.38 ± 0.03% which increased (P < 0.01) in a dose-dependent manner, with the high dose of SDA and EPA achieving levels of 1.33 ± 0.26 and 1.55. ± 0.28%,
respectively. In the heart, the content of EPA rose from 0.06 ± 0.01 to 1.24 ± 0.22% in the EPA group and to 0.81 ± 0.32%
in the high SDA group (both P < 0.01). In both tissues, DHA did not change. Compared to dietary EPA, SDA was 20–23% as efficient in raising tissue EPA
levels. In conclusion, SDA supplementation increased the EPA content of RBC and heart and may have utility as a plant-based
source of omega-3 FA. 相似文献
10.