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91.
92.
NJ Meropol M Porter LE Blumenson MJ Lindemann RP Perez L Vaickus GM Loewen PJ Creaven KA Wilkes MA Giedlin MA Caligiuri 《Canadian Metallurgical Quarterly》1996,2(4):669-677
We aimed to determine the toxicity and immunological effects of daily s.c. administered low-dose interleukin (IL) 2. Adult cancer patients received a single daily s.c. injection of IL-2 as outpatients for 90 consecutive days. Cohorts of four to nine patients were treated at escalating IL-2 dose levels until the maximum tolerated dose (MTD) was defined. Peripheral blood mononuclear cell phenotyping, IL-2 serum levels, and the presence of anti-IL-2 antibodies were investigated. Thirty-eight patients were treated at seven IL-2 dose levels ranging from 0.4 to 1.75 million International Units (mIU)/m2 daily. The MTD was 1.25 mIU/m2, with constitutional side effects, vomiting, and hyperglycemia dose limiting. Severe toxicity did not occur at or below the MTD, although mild local skin reaction and mild constitutional side effects were common. Objective tumor regressions were not observed during this Phase I trial. Low-dose IL-2 resulted in natural killer (NK) cell (CD3(-) CD56(+)) expansion at all dose levels. This effect was dose dependent (P < 0.01), ranging from a 154 to 530% increase over baseline. Peak NK levels were achieved at 6-8 weeks and sustained through 12 weeks of therapy. As predicted by in vitro studies of IL-2 receptor structure-activity relationships, the subset of NK cells that constitutively express high-affinity IL-2 receptors (CD3(-)CD56(bright+)) showed more profound dose-dependent expansion, with increases ranging from 368 to 2763% (P = 0.015). NK expansion occurred at peak IL-2 levels <10 pM (2.3 IU/ml). Three patients developed nonneutralizing anti-IL-2 antibodies. Thus, we concluded that selective expansion of NK cells may be achieved in vivo with daily s.c. injections of low-dose IL-2 with minimal toxicity. 相似文献
93.
NJ Yousif WW Dzwierzynski JR Sanger HS Matloub 《Canadian Metallurgical Quarterly》1998,102(7):2431-2435
This case report describes the use of a single lateral arm flap sequentially transferred to two defects in a bilateral hand injury. We believe this is a novel approach in reconstructing defects in bilateral hands when a staged reconstruction is planned. 相似文献
94.
A chemical study of the common Caribbean sea plume Pseudopterogorgia acerosa from Puerto Rico has produced two previously undescribed secondary metabolites. One of them, 1, is a new representative of the pseudopterane family of diterpenes possessing the uncommon 3,4;5,6 diepoxyfuran moiety. The other metabolite, 2, is a rare norcembranolide diterpene. Their chemical structures, including relative stereochemistry, were established by detailed analysis of the spectral data in addition to NMR spectral comparisons with known pseudopterane and cembrane models. 相似文献
95.
AJ Bird JS Turner-Cavet JH Lakey NJ Robinson 《Canadian Metallurgical Quarterly》1998,273(33):21246-21252
The DNA primase gene, dnaG, has been isolated from the cyanobacterium Synechococcus PCC 7942. It is not part of a macromolecular synthesis operon but is co-transcribed with pheT and located adjacent to the metallothionein divergon, smt. At the carboxyl terminus of this DnaG is a Cys2/His2 zinc-finger motif. The carboxyl-terminal 91 residues bound 65Zn and 0.95 g atom of Zn2+ mol-1 were detected with 4-(2-pyridylazo)resorcinol. Following exposure to Cd2+, 0.95 g atom of Cd2+ was displaced by 2 equivalents of p-(hydroxymercuri) phenylsulfonate mol-1, while only 0.03 g atom of Cd2+ was displaced mol-1 polypeptide missing the carboxyl-terminal (residue 592 onward) zinc-finger motif. Zn2+ caused an increase in intensity, and a reduction in wavelength, of Trp fluorescence at the tip of the predicted zinc-finger, while EDTA caused the converse. Cells containing a single chromosomal codon substitution (C597S), altering the zinc-finger, were generated by exploiting Zn2+-sensitive smt mutants and the proximity of dnaG to smt. Cells in which smt and dnaG(C597S) had integrated into the chromosome were selected via restored Zn2+ tolerance. Synechococcus PCC 7942 and its dnaG(C597S) mutant grew at equivalent rates, but the latter had a reduced number of chromosomes. 相似文献
96.
This article describes novel attributes of the mushroom bodies of cockroaches revealed by recording from neurons in freely moving insects. The results suggest several hitherto unrecognized functions of the mushroom bodies: extrinsic neurons that discriminate between imposed and self-generated sensory stimulation, extrinsic neurons that monitor motor actions, and a third class of extrinsic neurons that predict episodes of locomotion and modulate their activity depending on the turning direction. Electrophysiological units have been correlated with neurons that were partially stained by uptake of copper ions and silver intensification. Neurons so revealed correspond to Golgi-impregnated or Lucifer yellow-filled neurons and demonstrate that their processes generally ascend to other areas of the protocerebrum. The present results support the idea of multiple roles for the mushroom bodies. These include sensory discrimination, the integration of sensory perception with motor actions, and, as described in the companion article, a role in place memory. 相似文献
97.
98.
T. Roszhart P. Sherman D. Williams A. Brand P. Joress B. Wing Kearfott Guidance Navigation Corporation Wayne NJ M. Berarducci 《战术导弹技术》2003,(4):56-61
基尔福特(Kearfott)制导与导航公司已经开发出用于战术惯性制导与导航应用的一种微机械振梁多敏感器(MVBM).这种MVBM是一种固态石英(硅Si)器件,它测量运动共轴的线加速度和角速率.这是通过单个柔性放置的检测质量来实现的,其中检测质量起到一种耦合模式的哥里奥利(Coriolis-哥氏)敏感器和加速度计的作用.位置敏感器是固定的,以使这两种测量在双级输出中有所不同,这样增加了标度因数,且相对于单极器件而言降低了共模而引起的热、振动以及老化误差. 相似文献
99.
1 Watt Er/Yb singlemode superfluorescent optical fibre source 总被引:2,自引:0,他引:2
A singlemode superfluorescent Er/Yb optical fibre source is described, capable of generating >1 W of output power. The spectral bandwidth of the source can be varied between 0.5 and 4 nm by filtering 相似文献
100.
NJ Malville 《Canadian Metallurgical Quarterly》1997,102(3):351-367
Predictions of P. R. Killeen's (1994) mathematical principles of reinforcement were tested for responding on ratio reinforcement schedules. The type of response key, the number of sessions per condition, and first vs. second half of a session had negligible effects on responding. Longer reinforcer durations and larger grain types engendered more responding, affecting primarily the parameter alpha (specific activation). Key pecking was faster than treadle pressing, affecting primarily the parameter delta (response time). Longer intertrial intervals led to higher overall response rates and shorter postreinforcement pauses and higher running rates, and ruled out some competing explanations. The treadle data required a distinction between the energetic requirements and rate-limiting properties of extended responses. The theory was extended to predict pause durations and run rates on ratio schedules. 相似文献