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771.
772.
A food recording electronic device to simplify the collection of dietary data is described. The need for a subject to maintain a quantitative account of food intake, and for a dietitian to subsequently code this record prior to computer analysis, are both eliminated using this approach. In combination with an electronic kitchen balance, the recorder, which is based upon a single-board computer (SBC) and special keyboard, enables the weight, food type and time of consumption of each food to be recorded automatically in response to simple key entry. The resident program, transparent to the user, allows data from surveys lasting up to three weeks to be stored for subsequent serial downloading to a host computer. 相似文献
773.
774.
RI Damper 《Canadian Metallurgical Quarterly》1976,15(6):488-500
Subjects were presented with an initially stationary binaural image formed by the fusion of two identical pulses, without interaural time difference (ITD), at the two ears. The image was then made to traverse the subject's auditory perceptual space by introducing ITD, varying linearly with time, under computer control. The direction of movement, i.e. towards the right or left ear, could be reversed by the listener, by pressing a button. Subjects were requested to keep the image central, by pressing the button when they judged that deviation from subjective centre had occurred. Experiments of this type can be considered as analogous to Békésy audiometry, where the subject automatically traces his threshold of hearing, in that here the listener traces out his auditory perceptual centre as it varies with time. Hence, equivalent analyses to those employed for Békésy audiometry are possible. Subsequent to the initial part of the experiment, an additional pulse was added to one channel, preceding the original pulse, to form a pulse pair. The monaural masking of the original pulse by this additional pulse thus acts to shift the pre-existing binaural image. The effect of varying the amplitude and onset time of the masking pulse, relative to the original pulse, on the Békésy-type trace was examined. 相似文献
775.
Beck Niels C.; Horwitz Ellen; Seidenberg Michael; Parker Jerry; Frank Robert 《Canadian Metallurgical Quarterly》1985,53(3):402
Examined the factor structure of the WAIS—R in a sample of 200 general medical (GM) patients and 271 psychiatric patients. The mean age of the Ss was 38.9 yrs. Results of 2- and 3-factor principal factor solutions with varimax rotations were compared to the factor structure of the WAIS—R normative sample (n?=?1,880) and a sample of vocational counseling patients (n?=?84), as well as an additional sample of psychiatric patients (n?=?114). Across all of these samples, coefficients of congruence for the 1st 2 factors (Verbal, Performance) were .97 or greater, and coefficients of congruence for the 3rd factor (Freedom From Distractability) ranged from .93 to .97. Results indicate that the WAIS—R has a robust factor structure and provides empirical evidence for the existence of Verbal, Performance, and Freedom From Distractability factors on the WAIS—R in psychiatric and medical populations. (13 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
776.
Large (approximately 10 g) soil and sediment samples are often required for analysis of low-level man-made actinides for monitoring environmental radioactivity. However, use of large environmental samples often results in significant chemical losses during chemical separations due to matrix interferences. We present a technique based on the ion-exchange resin Diphonix which selectively collects actinides and lanthanides into a common form, which then behaves uniformly and predictably during subsequent separation schemes. Diphonix is attractive for this purpose because it has an extremely high affinity for actinides and a low affinity for most common ions and is resistant to hydrofluoric acid. After being adsorbed onto Diphonix resin in a column mode at a pH approximately 1, actinides are completely eluted with 0.5 M 1-hydroxyethylidene-diphosphonic acid (HEDPA). After destruction of the HEDPA by ozonation or use of Fenton's reagent, Am, Pu, U, and Th are separated from each other and the remaining matrix by use of extraction chromatographic resins. We obtained high and consistent chemical recoveries (mean, 85%), as well as excellent chemical separations, for Am, Pu, U, and Th through the entire procedure for several 10-g soil and sediment samples. 相似文献
777.
pH‐Responsive Isoniazid‐Loaded Nanoparticles Markedly Improve Tuberculosis Treatment in Mice 下载免费PDF全文
Angela A. Hwang Bai‐Yu Lee Daniel L. Clemens Barbara Jane Dillon Jeffrey I. Zink Marcus A. Horwitz 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(38):5066-5078
Tuberculosis is a major global health problem for which improved therapeutics are needed to shorten the course of treatment and combat emergence of drug resistance. Mycobacterium tuberculosis, the etiologic agent of tuberculosis, is an intracellular pathogen of mononuclear phagocytes. As such, it is an ideal pathogen for nanotherapeutics because macrophages avidly ingest nanoparticles even without specific targeting molecules. Hence, a nanoparticle drug delivery system has the potential to target and deliver high concentrations of drug directly into M. tuberculosis‐infected cells—greatly enhancing efficacy while avoiding off‐target toxicities. Stimulus‐responsive mesoporous silica nanoparticles of two different sizes, 100 and 50 nm, are developed as carriers for the major anti‐tuberculosis drug isoniazid in a prodrug configuration. The drug is captured by the aldehyde‐functionalized nanoparticle via hydrazone bond formation and coated with poly(ethylene imine)–poly(ethylene glycol) (PEI–PEG). The drug is released from the nanoparticles in response to acidic pH at levels that naturally occur within acidified endolysosomes. It is demonstrated that isoniazid‐loaded PEI–PEG‐coated nanoparticles are avidly ingested by M. tuberculosis‐infected human macrophages and kill the intracellular bacteria in a dose‐dependent manner. It is further demonstrated in a mouse model of pulmonary tuberculosis that the nanoparticles are well tolerated and much more efficacious than an equivalent amount of free drug. 相似文献
778.
Cover Picture: A Unified Sensor Architecture for Isothermal Detection of Double‐Stranded DNA,Oligonucleotides, and Small Molecules (ChemBioChem 5/2015) 下载免费PDF全文
779.
Y Li J Kang J Friedman L Tarassishin J Ye A Kovalenko D Wallach MS Horwitz 《Canadian Metallurgical Quarterly》1999,96(3):1042-1047
780.
BH Horwitz P Zelazowski Y Shen KM Wolcott ML Scott D Baltimore CM Snapper 《Canadian Metallurgical Quarterly》1999,162(4):1941-1946
B cells lacking individual NF-kappa B/Rel family members exhibit defects in activation programs. We generated small resting B cells lacking p65 or p50 alone, or lacking both p50 and p65, then evaluated the ability of these cells to proliferate, secrete Ig, and undergo Ig class switching. B cells lacking p65 proliferated well in response to all stimuli tested. However, these cells demonstrated an isolated defect in switching to IgG3, which was associated with a decrease in gamma 3 germline CH gene expression. Whereas, previously reported, B cells lacking p50 alone had a severe proliferative defect in response to LPS, a moderate defect in response to CD40 ligand (CD40L), and normal proliferation to Ag receptor cross-linking using dextran-conjugated anti-IgD Abs (alpha delta-dex), B cells lacking both p50 and p65 exhibited severely impaired proliferation in response to LPS, alpha delta-dex, and CD40L. This defect could be overcome by simultaneous administration of alpha delta-dex and CD40L. In response to this latter combination of stimuli, B cells lacking both p50 and p65 secreted Ig and underwent isotype switching to IgG1 as efficiently as B cells lacking p50 alone. These data demonstrate a role for the p65 subunit of NF-kappa B in germline CH gene expression as well as functional redundancy between p50 and p65 during proliferative responses. 相似文献