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21.
22.
The semicontinuous separation/concentration of two solutes with different molecular size by the size exclusion cyclic separation
method is based on the opposite swelling responses of two gels to a temperature change. Experimental results of separation
and concentration of solutes are verified qualitatively by the theoretical models based on the local equilibrium assumption.
Separation of two solutes is shown by the breakthrough curves in coupled gel columns. In closed coupled columns, the volumetric
space for the large molecules which are totally excluded from the gels becomes smaller, creating a concentrating effect as
the gels swell when temperature changes. A mechanistic model is suggested to predict the large molecule concentration to increase
to its solubility limit as cycle repeats. 相似文献
23.
The measurement of neonatal responses to painful stimuli remains a significant clinical problem. Although numerous measures have been evaluated, instruments that are valid, reliable, and clinically feasible are not yet available. The purpose of this paper is to critique the studies that have been done using biochemical, physiological, and behavioral measures to evaluate neonatal responses to painful stimuli. Specific issues regarding measurement in premature and critically ill neonates are emphasized. The intent of this review and critique of the literature is to stimulate additional research into the assessment of neonatal pain. 相似文献
24.
DL Schacter A Uecker E Reiman LS Yun D Bandy K Chen LA Cooper T Curran 《Canadian Metallurgical Quarterly》1997,8(18):3993-3998
To determine whether physical match between studied and tested items influences blood flow increases in the hippocampal formation associated with recognition memory, positron emission tomography (PET) was used to measure changes in regional cerebral blood flow while healthy volunteers made old/new judgements about line drawings of objects. Some objects were tested in the same size and orientation as they had appeared earlier during the study phase of the experiment; other objects were tested in a different size or orientation than when they were studied. Blood flow increases in the vicinity of the hippocampal formation were observed in the same object condition compared with the size change and the orientation change conditions, even though recognition accuracy was affected significantly only by orientation change. Results add to previous findings suggesting that physical similarity between studied items and test cues may contribute to hippocampal activation during episodic retrieval. 相似文献
25.
Koo K.P. Bucholtz F. Dagenais D.M. Dandridge A. 《Photonics Technology Letters, IEEE》1989,1(12):464-466
A compact fiber-optic magnetometer constructed using a short piece of amorphous metal wire (5-cm long×100-μm diameter) as the magnetostrictive transducer is discussed. The inherently large ratio of length to cross-sectional area results in a low demagnetization along the axial direction. A magnetostrictive constant of 5×10-5 /Oe2, which is 10-50 times larger than the reported values for transducers made from Metglas ribbons, was measured. Minimum detectable magnetic fields on the order of 10-5 Oe/Hz1/2 at 1 Hz were achieved using a 5-cm-long sensing fiber 相似文献
26.
Intramuscular phenol neurolysis is a well-known procedure used to decrease spasticity and improve function in patients who have failed to respond to more conservative forms of intervention. Traditionally, this approach has been limited to spasticity reduction in limb muscles, and its use in managing spasticity of the facial muscles has not been described in the literature. This case report describes a new and previously unreported application of intramuscular neurolysis for managing severe unrelenting facial muscle spasticity in a postanoxic encephalopathic patient. Prior to the procedure, hypertonicity in the orbicularis oris muscle was so profound that it limited speech and affected cosmetic, hygienic, and nutritional status. After intramuscular phenol neurolysis of the orbicularis oris muscle, the patient's level of functioning improved. 相似文献
27.
A yeast mitochondrial translation initiation codon mutation affecting the gene for cytochrome oxidase subunit III (COX3) was partially suppressed by a spontaneous nuclear mutation. The suppressor mutation also caused cold-sensitive fermentative growth on glucose medium. Suppression and cold sensitivity resulted from inactivation of the gene product of RPS18A, one of two unlinked genes that code the essential cytoplasmic small subunit ribosomal protein termed S18 in yeast. The two S18 genes differ only by 21 silent substitutions in their exons; both are interrupted by a single intron after the 15th codon. Yeast S18 is homologous to the human S11 (70% identical) and the Escherichia coli S17 (35% identical) ribosomal proteins. This highly conserved family of ribosomal proteins has been implicated in maintenance of translational accuracy and is essential for assembly of the small ribosomal subunit. Characterization of the original rps18a-1 missense mutant and rps18a delta and rps18b delta null mutants revealed that levels of suppression, cold sensitivity and paromomycin sensitivity all varied directly with a limitation of small ribosomal subunits. The rps18a-1 mutant was most affected, followed by rps18a delta then rps18b delta. Mitochondrial mutations that decreased COX3 expression without altering the initiation codon were not suppressed. This allele specificity implicates mitochondrial translation in the mechanism of suppression. We could not detect an epitope-tagged variant of S18 in mitochondria. Thus, it appears that suppression of the mitochondrial translation initiation defect is caused indirectly by reduced levels of cytoplasmic small ribosomal subunits, leading to changes in either cytoplasmic translational accuracy or the relative levels of cytoplasmic translation products. 相似文献
28.
As many as 3033 patients with myocardial infarction residing in rural areas were kept under observation. In this population, myocardial reinfarction (MRI) was diagnosed in 411 subjects, with 78.8% having had it for 4 years. Those MRI patients ranging between 51 to 60 years showed the greatest prevalence (44.3%). The ratio of micro- to macrofocal (through-and-through) MRI was 1:3, that of males to females 9:1. Microfocal MRI was commonly associated with a pain-free variant of the disease (23.5%) with low frequency of thromboembolic complications (3.1%). Every fifth patient with macrofocal (through-and-through) renecrosis presented with aneurysm of the heart. In a 10-year and longer follow-up, mortality from MRI was 43.6 percent among patients with macrofocal MRI, while deaths attributable to microfocal MRI were estimated to be 28.9 percent. High mortality rates suggest great severity of illness and low efficacy of the drug therapy adopted. 相似文献
29.
30.
The fabrication of functional textiles able to provide thermal regulation and comfort for the body has attracted increasing interest in recent years. This research investigated fabric coatings containing energy absorbing, temperature stabilizing, phase‐change material microcapsules (PCMMcs), and their methods of application. Specifically, a coated fabric was directly prepared by a dual‐type coating method, in which the PCMMcs were dispersed in a polyurethane coating solution with no binder. The thermal performances of the dual‐coated samples were evaluated by differential scanning calorimetry, and their physical characteristics were examined by scanning electron microscopy, thermal vision camera, porosity, water vapor transmission rate (WVTR), and water entry pressure (WEP) analyses. Furthermore, the microclimate characteristics of the thermally enhanced fabrics were investigated under experimental conditions using a human‐clothing‐environment (HCE) simulator system. The study results confirmed the superior performance of the dual‐coated fabrics in terms of thermal regulation and body comfort, compared with those coated by the dry or wet coating method, because of the improved WEP, WVTR, and thermal performance. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献