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21.
RJ O''Hara J Greenman PJ Drew AW McDonald GS Duthie PW Lee JR Monson 《Canadian Metallurgical Quarterly》1998,41(4):460-463
OBJECTIVE: Spontaneous spinal epidural hematoma (SSEH) is an idiopathic accumulation of blood in the vertebral epidural space without identifiable predisposing factors. First reported in 1869, the clinical outcome in children younger than 18 years old has not been clearly delineated. DESIGN: A comprehensive review of the English language literature revealed 26 patients younger than 18 years old with reported clinical outcomes. The 27th case is presented. RESULTS: Complete neurologic recovery occurred in 14 of 27 (52%) patients, partial recovery in 12 of 27 (44%) patients, and death in 1 of 27 (4%) patients. CONCLUSION: There is an overall good prognosis for neurologic recovery in children who experience SSEH. 相似文献
22.
CM McDonald 《Canadian Metallurgical Quarterly》1998,9(1):9-48
This article has reviewed the clinical approach to the diagnostic evaluation of progressive neuromuscular diseases with an emphasis on relevant neuromuscular history, family history, clinical examination findings, laboratory studies, and a brief discussion of the role of muscle biopsy. Molecular genetic and immunocytochemistry studies of muscle have been major advances in the diagnostic evaluation of the neuromuscular disease patient; however, all diagnostic information must be interpreted within the context of relevant clinical information. In some instances, a precise diagnosis is not medically possible; however, the accurate characterization of an individual patient within the most appropriate NMD clinical syndrome often allows the clinician to provide the patient and family with accurate prognostic information and anticipatory guidance for the future. After synthesizing all available clinical and diagnostic information, the physiatrist or neurologist may at times determine that an NMD patient has an inappropriate diagnosis warranting further diagnostic evaluation. This issue focuses on the rehabilitation of progressive neuromuscular diseases with an emphasis on optimization of health, prevention or minimization of complications, and enhancement of quality of life. Appropriate rehabilitation approaches require an accurate diagnosis. In addition, patient quality of life in NMD depends on access to current and accurate information. The first step in providing accurate information and appropriate treatment is constantly ensuring that NMD patients have appropriate diagnoses based on a through evaluation of clinical information and appropriate application of current medical science and available diagnostic technology. 相似文献
23.
T Putilina C Jaworski S Gentleman B McDonald M Kadiri P Wong 《Canadian Metallurgical Quarterly》1998,252(2):433-439
A unique clone, isolated from a human pancreatic cDNA library, was sequenced and characterized. Northern blot analysis showed that the gene is active in a number of fetal and adult tissues, and immunoblots showed expression in nuclear and cytosolic cell fractions. The gene corresponding to the clone was localized to chromosome 13 by human/rodent somatic cell hybrid panels. The largest open reading frame contains a LIM domain, and the deduced peptide from the open reading frame appears to have the characteristics of a LIM-only protein, designated LMO7. RT-PCR and genomic sequence analyses indicate that expression of this gene product is subject to tissue-specific modulation by elimination of the LIM domain by alternative splicing in neural tissues. 相似文献
24.
X Chen DJ Kempf HL Sham BE Green A Molla M Korneyeva S Vasavanonda NE Wideburg A Saldivar KC Marsh E McDonald DW Norbeck 《Canadian Metallurgical Quarterly》1998,8(24):3531-3536
The 2-isopropyl thiazolyl group is a highly optimized P3 ligand for C2 symmetry-based HIV protease inhibitors, as exemplified in the drug ritonavir. Here we report that incorporation of this P3 ligand into a piperazine hydroxyethylamine series also yielded novel, highly potent inhibitors. In tissue culture assays, the presence of human serum was less deleterious to the activity of these inhibitors than to that of ritonavir. Furthermore, potent activity against ritonavir resistant HIV was observed. 相似文献
25.
Peanut skin, when treated with formaldehyde to polymerize tannins, is a highly efficient substrate for removal of many heavy metal ions from aqueous waste solutions. The ions Ag1+, Cd2+, Cr6+, Cu2+, Hg2+, Ni2+, Pb2+, Zn2+, as well as Ca2+ and Mg2+, were contacted with formaldehyde-treated peanut skin. Quantitative removal could be achieved with Ag1+, Cd2+, Cu2+, Hg2+, Pb2+, and Zn2+. Capacity of the substrate for ions was promising for Pb2+ (2.1 meq/g substrate), Cu2+ (3.0 meq/g), and Cd2+ (1.3 meq/g). Sorption from a solution containing Cd2+, Cu2+, Hg2+, Ni2+, Pb2+, Zn2+, on a packed column of formaldehyde-treated peanut skin indicated that Hg2+, Pb2+, and Cu2+ were rapidly and completely bound to the packing, while Cd2+, Ni2+, and Zn2+ were poorly bound until the preferred ions had been removed from solution. 相似文献
26.
M. M. Mossoba M. P. Yurawecz J. A. G. Roach H. S. Lin R. E. McDonald B. D. Flickinger E. G. Perkins 《Lipids》1994,29(12):893-896
This study reports the structural elucidation of diunsaturated 5- or 6-membered ring cyclic fatty acid monomers (CFAM) isolated
from heated flaxseed oil by complementary gas chromatography (GC)-mass spectrometry (MS) and GC-matrix isolation-Fourier transform
infrared spectroscopy (MI-FTIR). Infrared measurements of CFAM were carried out on methyl ester derivatives as well-resolved
chromatograms were obtained on a polar 100% cyanopropyl polysiloxane capillary GC column. By contrast, electron ionization
MS of methyl ester derivatives was of limited value because of double bond migration during the ionization process in the
mass spectrometer. This communication reports definitive MS fragmentation patterns that can confirm ring position and double
bond position along the fatty acid chain in 1,2-disubstituted CFAM determined as 2-alkenyl-4,4-dimethyloxazoline derivatives.
Double bond configuration (cis, trans, or conjugatedcis,cis) in CFAM was confirmed by GC-MI-FTIR. The presence of CFAM, degradation products found in used frying oils, is a potential
source of dietary toxicity.
This work was presented in part at the 84th American Oil Chemists' Society Annual Meeting held in Anaheim, CA, in April 1993. 相似文献
27.
Abstract. It is well known that the sum of moving average processes is itself a moving average process. Existing theory does not provide formulae relating the innovations in the sum process to those in the component processes when some zeros of the autocovari-ance function of the sum process are on the unit circle. This gap is filled here by first showing that these zeros are necessarily shared by the component processes. Conditions for the innovations in the sum process to be current are given. Throughout the paper contemporary innovations in the component processes are allowed to be correlated, replacing the usual assumption that they are uncorrelated. 相似文献
28.
D. L. Purcell B. T. McClure J. McDonald Hemendra N. Basu 《Journal of the American Oil Chemists' Society》1996,73(3):381-388
An evaluation of the exhaust emissions from a compression ignition engine for fuels composed of 100 and 30% methyl esters
of soy oil (SME) is described. These fuels were compared with a low-sulfur, petroleum #2 diesel fuel in a Caterpillar 3304,
prechamber, 75 kW diesel engine, operated over heavy- and light-duty transient test cycles developed by the United States
Bureau of Mines. More than 60 h of testing was performed on each fuel. The objective was to determine the influence of the
fuels upon diesel particulate matter (DPM) and gaseous emissions. The effect of a modern diesel oxidation catalyst (DOC) also
was determined in an effort to minimize emissions. Neat SME produced a higher volatile fraction of the DPM, but much less
carbon soot fraction, leading to overall DPM reductions of 23 to 30% for the light- and heavy-duty transients. The DOC further
reduced the volatile fraction and the total DPM. The SME fuel reduced gaseous emissions of CO by 23% and hydrocarbons by over
30% without increasing NOx. The DOC further reduced CO and hydrocarbon levels. Mutagenicity of the SME exhaust was low. Results indicate that SME fuel,
used with a proper DOC, may be a feasible emission reduction technology for underground mines.
References to specific products do not imply endorsement by the U.S. Bureau of Mines, a now defunct agency. 相似文献
29.
McDonald Shawn M.; Willson Richard C.; McCammon J.Andrew 《Protein engineering, design & selection : PEDS》1995,8(9):915-924
The titration behavior of the ionizable residues of the HyHEL-5henegg lysozyme complex and its individual components has beenstudied using continuum electrostatic calculations. Severalresidues of HyHEL-5 had pKa values shifted away from model valuesfor isolated residues by more than three pH units. Shifts awayfrom the model values were smaller for the residues of hen egglysozyme. A moderate variation in the pKa values of the titratablegroups was observed upon increase of the ionic strength from0 to 100 mM, amounting to 12 pH units in most cases.Under physiological conditions, the net charge of HyHEL-5 wasopposite that for hen egg lysozyme. Several residues, includingthose involved in the ArgGlu salt bridges that have beenproposed to be important in antibody-antigen binding, had pKavalues that were changed significantly upon binding. The maintitration event upon antibody-antigen binding appears to beloss of a proton from residue GluH50 of the Fv molecule. Thelimitations of our calculation methods and the role they mightplay in the design of antibodies for use in assays, sensorsand separations are discussed 相似文献
30.
Two-dimensional correlation relaxometry studies of cement pastes performed using a new one-sided NMR magnet 总被引:1,自引:0,他引:1
Peter J. McDonald Jonathan Mitchell Peter S. Aptaker Luc Monteilhet 《Cement and Concrete Research》2007,37(3):303-309
We present preliminary results of the first NMR T1-T2 two-dimensional relaxation correlation experiments performed using a one-sided NMR system in cement based materials. Two-dimensional correlation relaxometry has itself only recently been demonstrated in cement paste where it proved to be a particularly sensitive probe of pore-water dynamics providing direct information on exchange of water between the gel and capillary pore networks. Further to this we have observed differences in the structural development of a selection of cement pastes throughout the early stages of hydration and verified the theoretical frequency dependence of the ratio T1 / T2. When coupled with instrumentation developments in one-sided NMR magnets the way is opened to detailed, spatially resolved studies of the development of hydration and porosity in the surface layers (top 50 mm) of cementitious materials. A new magnet, suitable for such applications, is discussed. 相似文献