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201.
Within 3 hours, 10 healthy male volunteers were infused 500 ml of a 5 percent emulsion in which 25 percent of the fat proportion had been replaced by MCT-fats. As expected, the ketone body concentration in the blood rose, while pyruvate remained constant and lactate dropped. The results show that, basically, a MCT-containing fat infusion is suited for parenteral nutrition and, because of their specific properties, medium chain triglycerides may be used as rapid energy donators. 相似文献
202.
Lower olefins, especially ethylene and propylene, have been found to add to alpha-sulfofatty acids in the presence of boron
trifluoride or its etherate to give dialkyl alpha-sulfofatty esters. Some of the reaction variables studied include catalyst,
catalyst concentration, and solvent. The esters were obtained as colorless, low melting solids after purification by low temperature
crystallization. 相似文献
203.
AS Gallus J Hirsh SE O'Brien JA McBride RJ Tuttle M Gent 《Canadian Metallurgical Quarterly》1976,235(18):1980-1982
The effect of low-dose heparin prophylaxis on venous thrombosis and bleeding after major elective surgery was studied in a prospective controlled study of 820 patients. The total incidence of venous thrombosis detected with leg-scanning using fibrinogen labeled with radioactive iodine (125I) was reduced from 16.0% in the control group to 4.2% in treated patients. More important, the incidence of popliteal or femoral vein thrombosis was reduced from 2.9% to 1.0%. Prophylaxis resulted in a slight increase in bleeding-minor wound hematoma, mean volume of blood transfused, and a post-operative hematocrit fall in treated patients. However, increased bleeding was clinically minor, and prophylaxis was well tolerated. 相似文献
204.
JT McBride ME Wohl DJ Strieder AC Jackson JR Morton RG Zwerdling NT Griscom S Treves AJ Williams S Schuster 《Canadian Metallurgical Quarterly》1980,66(5):962-970
To characterize the outcome of lobectomy in infancy and the low expiratory flows which persist after lobectomy for congenital lobar emphysema, 15 subjects with this history were studied at age 8-30 yr. Total lung capacity was normal in all, but higher values (P < 0.05) were observed in nine subjects with upper lobectomy than in five subjects with right middle lobectomy. Ratio of residual volume to total lung capacity was correlated (P < 0.05) with the amount of lung missing as estimated from normal relative weights of the respective lobes. Xe(133) radiospirometry in eight subjects showed that the operated and unoperated sides had nearly equal volumes at total lung capacity, but that the operated side was larger than the unoperated side at residual volume. Perfusion was equally distributed between the two sides. Similar findings were detected radiographically in four other subjects. Forced expiratory volume in 1 s and maximal midexpiratory flow rate averaged 72 and 45% of predicted, respectively. Low values of specific airway conductance and normal density dependence of maximal flows in 12 subjects suggested that obstruction was not limited to peripheral airways. Pathologic observations at the time of surgery and morphometry of the resected lobes were not correlated with any test of pulmonary function. These data show that lung volume can be completely recovered after lobectomy for congenital lobar emphysema in infancy. The volume increase occurs on the operated side, and probably represents tissue growth rather than simple distension. The response to resection is influenced by the particular lobe resected and may be associated with decreased lung recoil near residual volume. Low expiratory flows in these subjects could be explained by several mechanisms, among which a disproportion between airway and parenchymal growth in infancy (dysanaptic growth) is most compatible with our data. 相似文献
205.
Titanium-doped chromium oxide has been successfully employed in the form of thick film gas sensing devices where the porosity and surface conditioning are key aspects in providing a measurable gas response. Under normal gaseous atmospheres, where the partial oxygen pressure (p(O2)) is approximately 0.2 atm, sintering of the host material (-Cr2O3) to high densities is not possible, instead, significant grain growth occurs through evaporation-condensation transport mechanisms owing to the volatility of non-sesquioxide phases formed at high temperatures. The doping of -Cr2O3 with Ti does not significantly affect the sintering behaviour of the host oxide under atmospheric conditions, but instead tends to form a nanodimensional, surface-segregated ternary phase of a nominal composition: Cr2Ti2O7, whilst the composition of grain interiors is close to pure -Cr2O3. By reducing the p(O2) to 10–15 atm during sintering, thereby reducing the formation of volatile phases, solid state diffusion mechanisms have been encouraged allowing the densification of green bodies to a density >99% of the theoretical value. Ceramic bodies obtained by sintering in reduced p(O2) atmospheres display a single phase solid solution, isostructural with -Cr2O3 (space group R3c). 相似文献
206.
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208.
Tindall C.S. Palaio N.P. Ludewigt B.A. Holland S.E. Larson D.E. Curtis D.W. McBride S.E. Moreau T. Lin R.P. Angelopoulos V. 《IEEE transactions on nuclear science》2008,55(2):797-801
Silicon detectors with very thin entrance contacts have been fabricated for use in the IMPACT SupraThermal Electron (STE) instrument on the STEREO mission and for the Solid State Telescopes on the THEMIS mission. The silicon diode detectors were fabricated using a 200 Aring thick phosphorous doped polysilicon layer that formed the thin entrance window. A 200 Aring thick aluminum layer was deposited on top of the polysilicon in order to reduce their response to stray light. Energy loss in the entrance contact was about 350 eV for electrons and about 2.3 keV for protons. The highest detector yield was obtained using a process in which the thick polysilicon gettering layer was removed by chemical etching rather than chemical mechanical polishing. 相似文献
209.
Bend measurement using Bragg gratings in multicore fibre 总被引:3,自引:0,他引:3
Gander M.J. MacPherson W.N. McBride R. Jones J.D.C. Zhang L. Bennion I. Blanchard P.M. Burnett J.G. Greenaway A.H. 《Electronics letters》2000,36(2):120-121
The first measurements of curvature made using Bragg gratings written in separate cores of a multicore optical fibre are described. The gratings act as independent, but isothermal, strain gauges. The difference in Bragg wavelength between the gratings provides a temperature-independent measurement of the local curvature 相似文献
210.
Nick Benton Chung-Kil Hur Andrew J. Kennedy Conor McBride 《Journal of Automated Reasoning》2012,49(2):141-159
There are two approaches to formalizing the syntax of typed object languages in a proof assistant or programming language. The extrinsic approach is to first define a type that encodes untyped object expressions and then make a separate definition of typing judgements over the untyped terms. The intrinsic approach is to make a single definition that captures well-typed object expressions, so ill-typed expressions cannot even be expressed. Intrinsic encodings are attractive and naturally enforce the requirement that metalanguage operations on object expressions, such as substitution, respect object types. The price is that the metalanguage types of intrinsic encodings and operations involve non-trivial dependency, adding significant complexity. This paper describes intrinsic-style formalizations of both simply-typed and polymorphic languages, and basic syntactic operations thereon, in the Coq proof assistant. The Coq types encoding object-level variables (de Bruijn indices) and terms are indexed by both type and typing environment. One key construction is the boot-strapping of definitions and lemmas about the action of substitutions in terms of similar ones for a simpler notion of renamings. In the simply-typed case, this yields definitions that are free of any use of type equality coercions. In the polymorphic case, some substitution operations do still require type coercions, which we at least partially tame by uniform use of heterogeneous equality. 相似文献