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71.
To assess the completeness of human immunodeficiency virus (HIV) reporting among hospital inpatients whose records listed diagnostic codes for HIV infection but who did not meet the 1987 AIDS case definition, we conducted a statewide hospital study of admissions between January 1, 1986 and December 31, 1990. Of the 396 HIV-infected hospital inpatients identified, 313 (79%) had been reported to the State HIV Registry. HIV reporting was less complete for patients who were older and/or were blood product recipients. Of the 313 reported patients, 189 (60%) had been reported prior to their first hospital admission. Temporal improvements were noted in the completeness of HIV reporting among the hospital patients (1986: 65%; 1987: 81%; 1988: 64%; 1989: 82%; 1990: 86%; Chi square for linear trend 9.6, p < 0.01) and prior to their first hospital admission (1986: 31%; 1987: 34%; 1988: 49%; 1989: 64%; 1990: 72%; Chi square for linear trend 26.6; p < 0.01). Women were more likely than men to be reported prior rather than during or after their first hospital admission (71% vs. 55%; p < 0.01). Of the 155 patients with CD4+ T-lymphocyte test results, 41 had CD4+ counts < 200 mm3 and met the 1993 but not the 1987 AIDS case definition. In South Carolina most (79%) diagnosed, hospitalized, HIV-infected patients had been reported to the State HIV REgistry, with improvements in reporting occurring over time. Findings suggest that the 1993 AIDS case definition will improve our ability to monitor severe morbidity related to HIV. 相似文献
72.
H Meyer 《Canadian Metallurgical Quarterly》1998,72(4):28-29
The veterinary surgeon G. C. HAUBNER (1806-1882) was teacher for veterinary science at the Royal prussian academia for agriculture in Eldena near Greifswald (1836-1852) and at the royal school of veterinary science in Dresden (1853-1879). He stimulated animal nutrition in different ways. First of all he disclosed the theoretical gaps in the field of animal nutrition during the first half of the 19th century, furthermore he transferred the knowledge in agriculture chemistry and animal physiology to feeding praxis and altogether he favoured the transition from the empirical to the scientific based animal nutrition, last not least by starting exactly planned and practiced feeding experiments (s. Table 2). Most remarkable are his very early work on digestion physiology in ruminants (1837), his proof (1854), that fiber is digestible in ruminants or horses as well as his investigations on nutrition related diseases in cattle (smelting-house-smoke- and deficiency-diseases). 相似文献
73.
We report the first experimental study of the NMR lineshape anisotropy in the orientationally ordered cubic phase of a D2 single crystal. The para-D2 concentration covered the range 0.72<X<0.82. The observed line shapes were obtained by means of Fourier transform techniques from the solid echoes recorded with a pulsed NMR spectrometer operating at 5.9 MHz. Theoretical line shapes and their second moments forp-D2 (with angular momentumJ=1 and spinI=1) and foro-D2 (withJ=0, I=2) were calculated as a function of the applied field direction from the theory by A. B. Harris. Good agreement was obtained for all directions, provided that, just as for solid H2, a Gaussian function for the distribution of molecular axial alignment was assumed with an rms spreading angle of 6 deg forX=0.77. No change in the anisotropy of the second moment in the disordered phase was detected between the initial (hcp) crystal and after repeated thermal cyclings through the martensitic transition. This result implies no change in the orientation of the plane for the sliding nets during repeated passages through the transition. Furthermore, we report measurements of the longitudinal relaxation time for bothp-D2 ando-H2 versusT over the temperature range 0.5<T<3.5 K. The complex behavior reported previously for both H2 and D2 was confirmed. Measurements of the relaxation times as a function of the applied field direction in the ordered phase at 1.2 K showed no anisotropy within experimental error, and this result is discussed in the light of predictions by Hardy and Berlinsky. Finally, the polarization of theJ=0 molecules is studied as a function of the concentrationX of theJ=1 molecules and their state of orientational order over a wide range ofX andT in the ordered and disordered states. The results are compared with predictions of A. B. Harris and with previous data on polycrystalline samples. 相似文献
74.
The effective thermal conductivity eff has been measured for 1.6 K for mixtures with 10–6–2. Both eff and the derived impurity mass diffusion coefficient Diso show an unexpected dependence on the height h of the fluid layer. A scaled representation of Diso leads to a purely phenomenological model involving an effective length scale, proportional to X–1 and temperature independent. The relations so obtained are consistent with the observations as well as with the observed transition curve QC(X) to non-linear behavior. 相似文献
75.
J L Willems P Arnaud J H van Bemmel P J Bourdillon R Degani B Denis F M Harms P W Macfarlane G Mazzocca J Meyer 《Computers and biomedical research》1985,18(5):439-457
As a result of an international cooperative project entitled "Common Standards for Quantitative Electrocardiography" (CSE), an ECG reference data base has been established with the aim of standardizing computer-derived ECG measurements. The objective of the project is to reduce the wide variation in wave measurements currently obtained by ECG analysis programs. A library of 250 ECGs with selective ECG abnormalities was established and a comprehensive reviewing scheme was devised for the visual determination of the onsets and offsets of P, QRS, and T. This task was performed by a board of cardiologists on highly amplified, selected complexes from the library. A subset was examined in order to study beat-to-beat and intraobserver variability. By using a modified Delphi approach, individual outlying point estimates were eliminated in four successive rounds. In this way final referee estimates were obtained which proved to be highly reproducible and precise. A reference library has thereby been developed which allows testing of the performance of ECG measurement programs and is a useful instrument in establishing recommendations for more precise measurement rules and definitions. 相似文献
76.
Charles C. Agosta Suwen Wang L. H. Cohen H. Meyer 《Journal of Low Temperature Physics》1987,67(3-4):237-289
Shear viscosity measurements with a precision of 0.05% are reported for3He and4He along near-critical isochores 0.85
c
<1.12, where
c
is the critical density. The temperature range was –10–4<<1, where =(T – T
c)/T
c is the reduced temperature. The experiments were carried out with a torsional oscillator operating at 158 Hz, driven at resonance in a phase-locked loop. The absolute value of the viscosity was obtained by calibration at the superfluid transition of4He, based on published values and from direct calculations using the free decay time constant of the oscillations. The data are analyzed in terms of a model using the recent mode-coupling (MC) expressions by Olchowy and Sengers, and where account is taken of the earth's gravity effects. The theory could be fitted very well to the experiment with a single free parameter, the cutoff wave numberq
D, which was found to be 3.0×106 and 7.0×106 cm–1 for3He and4He, respectively. We have used for the critical exponent the MC predicted value of z=0.054, which permits a fit superior to that using z=0.064 predicted by dynamic renormalization group (DRG) theories. Detailed comparisons are made between the model calculations and data for various isochores and isotherms and good agreement is obtained. The effects of gravity are described in some detail. The predicted frequency effect in viscosity measurements is calculated for3He and is shown to be obscured by gravity effects. Using the Olchowy-Sengers formulas, we have also fitted the MC theory to the critical thermal conductivity data of3He, again withq
D as the only free parameter. This fit gaveq
D=6 × 107 cm–1, which in the ideal situation should have been the same asq
D from viscosity. We also discuss a representation of the3He viscosity data along the critical isochore by a power law and first correction-to-scaling erm. Using the viscosity and the critical conductivity data for3He, we have calculated the dynamic amplitude ratio and obtained =1.05±0.10, in agreement with predictions from MC and DRG theories. Also, agrees with data of classical fluids. Finally, a comparison is made of recent shear viscosity data for CO2 by Bruschi and Torzo with those on He. The CO2 data are also analyzed in terms of the MC theory, and the discrepancies are discussed. In the Appendices, we present the results of new compressibility measurements on3He along the critical isochore, as used in the MC analysis. We also present a brief analysis of the fluid hydrodynamics in the torsional oscillator leading to relations for the viscosity as a function of the measured quantities. Finally, we give a short outline of the vertical density profile calculations from the earth's gravity field for the calculations of the viscosity nearT
c. 相似文献
77.
78.
Mette B. Let Charlotte Jacobsen Edwin N. Frankel Anne S. Meyer 《European Journal of Lipid Science and Technology》2003,105(9):518-528
The oxidative deterioration of milk emulsions supplemented with 1.5 wt‐% fish oil was investigated by sensory evaluation and by determining the peroxide value and volatile oxidation products after cold storage. Two types of milk emulsions were produced, one with a highly unsaturated tuna oil (38 wt‐% of n‐3 fatty acids) and one with cod liver oil (26 wt‐% of n‐3 fatty acids). The effect of added calcium disodium ethylenediaminetetraacetate (EDTA) on oxidation was also investigated. Emulsions based on cod liver oil with a slightly elevated peroxide value (1.5 meq/kg) oxidised significantly faster than the tuna oil emulsions, having a lower initial peroxide value (0.1 meq/kg). In the tuna oil emulsions the fishy off‐flavour could not be detected throughout the storage period. Addition of 5—50 ppm EDTA significantly reduced the development of volatile oxidation products in the cod liver oil emulsions, indicating that metal chelation with EDTA could inhibit the decomposition of lipid hydroperoxides in these emulsions. This study showed that an oxidatively stable milk emulsion containing highly polyunsaturated tuna fish oil could be prepared without significant fishy off‐flavour development upon storage, provided that the initial peroxide value was sufficiently low. 相似文献
79.
A commercial lithium aluminosilicate glass-ceramic material is investigated by high-resolution transmission electron microscopy after different heat treatments. Evidence is presented that epitaxy of β-quartz crystals on ZrTiO4 -type crystallites is the critical step initiating silicate crystallization. 相似文献
80.
Antioxidant activity of grape extracts in a lecithin liposome system 总被引:15,自引:0,他引:15
Ock-Sook Yi Anne S. Meyer Edwin N. Frankel 《Journal of the American Oil Chemists' Society》1997,74(10):1301-1307
Extracts of 14 different grapes were tested for their antioxidant activities in a copper-catalyzed lecithin liposome oxidation
assay and analyzed for their phenolic components by high-performance liquid chromatography (HPLC). The total phenolic contents
of the grape extracts varied from 176 to 1236 mg gallic acid equivalents (GAE)/L. Extracts of red wine grape varieties contained
higher concentrations of phenolics than other varieties. When compared at the same 20 μM GAE basis, the grape extracts inhibited
formation of conjugated diene hydroperoxides by 25.1 to 67.9%, and hexanal formation by 49.3 to 97.8%. Extracts of red table
grape varieties Red Globe and Emperor and white wine grape varieties Chardonnay and Sauvignon Blanc gave the highest antioxidant
activities. The relative percentage inhibition of conjugated dienes and hexanal correlated with total phenols (r=0.86 and 0.89). HPLC analyses showed that anthocyanins were the most abundant phenolic compounds in extracts of red grapes,
and flavonols were most abundant in extracts of white grapes. 相似文献