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931.
Bacteriochlorophyll a reaction-center complex I from Chlorobium limicola f. thiosulfatophilum 6230 (Tassajara) was incubated in 2 M guanidine - HCl and then chromatographed on cross-linked dextran or agarose gel. Two principal components were separated: a larger component with photochemical activity (bacteriochlorophyll a reaction-center complex II) and a smaller component without activity (bacteriochlorophyll a protein). Complex II contains carotenoid, bacteriochlorophyll a, reaction center(s), and cytochromes b and c, but lacks the well characterized bacteriochlorophyll a protein contained in Complex I. Complex II carries out a light-induced reduction of cytochrome b along with an oxidation of cytochrome c. 相似文献
932.
933.
JR Mendell LM Silverman HL Verrill JM Parker WH Olson 《Canadian Metallurgical Quarterly》1976,26(10):968-974
The life expectancy of males in the United States is lower than that of males in most of the developed countries and in some of the not-so-developed ones. U.S. females, by contrast, do much better in international ranking. This study compares the mortality of U.S. white males with that of Swedish males who have had the highest reported male life expectancies in the world since the early 1960s. Life expectancy at birth in 1969-71 was 67.9 for U.S. white males compared with 71.9 for Swedish males. Greater U.S. white male mortality is found at all ages from birth through ages 75-79. At the upper ages there is a reversal of the differential with U.S. white males having lower mortality than their Swedish counterparts. The greatest relative differentials between the two male populations is found at ages under 1, ages 20-24, and ages 50-59. At ages under 1 the greater U.S. white male mortality is accounted for mainly by higher death rates from infectious diseases, at ages 20-24 by higher rates from the external causes of death (specifically accidents and homicide), and at ages 50-59 from most of the major organic causes of death. 相似文献
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935.
The work was undertaken to study late results of surgical treatment of suppurative lung diseases during 1950-1974. Questionaries were sent to 420 operated patients. Answers were received from 328 (78%) patients, 86% of them were examined clinically, 14%--were estimated according to questionaries and their physician findings. 50 per cent of patients were followed up for 10-24 years. A positive effect was gained in 94.8%. 82 per cent of the operated patients have practically recovered well. The causes of poor issues are described, and trends for their improvement are delineated. 相似文献
936.
New results for the recirculating flow inside a square cavity obtained by a finite element method are presented. The full Navier-Stokes equations in the form of a single, fourth order equation for stremfunction is recast into arestricted variational principles, which form finite element discretization. A triangular element with Hermitian interpolation is used, such that the velocities are continuous and the incompressibility is satisfied exactly. The resulting nonlinear system is solved by Newton-Raphson iteration. Calculations are carried out with several gridworks of progressive show: (1) the convergence of solutions with refinement for fixed Reynolds number ; and (2) the loss of accuracy with for fixed gridwork. The range of covered is from to 3450. The features illustrated include the enlargement of the inviscid core of rigid rotation, the intensification of primary and secondary vortices and the appearance of a third secondary vortex near the upper upstream corner at . 相似文献
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