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31.
Ultrastructure of the chloroplasts of white rubber rabbitbrush ( Chrysothamnus nauseosus (Pallas) Britt. ssp. albicaulis ) was observed with electron microscopy. In addition, leaf anatomy was observed with light microscopy. Previously, it had been reported that the leaves of this desert shrub exhibited a relatively high rate of photosynthesis when compared to other C 3 plants. Comparisons with chloroplasts of other C 3 and C 4 plants demonstrated a reduced amount of granal stacking in the rabbitbrush. However, the classification of rabbitbrush as a C 3 plant is confirmed. RUBP-carboxylase concentration is reported at about 450 mg · ml -1 stromal space based on the estimation of 1 mg of chlorophyll per 25 ul of stromal space in a normal C 3 chloroplast and data from an assay to determine the ratio of RUBP-carboxylase to chlorophyll. 相似文献
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A survey of parasites from 39 stool specimens taken from 36 Indochinese refugees who are now living in Utah County, Utah, indicated representative intestinal helminths (worms), and protozoans upon clinical examination. .Approximately 75% of the stools contained nematodes, and 55.5% had protozoans. Parasites found were Entamoeba coli, Chilomastix mesnili, Endolimax nana, Giardia lamblia, lodamoeba buetschlii, Clonorchis sinensis, Trichuris trichiura, Ascaris lumbricoides, and Plasinodium vivax. The most common protozoan observed was Entamoeba coli (1979 and 1980) while the most common helminths were Ascaris lumbricoides ) (1979) and Clonorchis sinensis (1980). These data were comparable to studies of refugees at two other laboratories in Utah and one at Washington, D.C. 相似文献
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Coleman D 《Population trends》1999,(98):42-52
Population Trends had provided an overview of European and world demographic issues since its inception in 1975. This article covers the abundant sources of demographic data on all European countries with information on their availability in printed and electronic formats. 相似文献
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Estimate of the volatile nitrosamine content of UK food 总被引:2,自引:0,他引:2
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Donald T. Campbell outlines an epistemological theory that attempts to be faithful to evolution through natural selection. He takes his position to be consistent with that of Karl R. Popper, whom he credits as the primary advocate of his day for natural selection epistemology. Campbell writes that neither he nor Popper want to give up the goal of objectivity or objective truth, in spite of their evolutionary epistemology. In discussing the conflict between an epistemology based on natural selection and objective truth, Campbell cites an article by the German sociologist and philosopher Georg Simmel entitled ‘On a Connection of Selection Theory to Epistemology’, as presenting the issue in a notably forthright manner.The present essay summarizes Simmel's article, with the purpose of clarifying, in terms that Campbell apparently finds satisfactory, the conflict that Campbell acknowledges between an evolutionary epistemology and ultimate truth; the essay then examines the responses of Campbell and Popper to Simmel's position. While Campbell and Popper acknowledge the work of Simmel, their responses suggest something less than a full consideration of Simmel's position. 相似文献
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Cookson WO Ubhi B Lawrence R Abecasis GR Walley AJ Cox HE Coleman R Leaves NI Trembath RC Moffatt MF Harper JI 《Nature genetics》2001,27(4):372-373
We have carried out a genome screen for atopic dermatitis (AD) and have identified linkage to AD on chromosomes 1q21, 17q25 and 20p. These regions correspond closely with known psoriasis loci, as does a previously identified AD locus on chromosome 3q21. The results indicate that AD is influenced by genes with general effects on dermal inflammation and immunity. 相似文献
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