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51.
Summary Absolute circulating number and functions of blood monocytes (i.e., pinocytosis, phagocytosis, and chemotaxis) were studied in 25 patients with untreated bronchogenic carcinoma and in 28 control subjects. The absolute circulating monocyte count was increased in 20 (80%) of the patients. There was no difference in the pinocytic and phagocytic activity of patient and control monocytes. In contrast, patient monocytes showed depressed chemotactic responsiveness. This defect was more severe in small cell anaplastic carcinoma than in the other histologic types of bronchogenic carcinoma (P=0.001), and may explain the difference in macrophage infiltration seen in solid tumours of the lung. There was no correlation between chemotaxis and clinical stage. Depressed chemotaxis may be related to a plasma factor, since patient plasma inhibited the chemotaxis of control monocytes as well as the activity of chemotactic agents. The defective chemotaxis and the presence of plasma inhibitory activity may interfere with the ability of blood monocytes to accumulate as macrophages in tumour sites. Abbreviations used in this paper are: MCR, monocyte chemotactic response; SAC, small cell anaplastic bronchogenic carcinoma; OBC, non-small cell bronchogenic carcinoma MEM, Eagle's minimal essential medium; CFI, chemotactic factor inhibitor(s); HSA, human serum albumin  相似文献   
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Henrik Balslev 《Brittonia》1979,31(2):243-247
Rostkovia magellanica has hitherto been considered a species of Patagonia and the subantarctic islands from New Zealand to South Georgia. An old report from Ecuador has been considered erroneous, but it has now been rediscovered there. Brief notes on the ecology of the species are given, and the possible origin of its distribution is discussed. Long-distance dispersal by birds is suggested as having caused the disjunct distribution on mainland South America.  相似文献   
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Ecosystems - Patterns of animal migration and the ecological forces that shape them have been studied for centuries. Yet ecological impacts caused by the migration, such as altered...  相似文献   
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Fungi play many essential roles in ecosystems. They facilitate plant access to nutrients and water, serve as decay agents that cycle carbon and nutrients through the soil, water and atmosphere, and are major regulators of macro‐organismal populations. Although technological advances are improving the detection and identification of fungi, there still exist key gaps in our ecological knowledge of this kingdom, especially related to function . Trait‐based approaches have been instrumental in strengthening our understanding of plant functional ecology and, as such, provide excellent models for deepening our understanding of fungal functional ecology in ways that complement insights gained from traditional and ‐omics‐based techniques. In this review, we synthesize current knowledge of fungal functional ecology, taxonomy and systematics and introduce a novel database of fungal functional traits (FunFun). FunFun is built to interface with other databases to explore and predict how fungal functional diversity varies by taxonomy, guild, and other evolutionary or ecological grouping variables. To highlight how a quantitative trait‐based approach can provide new insights, we describe multiple targeted examples and end by suggesting next steps in the rapidly growing field of fungal functional ecology.  相似文献   
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The house sparrow is an important model species for studying physiological, ecological and evolutionary processes in wild populations. Here, we present a medium density, genome wide linkage map for house sparrow (Passer domesticus) that has aided the assembly of the house sparrow reference genome, and that will provide an important resource for ongoing mapping of genes controlling important traits in the ecology and evolution of this species. Using a custom house sparrow 10 K iSelect Illumina SNP chip we have assigned 6,498 SNPs to 29 autosomal linkage groups, based on a mean of 430 informative meioses per SNP. The map was constructed by combining the information from linkage with that of the physical position of SNPs within scaffold sequences in an iterative process. Averaged between the sexes; the linkage map had a total length of 2,004 cM, with a longer map for females (2,240 cM) than males (1,801 cM). Additionally, recombination rates also varied along the chromosomes. Comparison of the linkage map to the reference genomes of zebra finch, collared flycatcher and chicken, showed a chromosome fusion of the two avian chromosomes 8 and 4A in house sparrow. Lastly, information from the linkage map was utilized to conduct analysis of linkage disequilibrium (LD) in eight populations with different effective population sizes (Ne) in order to quantify the background level LD. Together, these results aid the design of future association studies, facilitate the development of new genomic tools and support the body of research that describes the evolution of the avian genome.  相似文献   
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Reviews in Fish Biology and Fisheries - A systematic review and meta-analysis was conducted to evaluate the appropriate tag:fish size ratio when tagging juvenile salmonids (genera Oncorhynchus,...  相似文献   
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