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481.
Jacobus P. Van Wouwe Marcel Veldhuizen Jeroen J. M. De Goeij Cornelis J. A. Van den Hamer 《Biological trace element research》1990,25(1):57-69
Exchangeable erythrocytic zinc is measured by 65Zn uptake in and release from erythrocytes under standardized and near, physiological conditions: 7.6 microM zinc and 580 microM albumin in the medium. The intracellular exchangeable erythrocytic zinc pool in healthy volunteers amounts to 5 mumol zinc/L packed cells. The half-time of the exchange is 7 h, its activation energy 84 kJ/mol. The effects of the variation in temperature and the concentrations of albumin, as well as the effects of some zinc carriers, cell transport inhibitors, and stress hormones on the 65Zn uptake are measured. 相似文献
482.
We have investigated the genetic population structure within and the genetic differentiation between local populations of the large blue butterfly Maculinea alcon throughout the Jutland peninsula. Samples were collected as eggs on foodplants (Gentiana pneumonanthe), and reared to 4th instar caterpillars in the laboratory. A significant excess of homozygotes was found for all the investigated allozyme loci in most of the populations. A North-South cline was observed for the allele frequencies at some of the loci and for several linkage groups. Because some of the allele frequency clines were parallel to clines in adult morphological variation, we interpret our results as evidence for the co-existence of at least two gene pools within the Danish Maculinea alcon populations. Multilocus electrophoretic data revealed highly positive but variable FST values, which under this scenario would reflect varying frequencies of the Maculinea gene pools across the local populations. The significantly positive FIS values indicate that these gene pools are at least partly reproductively isolated (Wahlund effect). The co-occurrence of several Maculinea alcon gene pools on many local sites in Jutland is of great importance for conservation of the fragmented Maculinea populations. Our results show that there is probably more Maculinea biodiversity to conserve than was previously thought, and suggests that extant populations are more fragmented and vulnerable than counts of flying adults or eggs on foodplants indicate. 相似文献
483.
Donovan B. Burger Jacobus C. Crause Arthur M. Spickett Albert W. H. Neitz 《Experimental & applied acarology》1991,13(1):59-63
The identification of antigens unique to the positive strain of the tickHyalomma truncatum is discussed. Cattle were separately immunized against sweating-sickness-positive and sweating-sickness-negative ticks. A study was done to demonstrate the difference in protein patterns of crude salivary-gland extracts between positive and negative ticks. Immunological differences were identified using Western blots. A 32 kDa band was found to be unique to the positive strain. 相似文献