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71.
72.
73.
Kader Köse Pakize Doĝan Yildiz Kardas Recep Saraymen 《Biological trace element research》1996,53(1-3):51-56
The plasma selenium (Se) levels were determined in patients with rheumatoid arthritis (RA) and healthy controls. Plasma Se
levels in 60 patients were found to be significantly lower than those in 60 normal, healthy controls (p<0.001). Similar significant differences were determined in sex-matched comparisons between patients and controls (p<0.001) but there was no significant difference in plasma Se levels in sex-matched comparisons in both groups (p>0.05).
Our results suggest that Se is an important factor in RA. 相似文献
74.
Cornucoryphe n. gen. from the Middle Cambrian of the Cantabrian Mountains and Aragón is a unicornianConocoryphe with pronounced alae. 相似文献
75.
M. Popović S. KevreŠan J. Kandrač J. Nikolić N. Petrović R. Kastori 《Biologia Plantarum》1996,38(2):281-287
In young sugar beet plants cadmium suppressed the activity of nitrate reductase, glutamine synthetase and glutamate dehydrogenase,
whereas sulphur exhibited a protective role towards activity of these enzymes, except of glutamine synthetase. Protein synthesis
was suppressed in the absence of S in nutrient medium; the lowest level was at 10-3 M Cd2+. Chloroplast pigment contents were increased by S while Cd2+, even in the lowest concentration, (10−5 M) showed a repressive effect. The highest concentrations of Cd2+ (10−3 M) caused a decrease in dry mass, whereas S induced its increase. Nitrate content was increased in the presence of
Cd2+ and decreased by increased concentration of S.
Acknowledgement: The authors acknowledge financial support of the Ministry for Science and Technology of Serbia.
The paper was presented at 9th Congress of the Federation of European Societies of Plant Physiology, Brno, Czech Republic,
3–8 July 1994. 相似文献
76.
The effect of the growth form of the inducing microorganism on specificTrichoderma harzianum mycolytic enzyme production was studied. The pelleted form ofRhizopus nigricans gave a better product concerning protoplast formation ability. The maximum yield of protoplasts from the target fungusCochliobolus lunatus was 1×108 ml–1. Analysis of individual specific enzyme activities inTrichoderma mycolytic enzyme preparations confirms the importance of high chitinase and low protease activity for high protoplast yields. Supplementation of the production medium with chitin increased the chitinase activity in theTrichoderma exoenzyme mixture. 相似文献
77.
Hemoglobin concentrations ofChironomus cf.plumosus larvae were measured in two different habitats of the same pond. Larger larvae have higher hemoglobin concentrations than small larvae. There is strong indication that the animals of poorly oxygenated deep water, have higher hemoglobin concentrations than the animals from the well-oxygenated littoral zone. 相似文献
78.
Christoph Meier Walter Senn Rudolf Hauser Manfred Zimmermanne 《Journal of mathematical biology》1994,32(6):563-572
The classical Nicholson-Bailey model for a two species host-parasitoid system with discrete generations assumes random distributions of both hosts and parasitoids, randomly searching parasitoids, and random encounters between the individuals of the two species. Although unstable, this model induced many investigations into more complex host-parasitoid systems. Local linearized stability analysis shows that equilibria of host parasitoid systems within the framework of a generalized Nicholson-Bailey model are generally unstable. Stability is only possible if host fertility does not exceede
4=54.5982 and if superparasitism is unsuccessful. This special situation has already been discovered by Hassell et al. (1983) in their study of the effects of variable sex ratios on host parasitoid dynamics. We discuss global behaviour of the Hassell-Waage-May model using KAM-theory and illustrate its sensitivity to small perturbations, which can give rise to radically different patterns of the population dynamics of interacting hosts and parasitoids. 相似文献
79.
Cells ofBacillus megaterium contain 35–45% of poly(3-hydroxybutyrate) (PHB) at the beginning of the stationary phase. This amount is only slightly affected
by the medium composition. The PHB granules are spherical with the mean diameter of 1.15 μm. 相似文献
80.
Vanadium was determined by radiochemical neutron activation analysis (RNAA) with proven accuracy in urine of workers occupationally
exposed to vanadium-rich dust in a vanadium pentoxide production plant, and values in the range of 3.02–762 ng/mL (median
33.0 ng/mL) were found. In a control group consisting of administrative workers of the plant, urinary vanadium levels were
found in the range of 1.05–53.4 ng/mL (median 2.53 ng/mL), whereas in an another control group of occupationally nonexposed
persons, these values amounted to 0.066–0.489 ng/mL (median 0.212 ng/mL).
Accuracy of the results was tested by analysis of reference material IAEA A-13 Animal Blood and NIST SRM-1515 Apple Leaves,
and very good agreement was found with literature and the NIST certified values, respectively. Unlike urine, no significant
differences were found for cystine levels in fingernails and hair of exposed and control persons. 相似文献