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With regard to cadmium toxicity, Drosophila strains v;bw and Austin represent extremes in resistance and sensitivity, respectively. Both strains produced metallothionein (MT) in response to Cd ions in their diet. Austin produced more metallothionein than v;bw at Cd ion levels below 0.2 mM, when both strains were allowed lifetime development on Cd2+-containing media. When the rate of MT appearance was measured for 4 days in young adults the results showed no clear trend with time within a strain or between strains. The plot of LC50 vs. MT levels for identical developmental conditions revealed that for v;bw small increases in MT corresponded to large increases in resistance whereas for the sensitive Austin even large increases in MT had comparatively little effect on increasing LC50. Results given here suggest that differences in total MT content do not explain the genetically demonstrable difference in Cd2+-resistance between v;bw and Austin. However, since two MT genes are identified in Drosophila, differences in resistance could be reflective of greater relative amounts of one "more important" MT in the resistant fly.  相似文献   
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The effectiveness of lysosubtilin and lysozyme, a combination thereof and a combination of these enzyme preparations (each alone and in combination) with vitamins as possible coimmunostimulants, which reduced the milk somatic cell count (SCC), were compared in a field trial. Seventy second to third lactation Lithuanian Black and White cows with a similar milk SCC ([750±200]×103?cells?ml?1) and of a similar weight (550±50?kg) were involved in the trial and were randomly allocated into seven groups (n=10). Lysosubtilin and/or lysozyme at doses of 0.02?g?kg?wt?1 and 0.2?g?kg?wt?1, respectively, and vitamins A, C and E (if any) at doses twice as high as required for nutritional adequacy were given, except for control group cows, once daily with feed for ten successive days. After four-, seven-, and ten-day periods of giving enzymes (with or without vitamins) a significant reduction of SCC (p<0.001) was observed in the milk of cows that received a combination of lysozyme with vitamins. On the tenth day a significant reduction of SCC (p<0.001) was also observed in the milk of cows that received lysozyme and lysosubtilin (each alone; without vitamins) or lysosubtilin in combination with vitamins. At the end of the trial (on the 15th day) SCC in milk of cows of all of the study groups was significantly lower (p<0.001) when compared with that of the control group.  相似文献   
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Neurosurgical Review - Treatment of osteoporosis with medications like teriparatide, a parathyroid hormone, is known to improve bone density and reduce the risk of osteoporotic vertebral fractures....  相似文献   
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Purpose: The aim of the study was to investigate whether maternal serum TSP-1 level was associated with PE.

Materials and methods: In our case control study, 84 pregnant women in the third trimester were included. Forty-one of them were healthy and 43 of them were with the diagnosis of PE. The diagnosis was based on the definitions of the National High Blood Pressure Education Program working Group on High Blood Pressure in Pregnancy. Preeclamptic patients were divided into two subgroups as mild and severe. Blood pressure (BP) of pregnant women were obtained in left-side lying position using a mercury sphygmomanometer after at least 10 minutes of rest. Ten milliliters of venous blood was taken from every pregnant women and dispensed into lithium heparin and serum was obtained. Samples were stored at ?80?°C until analyzed. Serum TSP-1 level was measured using enzyme-linked immunosorbent assay (ELISA). All tests were two-tailed and p < .05 was considered to be statistically significant.

Results: TSP-1 level was significantly lower in PE group than in controls (p?=?.003). Platelet counts were similar in two groups (p = .26). TSP-1 levels were significantly lower in severe PE than in mild PE cases. According to the subgroup analysis, TSP-1 level was found significantly lower in severe preeclampsia group compared to control group (p = .015).

Conclusions: In light of the association between endothelial dysfunction and preeclampsia, we claim that lower levels of TSP-1 which is released mostly from endothelial cells seem to reflect disease severity in PE. Our study reveals that maternal serum TSP-1 levels decrease in pregnant women presenting with PE and TSP-1 may be a new biomarker for the detection of PE and even severity of it. Further studies especially prospective ones with greater numbers of cases are needed.  相似文献   
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