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951.
Summary A technique for measuring root activity of agricultural crops in totality in situ under field conditions has been developed for the first time. The method essentially consists of measuring the activity emanating from roots after plant injection of a gamma radiating isotope using a probe. This also helps continuous monitoring of root growth changes over time.  相似文献   
952.
Summary Utilizing specific rabbit antiserum againstM. arthritidis together with complement, a portion of the marrow 7-day CFUs population of CBA mice infected with live mycoplasma organisms 1 day previously was shown to be inactivated. These cells might therefore be considered as candidate target cells forM. arthritidis. 11-day CFUs were unaffected by similar treatment.  相似文献   
953.
G Uhlenbruck  J Beuth  V Weidtman 《Experientia》1983,39(11):1314-1315
Development of liver metastases in 1542 cancer patients was investigated. It was found that in certain liver diseases the incidence of liver metastases was reduced compared to that in cancer patients with otherwise normal livers. We propose that this reduction may be due to a reduced function of the liver-specific lectins.  相似文献   
954.
955.
956.
Lipid peroxidation and activities of antioxidative enzymes were studied in the brain cortex after short (15 min) cerebral ischemia and reperfusion (10 min) in rats. Conjugated dienes (CD) and thiobarbituric acid-reactive substances (TBARS) were significantly elevated in the group of rats with ischemia followed by reperfusion in comparison to the ischemic animals. Superoxide dismutase (SOD) activity significantly increased in the group of animals with ischemia and reperfusion. No significant changes in the activities of glutathione peroxidase (GP) were observed. Stobadine administered before ischemia or before reperfusion decreased the level of TBARS. Stobadine probably prevents malondialdehyde (MDA) formation from hydroperoxide or might elevate the activity of aldehyde dehydrogenase. In contradiction to the findings after long-lasting (4 h) ischemia and subsequent reperfusion, no decrease in the concentration of CD or in the activity of SOD or GP was found.  相似文献   
957.
Endangered species and the law.   总被引:10,自引:0,他引:10  
V Geist 《Nature》1992,357(6376):274-276
Taxonomy does not deserve its reputation as an arcane science. As the following examples from ungulate taxonomy show, classification has important implications for conservation legislation.  相似文献   
958.
Summary The present results, using isolated rat aortic strips and portal vein segments, demonstrate that ethanol (170–430 mM) significantly inhibits calcium uptake in these 2 different types of vascular smooth muscle.Supported by NIH grant No. HL-18015 and NIMH grant No. MH-26236. Request for reprints should be addressed to B.M. Altura.  相似文献   
959.
V Lance  D W Owens  I P Callard 《Experientia》1979,35(8):1119-1120
Plasma progesterone, testosterone, total estrogens and immunoreactive gonadotropin were measured in nesting and non-nesting sea turtles, Chelonia mydas. Progesterone and gonadotropin concentrations were significantly higher in nesting than in non-nesting turtles, testosterone was not significantly different in either group and total estrogens appeared to be slightly in the nesting group.  相似文献   
960.
The methyl 2-chloro-3 (4-chlorophenyl) propionate is quickly hydrolysed through coleoptiles of wheat (coleoptile test). Then, depending on the concentration of the compounds, one observes mainly a further degradation (at 0,01 mM) of the acid or conjugation (at 0,1 mM) of it with cystein in vivo. This second type of physiological neutralisation appears to be more efficient than the catabolism which give derivatives of benzoic acid.  相似文献   
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