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51.
Fluroide concentrations in teeth from the canton of Vaud were about at the same level reported from regions with 1,0 ppm F in the drinking water and from children receiving fluoride tablets during tooth formation age.  相似文献   
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In intact rabbits and in rabbits with intracerebral unilateral section of the n. oculomotorius, instillation of 2 drops of 0.1% adrenaline into the conjunctival sack increased and then decreased the intraocular pressure (IOP); i.v. administration of adrenaline (50 mcg) or electrophoresis decreased IOP. In conditions of disturbed parasympathetic innervation of the eye its sensitivity to adrenaline increased as revealed by a sharper lowering of IOP.  相似文献   
54.
Prolonged administration of cortisone to sexually immature rabbits and rats, in which m. tibialis anterior was injured preliminarily, inhibited the process of regeneration of the skeletal muscle tissue; this was expressed in the retarded growth of myosymplasts and of the muscle tubes. By the 15th postoperative day experimental rabbits (in comparison with control) showed a lesser area of muscle component of the regenerated tissue. Analysis of the intensity of methionine-H3 incorporation into the regenerating elements of the muscle tissue demonstrated a significant reduction of the label incorporation into the nuclear and cytoplasmic proteins of the myosymplasts of rats to which cortisone was given. Inhibition of the protein synthesis at the early stage of differentiation of the muscle tissue was expressed to a lesser extent than in the mature differentiated muscle fibers of the intact muscle.  相似文献   
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Blood flow: a mediator of ovarian function   总被引:1,自引:0,他引:1  
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1. Some features of the osmoregulatory mechanism are compared in four populations of Paranephrops zeal andicus White collected form freshwaters of different ionic concentrations. 2. Crayfish from freshwaters of ca, 2-0 mM-NaCl concentration show a sustained decrease in blood concentration of ca. 8% when placed in 0-2 mM-NaCl. 3. Populations from freshwaters of ca. 0-2-0-4 mM-NaCl show lower rates of net salt loss in distilled water and higher rates of net salt uptake form dilute NaCl solutions than do populations from freshwaters of ca. 0-8-2-0 mM-NaCl. 4. Renal salt losses over the first 24 h in distilled water account for ca. 18% of the total salt loss. 5. It is suggested that P. zealandicus from environments of lowest concentration shows a similar degree of adaptation to freshwater as do crayfish of the northern hemisphere. It differs in possessing a substantially higher blood concentration.  相似文献   
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Nisin is a bacteriocin that is globally employed as a biopreservative in food systems to control gram-positive, and some gram-negative, bacteria. Here we tested the bioactivity of nisin A-producing Lactococcus lactis NZ9700 and producers of bioengineered variants thereof against representatives of the gram-negative genus Thermus, which has been associated with the pink discoloration defect in cheese. Starting with a total of 73 nisin variant-producing Lactococcus lactis, bioactivity against Thermus was assessed via agar diffusion assays, and 22 variants were found to have bioactivity greater than or equal to that of the nisin A-producing control. To determine to what extent this enhanced bioactivity was attributable to an increase in specific activity, minimum inhibitory concentrations were determined using the corresponding purified form of these 22 nisin A derivatives. From these experiments, nisin M17Q and M21F were identified as peptides with enhanced antimicrobial activity against the majority of Thermus target strains tested. In addition, several other peptide variants were found to exhibit enhanced specific activity against a subset of strains.  相似文献   
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