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1.
Summary

Allium cepa root-tip cells were first exposed to low ‘conditioning’ doses of ionizing radiation: to X-rays (0·06 or 0·26 Gy) or to incorporated tritium (1·8 × 104 or 7·2 × 104 Bq/ml; specific activity: 740·0 GBq/mmol) and subsequently given a ‘challenge’ dose of 1·5 Gy of X-rays. A reduction in X-ray-induced chromosomal damage was brought about by prior exposure to 0·26 Gy of X-rays, while cells receiving the lower conditioning dose (0·06 Gy of X-rays) did not show any significant reduction. In cells grown in the presence of [3H]TdR on the other hand, the adaptive response was evident after both doses given. The results are essentially in agreement with those published by Wolff's group for human lymphocytes in showing that plant cells in vivo can become ‘adapted’ by exposure to low-level irradiation so that they become more resistant to the clastogenic effects of X-rays delivered subsequently.  相似文献   
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Although cystatin C (Cys) and albuminuria (Alb) are predictors of end‐stage renal disease in the general population, there are limited data about the performance of these markers alone or combined with respect to the prediction of the kidney transplant outcome. We assessed the ability of one‐yr creatinine (Cr), MDRD equation, Cys, Hoek equation, Alb, the logarithm of albuminuria (LogAlb), and two products of these variables for predicting death‐censored graft loss (DCGL) in 127 kidney transplant recipients. Mean follow‐up time was 5.6 ± 1.7 yr. During this time, 18 patients developed DCGL. The area under the receiver operating characteristic curve for DCGL ranged from 71.1% to 85.4%, with Cys*LogAlb being the best predictor. Cys‐based variables and variables combining LogAlb and renal function estimates have better discrimination ability than Cr‐based variables alone. After multivariate analysis, quartiles of all one‐yr variables (except of Cr and MDRD) were independent predictors for DCGL. Predictors combining Alb and a Cr‐ or Cys‐based estimate of renal function performed better than those markers alone to predict DCGL. Cys‐based predictors performed better than Cr‐based predictors. Using a double‐marker in kidney transplantation, it is possible to identify the highest risk group in which to prioritize specialty care.  相似文献   
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A novel biscoumarin, 6,6′,7,7′-tetramethoxyl-8,8′-biscoumarin (1), was isolated from the ethyl acetate extract of Urtica dentata Hand, together with five known compounds named as 7,7′-dihydroxy-6,6′-dimethoxy-8,8′-biscoumarin (2), 7,7′-dimethoxy-6,6′-biscoumarin (3), scoparone (4), vanillic acid (5), and daucosterol (6). Structures of the isolated compounds were elucidated on the basis of spectroscopic analysis including 2D NMR experiments. Compounds 1 and 2 were confirmed to be a rare carbon–carbon linked symmetrical biscoumarin. Compounds 1–4, especially 1 (IC50 = 8.18 × 10? 5 mol/l), showed potent immunosuppressive activities as determined by the Cell Counting Kit-8 assay for lymphocyte proliferation. Also, in the FACS analysis, 1 (IC50 = 5.19 × 10? 4 mol/l) promoted the differentiation of CD4+CD25+Foxp3+ T regulatory cells distinctly compared to the normal control. Thus, 1 possessed specific immunosuppressive property by eliciting T regulatory cells, which may provide a potential treatment strategy for autoimmune diseases.  相似文献   
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To prepare verticinone derivatives with significant antitussive, expectorant, and antiasthmatic activities, the compounds 3β-acetylverticinone (1), 3-ketoverticinone (2), 3β-benzoylverticinone (3), 3β-propionylverticinone (4), 3β-butyrylverticinone (5), and 3β-butoxycarbonylverticinone (6) have been prepared. All of these are new compounds. Among them, 16 exhibited potent antitussive and expectorant activities; 1 and 36 displayed various antiasthmatic activities. The antitussive activity of 16, the expectorant activity of 12 and 46, and the antiasthmatic activity of 1 are higher than those of verticinone. The results demonstrated that 1 had dominant biological activities, suggesting that it would be a potential antitussive, expectorant, and antiasthmatic agent.  相似文献   
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Phytochemical investigation of Juglans cathayensis Dode root barks led to the isolation of two novel nitrogen-containing naphthoquinones named juglonbutine (1) and binaphthine (2). Their structures were elucidated by the extensive analysis of the spectroscopic data. In addition, six known naphthoquinones (38) were also isolated from the same material for the first time.  相似文献   
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This clinical study evaluated a new surface treatment of ion implantation with CO ions which has previously been subjected to extensive study in animal models. The aim of this work was to assess its effect in humans. Experimental mini-implants were used; half of their longitudinal surface was machined and the other half was treated with CO ion implantation. The study was conducted in healthy volunteer patients who required prosthetic treatment with dental implants, and in accordance with the corresponding ethics committees. Coinciding with the insertion of commercial implants for oral restoration, one or two mini-implants were placed in the upper maxillary tuberosity or in the retromolar trigone of the mandible. The mini-implants were removed with a trephine jointly with a small volume of surrounding bone after a 3-month period. Two evaluation methods were used and both showed a greater degree of bone integration in the mini-implant section that underwent CO ion implantation treatment in comparison with the non-treated surface: 62.9% vs. 57.9%, and 54.8% vs. 46.2%. In addition, no adverse reactions were observed in the surface treatment with CO ion implantation. These results confirm the positive benefits in humans, based on the findings obtained from previous animal experiments.  相似文献   
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