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1.
Plant and Soil - Agricultural practices often have persistent effects on soil physicochemical properties and soil biota, which can feedback to influence plant performance. We investigated... 相似文献
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J B Bristol P M Emmett K W Heaton R C Williamson 《BMJ (Clinical research ed.)》1985,291(6507):1467-1470
The habitual diet of 50 patients with large bowel cancer, as assessed by a dietary history method, was compared with that of 50 closely matched controls. Patients were included only if their symptoms were unlikely to have changed previous eating habits. The mean daily intakes of all major nutrient classes and of dietary fibre were estimated. Patients with large bowel cancer consumed 16% more energy than controls (mean (SEM) daily intake 9.92 (0.41) v 8.56 (0.32) MJ (2370 (98) v 2046 (76) kcal), respectively; p less than 0.0001), mainly in the form of carbohydrate (21% more; 282.6 (13.7) v 233.4 (10.5) g; p less than 0.0001) and fat (14% more; 100.8 (4.3) v 88.4 (3.2) g; p less than 0.001). The extra carbohydrate was largely in the form of sugars depleted in fibre and the extra fat as combinations of fat and such sugars. As the selection criteria used make it unlikely that this eating pattern was caused by the disease the data suggest that a high intake of sugars depleted in fibre and fat predisposes to the development of large bowel cancer. 相似文献
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Enzymes of Intermediary Carbohydrate Metabolism in the Obligate Autotrophs Thiobacillus thioparus and Thiobacillus neapolitanus 总被引:2,自引:1,他引:1 下载免费PDF全文
Levels of enzymes operative in the Embden-Meyerhof-Parnas (glycolytic) pathway, pentose phosphate cycle, citric acid cycle, and certain other phases of intermediary carbohydrate metabolism have been compared in Thiobacillus thioparus and T. neapolitanus. All enzymes of the glycolytic pathway except phosphofructokinase were demonstrated in both organisms. There were some striking quantitative differences between the two organisms with respect to the activities of the individual enzymes of the glycolytic pathway and the citric acid cycle. Qualitative differences were also found: the isocitrate dehydrogenase activity of T. thioparus is strictly nicotinamide adenine dinucleotide phosphate (NADP)-dependent, whereas that of T. neapolitanus is primarily nicotinamide adenine dinucleotide-dependent, activity with NADP being low; the glucose-6-phosphate dehydrogenase of T. thioparus is particulate, whereas that of T. neapolitanus is partly soluble and partly particulate; the 6-phosphogluconate dehydrogenase of T. thioparus is soluble, that of T. neapolitanus is partly soluble and partly particulate. All enzymes which function in the carbon reduction cycle were present at very high levels. In contrast, enzymes which operate exclusively in cycles other than the carbon reduction cycle were present at low levels. Of the enzymes not operative in the carbon reduction cycle that were examined, isocitric dehydrogenase had the highest specific activity. Both organisms possessed reduced nicotinamide adenine dinucleotide dehydrogenase activity. The qualitative and quantitative aspects of the data are discussed in relation to possible biochemical explanations of obligate autotrophy. 相似文献
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Characterization of two mutant metJ proteins with reduced, temperature-dependent capacity to regulate Escherichia coli K-12 met regulon elements. 总被引:1,自引:1,他引:0 下载免费PDF全文
At 28 degrees C, but not at 34 or 42 degrees C, strains with the metJ193 allele repressed chromosomal met genes but not a plasmid-borne met promoter. Increasing the metJ193 gene dosage to two copies resulted in overrepression of chromosomal and plasmid-borne met promoters at 28 degrees C. Suppressing the metJ185 amber mutation with supF (tRNATyr) produced the MetJ185F protein. Strains producing MetJ185F repressed chromosomal met promoters but not a plasmid-borne met promoter at 42 degrees C. These are the first known defective MetJ proteins with documented temperature-dependent function. 相似文献
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Hans J. De Boeck Juliette M. G. Bloor Rien Aerts Michael Bahn Claus Beier Bridget A. Emmett Marc Estiarte Jos M. Grünzweig Aud H. Halbritter Petr Holub Anke Jentsch Karel Klem Juergen Kreyling Gyrgy Krel‐Dulay Klaus Steenberg Larsen Alexandru Milcu Jacques Roy Bjarni D. Sigurdsson Melinda D. Smith Marcelo Sternberg Vigdis Vandvik Thomas Wohlgemuth Ivan Nijs Alan K. Knapp 《Global Change Biology》2020,26(2):e6-e7
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Danilo ML Prado Fabiana B Benatti Ana L de Sá-Pinto Ana P Hayashi Bruno Gualano Rosa MR Pereira Adriana ME Sallum Eloisa Bonfá Clovis A Silva Hamilton Roschel 《Arthritis research & therapy》2013,15(2):R46
Introduction
Exercise training has emerged as a promising therapeutic strategy to counteract physical dysfunction in adult systemic lupus erythematosus. However, no longitudinal studies have evaluated the effects of an exercise training program in childhood-onset systemic lupus erythematosus (C-SLE) patients. The objective was to evaluate the safety and the efficacy of a supervised aerobic training program in improving the cardiorespiratory capacity in C-SLE patients.Methods
Nineteen physically inactive C-SLE patients were randomly assigned into two groups: trained (TR, n = 10, supervised moderate-intensity aerobic exercise program) and non-trained (NT, n = 9). Gender-, body mass index (BMI)- and age-matched healthy children were recruited as controls (C, n = 10) for baseline (PRE) measurements only. C-SLE patients were assessed at PRE and after 12 weeks of training (POST). Main measurements included exercise tolerance and cardiorespiratory measurements in response to a maximal exercise (that is, peak VO2, chronotropic reserve (CR), and the heart rate recovery (ΔHRR) (that is, the difference between HR at peak exercise and at both the first (ΔHRR1) and second (ΔHRR2) minutes of recovery after exercise).Results
The C-SLE NT patients did not present changes in any of the cardiorespiratory parameters at POST (P > 0.05). In contrast, the exercise training program was effective in promoting significant increases in time-to-exhaustion (P = 0.01; ES = 1.07), peak speed (P = 0.01; ES = 1.08), peak VO2 (P = 0.04; ES = 0.86), CR (P = 0.06; ES = 0.83), and in ΔHRR1 and ΔHRR2 (P = 0.003; ES = 1.29 and P = 0.0008; ES = 1.36, respectively) in the C-SLE TR when compared with the NT group. Moreover, cardiorespiratory parameters were comparable between C-SLE TR patients and C subjects after the exercise training intervention, as evidenced by the ANOVA analysis (P > 0.05, TR vs. C). SLEDAI-2K scores remained stable throughout the study.Conclusion
A 3-month aerobic exercise training was safe and capable of ameliorating the cardiorespiratory capacity and the autonomic function in C-SLE patients.Trial registration
NCT01515163. 相似文献10.
Emilie M. M. Santos Wiro J. Niessen Albert J. Yoo Olvert A. Berkhemer Ludo F. Beenen Charles B. Majoie Henk. A. Marquering MR CLEAN investigators 《PloS one》2016,11(1)