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Ohne ZusammenfassungMitteilung aus der Önochemischen Versuchsstation Geisenheim a. Rh.  相似文献   
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Ohne ZusammenfassungMitteilung aus der Önochemischen Versuchsstation Geisenheim a. Rh.  相似文献   
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Two cDNA clones (LEPAL-1 and LEPAL-2) encoding phenylalanine ammonia-lyase were isolated from cell suspension cultures of Lithospermum erythrorhizon. Northern kinetic studies showed that LEPAL-1 mRNA contents markedly increased one day after inoculation of the cells into fresh medium, then decreased to the steady-state level. The course of mRNA accumulation paralleled that of PAL enzyme activity. The rapid induction of PAL activity seems to reflect the induction of dihydroechinofuran biosynthesis, while shikonin was produced at the steady-state level of PAL activity. The course of LEPAL-2 mRNA accumulation seemed to be similar to, but much lower than that of LEPAL-1. In the intact plant, both genes are expressed mainly in the root, the organ in which shikonin is exclusively produced and accumulated. Genomic Southern blot analyses showed that both genes are present in the genome as single copies.  相似文献   
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EEG potentials evoked by cues and targets were recorded in Posner's visual cueing task from 10 patients with lesions of the right parietal cortex and from age-matched healthy subjects. The patients' N1 component evoked by left-side cues was reduced at the right-parietal recording site, suggesting a general impairment in processing left-side visual input. As usual, patients' keypress responses were delayed when left targets were preceded by right cues. There were two correlates of this delay in the patients' EEG potentials evoked by the critical combination of right cue/left target: their mean amplitude 160-280 ms after target onset ('Nd') was less negative than with other combinations of cue and target, and the following frontal P300 was enhanced. The Nd reduction seems to be an on-line measure of patients' momentary decrease of attention for the left hemifield, while the frontal P300 might reflect the patients' attempts at reorienting. In conclusion, different components were sensitive to different aspects of the patients' disorder, suggesting the utility of this approach for developing detailed hypotheses on the mechanisms of attentional deficits involved in visual extinction and neglect.  相似文献   
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This paper addresses the initial development of the first punched-card system in the United States in the 1880s and the construction of the next punched-card machine generation, launched in 1907. Finally, aspects of punched-card systems in the 1910s give a perspective on this history  相似文献   
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The influence of CsA withdrawal on the glomerular filtration rate (GFR) and the effective renal plasma flow (ERPF) was prospectively studied in nine stable liver transplant recipients. Before CsA withdrawal (test 1), and 6 months thereafter (test 2) the renal function was determined by measuring GFR and the ERPF with 125I-iothalamate and 131I-hippuran respectively. The renal function was also stimulated with dopamine, with an amino-acid infusion and a combination of both. After CsA withdrawal the GFR increased, median from 74 ml min-1 to 90 ml min-1, (P < 0.04). The ERPF also increased, median from 310 ml min-1 to 380 ml min-1, (P < 0.03). In test 1 as well as in test 2 the renal function could be stimulated, especially with dopamine. GFR and ERPF improved, even after more than 2 years of CsA treatment. These results suggest that long-term CsA treatment impairs the renal function, though in these liver transplant patients CsA treatment did not prevent afferent and efferent arteriolar vasodilatation after renal stimulation. This reversible intrarenal vasoconstriction during CsA treatment may predict renal improvement after CsA withdrawal.  相似文献   
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