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81.
Historical comparison of oracles in west Africa, mainly during the nineteenth century, shows how divination practices may alter. In the cases explored here, reputation, range of users, economic growth, and political influence interacted as these oracles developed; some at sites with internal and overseas trade access became complex, large-scale operations. But by about 1900, colonialists felt threatened by their secular and their spiritual power and smashed them physically, though not spiritually. Contextualized comparison shows that the many people who were involved as oracle organizers and supplicants must have had different motivations and interests. Some methodological implications of the findings are considered. As in many powerful secular organizations, access to insider knowledge was blocked, but oracular reputation was important, and the oracles had competitors. Success derived partly from collecting intelligence, with simultaneous advertisement that emphasized the mysterious power of their operations. 相似文献
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Expression of an ABA-induced gene of tomato in transgenic tobacco during periods of water deficit 总被引:9,自引:1,他引:8
The gene le25 is an abscisic acid (ABA)-induced gene of tomatowhich is expressed both in wilted vegetative organs and developingseeds. Spatial and temporal expression was analysed in tobaccoplants transformed with a chimeric gene in which 5'-upstreamDNA sequences of le25 were fused to the E. coli uidA gene, whichencodes ß-glucuronidase (GUS). Histochemical stainingrevealed that GUS was expressed in all tissues of vegetativeorgans in response to water deficit. Exogenous ABA induced expressionto a lesser extent, even though ABA content was the same asdroughtstressed leaves, indicating a difference in responseto endogenous ABA compared to exogenous ABA. Water-deficit-inducedGUS expression in floral tissues was examined in pre-anthesisfloral buds from four different stages (IIV; 11, 16,33, 49 mm bud length, respectively). While non-stressed floralorgans showed no GUS activity except in pollen at stages IIIand IV, GUS activity was water-deficit-induced in sepals ofall stages, petals of stage II, and stigmas of stage II andIII. In seeds, GUS activity was detected in both the embryoand endosperm at 15 d post-anthesis, which coincided with alarge increase in the concentration of ABA in the seed. In transgenicplants, the le25 5'-flanking DNA drove expression of GUS duringwater deficit in two modes: non-tissue-specific expression invegetative organs, and tissue-specific expression in reproductiveorgans. The location of GUS activity indicated that ABA concentrationis elevated throughout the tissues of the leaf during periodsof water deficit. Key words: Tomato, ABA, drought stress, lea gene, water deficit 相似文献
84.
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86.
Role of inhibition of nitric oxide production in monocrotaline-induced pulmonary hypertension 总被引:1,自引:0,他引:1
Mathew Rajamma; Gloster Elizabeth S.; Sundararajan T.; Thompson Carl I.; Zeballos Guillermo A.; Gewitz Michael H. 《Journal of applied physiology》1997,82(5):1493-1498
Mathew, Rajamma, Elizabeth S. Gloster, T. Sundararajan, Carl I. Thompson, Guillermo A. Zeballos, andMichael H. Gewitz. Role of inhibition of nitric oxide productionin monocrotaline-induced pulmonary hypertension. J. Appl. Physiol. 82(5): 1493-1498, 1997.Monocrotaline (MCT)-induced pulmonary hypertension (PH) isassociated with impaired endothelium-dependent nitric oxide(NO)-mediated relaxation. To examine the role of NO in PH,Sprague-Dawley rats were given a single subcutaneous injection ofnormal saline [control (C)], 80 mg/kg MCT, or the same doseof MCT and a continuous subcutaneous infusion of 2 mg · kg1 · day1of molsidomine, a NO prodrug (MCT+MD). Two weeks later, plasma NO3 levels, pulmonary arterialpressure (Ppa), ratio of right-to-left ventricular weights (RV/LV) toassess right ventricular hypertrophy, and pulmonary histology wereevaluated. The plasma NO3 level inthe MCT group was reduced to 9.2 ± 1.5 µM(n = 12) vs. C level of 17.7 ± 1.8 µM (n = 8; P < 0.02). In the MCT+MD group,plasma NO3 level was 12.3 ± 2.0 µM (n = 8). Ppa and RV/LV in theMCT group were increased compared with C [Ppa, 34 ± 3.4 mmHg(n = 6) vs. 19 ± 0.8 mmHg(n = 8) and 0.41 ± 0.01 (n = 9) vs. 0.25 ± 0.008 (n = 8), respectively;P < 0.001]. In the MCT+MDgroup, Ppa and RV/LV were not different when compared with C [19 ± 0.5 mmHg (n = 5) and 0.27 ± 0.01 (n = 9), respectively;P < 0.001 vs. MCT]. Medial wall thickness of lung vessels in the MCT group was increased comparedwith C [31 ± 1.5% (n = 9)vs. 13 ± 0.66% (n = 9);P < 0.001], and MDpartially prevented MCT-induced pulmonary vascular remodeling [22 ± 1.2% (n = 11);P < 0.001 vs. MCT and C].These results indicate that a defect in the availability of bioactive NO may play an important role in the pathogenesis of MCT-induced PH. 相似文献
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88.
Allen D. Ziebur 《Theoretical population biology》1984,26(3):315-319
P. H. Leslie (1945, Biometrika, 33, 183–212) (and others) introduced vector-matrix growth difference equations to model populations in which birth and death rates are age-dependent. We develop differential versions of these equations in both the unrestricted growth and logistic cases. We find that the vector logistic equations (difference and differential) are explicitly solvable in terms of solutions of the unrestricted equations, even when vital rates vary with time. These explicit solution formulas make it easy to determine the behavior of solutions as time goes on. 相似文献
89.
Production of Viscous Dextran-Containing Whey-Sucrose Broths by Leuconostoc mesenteroides ATCC 14935 下载免费PDF全文
Viscous broths were produced by growing Leuconostoc mesenteroides on a medium containing whey supplemented with sucrose. When combined with similarly produced xanthan-containing broths, a synergistic increase in viscosity was observed. 相似文献
90.
Douglas L. Vizard R.Allen White Allen T. Ansevin 《Archives of biochemistry and biophysics》1984,229(2):498-508
High-resolution thermal denaturation was used to measure the heterogeneity within repeated DNA sequences. An analysis of combined denaturation/redenaturation experiments on mouse satellite DNA suggests the existence of two minor components, one of which does not appear in the prepared EcoRII monomer. The resolving power of the denaturation/redenaturation experiment is estimated and contrasted with that of the reassociation experiment, often used to estimate repeated sequence heterogeneity. A mathematical model of the redenaturation experiment was developed and applied to mouse satellite data; the results suggest that only one-fourth of the mismatched base pairs are energetically significant in the reduction of heteroduplex stability. 相似文献