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991.
992.
The effect of various growth regulators on the atrophy of terminal flower buds was tested on Baccara roses. Treatments with gibberellic acid (GA) and 2-chloroethyl trimethyl ammonium chloride (CCC) reduced the atrophy of the flowers. The application of 2-chloroethyl phosphonic acid (CEPA) to the buds enhanced abortion, and the effect was more marked on the lower than on the upper shoot. The stage most sensitive to CEPA was when the shoots were 8–35 cm long. Treatment with abscisic acid (ABA) had no effect of the degree of “blindness”, nor did kinetin applied to the apex affect flowering. Spraying with benzyl adenine increased both the rate of sprouting of the lateral buds and the extent of “blindness” of the sprouting shoots, but did not reduce the number of flowers per branch. 相似文献
993.
H E Schroeder U Schroeder G Santibánez-H 《The Pavlovian journal of biological science》1986,21(1):16-24
This study analyzes so-called hopeless gaggers, i.e., patients in whom dental treatment and wearing of a prosthesis produced a retching or vomiting reaction, in order to investigate the sources and properties of this pathologic reaction. In 35 patients, an anamnestic inquiry, a determination of the reflexogenic zone, a recording of the peripheral pattern of the pathologic reflex, and extinction training were performed. A group of six normal persons served as a comparison group. It was shown that patients, in comparison with normals, had an enlarged receptive field, were sensitive to a broader population of stimuli, and showed precursors and aftereffects of the retching-vomiting not found in normals. This pathologic reaction was the symptom of different psychopathologic processes, such as specific fear, repugnance-fear-based disturbances, diffuse anxiety, goal-directed behavior, depressive states and, at least in one case, visceral pathology. The various patients differed with respect to properties of the reaction as well as in the sensitivity to the extinction procedure. It is discussed that different integrative nervous processes play a role in the origin and development of the syndrome: activation of unconditional reflexes, activation of classic and instrumental conditional reflexes, activation of such reflexes by an increase of the reactivity level of specific and unspecific structures of the brain, generalization of stimuli, etc. 相似文献
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J.H. Rodriguez S.B. Weller E.D. Wannaz A. Klumpp M.L. Pignata 《Ecological Indicators》2011,11(6):1673-1680
The air quality in agricultural areas close to industrial emission sources (chemical, metallurgical and cement plant) was evaluated through a biomonitoring study employing the epiphytic species Tillandsia capillaris Ruíz and Pav. f. capillaris. Plants were collected from a non-contaminated area in the province of Córdoba (reference site) and transplanted back to this site and into three industrial areas representing different emission sources of air pollutants: cement plant, chemical and metallurgical industries. Biomonitors were exposed to ambient air for four periods of 3 months each during one year (for determination of physiological parameters) and for four periods of 6 months each during two years (for determination of trace elements). In the exposure period coinciding with the winter season (i.e., the dry season) the plants showed the strongest global physiological damage, possibly due to higher air pollutant concentrations. The comparison among study areas indicates the highest values of foliar damage index at the chemical industries sites, possibly due to the emission of oxidizing pollutants. On the other hand, heavy metals and trace element concentrations (V, Fe, Co, Cu, Br, Ni, Zn and Pb) were associated mainly with metallurgical industries, although the chemical industries and the cement plant were associated with Ni, Zn and Ca accumulation in the biomonitor, respectively. Considering that these sites with high industrial activity are located close to soybean producing areas, further environmental and toxicological studies are necessary, taking into account food safety and human health. 相似文献
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999.
Dr. H. Sch. 《Plant Systematics and Evolution》1852,2(1):4-5
Ohne Zusammenfassung 相似文献
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