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991.
992.
993.
The blood of the Mexican bean beetle (Epilachna varivestis) contains a homotropane alkaloid, euphococcinine (1). The beetles 'reflex bleed' when disturbed, thereby deploying the alkaloid, which is provenly deterrent to spiders and ants. Newly emerged adults lack the alkaloid, but the compound builds up to deterrent levels in their blood within days. Eggs and larvae of Epilachna are devoid of the compound. 相似文献
994.
Summary The phenetic relationships between the families of the Hamamelididae subclass were studied by using the following multifactorial analytical methods: principal components analysis (PCA) and reciprocal averaging (RA). The results obtained agree appreciably with Takhtajan's classification system.
Remerciements. Nous remercions Mlle Sylvie Laliberté, Institut botanique de l'Université de Montréal, pour sa révision du manuscrit; M. Michel Labrecque, Institut botanique de l'Université de Montréal, pour avoir dessiné les figures; de même que M. André Bouchard, Jardin Botanique de Montréal et Institut botanique de l'Université de Montréal, de nous avoir permis d'utiliser les programmes dont il se sert pour ses travaux d'écologie. 相似文献
Remerciements. Nous remercions Mlle Sylvie Laliberté, Institut botanique de l'Université de Montréal, pour sa révision du manuscrit; M. Michel Labrecque, Institut botanique de l'Université de Montréal, pour avoir dessiné les figures; de même que M. André Bouchard, Jardin Botanique de Montréal et Institut botanique de l'Université de Montréal, de nous avoir permis d'utiliser les programmes dont il se sert pour ses travaux d'écologie. 相似文献
995.
The renal heamodynamic effects of a single i.v. administration of tolamolol were studied in 9 hypertensive subjects. No change of GFR and ERPF was observed after tolamolol, while urine output decreased and urine creatinine concentration increased. A reduction of the heart rate was confirmed. Blood pressure was unchanged. 相似文献
996.
997.
Sensory deprivation produced by removing the eyes and olfactory bulbs in male rats allowed pinealectomy to markedly augment the post-adrenalectomy elevation of ACTH levels. Pineal removal or sensory deprivation separately did not have this effect. Thus, intact sensory input and an intact pineal gland are independently capable of restricting the post-adrenalectomy rise in ACTH levels. 相似文献
998.
G. E. Risinger K. Karimian St. Jungk J. B. Simpson 《Cellular and molecular life sciences : CMLS》1978,34(9):1121-1122
Summary New biosynthetic pathways for the irregular terpenes, artemisia ketone and bakuchiol, are proposed. It is suggested that 2-(1-hydroxy-3-methylbutyl)thiamine and 2-(1-hydroxy-2-phenylethyl) thiamine are key intermediates in the biosyntheses of artemisia ketone and bakuchiol, respectively. 相似文献
999.
1000.
Cellular responses to mild heat stress 总被引:12,自引:0,他引:12
Since its discovery in 1962 by Ritossa, the heat shock response has been extensively studied by a number of investigators to understand the molecular mechanism underlying the cellular response to heat stress. The most well characterized heat shock response is induction of the heat shock proteins that function as molecular chaperones and exert cell cycle regulatory and anti-apoptotic activities. While most investigators have focused their studies on the toxic effects of heat stress in organisms such as severe heat stress-induced cell cycle arrest and apoptosis, the cellular response to fever-ranged mild heat stress has been rather underestimated. However, the cellular response to mild heat stress is likely to be more important in a physiological sense than that to severe heat stress because the body temperature of homeothermic animals increases by only 1–2°C during febrile diseases. Here we provide information that mild heat stress does have some beneficial role in organisms via positively regulating cell proliferation and differentiation, and immune response in mammalian cells.Received 14 May 2004; received after revision 2 August 2004; accepted 16 August 2004 相似文献