植物氮素营养与病害发生关系研究进展

氮素营养不仅影响植物的正常生长发育,还会影响植物的感病性或抗病性。该文主要综述了氮素营养及其代谢对植物病害发展的影响、诱导病原菌侵染的寄主氮营养信号和氮素营养对植物与病原菌互作相关基因表达的影响,尤其是氮素受限(饥饿)对病原菌基因的诱导表达、植物衰老基因和抗病基因的关系、植物衰老过程中防御基因的表达等国际研究的热点领域所取得的成果和进展,并讨论了有待深入研究的问题。     

肠内营养支持对克罗恩病营养障碍患者IGF-I、IGF-IR及IGFBP-5水平的影响

目的:探讨肠内营养支持对克罗恩病营养障碍患者血清IGF-I、IGF-IR及IGFBP-5水平的影响。方法:选取我院收治的克罗恩病患者92例,根据治疗方法不同分为对照组及治疗组,每组各46例。对照组予以美沙拉嗪和醋酸泼尼松龙片常规治疗,治疗组在对照组基础上加用肠内营养混悬液静脉滴注。观察并比较两组患者治疗前后血清中IGF-I、IGF-IR及IGFBP-5水平的变化情况。结果:与治疗前比较,两组患者治疗后血清IGF-I、IGF-IR及IGFBP-5水平明显降低,差异具有统计学意义(P0.05);与对照组比较,治疗组患者治疗后血清IGF-I、IGF-IR及IGFBP-5水平明显降低,差异具有统计学意义(P0.05);与对照组比较,治疗组患者治疗后的营养状况明显改善,临床总有效率明显提高,差异具有统计学意义(P0.05)。结论:肠内营养支持能够降低克罗恩病营养障碍患者血清中IGF-I、IGF-IR及IGFBP-5水平,改善肠纤维化和营养状态,提高临床疗效。     

Nutrition, fertility and maternal investment in primates

While the energetics of reproduction have been intensively investigated among women, studies of mother-offspring relationships among non-human primates have tended to neglect the effect of nutrition of the mother on lactational performance and on growth and survival of offspring. Typically fertility has been compared between populations under different nutritional regimes. In this paper, the relations between suckling frequencies, the time of weaning, the survivorship of offspring, the contraceptive effects of lactation and the quality of maternal diets are outlined. Energy transfer from mother to offspring in the form of milk is proposed as a measurable component of maternal investment, and the behavioural causes and consequences of lactational anoestrus are explored using data from free-ranging vervet monkeys. It is suggested that nutrition of the mother is most important during the early phase of rapid infant growth, because at that time the energetic requirements of lactation are high; and that a mother's ability to assess her infant's demands and needs for nutrition for growth leads to alterations in suckling frequencies which result in variation in female fertility.     

Nutrition, metabolism and colorectal cancer

Colorectal cancer and myocardial infarction are associated at population level and in autoptic studies. Furthermore, they share many blood variables: cholesterol, triglycerides and HDL cholesterol, fructosamine, glycated haemoglobin and glycated apolipoprotein B. These blood variables are intermediates between dietary, mainly saturated fats and high glycemic index and load diets, and colorectal cancer and myocardial infarction. Blood intermediate variables can be used in dietary trials as outcomes, and even to throw light on the pathogenesis of both diseases.