Past seawater experience enhances subsequent growth and seawater acclimability in a later life stage in rainbow trout Oncorhynchus mykiss

Fisheries Science - In the present study, we attempted to investigate the effects of temporal seawater experience on subsequent growth and later seawater acclimability in rainbow trout. To...     

缓释、控释肥料对大豆产量的影响

利用缓释或控释肥料，在盆栽条件下研究了大豆生育期间干物质积累，分配，养分吸收和产量的变化。结果表明，生育期间的总干物质的积累，结英期以前所有缓释肥料处理的均高于对照，尤以LP-40和LP-70的处理作用明显，而结荚后只有LP-40，LP-70和LP-SS100A3个处理的干物重高于对照；缓释时间短的肥料对氮素的吸收影响不大，而时间长的则减少前期的吸收，然而，缓释或控释肥料均能一定程度的增加K^ 的含量，但对PO4^3-影响不大。控释肥料LP-SS100A可增产21.9%，而缓释肥料LP-70和LP-180A分别增产13.1%和12.2%。     

Relationship of Cell Proliferating Marker Expressions with PGE(2) Receptors in Regenerating Rat Renal Tubules after Cisplatin Injection

Cisplatin, an anticancer drug, is well known to have nephrotoxicity as an adverse effect. We investigated the expressions of cell cycle markers and prostaglandin E(2) (PGE(2)) receptors (EP) in the affected renal tubules in rats injected with a single dose (6 mg/kg body weight) of cisplatin. On days 1-3 after dosing, the affected renal epithelial cells were almost desquamated, showing necrosis. On day 5 onwards, the renal tubules were rimmed by flattened or cuboidal epithelial cells with basophilic cytoplasm; BrdU-immunopositive cells began to significantly increase, indicating regeneration. Simultaneously, TUNEL-positive apoptotic cells were also seen. On days 1-5, cyclin D1-immunopositive cells were decreased with an increased expression in p21 mRNA, indicating G(1) arrest in the cell cycle. The affected renal epithelial cells began to react to EP4 receptor, but not to EP2 receptor. Some EP4 receptor-reacting epithelial cells gave a positive reaction to BrdU or cyclin D1. Collectively, the affected renal tubules underwent various alterations such as necrosis, apoptosis, regeneration and G(1) arrest; the aspects might be influenced by endogenous PGE(2) through EP4 receptor.