三种油料作物对土壤Pb污染的耐受性与积累

为了选取具有修复Pb污染土壤潜力的油料作物,采用盆栽实验考察了不同浓度Pb(100、250、500、1000 mg·kg^(−1))处理下3种常见油料作物(大豆、向日葵和油菜)对Pb的耐受性和积累能力的差异,并对经济性进行评估.3种油料作物生长、光合、Pb积累及含油率的结果显示,100 mg·kg^(−1) Pb对3种油料作物生长无影响.在250—1000 mg·kg^(−1) Pb处理下大豆生长最好,其次是向日葵和油菜.随土壤中Pb浓度升高,Pb对3种油料作物的不利影响表现为,初始荧光F0呈现增加趋势而净光合速率Pn、潜在光合活性Fv/F0、PSII最大光化学量子产量QY_max呈现降低趋势.另外,大豆光合参数变幅最小,反映其对Pb的耐受性强于向日葵和油菜.3种油料作物对Pb的积累与Pb处理浓度显著相关,地上部Pb积累量均高于根,且大豆最高,向日葵次之,油菜最低.所有Pb处理下,大豆籽实中含油率与对照相比无显著变化.大豆籽实中Pb含量低于向日葵和油菜,符合饲料卫生标准.综上,基于比较3种油料作物在相同生长时期内,对Pb的耐受和积累能力以及经济价值实现的可能性,大豆可以被认为是修复Pb污染土壤的合适选择.

Hotspots and difficulties of biliary surgery in older patients

With the accelerated aging society in China,the incidence of biliary surgical diseases in the elderly has increased significantly.The clinical characteristics of these patients indicate that improving treatment outcomes and realizing healthy aging are worthy of attention.How to effectively improve the treatment effect of geriatric biliary surgical diseases has attracted widespread attention.This paper reviews and comments on the hotspots and difficulties of biliary surgery in older patients from six aspects:(1)higher morbidity associated with an aging society,(2)prevention and control of pre-operative risks,(3)extending the indications of laparoscopic surgery,(4)urgent standardization of minimally invasive surgery,(5)precise technological progress in hepatobiliary surgery,and(6)guarantee of peri-operative safety.It is of great significance to fully understand the focus of controversy,actively make use of its favorable factors,and effectively avoid its unfavorable factors,for further improving the therapeutic effects of geriatric biliary surgical diseases,and thus benefits the vast older patients with biliary surgical diseases.Accordingly,a historical record with the highest age of 93 years for laparoscopic transcystic common bile duct exploration has been created by us recently.