外源亚精胺对盐胁迫下白刺幼苗叶片抗氧化酶系统的影响

为进一步阐明盐生植物白刺耐盐性与多胺的关系,通过水培试验研究了叶面喷施亚精胺(Spd)对不同浓度NaCl胁迫下西伯利亚白刺幼苗叶片丙二醛(MDA)和超氧阴离子(O2)产生速率,以及抗氧化物酶系统和根系活力的影响.结果表明:叶面喷施0.1 mmol·L1 Spd 5 d后,可显著提高100和200 mmol·L1 NaCl胁迫下白刺幼苗叶片超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)的活性以及根系活力,降低了叶片MDA含量和O2的产生速率;而在0、50、300 mmol·L-1 NaC1处理下,外施Spd对白刺幼苗叶片上述指标无显著影响.研究结果证实,在100～200 mmol·L-1 NaCl胁迫范围内,外施亚精胺可能通过增强体内保护酶活性来显著降低活性氧水平,有效减轻盐胁迫对盐生植物白刺幼苗造成的过氧化伤害,从而增强白刺对盐环境的适应性.     

昆仑岩黄耆(豆科)在中国的分布

报道了豆科Leguminosae昆仑岩黄耆Hedysarum krassnovii B．Fedtsch．在中国的分布。昆仑岩黄耆与近缘种红花岩黄耆H.multijugum Maxim.形态易混淆,但以其小叶3-9×3-7mm;旗瓣倒卵形,顶端凹陷约2mm深;翼瓣狭披针形;龙骨瓣近半圆形或矩圆形;花萼二唇彤;荚果具1-2节荚等性状易于区分。另外,此二种的物候期、生境及地理分布亦有区别。     

冷蒿草原土壤可萌发种子库特征及其对放牧的响应

（１）采用萌发试验法对内蒙古冷蒿（Ａｒｔｅｍｉｓｉａ ｆｒｉｇｉｄａ）草原土壤种子特征及其在不同放牧压力下的变化进行了研究。（２）冷蒿草原可萌发种子库由４种多年生禾草,１１种种多年生杂草及３种１年生植物所组成。（３）每样中的可萌发种子是变化于４５到３０５之间,平均１０２／样。多年生禾草、多年生杂类草及１年生植物的土壤中种子量分别占总可萌发种子库的４６．５７％、５１．９６％和１．５７％。多年和禾 草     

耐低温产甲烷菌的分离及其产气活性的初探

在青藏高原地区的低温条件下通过滚管技术分离了一类耐低温产甲烷菌,并利用气相色谱法测定了产气活性。结果表明:这类甲烷菌最低产气温度为8℃,甲烷气体产生的高峰期在厌氧培养的第7 d;pH值与盐浓度对其产气活性均有影响,最佳条件为pH值7.0、盐度4%。     

“山水林田湖草沙生命共同体”耦合框架、模型与展望

“山水林田湖草沙生命共同体”系统保护与修复是我国生态文明建设的重要内容。明确生命共同体的耦合机制,是科学地进行生态保护和修复工作的关键。针对当前生命共同体耦合机制不清、理论和方法不健全的问题,从耦合的视角出发,在小流域尺度上单一生态系统内部生态要素的耦合、流域尺度上不同生态系统之间的耦合、区域尺度上人与自然的耦合三个方面进行整合,在此基础上探讨了多尺度山水林田湖草沙耦合理论,提出了一般性的山水林田湖草沙耦合理论框架。梳理并比较了当前主要的生态系统模型、景观模型、统计学模型以及复合生态系统的多模型耦合方法,综合提出了一个适用于"山水林田湖草沙生命共同体"耦合研究方法。对进一步完善山水林田湖草沙一体化保护修复提出了建议,包括：一是构建多源信息数据库,推进定量化耦合机制研究;二是开展全生命周期监测与评估,探索适应性治理路径;三是强化多元主体参与,完善协同保护机制。     

Bilateral detection thresholds in dextrals and sinistrals reflect the more sensitive side of the nose, which is not lateralized [published erratum appears in Chem Senses 1998 Dec;23(6):761]

Several fundamental questions remain enigmatic concerning human olfactory sensitivity, including (i) whether detection threshold differences exist between the two sides of the nose (and, if so, whether such differences are influenced by handedness) and (ii) whether bilateral (i.e. binasal) stimulation leads to lower thresholds than unilateral stimulation (and, if so, whether the degree of facilitation is inversely related to general olfactory ability). In this study, and well-validated single staircase procedure was used to establish bilateral and unilateral detection thresholds for the cranial nerve I stimulant phenyl ethyl alcohol in 130 right- and 33 left-handed subjects. No differences in sensitivity between the left and right sides of the nose were observed in either group. Bilateral thresholds were lower, on average, than unilateral thresholds when the latter were categorized in terms of left and right nares. However, the bilateral thresholds did not differ significantly from those of the side of the nose with the lower threshold. Overall smell ability, as measured by the University of Pennsylvania Smell Identification Test, did not interact with any of the test measures. These data imply that (i) the left and right sides of the nose do not systematically differ in detection threshold sensitivity for either dextrals or sinistrals and (ii) if central integration of left:right olfactory threshold sensitivity occurs, its effects do not exceed the function of the better side of the nose.      

云南瓶尔小草属一新种

Ophioglossum yongrenense Ching ex Z. R. He et W. M. Chu, sp. nov.Species nova aspectu inter O. kawamuram Tagawa et O. parvum Nishida et Kurita Japonicae, differt a priore frondibus pro parte laminis sterilibus praeditis (in illa frondibus omnino laminis sterilibus non praeditis), a posteriore frondibus pro parte laminis sterilibus non praeditis (in O. parvo Nishida et Kurita frondibus omino laminis sterilibus praeditis).……     

Polypharmacy in the management of patients with schizophrenia on risperidone in a tertiary-care hospital in Malaysia

The present study was conducted primarily to determine the occurrence of polypharmacy in patients with schizophrenia on risperidone. The secondary aim was to ascertain the incidence of inappropriate prescribing with anticholinergics. A retrospective review of the medical records of all patients who were being followed up at the out-patient clinic of a tertiary-care hospital in Malaysia was conducted. Only patients who were being prescribed risperidone between 1 June 2008 and 31 December 2008 were included in the study. Demographic data such as patient’s age, gender and race were obtained from the patient’s medical records. In total, 113 patients met the selection criteria. Polypharmacy was found to occur in 34 patients (30.09%), with the majority (76.47%) being on two antipsychotics. In total, 27 patients (34.18%) on monotherapy with risperidone were prescribed an anticholinergic on scheduled dosing, while 19 patients (24.05%) were prescribed it on an as-needed basis. Of the patients on polypharmacy, 26 (76.47%) were on scheduled dosing of anticholinergics, while three (8.82%) were taking the medication on an as-needed basis. Polypharmacy should be avoided, and the use of anticholinergics should be closely reviewed. By adopting more efficient prescribing practices, costs can be reduced and financial resources can instead be channelled towards more beneficial areas for the patients.     

Capping protein is essential for cell migration in vivo and for filopodial morphology and dynamics

Capping protein (CP) binds to barbed ends of growing actin filaments and inhibits elongation. CP is essential for actin-based motility in cell-free systems and in Dictyostelium. Even though CP is believed to be critical for creating the lamellipodial actin structure necessary for protrusion and migration, CP''s role in mammalian cell migration has not been directly tested. Moreover, recent studies have suggested that structures besides lamellipodia, including lamella and filopodia, may have unappreciated roles in cell migration. CP has been postulated to be absent from filopodia, and thus its role in filopodial activity has remained unexplored. We report that silencing CP in both cultured mammalian B16F10 cells and in neurons of developing neocortex impaired cell migration. Moreover, we unexpectedly observed that low levels of CP were detectable in the majority of filopodia. CP depletion decreased filopodial length, altered filopodial shape, and reduced filopodial dynamics. Our results support an expansion of the potential roles that CP plays in cell motility by implicating CP in filopodia as well as in lamellipodia, both of which are important for locomotion in many types of migrating cells.