云南哀牢山平河黑长臂猿栖息地乔木结构分析

采用样方方法对栖息于云南省哀牢山平河(E 101°17′16.1″,N 24°20′09.5″,海拔2 600 m)的黑长臂猿(Nomascus concolor)栖息地乔木层结构进行了调查.调查中共记录到乔木57种隶属于23科37属;木质藤本植物9种隶属于6科8属.优势科主要为杜鹃花科(Ericaceae)、木兰科(Magnoliaceae)、山茶科(Theaceae)和壳斗科(Fagaceae)植物.主要树种重要值排序表明,露珠杜鹃(Rhododendron irroratum)为该地区最主要的优势种,在各坡位中均有广泛分布.乔木的多样性指数、均匀度指数在沟底明显降低,而乔木1层和2层所占的比例以及木质藤本的平均多度均随着坡位的下降而升高.与其他地区的长臂猿相比,哀牢山黑长臂猿的活动程度较低(10-22 m),果实性食物种类较少.

西南地区社鼠的亚种分化兼二新亚种描记

系统整理了我国西南及其邻近地区的社鼠标本,主成分分析(PC)和判别分析(DA)的结果也表明上述两地的标本都各自形成一个有别于指名亚种的类群,故分别将上述两地的标本订为2新亚种:雅江亚种(N. c. yajianensis subsp.nov.)和德钦亚种(N.c.deqinensis subsp.nov.)。由此确立了西南地区原社鼠指名亚种至少应分为3个亚种。

Dispersion, population dynamics and stock assessment of Caspian Sea prawns, genus Palaemon in Guilan Province coastal waters

Biological aspects, population dynamics and stock assessment of the Caspian Sea prawns Palaemon adspersus and Palaemon eleganse were investigated in Guilan coastal water of the Caspian Sea. Sampling was done monthly with a bottom trawl with mesh size of 3 mm in cod end in 0 - 5 m and 5 - 10 m depth in areas as Astra, Shafa Roud, Anzali, Chonchanan Chamkhaleh and Chaboksar during year 2002. Results of one year sampling showed that mean total length of Palaemon adspersus (pooled data) was 39.9±6.84 mm (X±SD) and mean wiegth was 1.133±0.67 g. The mean total length of females and males was 41.6±7.5 mm and 37.9±5.2 mm respectively and mean weight for the mentioned sexes was 1.353±0.65 g and 0.868±0.38 g respectively. There was significant differences in mean length and weight of females and males (P<0.05). The mean total annual sex ratio of males: females for this species was 1.4 and this sex ratio deviated significantly from 1:1 (X2, P<0.05) and biased towards males in the population of this species. The spawning season of Palaemon adspersus begins in April and ends in September with a peak in June . Mean fecundity of this species was 1994.5 ± 506.6 . The growth coefficients Loo and K for females were estimated as 58.5 mm and 2.3 /Year and for males as 55.9 mm and 2.6 /year respectively . The mean CPUA ( catch / Km2 ) for this species was 9.99 ± 33.2 kg / km2 and the correspondance biomass was calculated as 5067.7 kg in 0 - 10 m depth . The mean total length of Palaemon elegans (pooled data ) was 27.5 ± 5.7 mm (X±S.D) and mm and 24.01±4.18 mm respectively and mean weight for the mentioned sexes were was 0.553 ± 0.3 g and 0.237±0.15 g respectively. There was significant differences in mean length and weight of females and males (P<0.05). The mean total annual sex ratio of males:females for this species was 0.57 and in this species also sex ratio differed significantly from 1:1 (X2, P<0.05) and skewed towards females in the population of this species. The spawning season of Palaemon elegans extended from May to September with a peak in July . Mean fecundity of this species was 642.7±313.4. The growth coefficients LOO and K for females were estimated as 42.119 mm and 2.40 /Year and 33.87 mm and 2.50 /year for males respectively. The mean. CPUA ( catch/ Km2 ) for this species was 0.75±3.86 kg/km2 and the correspondance biomass was calculated as 382.1 kg in 0-10 m depth .

p53蛋白质Gly249和Ser249替换型三维结构的分子动力学研究

p53蛋白质核心区249位点精氨酸被其他残基替换后能引起p53蛋白质核心区L2、L3结构域间的密切联系趋于松散,正常的空间构象发生改变并使整个核心区结构稳定性受到破坏。

Ovulation in the tree shrew (Tupaia belangeri) induced by gonadotrophins

The induction of ovulation by exogenous gonadotrophins is an important approach for recovering oocytes used for studies on the reproductive biology of some mammals. In the present study, pregnant mare serum gonadotrophin (PMSG) and human chorionic gonadot

微囊藻毒素对束丝藻细胞生长和抗氧化系统的影响

为从活性氧(ROS)角度探讨微囊藻毒素(MC)导致藻类细胞死亡的机理及揭示藻细胞对MC诱发的氧化胁迫的响应机制,采用50和500μg·L-1的微囊藻毒素LR(MC-LR)处理束丝藻(Aphanizomenon sp. DC01)细胞,测定了细胞生长、细胞内活性氧(ROS)含量及抗氧化系统的变化.结果表明,50μg·L-1的MC-LR处理对藻细胞的生长无显著影响,而500μg·L-1的MC-LR处理可诱导藻细胞死亡.50μg·L-1的MC-LR处理的藻细胞ROS含量在处理第2d显著高于对照;但藻细胞能通过还

月湖近代生物硅沉积测定与营养演化的动态过程

在综合了国内外实验方法基础上,完善了湖泊沉积生物硅实验室测定方法。利用此方法,首次对一富营养化小型浅水湖泊——武汉市汉阳区月湖进行了2个柱状沉积物的生物硅含量测试。结果表明,生物硅可以反映月湖的营养演化的动态过程,130a前,湖泊受到的环境压力为轻;20世纪初期,月湖生物硅沉积缓慢上升,为水体富营养化开始发生时间;20世纪30年代至50年代,月湖已成为一富营养化湖泊;20世纪60年代至80年代,月湖水质持续恶化;20世纪80年代至月湖清淤前这段时期入湖污水增多,这加速了生物硅的沉积,正是这段时期使月湖最终

微囊藻毒素-RR对烟草细胞活力及营养生理的影响

采用0.1,1.0,10.0μg/mL的微囊藻毒素-RR(MC-RR)处理烟草BY-2悬浮细胞,测定了细胞活力、细胞内蛋白质含量、可溶性糖含量、硝态氮含量及总磷含量,并且检测了酸性磷酸酶(ACP)的活力变化情况.结果表明,中、高浓度毒素处理细胞2d后,细胞活力及蛋白质含量与对照相比均显著下降.高浓度MC-RR处理降低了胞内可溶性糖的含量,暴露2d后仅为对照的45.57%;低浓度MC-RR处理在后期增加了胞内可溶性糖含量.高浓度毒素处理细胞4d后,细胞内硝态氮含量显著低于对照;中、低浓度毒素处理细胞7d后降

鳜鱼病毒结构特征与形态发生

从患流行病的鳜鱼脾脏组织超微切片中观察到大量的病毒颗粒。该完整病毒颗粒直径约 135nm± 10 ,具包膜。成熟病毒核壳体约 90nm± 5 ,包膜厚度约 18nm± 3,核壳体与包膜间的非电子致密区约有 2 7nm± 2。通过对不同发病阶段发病鳜鱼脾脏组织切片的电镜观察 ,在感染初期的鳜鱼脾脏组织观察到病毒的吸附及典型的内吞入侵方式 ,在感染中后期的脾脏组织细胞质内观察到病毒发生基质及病毒核壳、包膜形成与病毒的释放。此外 ,在染病鳜鱼的肾、心、肝、及鳃组织亦观察到相同结构的病毒粒子。回接实验证实该病毒为