A new anti-HIV lupane acid from Gleditsia sinensis Lam.

A new lupane acid, 2 beta-carboxyl, 3 beta-hydroxyl-norlupA (1)-20 (29)-en-28-oic acid (1), together with five known lupane acid derivatives (2-6), were isolated from the stings of Gleditsia sinensis Lam.. Their structures were elucidated on the basis of

Estimation of RNA/DNA ratio in two north-Indian natural populations of mahseer (Tor tor) and its relationship with growth and hydrobiology

Samples of Tor tor were collected from Bari Reservoir of Udaipur and Narmada River at Hoshangabad (India), in the months of July and November 2005, respectively. Twenty-five samples were collected from each location. Bari Reservoir samples ranged from 17.0 to 24.5 cm in total length and from 75 to 155 g in weight, while Narmada samples ranged from 20.0 to 42.0 cm in length and 90 to 425 g in weight. The nucleic acid content in body muscle of Tor tor and the RNA/DNA ratio were estimated. The age of fishes was estimated by the scale study method and specimens were classified into four age groups. RNA/DNA ratio showed significant linear increase with increase in weight and age till the age of three years after which, the growth rate reduced. The 1-2 year group was the only one common between the two water bodies and a comparison of RNA/DNA ratios showed higher growth rate in Bari Reservoir. The gross primary productivity was also higher in Bari Reservoir being 551 mg cmˉ³ dˉ¹ compared to 404 mg cmˉ³ dˉ¹ observed for Narmada River. The condition factor (K) was found to be higher (1.21) in the fish from the Bari Reservoir compared to those of Narmada River (1.14). The growth rate was higher in females compared to males in >100 g specimens.

浙江地方猪种遗传多样性研究

采用蛋白电泳和线粒体DNA RFLP分析方法,研究了浙江七个地方品种猪及浙江野猪的遗传多样性状况。从分析的30个遗传座位、99个地方品种个体中发现MDH,PEPB,6PGD,AK,ADA,PHI六个座位具有多态性,其中AK,MDH多态座位在家猪中首次发现。浙江地方猪种的亲缘关系很近。在mtDNA RFLP水平,25种限制性内切酶在27个地方品种个体及3个野猪个体中共检出30种限制性态型,可归结成三种单倍型。各单倍型间平均遗传距离(P)为0.005,群体平均多态度(#pi#))为0.000 8,处于遗传多样性贫乏范围。

Occurrence of milkfish, Chanos chanos (Forsskal) eggs around Panay Island, Philippines

The study documents the occurrence of milkfish, Chanos chanos (Forsskal) eggs around Panay Island, Philippines: in Cuyo East Pass, Panay Gulf, Visayan Sea, Sibuyan Sea and Cagayan Islands. Most of the eggs, 545 out of 551, were obtained from Cuyo East Pass compared to Cagayan Islands and Sibuyan Sea while no milkfish egg was recovered from either Panay Gulf or Visayan Sea.

石榴干腐病生物生态学及发生流行规律和治理研究

云南蒙自石榴干腐病助故阮以菌丝体和分生抢子在僵果、干 腐果及其他感病部位越冬。翌年经风雨、昆虫和人为活动在果园广为传播。石榴 花、幼果、果实期均可感病发病, 等筒花丝最易感病。果实发病率达一, 重者达一。采取综合治理措施, 其中重要的是在首次连续降雨前利去干 花丝、套袋和树冠多次喷清水, 提前水解、淡化干花丝、伤口渗出液的微酸性度, 可 控制该病的发生危害, 危害率由原来的一现降为一。

一种鸡胚胎心率记录的新方法

鸡胚胎是一种被广泛应用于发育生物学研究的实验材料。在以鸡胚胎为动物模型的各项研究工作 中, 心率常被看作是一个很重要的反应胚胎生理活动指标。本文详细介绍了一种侵入性的心电记录新方法, 在 正常的生理条件下通过记录鸡胚胎心电的变化来监测心率。首先在蛋壳上钻孔, 将电极插人蛋内, 然后通过放 大器放大, 板转换, 将心电信号输人电脑进行分析处理, 提取与心率相关的信息。这种记录方式对胚胎损 伤较小, 不影响胚胎的正常发育具有灵敏度高, 操作简单, 容易掌握等特点。

小眼虫的核骨架研究

小眼虫细胞经轻度超声处理、选择性抽提后, 利用 DGD 包埋-去包埋剂电镜技术及 Western blot 分析技术对其核骨架、核纤层进行了研究. 结果显示: 细胞核内存在一个不被 DNase 所降解和热三氯醋酸所去除的纤维蛋白性网架结构; 核的周围有一层明显的核纤层结构; Western blot 分析表明其核纤层有两种阳性蛋白成分, 一为相当于高等真核细胞核纤层蛋白 lamin B 的强阳性成分, 另一为相当于 lamin A 的弱阳性成分, 但无相当于lamin C 的成分. 该文认为小眼虫这种低等的单细胞真核生物已具有了核骨架、核纤层结构, 其核纤层的蛋白组成应该代表了核纤层进化历程中早期的一个阶段。