乳腺增生病p53基因第6外显子突变检测

目的 :探讨p5 3基因在乳腺癌发生早期的作用及早期诊断乳腺癌的分子病理指标。方法 :用PCR -SSCP检测36例乳腺单纯性增生、 31例不典型增生、 30例乳腺癌中p5 3基因第 6外显子突变 ,用DNA直接测序技术确定突变的碱基及其所在的密码子。结果 :乳腺单纯性增生、不典型增生、乳腺癌中p5 3基因第 6外显子的突变率分别为 0、6 5 % (2 / 31)、 13 3% (4/ 30 )。 6个点突变均为碱基替换 ,其中 4个发生于第 192密码子 (CAG→TAG) ,2个发生于第2 13密码子 (CGA→TGA) ,两者均导致多肽链合成提前终止。结论 :乳腺癌不典型增生中存在p5 3基因第 6外显子突变 ,该突变可能在乳腺不典型增生发展到乳腺癌过程中起重要作用 ,可作为早期诊断乳腺癌的辅助指标。

我国北方部分山羊品种mtDNA遗传多样性

我国北方地区有丰富的山羊品种遗传资源。这些遗传资源是人类赖以生存的宝贵基因库之一，是山羊育种不可缺少的重要的遗传材料。因此，对其遗传多样性进行研究具有十分重要的理论和实践意义。然而目前对这些山羊品种的遗传差异，特别是分子遗传的差异却知之甚少。本试验对中国北方地区部分山羊品种和类群的线粒体DNA的限制片段长度多态性进行了研究，以期为我国北方地区山羊品种的起源及遗传分化研究、群体的遗传结构和亲缘关系研究以及品种遗传资源的合理利用和保护研究提供基础资料和科学依据。

Molecular evolution of growth hormone gene family in old world monkeys and hominoids

Growth hormone is a classic molecule in the study of the molecular clock hypothesis as it exhibits a relatively constant rate of evolution in most mammalian orders except primates and artiodactyls, where dramatically enhanced rate of evolution (25-50-fold) has been reported. The rapid evolution of primate growth hormone occurred after the divergence of tarsiers and simians, but before the separation of old world monkeys (OWM) from new world monkeys (NWM). Interestingly, this event of rapid sequence evolution coincided with multiple duplications of the growth hormone gene, suggesting gene duplication as a possible cause of the accelerated sequence evolution. Here we determined 21 different GH-like sequences from four species of OWM and hominoids. Combining with published sequences from OWM and hominoids, our analysis demonstrates that multiple gene duplications and several gene conversion events both occurred in the evolutionary history of this gene family in OWM/hominoids. The episode of recent duplications of CSH-like genes in gibbon is accompanied with rapid sequence evolution likely resulting from relaxation of purifying selection. GHN genes in both hominoids and OWM are under strong purifying selection. In contrast, CSH genes in both lineages are probably not. GHV genes in OWM and hominoids evolved at different evolutionary rates and underwent different selective constraints. Our results disclosed the complex history of the primate growth hormone gene family and raised intriguing questions on the consequences of these evolutionary events. © 2005 Elsevier B.V. All rights reserved.

A STUDY ON THE EFFECT OF LESIONS OF AREA-7 OF THE PARIETAL CORTEX ON THE SHORT-TERM VISUAL SPATIAL MEMORY OF RHESUS-MONKEYS (MACACA-MULATTA)

This research is focused on the contribution of area 7 to the short-term visual spatial memory. Three rhesus monkeys (Macaca mulatta) were trained in the direct delayed response task in which 5 delay intervals were used in each session. When each monkey reached the criterion of 90% correct responses in 5 successive sessions, two monkeys underwent a surgery while the other one received a sham operation as a control. In the first stage of the surgery, bilateral areas 7a, 7b and 7ip of the parietal cortex of two monkeys were precisely lesioned. After 7 days of recuperation, the monkeys were required to do the same task. The average percentage of correct responses in the lesioned animals decreased from 94.7% to 89.3% and 93.3% to 82.0% respectively (no significance, P > 0.05, n = 2). In addition, the monkeys' complex movements were mildly impaired. The lesioned monkeys were found to have difficulty picking up food from the wells. In the second stage, bilateral area 7m was lesioned. In the 5 postoperative sessions, the average percentage of correct responses in one monkey, with a relatively precise 7m lesion, decreased from 94.7% to 92.2% (no significance, P > 0.05), while the other monkey, with widely spread necrosis of lateral parietal cortex, showed an. obvious decline in performance, but still over the chance level. After 240 trials this monkey reattained the normal criterion. The results of this research suggest that the lesions of area 7 of the parietal cortex did not significantly affect the short-term visual spatial memory, which has been shown to be sensitive to lesions of the prefrontal cortex; they also support the notion of dissociation of spatial functions in the prefrontal and parietal cortices.

The effect of acute stress on LTP and LTD induction in the hippocampal CA1 region of anesthetized rats at three different ages

Not all experiences are memorized equally well. Especially, some types of stress are unavoidable in daily life and the stress experience can be memorized for life. Previous evidence has showed that synaptic plasticity, such as long-term potentiation (LTP) that may be the major cellular model of the mechanism underlying learning and memory, is influenced by behavioral stress. However, the effect of behavioral stress on age-related synaptic plasticity in-vivo was primarily known. Here we found that the LTP induction in the hippocampal CA1 region of anesthetized rats obviously showed inverted-U shape related to ages (4, 10 and 74 weeks old rats), but low-frequency stimulation was unable to induce reliable long-term depression (LTD) in these animals. Furthermore, acute elevated platform (EP) stress enabled reliable LTD significantly and completely blocked LTP induction at these ages. Importantly, LTD after exposure to acute EP stress showed similar magnitude over these ages. The present results that stress enables LTD but impairs LTP induction at these three ages strengthen a view that stress experience-dependent LTD (SLTD) may underlie stress form of aberrant memories. (C) 2004 Elsevier B.V. All rights reserved.

中国角蟾亚科十一种的同工酶电泳研究(英文)

本文用同工酶电泳的方法分析了中国产角蟾亚科3属11种,共13个地理种群样本,以探讨它们的遗传多样性及系统关系。用于分析的酶共14种,由24个基因位点编码。经过酶带的分析和计算,得出了每个种群样本在每个基因位点上的等位基因频率（见表3）。根据基因频率的分布,计算得出了各种群样本的基因多样性指数——平均杂合率（H）（见表4）,结果表明,角蟾亚科的H值平均值为0.18, 在两栖动物中是属于很高的遗传多样性水平,根据基因频率的分布,计算了所有种群样本间的Nei’s遗传距（见表5）,并通过类平均法（UPGMA）重建了进化树（dendrogram）。分析结果支持将拟角蟾属（Ophryophryne）从角蟾属（Megophrys）中分出为独立属的观点;但是对短腿蟾属（Brachytarsophrys）是否为独立属提出了疑问。在角蟾属（Mesophrys）中,可以明显地看出3个组,它们中的种间亲缘关系比较近,这3个组分别是:①白颌大角蟾（M.lateralis）、大花角蟾（M.giganticus）和长肢角蟾（M.longipes）;②粗皮角蟾（M.palpebralespinneosa）、淡肩角蟾（M.boettgeri）...

艾滋病的传播与生殖道局部免疫

艾滋病的传播与生殖道局部免疫贲昆龙（中国科学院昆明动物研究所，昆明６５０２２３）引起人类艾滋病的人类免疫缺陷病毒（ＨＩＶ）可通过性交、血液、母婴和哺乳等方式传播，性交是主要的传播途径。据推测，全世界已感染ＨＩＶ的１，０００多万成年人当中，７５％是通过...

云南兔(Lepus comus)的染色体研究

用染色体分带技术分析表明云南兔2n=48, 常染色体中有6对中着丝点染色体、5对亚中着丝 点染色体、10对亚端着丝粒染色体和2对端着丝粒染色体。x染色体为一较大的亚中着丝粒染色体。c-带核型中, Nos.9,14,16,20染色体着丝粒c-带呈阴性, 而13,15,18呈很弱的阳性 。图版1表2参22(邓琳珠)

温度对烟蚜茧蜂发育、生殖的影响

烟蚜茧蜂发育速率与温度的关系符合逻辑斯蒂曲线,即25℃从卵至羽化所需历期最短(10.67d),30℃发育历期稍有延长(11.6d)。卵至羽化的发育起点温度为3.3℃,有效积温为266.0日度。烟蚜茧蜂雌蜂羽化当天即可产卵,在产卵期的前4天产出总卵量的90%(15-30℃);在6:30-22:30产出总卵量的80%。温度>25℃对烟蚜茧蜂雌蜂的寿命、生殖力,以及对僵蚜体重和羽化率均造成显著的负影响。烟蚜茧蜂雌蜂的寿命、性比、生殖力及僵蚜的体重和羽化率均在20℃时达最佳,结合发育历期的结果,认为该蜂大规模人工繁殖和释放的最佳温度范围是20-25℃。就研究结果在生物防治中的应用也进行了讨论。

Sleeping sites of black-and-white snub-nosed monkeys (Rhinopithecus bieti) at Baima Snow Mountain, China

Data on sleeping sites of a group of black-and-white snub-nosed monkeys Rhinopithecus bieti (Colobinae, Primates) were collected between April-July and September-December 2001 to try to determine the factors affecting site selection at Nanren (99 degrees