Pattern analysis of stem cell differentiation during <Emphasis Type="Italic">in vitro Arabidopsis</Emphasis> organogenesis

Plant somatic cells have the capability to switch their cell fates from differentiated to undifferentiated status under proper culture conditions, which is designated as totipotency. As a result, plant cells can easily regenerate new tissues or organs from a wide variety of explants. However, the mechanism by which plant cells have such remarkable regeneration ability is still largely unknown. In this study, we used a set of meristem-specific marker genes to analyze the patterns of stem cell differentiation in the processes of somatic embryogenesis as well as shoot or root organogenesis in vitro. Our studies furnish preliminary and important information on the patterns of the de novo stem cell differentiation during various types of in vitro organogenesis.     

糙叶败酱挥发油镇静作用的研究

本文观察了败酱科植物糙叶败酱(Patrinia scabra Bunge)根和根茎中制得的挥发油的镇静作用,井与黄花败酱挥发油做了比较。结果表明,此油灌胃给予数组小鼠,剂量0.45ml/kg,显示如下的作用:[1]能显著延长由于腹腔注射戊巴比妥钠(50mg/kg)引起的小鼠睡眠时间,但其作用强度弱于黄花败酱挥发油。(2)一次灌胃给予小鼠大剂量10.46g/kg的糙叶败酱挥发油,连续观察10天,动物外观正常,无一死亡,体重增加与对照组相似。     

鸽血变虫（Haemoproteus columbae Kruse,1980）生活史研究

本文首次报告我国鸽血变虫的生活史。自然和人工感染实验证明虱蝇是其昆虫媒介。本虫的配子体进入虱蝇体内6—10天后完成孢子有性增殖。 实验观察了本虫在鸽体内无性增殖期的形态、部位及在末梢血液中配子体的发育过程,并证明其潜隐期(prepatent period)为28—30天。 本工作亦对羽虱体腔中的卵囊和子孢子作了描述,提示羽虱也可能是本虫的媒介昆虫,有待今后研究证实。     

大豆结瘤突变体成分的初步分析及其对硝酸还原酶活性和结瘤的影响

超结瘤大豆（Ｇｌｙｃｉｎｅ ｍ ａｘ （Ｌ．） Ｍｅｒｒ．） ｎｔｓ ３８２ 和不结瘤大豆Ｎｏｄ ４９ 的叶和根组织水提取物经Ｓｅｐｈａｄｅｘ Ｇ２５ 过滤、洗脱,再根据洗脱物对硝酸还原酶（ＮＲ）活性的影响可划分为４ 个组分（ｆｒａｃｔｉｏｎ）样品,即ｎｔｓ ３８２（Ｎｏｄ ４９） Ｆ１、ｎｔｓ ３８２（Ｎｏｄ ４９） Ｆ２、ｎｔｓ ３８２（Ｎｏｄ ４９） Ｆ３ 和ｎｔｓ ３８２（Ｎｏｄ ４９） Ｆ４。其中, ｎｔｓ３８２ Ｆ２ 和Ｆ４ 抑制ＮＲ 活性作用在接种ＵＳＤＡ１１０ 后明显下降, 但接种的ｎｔｓ ３８２ Ｆ２ 却能提高大豆Ｂｒａｇｇ 的结瘤数达一倍, 而接种的ｎｔｓ ３８２ Ｆ３ 和Ｆ４ 的作用不明显。ＮＲ 活性抑制因子不是刺激结瘤的因子, 刺激结瘤的因子主要分布在接种的ｎｔｓ３８２ Ｆ２ 部分中。与这一现象相反, Ｎｏｄ ４９ Ｆ２ 和Ｆ４ 抑制ＮＲ活性的作用在接种后更强, 且也抑制大豆ｎｔｓ ３８２ 的结瘤, 其中Ｎｏｄ ４９ Ｆ４ 抑制结瘤的作用基本不能逆转。抑制结瘤因子主要分布在接过种的Ｎｏｄ ４９ Ｆ４ 部分中     

九种罕见的人类染色体异常核型报告

ReportonNineRareSpeciesofHumanChromosomalAbnormalKaryotypesHanWeitian;QuOu;YuPing;JiangMiao(LiaoningResearchInstituteofFamilyPlanning,Shenyang110031)自1983年以来,我们对数千例不育及胚胎丢失等生殖异常患者进行细胞遗传学研究,发现大量异常染色体核型,而且异常种类繁多,已报道世界首报人类异常核型25种[1]。最近,在不良妊娠患者中又发现9种异常核型,经湖南医科大学医学细胞遗传学国家培训中心鉴定,为世界首次报道．现报告如下。1病例摘要及核型例1男,30岁,表型及智力正常,其妻子妊娠两次,均在无任何诱因情…     

Mother-cub relationships in giant pandas in the Qinling Mountains,China, with comment on rescuing abandoned cubs

Six cases of mother-cub relationships in wild giant pandas (Ailuropoda melanoleuca) were observed in the Qinling Mountains, China. It was found that panda cubs are normally left alone in the den for 4–8 h while mothers forage. The mother's absence during bouts of foraging should be considered when rescuing abandoned cubs in order to avoid adding to the decline of the wild population. © 1994 Wiley-Liss, Inc.     

腺苷转运体亲和层析分离

本文合成了一种腺苷亲和层析凝胶,并采用亲和层析法从牛脑细胞膜上分离出了几种膜上结合的腺苷结合蛋白质。这些蛋白质在ＳＤＳ－ＰＡＧＥ电泳凝胶上为单一或主要的蛋白带,分子量分别为６４ｋｄ,４５ｋｄ,３５ｋｄ。腺苷转运体抑制剂潘生丁和ＮＢＭＰＲ对６４ｋｄ蛋白与＾３ｈ－腺苷的结合抑制作用远强于腺苷受体的激动剂ＮＥＣＡ和Ｒ－ＰＩＡ;这表明６４ｋｄ蛋白为牛脑细胞膜上结合的腺苷转运体。     

Site and mechanism of behavioral tolerance to cocaine: A study of dopamine release in Wistar-Kyoto and spontaneously hypertensive rats

Wistar-Kyoto and spontaneously hypertensive rats received i.v. infusions of cocaine hydrochloride (60 mg/kg per day) for 3, 7, and 14 days, or saline for 7 days. Acute cocaine challenge (40 mg/kg, s.c.) was given to treated and control rats 24 hr after the termination of each infusion period. There were no strain differences in brain levels of cocaine during cocaine infusion, nor after cocaine challenges. There were no strain differences in resting levels of [³H]dopamine release. Release of [³H]dopamine decreased in nuclei accumbens of 7- and 14-day cocaine-infused animals. Release of [³H]dopamine was maximal in both brain regions 2 hr after acute cocaine challenge. After 14 days of cocaine infusion, cocaine challenge in both strains reduced [³H]dopamine release in the nucleus accumbens, but not in the striatum; the reduction being greater in Wistar-Kyoto rats. The behavioral tolerance which accompanies similar cocaine infusion regimens may be related to striatal tolerance to cocaine-induced dopamine release.