二核苷酸重复多态性的非同位素检测及其在基因诊断中的应用

本文报道了一种检测二核苷酸重复多态性的简便的非同位素法,利用重复序列两侧的特异引物进行ＰＣＲ扩增,产生的等位片段在薄层变性聚丙烯酰胺凝胶电泳上分离,再用灵敏的银染法显色。该方法不需要标记ＰＣＲ产物,简便、快速,分辨率可达１ｂｐ,并可用多对引物同时进行多重ＰＣＲ分析。用此方法对ＤＭＤ家系成员ｄｙｓｔｒｏｐｈｉｎ基因的５＇－脑型外显子止游区和３＇－非翻译区的两个（ＣＡ）。位点进行了扩增片段长度多态性分     

不同施肥杨树主要营养元素内外循环比较研究 Ⅱ．施肥对落叶前后杨树叶片营养元素浓度及贮量的影响

杨树叶片在凋落前将大量有机质输入干、枝、根中,在不同处理中,不施肥输出的比例大于施肥．施Ｐ并不导致杨树对Ｐ的奢侈吸收．施肥可使杨树主要营养元素的外循环通量高于不施肥．不施肥杨树叶片在凋落前Ｐ、Ｋ的输出率比施肥高约１０％．     

我国某些苏铁类生殖器官化石的发现兼论苏铁类起源

本文对苏铁类化石的系统分类作了概要的介绍。重点报道了笔者在近廿年来所采集的苏铁类生殖器官化石,特别是中晚石炭世的一枚苏铁大孢子叶化石的发现,将苏铁类起源的时间大大地推前了,并指出其起源地应在中国西北的甘肃地区。所有这些生殖器官的发现将推动苏铁化石生殖生物学的发展,对其起源、分布、演化和苏铁植物区系的形成和发展提供了极为重要的材料。     

中国紫金牛属一新种

中国紫金牛属一新种胡启明（中国科学院华南植物研究所,广州５１０６５０）关键词紫金牛属;光萼紫金牛;新种ＡＮＥＷＳＰＥＣＩＥＳＯＦＡＲＤＩＳＩＡＦＲＯＭＣＨＩＮＡ￥ＨｕＣｈｉｍｉｎｇ（ＳｏｕｔｈＣｈｉｎａＩｎｓｔｉｔｕｔｅｏｆＢｏｔａｎｙ,Ａｃａｄｅｍ...     

无花果蛋白酶在阴离子交换树脂上的固定化

无花果蛋白酶通过８％戊二醛活化载体,共价结合到聚苯乙烯阴离子交换树脂ＧＭ２０１上,固定化作用在ｐＨ７．７,酶浓度０．８ｍｇ／ｇ树脂,４℃下进行６ｈ。得到的固定化酶表观Ｋ_ｍ值（酪蛋白,１．１１×１０~（－４）ｍｏｌ／Ｌ）小于溶液酶Ｋ_ｍ值（１．９６×１０~（－４）ｍｏｌ／Ｌ）;固定化酶活性在ｐＨ６～８保持稳定,溶液酶最适ｐＨ为７．２;固定化酶最适温度由溶液酶的５０～６０℃移至３７℃;固定化酶２５℃保持７ｄ,重复水解酪蛋白７次后,保留８３．３％活性。固定化酶对酪蛋白水解度达４７．５％,对大豆球蛋白达１１．６％。     

昆虫杆状病毒晚期启动子在大肠杆菌中启动CAT基因表达

将油桐尺蠖（Ｂｕｚｕｒａｓｕｐｐｒｅｓｓａｒｉａ）核多角体病毒晚期基因──多角体蛋白基因启动子及５′端编码区,以两种不同方式置于缺乏启动子的氯霉素乙酰基转移酶（ＣＡＴ）基因上游,使其分别终止在不同翻译终止位点,其宿主菌具有明显不同的氯霉素抗性,最高达２００ｍｇ／Ｌ　ＬＢ培养基以上,表明昆虫病毒启动子能启动原核基因表达。对多角体蛋白基因启动子能在大肠杆菌中有效工作的原因进行了讨论。     

Evidence that 5-HT2 antagonism elicits a 5-HT3-mediated increase in dopamine transmission

Amperozide, a novel atypical antipsychotic drug with few extrapyramidal side effects, is a strong serotonin₂ (5-HT₂) antagonist but has low affinity for dopamine receptors in vitro. The effect of amperozide on the dopaminergic synapse was studied with an in vivo microdialysis technique using anesthetized male Sprague-Dawley rats. Following implantation of dialysis probes into the striatum and nucleus accumbens (NuAc), amperozide was intravenously infused as six consecutive incremental doses (0.5, 0.5, 1.0, 2.0, 4.0 and 8.0 mg/kg) at intervals of 15 min. From the beginning of drug infusion, perfusates were collected in fractions every 30 min throughout a total period of 120 min. The samples were then immediately analyzed by high-performance liquid chromatography with electrochemical detection. Amperozide induced a dose-related elevation of dopamine, 3,4-dihydroxyphenylacetic acid (DOPAC) and 5-hydroxyindolacetic acid (5-HIAA) levels in both areas.p-Chlorophenylalanine (pCPA) pretreatment abolished the production of 5-HIAA in both areas and attenuated the amperozide-induced rise of DOPAC but not of dopamine. After pretreatment with an intravenous 5-HT₃ antagonist, MDL 72222, the amperozide-induced changes in dopamine, DOPAC and 5-HIAA in both areas were lower than in the saline control group. Preliminary data showed that afterpCPA pretreatment, incremental concentrations of the 5-HT₃ agonist 1-(m-chlorophenyl)-biguanide perfused via the probe also produced significant elevation of dopamine and DOPAC levels in these two areas. Taken together, these results suggest that amperozide may directly block 5-HT₂ receptors in the striatum and NuAc, thereby enhancing 5-HT transmission. The enhanced 5-HT transmission may activate postsynpatic 5-HT₃ receptors located on the dopaminergic terminals, leading to changes in dopamine transmission in these two areas.     

Isolated microspore culture of wheat (Triticum aestivum L.) in a defined media I. Effects of pretreatment,isolation methods,and hormones

Significant improvements were achieved in the production of haploid and doubled haploid plants from isolated microspore culture of wheat c.v. Chris on a defined media. Procedures found to be of benefit included: A 7-day pretreatment of anthers in 0.4M mannitol plus the macronutrients from FHG medium; the inclusion of 4.5 mg/liter abscisic acid in the pretreatment solution; the isolation of microspores from pretreated anthers by vortexing; and the use of phenylacetic acid (PAA) as the auxin source in MS medium. The best response was achieved with 4.0 mg/liter PAA in MS medium containing 90 g/liter maltose as the sugar source. Under these conditions, 68% of viable microspores underwent division, and an average of 93 embryos and 92 green plants were regenerated per 100 anthers used. The root-tip chromosome number and the fertility of 114 regenerating green plants revealed that 75% were completely fertile spontaneously doubled haploids.     

新疆六个民族指纹白线的调查研究The hand Print of Six Nationalities in Xinjiang

本文首次报道了新家6各民族6134人（南3181人、女2953人）的指纹白线出现频率。结果表明,白线频率女高于男,民族间亦有差异,其中维吾尔、哈萨克、鸟孜别克族频率接近。塔吉克族居住高寒高原地区,属白色人种,频率明显低于以上3个民族,锡伯族和汉族生活习惯近似,且高于以上4个民族,作者认为,白线出现频率的高低与种族、性别、年龄和群体生长环境及生活习惯有关。We’ve studied 6134 individuals (male 3181, fimale 2953) of six nationalities in Xinjiang.The result is that the white line of hand print is associated with rae,sex,age,grow environments of groups and life habbits.The ifference of races is:The appearant rates of white line of Weivuerite,Hasakese and Wuzibese are near,Tajike’s rate is lower than xiboman’s and han are higher than others.     

Suppression of albumin enhancer activity by H-ras and AP-1 in hepatocyte cell lines.

We demonstrated, using a transient transfection assay, that the albumin enhancer increased the expression of the albumin promoter in a highly differentiated, simian virus 40 (SV40)-immortalized hepatocyte cell line, CWSV1, but was not functional in two ras-transformed cell lines (NR3 and NR4) derived from CWSV1 by stable transfection with the T24ras oncogene. A transient cotransfection assay showed that T24ras and normal c-Ha-ras were each able to inhibit the activity of the albumin enhancer in an immortal hepatocyte cell line. DNase I footprinting and gel mobility shift assays demonstrated that the DNA binding activities specific to the albumin enhancer were not decreased in the ras-transformed cells. ras also did not diminish the expression of HNF1 alpha, C/EBP alpha, HNF3 alpha, HNF3 beta, or HNF3 gamma but did significantly increase AP-1 binding activity. Three AP-1 binding sites were identified within the albumin enhancer, and DNA binding activities specific to these AP-1 sites were induced in the ras-transformed hepatocytes. Subsequent functional assays showed that overexpression of c-jun and c-fos inhibited the activity of the albumin enhancer. Site-directed mutagenesis of the AP-1 binding sites in the albumin enhancer partially abrogated the suppressing effect of ras and c-jun/c-fos on the enhancer. These functional studies therefore supported the results of the structural studies with AP-1. We conclude that the activity of the albumin enhancer is subject to regulation by ras signaling pathways and that the effect of ras on the albumin enhancer activity may be mediated by AP-1.