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61.
利用激光微束穿刺法将外源基因导入小麦的研究 总被引:21,自引:1,他引:20
用激光微束穿刺法将携带有新霉素磷酸转移酶(NPT-Ⅱ)基因的质粒pJIT101导入京花1号小麦幼胚细胞。方法是将小麦幼胚细胞进行高渗缓冲液预处理,用微米级的激光微束处理,然后在卡那霉素培养基上筛选出具抗性的愈伤组织及绿色小植株。第一年,从150个小麦幼胚中,在卡那霉素培养基上筛选出4株绿苗,取两株进行NPT-Ⅱ酶活性分析,测到了NPT-Ⅱ酶的活性。第二年重复实验,从245个小麦幼胚中,经筛选获得1株绿苗,进行了叶片DNAPCR扩增检测,转化的绿色小苗扩增出所导入的NPT-Ⅱ基因编码的片段。结果表明,外源NPT-Ⅱ基因已导入了小麦,并实现了整合表达。 相似文献
62.
记述采自我国云南省勐腊的盖蛛属1新纪录种-鹤嘴盖蛛Nerienemacella(Thorell.1898)。 相似文献
63.
By means of an in vivo brain microdialysis, the effect of different concentrations of physostigmine on the acetylcholine level in the dialysate of rat frontal cortex was studied. Perfusion of the various degrees of physostigmine (eserine) concentration (10 nM−10 μM) into the cortex through the dialysis membrane increased the basal acetylcholine level in a dose-dependent manner. In the presence of 10 nM, 0.1 μM and 10 μM physostigmine in the perfusate, systemic treatment with scopolamine (0.5 mg/kg, i.p.) increased 200, 270 and 510%, respectively, the relative acetylcholine level in the dialysates in comparison with the corresponding basal levels, while in the absence of physostigmine the treatment increased it only 40%. From these results, it appears that perfusion of physostigmine at a variety of concentrations, changes not only the basal level of acetylcholine induced by the inhibition of acetylcholinesterase but also the relative acetylcholine output induced by systemic treatment with scopolamine. 相似文献
64.
MethodsforHandy,RapidIsolationofHighQualityRNAbyGuanadiumThioeyauateDuJianYuanYanhuaMaShenglinDongZhiwei(BeijingInstituteforCancerResearchBeijing100034)硫氰胍是一种有效的蛋白变性剂。早在1979年,Chirgwin等就利用氯化铯/硫氰胍超离心技术成功地从RNA酶富集的胰脏组织中提取出未降解的RNA分子[2],从而使它成为抑制RNA酶的首选药物并得到广泛使用,但受到超速离心设备的限制。1983年,Cathala报道了氯化锂/硫氰胍RNA提取法[1]。该方法操作简便,获得的RNA质量很高,但所需时间较长。为了能在短时间内更快… 相似文献
65.
Chronic Nicotine Administration Differentially Affects Neurotransmitter Release from Rat Striatal Slices 总被引:6,自引:3,他引:3
Abstract: The objective of these experiments was to determine whether the chronic administration of nicotine, at a dose regimen that increases the density of nicotine binding sites, alters the nicotine-induced release of [3H]dopamine ([3H]DA), [3H]norepinephrine ([3H]NE), [3H]serotonin ([3H]5-HT), or [3H]acetylcholine ([3H]ACh) from rat striatal slices. For these experiments, rats received subcutaneous injections of either saline or nicotine bitartrate [1.76 mg (3.6 µmol)/kg, dissolved in saline] twice daily for 10 days, and neurotransmitter release was measured following preloading of the tissues with [3H]DA, [3H]NE, [3H]5-HT, or [3H]choline. Chronic nicotine administration did not affect the accumulation of tritium by striatal slices, the basal release of radioactivity, or the 25 mM KCl-evoked release of neurotransmitter. Superfusion of striatal slices with 1, 10, and 100 µM nicotine increased [3H]DA release in a concentration-dependent manner, and release from slices from nicotine-injected animals was significantly (p < 0.05) greater than release from saline-injected controls; release from the former increased to 132, 191, and 172% of release from the controls following superfusion with 1, 10, and 100 µM nicotine, respectively. Similarly, [3H]5-HT release increased in a concentration-related manner following superfusion with nicotine, and release from slices from nicotine-injected rats was significantly (p < 0.05) greater than that from controls. [3H]5-HT release from slices from nicotine-injected rats evoked by superfusion with 1 and 10 µM nicotine increased to 453 and 217%, respectively, of release from slices from saline-injected animals. The nicotine-induced release of [3H]NE from striatal slices was also concentration dependent but was unaffected by chronic nicotine administration. [3H]ACh release from striatal slices could not be detected when samples were superfused with nicotine but was measurable when tissues were incubated with nicotine. The release of [3H]ACh from slices from nicotine-injected rats was significantly (p < 0.05) less than release from controls and decreased to 36, 83, and 77% of control values following incubation with 1, 10, or 100 µM nicotine, respectively. This decreased [3H]ACh release could not be attributed to methodological differences because slices from nicotine-injected rats incubated with nicotine exhibited an increased [3H]DA release, similar to results from superfusion studies. In addition, it is unlikely that the decreased release of [3H]ACh from striatal slices from nicotine-injected rats was secondary to increased DA release because [3H]ACh release from slices from hippocampus, which is not tonically inhibited by DA, also decreased significantly (p < 0.05) in response to nicotine; hippocampal slices from nicotine-injected rats incubated with 1 and 10 µM nicotine decreased to 42 and 70%, respectively, of release from slices from saline-injected animals. Results indicate that the chronic administration of nicotine increases the ability of nicotine to induce the release of [3H]DA and [3H]5-HT and decreases the ability of nicotine to evoke the release of [3H]ACh but does not alter the nicotine-induced release of [3H]NE from brain slices. 相似文献
66.
三褶脉紫菀中的新二萜甙 总被引:1,自引:0,他引:1
三褶脉紫菀(AsterageratoidesTurcz.)系菊科多年生草本植物,遍布全国,是民间常用的中药,有清热解毒、祛痰镇咳的功效[1,2]。化学工作者们曾从其同属植物紫菀(AstertararicusL.f.)中分离到紫菀酮(shionone)、槲皮素(quercetin)、无羁萜(friedelin)、表无羁萜(epifriedelinel)、毛叶醇(lachnophyllol)、乙酸毛叶酯(lachnophyllolacetate)、茴香醚(anethole)以及紫菀三萜皂甙[2—4]… 相似文献
67.
芦苇耐盐变异植株及其细胞学鉴定 总被引:5,自引:0,他引:5
用甲基磺酸乙酯(EMS)处理芦苇(Phragm itescom m unis Trin.)胚性愈伤组织。从处理后的愈伤组织诱导获得芦苇耐盐变异植株R5002-12。变异植株能在含有1% NaCl的MS培养基上生长。细胞学检查变异植株是混倍体,染色体数目变异范围在100至33 之间。分蘖植株具有相似的形态学及染色体变异特性 相似文献
68.
几种濒危植物及其近缘类群总DNA的提取与鉴定 总被引:122,自引:0,他引:122
用低pH 介质,高盐沉淀蛋白质方法成功地从银杉(Cathaya argyrophylla Chun etKuang)、矮牡丹(Paeonia suffruticosa var. spontanea)、南川升麻(Cim icifuga nanchuanensisHsiao)、裂叶沙参(Adenophora lobophylla)的同属种泡沙参(A. potaninii)等植物中提取和部分纯化了细胞总DNA,并对其产率、质量和纯度作了鉴定。此方法的关键是用了一个低pH提取介质,它能有效防止组织破碎及沉淀大量材料时的电离化作用及酚化合物的进一步氧化。所得DNA 不需经氯化铯梯度离心或柱层析,直接可用于限制性片断长度多态性(RFLP)及随机扩增的DNA多态性(RAPD)等分子水平的遗传标记。为检测濒危植物的遗传多样性提供了一套迅速、简便和可靠的技术方案 相似文献
69.
大萼香茶菜辛素的化学结构 总被引:3,自引:0,他引:3
大萼香茶菜(Rabdosiamacrocalyx(Dunn)Hara)系唇形科(Labiatae)香茶菜属植物,民间用于治疗肿瘤等疾病。我们曾报道了它的具有抗菌和细胞毒活性的7个新二萜成分:大萼香茶菜甲素、乙素、丙素、丁素、戊素、己素和庚素[1—5]。进一步研究又分得3个结晶单体。其中,结晶Ⅰ鉴定为新化合物,命名为大萼香茶菜辛素;结晶Ⅱ和Ⅲ鉴定为已知化合物oridonin和enmenol。大萼香茶菜辛素(Ⅰ) C22H34O8,mp230℃,[α]22D-41.8(c0.22,MeOH)。IR不… 相似文献
70.