N-(2-吡啶基)-N'-苯基脲对几种作物种子根、芽生长影响的回归分析

N-（2-吡啶基）-N'-苯基脲（2PU）,属苯基脲衍生物,具有细胞分裂素活性,有关其合成和应用的研究未见报道。作者合成了2PU并进行了生物效应试验研究。结果表明,2PU对作物种子萌发时胚根、胚芽的生长具有明显的促进作用,其根、芽生长与2PU浓度之间的关系符合Y=a＋bX＋eX2＋的数学模型。2PU对小麦根芽和赤豆根芽生长最佳浓度分别是0.001～0.0lppm、0.005～0.05ppm,对黄豆根生长以0.001～0.06ppm最佳。     

“增收宝－3”中氨基酸成分

用日立８３５－５０型氨基酸分析仪对“增收宝－３”中游离的氨基酸进行了分析。结果表明其中含有１５种氨基酸,以脯氨酸含量最高。实验结果揭示,氨基酸可能是“增收宝－３”中抗逆增产的有效成分。     

In vitro maturation of porcine oocytes in follicular fluid with subsequent effects on fertilization and embyo yield in vitro

The objective of the present study was to test the ability of porcine follicular fluid (pFF) to improve maturation of porcine cumulus-oocyte-complexes (COC) in vitro and to observe subsequent effects on fertilization and development to late morula/blastocyst stages under in vitro conditions. The COC were incubated in Tissue Culture Medium (TCM) 199, supplemented with 1% fetal calf serum (FCS), 10% pFF collected from immature follicles (2 to 5 mm), with or without addition of 1microg/ml FSH. Control groups were matured in TCM 199 with or without FSH. Follicular aspirates were centrifuged (1700 x g, 5min.) and the supematants were stored at -20 degrees in 1.5-ml Eppendorff cups until used. On 7 experimental days a total of 3849 immature COC was aspirated from follicles ranging from 2 to 5 mm in diameter. A total of 1117 COC was selected for the experiments, and 239 COC were fixed and stained with 1.5% aceto-orcein after 48 h of in vitro maturation at 39 degrees C with 5% CO(2) in humidified air. Germinal vesicle breakdown (GVBD; 91.7%) and development to metaphase II (60.4%) were superior (P 相似文献   

GI双突变体GIK253RA198C的构建及其性质分析

以双引物法对葡萄糖异构酶（GI）基因进行定点突变,将突变体基因于大肠杆菌中表达,获得了GI双点突变体GIK253RA198C.研究K253R和A198C双点突变对GI的结构和性质的作用,结果表明GIK253RA198C的热稳定性明显下降,最适反应温度降低5℃.文章从结构和机制上解释了为何同是K253R突变,对SM33 GI和密苏里游动放线菌GI的热稳定性产生不同的影响,认为这是由于Lys253在两种GI结构的位置上存在微小差异,从而使引入的Arg对亚基间的相互作用产生了相反效应所引起.     

The Mammalian Protein (rbet1) Homologous to Yeast Bet1p Is Primarily Associated with the Pre-Golgi Intermediate Compartment and Is Involved in Vesicular Transport from the Endoplasmic Reticulum to the Golgi Apparatus

Yeast Bet1p participates in vesicular transport from the endoplasmic reticulum to the Golgi apparatus and functions as a soluble N-ethylmaleimide–sensitive factor attachment protein receptor (SNARE) associated with ER-derived vesicles. A mammalian protein (rbet1) homologous to Bet1p was recently identified, and it was concluded that rbet1 is associated with the Golgi apparatus based on the subcellular localization of transiently expressed epitope-tagged rbet1. In the present study using rabbit antibodies raised against the cytoplasmic domain of rbet1, we found that the majority of rbet1 is not associated with the Golgi apparatus as marked by the Golgi mannosidase II in normal rat kidney cells. Rather, rbet1 is predominantly associated with vesicular spotty structures that concentrate in the peri-Golgi region but are also present throughout the cytoplasm. These structures colocalize with the KDEL receptor and ERGIC-53, which are known to be enriched in the intermediate compartment. When the Golgi apparatus is fragmented by nocodazole treatment, a significant portion of rbet1 is not colocalized with structures marked by Golgi mannosidase II or the KDEL receptor. Association of rbet1 in cytoplasmic spotty structures is apparently not altered by preincubation of cells at 15°C. However, upon warming up from 15 to 37°C, rbet1 concentrates into the peri-Golgi region. Furthermore, rbet1 colocalizes with vesicular stomatitis virus G-protein en route from the ER to the Golgi. Antibodies against rbet1 inhibit in vitro transport of G-protein from the ER to the Golgi apparatus in a dose-dependent manner. This inhibition can be neutralized by preincubation of antibodies with recombinant rbet1. EGTA is known to inhibit ER-Golgi transport at a stage after vesicle docking but before the actual fusion event. Antibodies against rbet1 inhibit ER-Golgi transport only when they are added before the EGTA-sensitive stage. These results suggest that rbet1 may be involved in the docking process of ER- derived vesicles with the cis-Golgi membrane.     

Physiologic regulation of mixtalol in rape senescence and its yield effects

Physiologic and yield effects of mixtalol at various concentrations sprayed on rape at the anthesis stage were examined. Foliar sprays of 4 and 2 ppm mixtalol significantly increased the chlorophyll content of rape leaves and pods, reduced the accumulation of malondialdehyde and ethylene production, and delayed the degradation of superoxide dismutase and catalase activities of the rape plant. Mixtalol also increased root oxidizability. Meanwhile, the number of branches and pods per plant was increased, and a 10.7% and 8.2% increase of seed yield over the controls was observed with treatments of 4 and 2 ppm mixtalol, respectively. No significant effects from mixtalol were observed on the maturation of plants or on the seed oil content or the erucic acid and glucosinolate content. Total rape oil production increased with 4 and 2 ppm mixtalol significantly by 12.4% and 10.5%, respectively, over the controls.Abbreviations MTL mixtalol - MDA malondialdehyde - TBA thiobarbituric acid - SOD Superoxide dismutase - CAT catalase - TTC tetrazolium     

南岭植物区系地理学研究──Ⅲ．植物区系地理亲缘与区划

南岭山地与相邻地区植物区系具有明显的过渡或替代关系,主要通过亚热带及亚热带亚热带亚洲分布成分与华南南亚热带及亚洲热带地区联系;与华中和华东地区植物区系的联系以亚热带及亚热带至温带分布和中国—日本间断分布成分来沟通;与西南地区植物区系的联系则表现为两地共有的古老和与遗成分区及石灰岩山地区系成分．华夏植物区系,是从古老的华夏植物群逐步发展起来的统一体,在区系分区上应划归为统一的华夏植物界,下分东亚植物区、马来西亚植物区和印度—喜马拉雅植物区。南岭山地植物区系拥有其自身的标志种、特有属和丰富的特有种,在区系分区上可划为完整的南岭植物亚省,下分东南岭植物县、中南岭植物县和西南岭植物县。     

培养乳鼠心肌细胞自发性〔Ca~（2＋）〕_i瞬间变化的实验模型

使用Ｃａ￣（２＋）敏感的荧光指示剂Ｆｕｒａ－２／ＡＭ,对培养的心肌细胞测定细胞内Ｃａ￣（２＋）的瞬间变化。结果为,在一个心搏周期中,经过大约１８０ｍｓ的时间,［Ｃａ￣（２＋）］＿ｉ瞬间变化达到最大值,然后恢复到基线水平（最小值）,经历了２６０ｍｓ。测得平均［Ｃａ￣（２＋）］＿ｉ瞬间变化的最大值及最小值分别为３４６±３８ｎｍｏｌ／Ｌ和１０２±１８ｎｍｏｌ／Ｌ。血管紧张素Ⅱ１００ｎｍｏｌ／Ｌ引起［Ｃａ￣（２＋）］＿ｉ瞬间变化最大值明显增加,但对［Ｃａ￣（２＋）］＿ｉ瞬间变化的基线水平没有明显的影响。ｒｙａｎｏｄｉｎｅ３μｍｏｌ／Ｌ使［Ｃａ￣（２＋）］＿ｉ瞬间变化的幅度明显降低。ＫＣｌ５０ｍｍｏｌ／Ｌ使［Ｃａ￣（２＋）］＿ｉ瞬间变化完全停止,并明显增加［ｃａ￣（２＋）］＿ｉ的基线水平。结果提示,本实验模型可用来观察［Ｃａ￣（２＋）］＿ｉ的瞬间变化。     

Effects of prostaglandin E2, 16,16-dimethyl prostaglandin E2 and a prostaglandin endoperoxide analogue (U-46619) on gastric secretory volume, [H] and mucus synthesis and secretion in the rat

The effects of orally administered prostaglandin E₂, 16,16-dimethyl prostaglandin E₂ and U-46619, an analogue of the prostaglandin endoperoxide PGH₂, on gastric secretory volume, acid and mucus were studied in the rat. All of the compounds significantly increased the volume of gastric secretion, mucus secretion, measured as N-acetylneuraminic acid and mucus synthesis measured as the incorporation of [³H]-glucosamine into mucosal glycoprotein; however, only PGE₂ and 16,16-dimethyl PGE₂ inhibited acid secretion. U-46619, 1.5 mg/kg provided significant protection against ethanol-induced gastric ulcers, an effect that has been previously shown for the other two compounds. These studies provide additional evidence that prostaglandin induced mucosal protection may by related to an effect on mucus and on stimulation of nonparietal cell gastric secretion. Further study of these parameters may be important in the development of antiulcer drugs for long term clinical use.