辽宁省西部棘蝇属一新种：双翅目：蝇科

本文记述于辽宁朝阳市采到的棘蝇属１新种：辽西棘蝇Ｐｈａｏｎｉａｌｉａｏｓｈｉｅｎｓｉｓ ｓｐ．ｎｏｖ。模式标本存辽宁朝阳市卫生防疫站。     

中国脊翅叶蝉属种类记述（同翅目：叶蝉科）

本文记述４种中国脊翅叶蝉,其中包括１新种──杨氏脊翅叶蝉Ｐａｒａｂｏｌｏｐｏｎａｙａｎｇｉｓｐ．ｎ．,并报道了其中２个已知种的新分布地。文中还列有分种检索表。新种模式标本存西北农业大学昆虫博物馆。     

玉米根冠细胞的脱落及其对根与根际关系的影响

以光学与电子显微镜技术观察了玉米幼苗根冠细胞脱落进程与胞间关系的变化。发现随着外沿细胞的脱离,固有的胞间连丝渐次伸展、孔径扩展,进而断裂为半连丝。半连丝内侧端仍与质膜保持固有的连接;外侧端向壁外伸展,直接与根际介质沟通,从而在根冠共质体与根际质外体之间建立了动态性的单向共质联系。以成列囊泡在半连丝中存在与由断口端溢出、半连丝呈现活跃ＡＴＰ酶活性、外源不透膜示踪物向胞内原生质掺入以及原生质的穿壁等实例证明,半连丝仍具生理活性,可作为根冠共质体与根际介质间物质与信息交流的直接通道。     

条锈菌侵染初期小麦初生叶内可翻译mRNA的变化

小麦条锈菌毒性小种及其无毒性突变型侵染初期,是不亲和反应的小麦叶片内可翻译ｍＲＮＡ水平迅速增加,而呈亲和反应叶片的增加幅度小且滞后。同时前者的Ｐｏｌｙ（Ａ＋）－ＲＮＡ水平高于未接种对照,后者低于对照。３２Ｐ标记实验证实不亲和反应叶片Ｐｏｌｙ（Ａ＋）－ＲＮＡ的合成增加早于亲和反应叶片。Ｐｏｌｙ（Ａ＋）－ＲＮＡ体外翻译产物经ＳＤＳ－ＰＡＧＥ分离后,放射自显影图谱显示一些多肽条带的３５Ｓ－Ｍｅｔ相对掺入量有定量差异。     

缺磷或缺铁引起白羽扇豆锰中毒的机理

白羽扇豆在缺磷或缺铁条件下均有排根形成,并且根系还原力显著增加。缺磷、缺铁根系还原力在高峰期分别高于对照。缺磷与缺铁根系还原力高峰不仅出现的时期不同,而且还原力增加部位也不一样。缺磷处理的排根区具有很高的还原力,缺铁处理还原力较高的部位是在主根和侧根的根尖以及排根区。由于Ｍｎ４＋比Ｆｅ３＋更易被还原,致使根系还原力提高促使根际大量锰被还原,这是缺磷和缺铁造成白羽扇豆锰中毒的主要原因之一。     

中药玄参的化学成分

从中药玄参（ＳｃｒｏｐｈｕｌａｒｉａｎｉｎｇｐｏｅｎｓｉｓＨｅｍｓｌ．）中分离得到１个新化合物：４－Ｏ－（对甲氧基肉桂酰基）－α－Ｌ－鼠李糖［４－Ｏ－（ｐ－ｍｅｔｈｏｘｙｃｉｎｎａｍｏｙｌ）－α－Ｌ－ｒｈａｍｎｏｐｙｒａｎｏｓｅ］;同时还分离到４个已知的环烯醚萜甙：爪钧草甙（ｈａｒｐａｇｉｄｅ）,爪钩草酯甙（ｈａｒｐａｇｏｓｉｄｅ）,Ｏ－甲基梓醇（Ｏ－ｍｅｔｈｙｌｃａｔａｌｐｏｌ）,士可玄参甙Ａ（ｓｃｒｏｐｏｌｉｏｓｉｄｅＡ）和１个已知的苯丙素甙：安格洛甙Ｃ（ａｎｇｏｒｏｓｉｄｅＣ）。新化合物的结构通过化学降解和光谱分析得到证明。     

家鸽、黄雀和黄喉鹀耳蜗核的定位与比较

向非鸣禽家鸽（Ｃｏｌｕｍｂａ ｌｉｖｉａ ｄｏｍｅｓｔｉｃｕｓ）和鸣禽黄雀（Ｃａｒｄｕｅｌｉｓ ｓｐｉｎｕｓ）、黄喉鹀（Ｅｍｂｅｒｉｚａ, ｅｌｅｇａｎｓ）耳蜗内注射 ＨＲＰ作顺行追踪表明,耳蜗纤维组成第八脑神经的听支（ Ｎ Ⅷ）后,分别投射至延髓的角状核（ＮＡ）和巨细胞核（ＮＭ）,由 ＮＡ及 ＮＭ两个亚核组成耳蜗核（ｎｕｃｌｅｕｓ ｃｏｃｈｌｅａ）,它是听觉的上行通路中的第一级中继站,延髓层状核并不接受耳蜗纤维的直接投射。家鸽与黄雀、黄喉鹀之间的ＮＡ、ＮＭ及ＮⅧ在形态和分布上都有较明显的差别。     

精子介导鱼类基因转移和聚合酶链反应检测技术

金鱼精子与美洲大绵ｗｅｉ的抗冻蛋白基因一起保温３０分钟后,再与卵子受精,共获得１４５尾成鱼和若干胚胎。从胚胎和成鱼中提取ＤＮＡ经聚合酶链反应（ＰＣＲ法）扩增和Ｓｏｕｔｈｅｒｎ ｂｌｏｔ分子杂交表明,外源的抗冻蛋白基因进入了部分受体鱼的染色体组内。测定了４５尾一年龄实验鱼中,有１２尾显示出明确的杂交带,阳性率为２６％。     

排卵,排精前后文昌鱼体内GnRH的研究

利用放射免疫分析法测定了排卵、排精前后青岛文昌鱼体内促性腺激素释放激素（ＧｎＲＨ）的含量变化,并通过高效液相色谱比较了雌、雄文昌鱼性腺及除性腺外体部ＧｎＲＨ的种类和含量的异同。结果表明：１）生殖过程中雌、雄文昌鱼体内ＧｎＲＨ含量的变化规律不同;雌性文昌鱼体内ＧｎＲＨ总含量在排卵时有所下降,排后１２小时政策最为明显,以后逐渐上升到排前水平;雄性文昌鱼仅在排精时有所下降,２小时后即稳定在排水平。２）文     

Nuclear replication activities during imbibition of abscisic acid- and gibberellin-deficient tomato (Lycopersicon esculentum Mill.) seeds

The role of cis-abscisic acid (ABA) and gibberellins (GAs) in the induction of cell-cycle activities has been studied during imbibition and subsequent germination of tomato seeds. Using flow cytometry, nuclear replication activity was investigated in embryo root tips isolated from seeds of the ABA-deficient mutant sit ^w , the GA-deficient mutant gib-1, and the wild-type (MM) tomato (Lycopersicon esculentum Mill. cv. Moneymaker) upon imbibition in water, 10 μM GA₄₊₇, 5 μM ABA or 5 μM ABA+10 μM GA₄₊₇. The nuclei of fully matured dry MM, sit ^w and gib-1 seeds predominantly showed 2C DNA signals, indicating that the cell-cycle activity of most root-tip cells had been arrested at the G₁ phase of nuclear division. However, ABA-deficient sit ^w seeds contained a significantly higher amount of G₂ cells (4C DNA) compared with the other genotypes, suggesting that, during maturation, cell-cycle activity in sit ^w seeds is less efficiently arrested in G₁. Upon imbibition in water, an induction of the 4C signal, indicating nuclear replication, was observed in the root tip cells of both MM and sit ^w embroys. The augmentation in the 4C signal occurred before visible germination. Gib-1 seeds did not show cell-cycle activity and did not germinate in water. Upon imbibition in GA₄₊₇, both cell-cycle activity and subsequent germination were enhanced in MM and sit ^w seeds, and were induced in gib-1. In ABA, the germination of MM and sit ^w seeds was inhibited while nuclear replication of these seeds was not affected. It is concluded that GA influences germination by acting upon processes that precede cell-cycle activation, while ABA affects growth by acting upon processes that follow cell-cycle activation.