蕨盲蝽属二新种(半翅目,盲蝽科)

记述蕨盲蝽属2新种:宽蕨盲蝽Bryocoris(Cobalorrhynchus)latus sp.nov.和亮蕨盲蝽Bryocoris(Bryocoris)nitidus sp.nov..模式标本存放于南开大学昆虫标本室. 新种与宽垫盲蝽族内的淡足息盲蝽Sinevia pallidipes (Zheng et Liu,1992)(胡奇,郑乐怡,2003)也相象,但新种爪内面无宽扁的爪垫而与蕨盲蝽族种类爪的类型相同,并且生殖腔腹向开口,可与之区别.     

模尖蛾属新种记述(鳞翅目:尖蛾科)

记述中国模尖蛾属Meleonoma Meyrick三新种：毛模尖蛾Meleomoma polychaeta,sp．nov,叶模尖蛾Meleonoma foliata,sp．nov．及刺模尖蛾Meleonoma echinata,sp．nov．。提供了成虫和雌雄外生殖器特征图。模式标本保存在南开大学生物系标本室。     

树干径流过程的动态响应模型

本文用实验测试法测量了干流过程。结果表明,干流过程曲线与R-L-C电路瞬态响应过程(包括输入、输出曲线)极为相似。据此,可用R-L-C电路瞬态响应过程曲线拟合干流过程,求出解析解。在计算机上调试参数,讨论其水文学意义,定性分析参数与影响干流因子的关系,取得了满意的结果。     

Formation of heterophile antibodies by human tonsilar lymphocytes: II. In vitro stimulation with allogeneic cells

Short-term cultures of human tonsilar lymphocytes (HTL), 5 × 10⁶ cells/culture, in medium RPMI 1640 supplemented with human group AB serum were studied for the production of plaque-forming cells (PFC) against sheep (SRBC) and bovine (BRBC) red blood cells following in vitro stimulation by various allogeneic lymphoid cells. Of 55 HTL specimens examined, 48 produced a significant number (50–300/culture) of PFC against SRBC and/or BRBC following the in vitro stimulation. The optimal doses of the stimulator HTL and peripheral blood lymphocytes (PBL) were 10⁷ and 5 × 10⁶/culture, respectively. After the stimulation, PFC appeared in significant numbers on the third day, reached the peak number on the sixth day, and decreased sharply in number thereafter. Removal of E-rosetting cells from both stimulator and responder populations abolished the PFC formation. PFC formation against SRBC was inhibited by solubilized Forssman antigen, while PFC formation against BRBC was inhibited strongly by Hanganutziu-Deicher antigen, hardly by Paul-Bunnell antigen and not at all by Forssman antigen. Supernatants of mixed lymphocyte culture of PBL were shown to enhance PFC formation of HTL cultures stimulated by allogeneic lymphocytes. The results of this study indicated that in vivo primed B cells of the HTL were triggered in vitro by allogeneic stimulation for the heterophile antibody formation. Since these antibodies are apparently directed against Forssman and Hanganutziu-Deicher antigens, the “allo” nature of these antigens as well as their relationship to the previously described heterophile transplantation antigens have to be clarified.     

DNA and protein content of mouse sperm: Implications regarding sperm chromatin structure

A variety of biochemical and histochemical techniques have been used to compare the composition of chromatin in sperm nuclei isolated from the epididymides of five mouse strains. The DNA content was determined by phosphorus analysis, deoxyribose analysis, absorption spectroscopy at 260 nm, and cytomorphometry following gallocyanine chrome alum staining. All four methods indicate that the mouse sperm nucleus contains approx. 3.3 pg DNA and that the DNA content does not vary significantly among the strains tested. Three different techniques, quantitative amino acid analysis, absorption spectroscopy at 230 nm, and sperm head density analysis in cesium chloride, were used to determine the protein content. Sperm nuclei from each strain of mouse were found to have a protein to DNA ratio of 0.9 and a chromatin protein content of 3 pg/nucleus. Comparisons of the basic proteins by disc gel electrophoresis demonstrate that the sperm nuclei contain only protamine and lack significant levels of somatic histones or transition proteins. The sperm from each strain contained both mouse protamine variants and the relative distribution of the two proteins did not appear to differ among strains. Using this information, we have been able to draw certain conclusions regarding DNA-protamine interactions and the mode of DNA packaging in the sperm nucleus. The most important of these is that the DNA in the mouse sperm nucleus cannot be packaged in nucleosomes. The protamines in sperm chromatin do not function as structural proteins, providing a subunit core around which the DNA is wrapped, but appear to completely neutralize the phosphodiester backbone of the DNA molecule, thereby minimizing the repulsion between neighboring segments of DNA and allowing it to be condensed into a biochemically inactive particle of genetic information.     

Spatially Distinct Pools of TORC1 Balance Protein Homeostasis

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Impact of the Arundo scale Rhizaspidiotus donacis (Hemiptera: Diaspididae) on the weight of Arundo donax (Poaceae: Arundinoideae) rhizomes in Languedoc southern France and Mediterranean Spain

Arundo donax L. (Poaceae) is native to Mediterranean Europe and invasive in the Rio Grande Basin of North America. Rhizomes from nine sites in France and Spain infested with a candidate control agent, the armoured scale Rhizaspidiotus donacis (Hemiptera: Diaspididae) weighed 50% less than those from nine sites without scale.     

Isolation and characterisation of transposon-induced mutants of Erwinia carotovora subsp. atroseptica exhibiting reduced virulence

Summary The blackleg pathogen Erwinia carotovora subsp. atroseptica (Eca) causes an economically important disease of potatoes. We selected a genetically amenable Eca strain for the genetic analysis of virulence. Tn5 mutagenesis was used to generate nine mutants which exhibited reduced virulence (Rvi^-) of strain SCRI1043. Following physiological characterisation, mutants were divided into three classes: (1) auxotrophs; (2) extracellular enzyme mutants; and (3) a growth rate mutant. The isolation of these Rvi^- mutants has allowed us to consider some factors that affect Eca virulence.     

Complete maps of IS1, IS2, IS3, IS4, IS5, IS30 and IS150 locations in Escherichia coli K12

Summary In this paper complete distribution maps are presented of the seven IS elements 1, 2, 3, 4, 5, 30 and 150. These maps were obtained during the construction of an almost complete restriction map of the Escherichia coli genome of K12 strain BHB2600. The positions of IS elements were correlated to this map. The distribution of integration sites of all IS types is nonrandom. Besides a large gap from 79 min to 96 min, there is a pronounced IS cluster at 6 min and another at 97 min, map locations that have low gene incidences on the classical map. One cluster coincides with a region of IS induced rearrangements. The IS distribution pattern was compared to patterns of strains W3110 and HB101.