人兽共患病原菌－猪链球菌2型的发病特点与防治对策

猪链球菌病是我国规定的二类动物传染病，其2型菌对人和猪均有很强的致病性，对公共卫生安全构成威胁。结合国内外10多年来对猪链球菌2型的病原特点、流行病学、临床症状和毒力因子的相关研究情况，总结了猪链球菌2型的发病特点，提出了针对该病的防治对策，为有效预防和控制人兽共患病的发生提供参考意见。     

杂交油菜宝油85特征特性及制种技术研究

宝油85是贵州省油菜研究所选育的杂交油菜新品种,于2007年11月通过国家下游区试审定[1].该品种生育期适中、产量高、品质好、抗耐病性较强,尤以高含油量突出,适合长江流域及与之生态条件相近的地区种植.     

In Vitro Development of Marmoset Monkey Oocytes by Pre-antral Follicle Culture

A technique for in vitro maturation of oocytes from small ovarian follicles of marmoset monkeys (Callithrix jacchus) has been developed. We employed a two‐step culture system for primary follicles (45–85 μm) and a one‐step culture technique for secondary follicles (>85 μm). The two‐step technique started with the culture of stromal tissue fragments for 2 days. Thereafter, mechanically isolated follicles were transferred to a culture system where they attached to the culture surface and grew for up to a further 12 days. Significant growth of the small follicles and their oocytes was only achieved with gonadotrophins in the medium. Oocytes with a mean diameter of 39 μm from follicles <85 μm reached a mean diameter of 90 μm by the end of the two‐step culture. After in vitro maturation, 19% of oocytes from these follicles had progressed to the germinal vesicle breakdown (GVBD). Follicles between 85 and 170 μm in diameter were isolated from the stroma and placed directly in the culture. Oocytes from these follicles had a mean diameter of 64 μm. The maximum size the oocytes reached in culture was related to the age of the females (pre‐pubertal females: 102 ± 1.3 μm; adults: 96 ± 1.4 μm). Twenty‐seven per cent of oocytes from pre‐pubertal ovaries achieved GVBD and nearly two‐thirds of these progressed to polar body stage. From adult ovaries, only 12% progressed to GVBD and one‐third of these to polar body stage. It is possible to develop mature oocytes in vitro from marmoset secondary pre‐antral follicles (>85 μm). From primary follicles, although near full size oocytes were developed, maturation capacity was incomplete.     

Fungal infection of the eyes of the snake Epicrates chenchria maurus: enucleation under halothane narcosis

In a rainbow boa (Epicrates chenchria maurus) an affection of the spectacle of the eyes caused by the fungus Fusarium oxysporum is described for the first time. Enucleation was performed under premedication of Hypnodil and inhalation anesthesia with tracheal intubation, using Halothane. Résumé. On décrit, pour la première fois, chez le boa Epicrates chenchria maurus une affection des paupières transparentes causée par le fongus Fusarium oxysparum. L'énucléation a été faite sous prémédication d'Hypnodil et d'inhalation anesthésie avec intubation trachéale, utilisant Halothane. Zusammenfassung. In einer Boa, Epicrates chenchria maurus, wurde eine Erkrankung von der durchsichtigen Kapsel über dem Auge, verursacht durch den Fungus Fusarium oxysporum zum ersten Ma1 beschrieben. Enukleation wurde vorgenommen, unter Basisnarkose van Hypnodil und Einatmungsanästhesie mit trachealer Intubation, indem man Halothane gebrauchte.     

喹烯酮合成方法的改进

改进了专利报道的喹烯酮合成方法.改进后的方法使用廉价易得的反应原料、催化剂及溶剂,采用一步反应合成喹烯酮的生产工艺,产品经红外光谱、氢核磁共振及质谱等分析,与对照品一致.     

Increased density and spatial uniformity increase weed suppression by spring wheat

It has been hypothesized that increased crop density and spatial uniformity can increase weed suppression and thereby play a role in weed management. Field experiments were performed over 2 years to investigate the effects of the density and spatial arrangement of spring wheat (Triticum aestivum) on weed biomass and wheat yield in weed-infested fields. We used three crop spatial patterns (normal rows, random and uniform) and three densities (204, 449 and 721 seeds m⁻²), plus a fourth density (1000 seeds m⁻²) in the random pattern. Increased crop density reduced weed biomass in all three patterns. Weed biomass was lower and crop biomass higher in wheat sown in the random and uniform patterns than in normal rows in both years. At 449 seeds m⁻², weed biomass was 38% lower in the uniform and 27% lower in the random pattern than in rows. There was evidence of decreasing grain yield due to intraspecific competition only at 1000 seeds m⁻². The results not only confirm that increasing density and increasing crop spatial uniformity increase the suppression of weeds, but also suggest that a very high degree of spatial uniformity may not be necessary to achieve a major increase in weed suppression by cereal crops. Rows represent a very high degree of spatial aggregation. Decreasing this aggregation increased weed suppression almost as much as sowing the crop in a highly uniform spatial pattern. While the random pattern produced as much crop biomass and suppressed weeds almost as well as the uniform pattern, the uniform pattern gave the highest yield.     

Response of Russet Burbank potatoes to soil fumigation and nitrogen fertilizers

Two field studies were conducted to determine the effects of soil fumigation on the response of Russet Burbank potatoes (Solanum tuberosum L.) to NH₄-N or NH₄NO₃ fertilizers. In one study fumigation increased yields but N source had no effect. In the other study fumigation had no effect but NH₄-N provided higher yields than NH₄NO₃. Microbial studies indicated that although populations of nitrifying bacteria were initially altered by fumigation, nitrification rates were similar to those in non-fumigated soil. In a controlled environment study in which potatoes were grown in fumigated field soil, neither N source nor fumigation had any effect on growth or yield. These studies indicated that fumigation had no effect on the response of potatoes to NH₄-N or NH₄NO₃ fertilizers.