Recovery from a viral respiratory tract infection. IV. Specificity of protection by cytotoxic T lymphocytes

Immune spleen cells enhanced for influenza-specific cytotoxic activity after exposure to virus-infected stimulator cells in vitro effect recovery when transferred to nude and immunocompetent mice with influenza pneumonia (5). This protective effect correlated with the virus-specific cytotoxic activity of the transferred lymphocytes and is removed by treatment with anti-0 serum and complement. The experiments presented here indicate that spleen cells taken directly from mice undergoing a primary or secondary infection are less protective than immune spleen cells that are restimulated in vitro before transfer. This decreased ability to clear pulmonary virus and effect survival correlated with their relatively lower levels of influenza-specific cytotoxicity. Protection did not correlate with the level of natural killer cell activity of transferred cells. The results also indicate the immune spleen cells that are protective are influenza A subtype cross-reactive and are H-2-restricted; H-2d immune spleen cells effected recovery of H-2d but not H-2k challenged mice.     

New Method of Isolating Salmonellae from Milk

The use of a cotton gauze swab and subsequent culture of the swab was found to be a more sensitive method for isolating Salmonella from liquid milk than the revised procedure of North. The swab method was found to be as sensitive as the North procedure for recovering Salmonella when incubated at 37 C but more sensitive when incubated at 43 C. Incubation of the swab cultures at the elevated temperature of 43 C gave good results when Salmonella was present at levels as low as one per liter. Swabs exposed to milk contaminated with 100 Salmonella per liter remained positive even when subsequently washed for 2 hr in noncontaminated milk. Bismuth sulfite agar and Brilliant Green sulfadiazine agar were equally effective for isolating Salmonella from broth cultures; use of both media resulted in maximal isolations.     

Abnormalities in synaptonemal complexes in pollen mother cells of a lily hybrid

Two abnormalities, one in lateral elements of synaptonemal complexes the other involving whole complexes, have been studied with the electron microscope in pollen mother cells of the lily hybrid, Lilium aureliensis × L. henryi, which with the light microscope showed almost complete bivalent formation at metaphase. Brief water treatment of pollen mother cells prior to fixation, revealed that the aberrant configurations in lateral elements arose by breakage and subsequent folding of severed fragments up to about 0.8 m long. The abnormality ocurred at recognisable heterologous regions, apparently immediately after pairing. The folded fragments were eliminated from the chromosomes at some time during pachytene. Pseudo pairing was observed after synapsis between either more than one pair of homologues or one pair bent back on themselves, so as to produce polycomplexes. Seemingly, central elements could develop between lateral elements on their outer face under these conditions.     

Gas-liquid chromatographic analysis of cyasin in cycad flour

A method for the quantitative determination of cycasin from cycad flour by gas-liquid chromatography is described. The flour is extracted with 70% ethanol and the residue from the dried extract is directly trimethylsilylated. Androsterone was found to be an excellent internal standard. The average content of cycasin from ten separate analyses of one lot of flour was $\text{0.429 gm}\text{100 gm}$. The method is rapid, sensitive, and not hindered by contaminating compounds.     

A new species of Polymnia (Compositae: Heliantheae) from Mexico

Polymnia mcvaughii from Jalisco, Mexico, is described as new. This herbaceous species appears to belong in the mainstream of evolution within the genus. It exhibits marked affinities to several species, but most closely resemblesP. oaxacana Schultz-Bip. Illustrations of important features are included, along with a list of key characteristics.     

中国东北地区常见有瓣蝇类调查初步报告

与人类杂处的蝇类,在我国东北地区的分布情况尚少系统调查。作者于1956年5月、8月曾赴内蒙东北部(伊图里河、图里河),6月、7月赴营口、盘山(田庄台),借这些机会,顺便采集了蝇类标本;同年9月组内同志去绥中也采回部分标本;1957年5月至10月作者又赴吉林、辽宁两省各地进行了蝇类调查。其中有瓣蝇类已经定名的共计5科26属68种,有6种为国内新记录。兹将结果报告如下:     

我国赫坎按蚊群内中华按蚊不同类型的研究——Ⅳ.幼虫形态的比较

对于赫坎按蚊群内(Anopheles(A.)hyrcanus group.)用四龄幼虫的形态来区别不同种型,在国外曾有若干报导,如马来亚(Reid,1953;1963)、日本(Otsuru and Ohmori,1960)、菲律宾(Baisas et al.,1936等)及印澳(Bonne-Wepsrer and Swellengrebel,1953)等,但在国内对这方面的研究很少。1938年林樑城和姚永政对于南京地区中华按蚊(统称)幼