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排序方式: 共有313条查询结果,搜索用时 15 毫秒
1.
Bacteriocin sensitivity typing according to the method of Traub (Appl. Microbiol. 1971. 21: 837-840) was carried out on 226 clinical isolates of Serratia marcescens obtained from inpatients at Nagasaki University Hospital during the period from January 1976 to December 1978. The isolates were divided into 16 different bacteriocin types, mainly 26, 4, and 9. The distribution of the types suggests that Serratia marcescens infections may be caused by cross infection. Reproducibility of bacteriocin typing and the relationship between serotypes (O-antigen) and bacteriocin types are discussed in regard to the application of this method to the study of nosocomial infections. 相似文献
2.
Tanaka Osamu; Nasu Yutaka; Sonoyama Akiko; Maehara Yasuko; Kobayashi Takako; Nawafune Hidemi; Kugimoto Mamoru 《Plant & cell physiology》1987,28(4):697-702
The flowering of Lemna paucicostata 6746 grown on 14-h photoperiodwas enhanced by the addition of high concentrations of ironto the medium, which also increased the endogenous iron concentration.The addition of asparagine, aspartate, glutamate, -alanine,glycine or serine to the medium also increased the endogenousiron level, resulting in the promotion of flowering. In contrast,the addition of cysteine, cystine, glutamine, arginine, threonineor phenylalanine lowered the endogenous iron level, resultingin the inhibition of flowering. Glycine and asparagine added to the medium during an inductive96-h dark period did not promote iron uptake and had no effecton flowering, but when added during the subsequent 120-h lightperiod, they promoted both iron uptake and flowering response.The increase in the endogenous iron level seems to favor floraldevelopment rather than induction of photoperiodic floweringof Lemna paucicostata 6746. (Received September 8, 1986; Accepted March 31, 1987) 相似文献
3.
M Takahashi T Shimizu K Ooi H Noda T Nasu G Sakaguchi 《Japanese journal of medical science & biology》1988,41(1):21-26
Bacteriological examinations were performed on the first case of infant botulism in Japan (an infant boy aged 79 days at onset of illness). Clostridium botulinum type A toxin and organisms were detected continually in the stools of the infant for at least 31 days and 39 days, respectively. The highest levels of the toxin and of the population of the organisms, 7.8 X 10(4) LD50/g and 1.3 X 10(6) colony forming units (cfu)/g, were detected in the stool specimen taken on the 20th day of illness. Type A organisms were detected also in the honey fed to the infant before onset of illness, teats of his feeding bottle, soil specimens taken at the house entry and the vacuum-cleaner dust. Fecal excretion of the toxin and organisms was no longer detected from the 68th day of illness and he recovered. 相似文献
4.
5.
Yoshihito Suzuki Noboru Murofushi Yun-Hui Zhang Yasutomo Takeuchi 《Journal of Plant Growth Regulation》1994,13(2):63-67
Endogenous gibberellins were analyzed from a parasitic plant, clover broomrape (Orobanche minor Smith), and its host, clover (Trifolium repens L.). Members of both the early-13- and the early-non-hydroxylation pathways were identified from both the parasite and the host (GA12, GA24, GA9 GA4, GA44, GA19, GA20, and GA1 from clover broomrape; GA9, GA4, GA44, GA19, GA20, and GA1 from clover). Quantitative analyses showed that GA44 was present at high levels in both host and parasite. The similarity in the gibberellins suggests the possibility that the major gibberellins in clover broomrape are transported from clover. However gibberellins such as GA58, GA38, and notably GA47 which was identified from a plant for the first time were detected only from clover broomrape, suggesting that the parasite may have the ability to produce at least those gibberellins 相似文献
6.
本文是利用扫描电子显微镜对陆栖恐龙tvrannosaurid与海栖渐增mosasaurid”牙齿结构进行的比较解剖学研究。化石采自加拿大RedDeerhiverValley上白里统Horse-shoeCanyon组。通过研究地层中出现的生物化石,特别是动物牙齿的组织结构,可以了解动物为了适应生活环境而发生的进化过程,也可以推测它们的系统发育关系。tyrannosaund与mosas。id都拥有锥状的同形齿,牙齿侧向扁平,且略向后弯曲。研究结果确认了tyrannosaurid的牙齿由于薄层的无柱釉质bPrismaticenamel)向齿质的侵人而造成许多的凹凸构造,此锯齿状构造沿着牙齿的前后缘,由牙齿的顶端分布至基部。因此tyrannosaurid的牙齿呈现着锐利的切缘;在这些凹凸状切缘的沟与小窝的深部可观察到有机物的沉积。但是类似的锯齿状构造只能在齿冠呈钝圆状的mosasaurid牙齿的基部附近观察到。我们以扫描电子显微镜(SEM)检索,确认两爬行类的齿质皆是属于中间型的真性齿质(intermediatetypeorthodentine);所谓orthodentine即是细管齿质(tubulardentine)。tyrannosaurid的真性齿质的齿质小管只在齿质一釉质相接处Uentino—enamaljunction)附近放散出规则性的分歧与末枝。但mosasaurid的真性齿质的齿质J。管,在齿质的中间层与表层中,呈现着由复杂 相似文献
7.
Tanaka Osamu; Nasu Yutaka; Takimoto Atsushi; Kugimoto Mamoru 《Plant & cell physiology》1982,23(7):1291-1296
The effect of copper on flowering and growth of Lemna paucicostata6746 and Lemna gibba G3 in a copper-containing medium is nullifiedby the addition of EDTA, ammonium ions or salicylic acid tothe medium or a decrease in its nitrate concentration. Thesefactors were examined for their effects on the absorption ofcopper by the plants. The addition of EDTA to the medium completelyinhibited the absorption of copper in both species, thus eliminatingthe copper effect. Ammonium ions also inhibited copper absorption,their effectiveness rising with their concentration. Loweringthe nitrate concentration in the medium nullified the coppereffect on flowering in L. paucicostata 6746, and the additionof salicylic acid to the medium also nullified the copper effectin L. gibba G3, both without affecting the absorption of copper. (Received June 7, 1982; Accepted August 27, 1982) 相似文献
8.
Yasutomo Hoshika Makoto Watanabe Naoki Inada Takayoshi Koike 《Annals of botany》2013,112(6):1149-1158
Background and Aims
Resistance of plants to ozone stress can be classified as either avoidance or tolerance. Avoidance of ozone stress may be explained by decreased stomatal conductance during ozone exposure because stomata are the principal interface for entry of ozone into plants. In this study, a coupled photosynthesis–stomatal model was modified to test whether the presence of ozone can induce avoidance of ozone stress by stomatal closure.Methods
The response of Siebold''s beech (Fagus crenata), a representative deciduous tree species, to ozone was studied in a free-air ozone exposure experiment in Japan. Photosynthesis and stomatal conductance were measured under ambient and elevated ozone. An optimization model of stomata involving water, CO2 and ozone flux was tested using the leaf gas exchange data.Key Results
The data suggest that there are two phases in the avoidance of ozone stress via stomatal closure for Siebold''s beech: (1) in early summer ozone influx is efficiently limited by a reduction in stomatal conductance, without any clear effect on photosynthetic capacity; and (2) in late summer and autumn the efficiency of ozone stress avoidance was decreased because the decrease in stomatal conductance was small and accompanied by an ozone-induced decline of photosynthetic capacity.Conclusions
Ozone-induced stomatal closure in Siebold''s beech during early summer reduces ozone influx and allows the maximum photosynthetic capacity to be reached, but is not sufficient in older leaves to protect the photosynthetic system. 相似文献9.
10.
Tohru Taniguchi Mai Asahata Akihito Nasu Yukatsu Shichibu Katsuaki Konishi Kenji Monde 《Chirality》2016,28(7):534-539
Separation of the diastereomers of glycosyl sulfoxides differing in the sulfur chirality has been difficult. This article presents a fast and scalable method for their diastereoseparation using a chiral stationary phase. The usefulness of this method was demonstrated in a 500‐mg scale separation within 20 min, and in the separation of trisaccharyl sulfoxide diastereomers. Chirality 28:534–539, 2016. © 2016 Wiley Periodicals, Inc. 相似文献