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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.
Toshifumi Takao Noriko Tominaga Yasutsugu Shimonishi Saburo Hara Takashi Inoue Akio Miyama 《Biochemical and biophysical research communications》1984,125(3):845-851
A heat-stable enterotoxin was isolated and purified from the culture supernatant of by reversed-phase high-performance liquid chromatography. The amino acid sequence of the purified toxin was determined to be as follows: Gln-Ala-Cys(X)-Asp-Pro-Pro-Ser-Pro-Pro-Ala-Glu-Val-Ser-Ser-Asp-Trp-Asp-Cys-Cys-Asp-Val-Cys-Cys-Asn-Pro-Ala-Cys-Ala-Gly-Cys (X: not determined). The C-terminal sequence containing 6 half-cystine residues was highly homologous to that of heat-stable enterotoxin of enterotoxigenic 相似文献
5.
Saburo Sone Gabriel Lopez-Berestein Isaiah J. Fidler 《Cancer immunology, immunotherapy : CII》1986,21(2):93-99
Summary We investigated whether human peripheral blood monocytes isolated by centrifugal elutriation from healthy donors could be acitivated to become tumoricidal and release tumor cytolytic factor (TCF) subsequent to incubation with recombinant human interferon-gamma (r-IFN-) or a derivative of muramyl dipeptide (nor-MDP), or both. Blood monocytes incubated in endotoxin-free medium containing up to 1000 U/ml of r-IFN- or in medium containing less than 1 g/ml of nor MDP were not activated to lyse radiolabeled allogeneic human tumor cells. In contrast, the incubation of monocytes with various dose combinations of r-IFN- and nor-MDP generated significant direct cytotoxic activity as well as production of TCF. Preincubation of the r-IFN- and nor-MDP mixture with polymyxin B did not inhibit the synergism, thus ruling out the possibility that the process was due to endotoxin contamination. TCF harvested from monocyte culture supernatants was cytolytic against five allogeneic tumor targets, but not against a nontumorigenic cell line. Collectively, the data demonstrate that r-IFN- can prime human blood monocytes to allow their activation by synthetic nor-MDP.On leave from the Department of Internal Medicine, The University of Tokushima School of Medicine, Kuramoto-cho, Tokushima 770, Japan 相似文献
6.
Saburo Sone Teruhiro Utsugi Priti Tandon Mitsumasa Ogawara 《Cancer immunology, immunotherapy : CII》1986,22(3):191-196
Summary Studies were performed on the activation of human blood monocytes to the antitumor state by a dried preparation of multilamellar vesicle (MLV) liposomes in which synthetic muramyl tripeptide phosphatidylethanolamine (MTP-PE) was inserted directly into the liposome membrane. Dried liposomes composed of synthetic phospholipids [phosphatidylcholine (PC) and phosphatidylserine (PS) in a molar ratio of 7:3] were prepared by lyophilization. Dried liposome-MTP-PE was found to be superior in several ways to free desmethyl muramyl dipeptide (norMDP) or conventional liposome-MTP-PE, prepared immediately before use. First, dried lipsome-MTP-PE was stable and strongly activated monocytes when stored for over 3 months in a freezer at –°C or even in suspension at 4°C. Second, human monocytes in suspension, as well as in the adherent form, were activated to the tumoricidal state by interaction for at least 4 h with the dried preparation of liposome-MTP-PE. Third, monocytes activated with the dried liposome-MTP-PE or conventionally prepared liposome-MTP-PE maintained their tumoricidal activity for a longer period (4 days) than those activated with free norMDP. These results indicate that the dried preparation of liposome-MTP-PE can be stored for a long time, has a reproducible effect that can be standardized and should be valuable for in situ activation of human monocytes to the tumoricidal state, which is associated with eradication of cancer metastases. 相似文献
7.
A vitamin B12-producing and hydrocarbon-utilizing bacterium, Corynebacterium simplex, accumulated an appreciable amount of cobalt-porphyrin in cultural filtrates when grown on a n-hexadecane medium containing sufficient amounts of cobaltous sulfate and an appropriate detergent. When grown without the detergent, the cobalt-porphyrin was found only in the cells of the organism. In the latter case, the content of cobalt-porphyrin was comparable to that of vitamin B12 and 7 times lower than that of iron-porphyrin. Though the organism required cobaltous sulfate for optimal growth, the requirement could be efficiently replaced by the supplementation of cobalt-porphyrin and partly of vitamin B12. The porphyrin moieties of extra- and intracellular cobalt-porphyrin were identified as coproporphyrin III in both cases. 相似文献
8.
Power requirements in the agitation of non-Newtonian fermentation broths with and without aeration were measured by a strain gage-type dynamometer. Broth from the production of gluc-amylase by Endomyces species and carboxymethyl cellulose solutions were used as non-Newtonian fluids. In gas–liquid agitation systems, the correlation between Pg and P02 ND3/Q0.56 observed by Michel and Miller was found to be applicable to non-Newtonian fluids in laminar and transition regions. This was particularly true for fluids with apparent viscosities larger than 300 cp. The impeller diameter and impeller blade width had considerable effects on power consumption in a nongassed system. It was suggested, therefore, that Pg/P0 should be correlated by a dimensionless term involving some impeller-size factors. 相似文献
9.
10.
Summary The submicroscopic structure of the nerve cells in the planarian brain was studied. Close similarities with neurons of other invertebrates were noted. In the cytoplasm of the planarian nerve cells there are at least three types of vesicular inclusions: 1) Clear vesicles (200–800 Å in epon embedded tissue) similar in morphological appearance to classical synaptic vesicles. These have generally some content of extremely low density but occasionally a dense core. 2) Dense vesicles (400–1,200 Å in epon embedded tissue) containing highly osmiophilic granules. Between the limiting membrane of the vesicle and the granule there is always a clear rim of variable width. These vesicles closely resemble synaptic vesicles described in vertebrate adrenergic endings. 3) Neurosecretory vesicles (600–1,300 Å in Vestopal embedded tissue) similar to elementary granules observed in neurosecretory systems in vertebrates and invertebrates. All three vesicle types have the same mode of origin from the Golgi membranes. All are present in the nerve cell processes of the neuropil as well as in the perikarya. Any given perikaryon or axon contains only one of the three vesicle types. All of these vesicles are considered to be discharged into the axons from their site of origin within the perikaryon. 相似文献