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排序方式: 共有451条查询结果,搜索用时 15 毫秒
1.
Anaerobic biodegradability of polyvinyl alcohol 总被引:4,自引:0,他引:4
Summary Biodegradability of polyvinyl alcohol (PVA) under anaerobic conditions was demonstrated using anaerobic river sediments and anaerobically treated activated sludge from a sewage treatment plant. PVA having molecular weights of 2000 and 14000 was over 60% biodegraded as determined by TOC. 相似文献
2.
3.
Kazuo Ota Soji Kurita Kazumasa Yamada Tohru Masaoka Yoshiro Uzuka Nobuya Ogawa 《Cancer immunology, immunotherapy : CII》1986,23(1):5-10
Summary In a cooperative randomized control study of immunotherapy with bestatin in combination with chemotherapy in adults with acute nonlymphocytic leukemia (ANLL), 101 patients (48 in the bestatin group and 53 in the control group) out of 115 patients registered were evaluated as eligible. The bestatin group achieved a statistically significant prolongation of survival compared with the control group in overall ANLL and acute myelogenous leukemia. In the analysis of patient age, the bestatin group achieved a statistically significant prolongation of both the remission duration and survival in patients aged 50 to 65 years, while the differences were not significant in the 15 to 49 age group. The bestatin group tended to achieve a higher rate of reinduction of remission in patients who had recurrence of leukemia. Side effects developed in only 5 (9.6%) of 52 patients treated with bestatin. None of these side effects were particularly serious in nature. It is concluded that bestatin is useful for prolongation of survival of adult patients with ANLL, making for a longer remission duration especially in elderly patients and with few side effects. 相似文献
4.
Chloroplast DNA phylogeny of Asian Bamboos (Bambusoideae,Poaceae) and its systematic implication 总被引:1,自引:0,他引:1
The bamboo is usually classified as a subfamily Bambusoideae of Poaceae, and includes approximately 20 genera and 300 species.
To estimate phylogenetic relationships among these genera, we examined restriction site mutations of cpDNA for 16 Asian genera.
In the cladogram obtained, the Bambosoideae was divided into two major lineages, one includingPleioblastus, Pseudosasa, Semiarundinaria, Shibataea, Phyllostachys, Sasa, Sinobambusa, Chimonobambusa, Arthrostylidium, andYushania, and the other consisting ofBambusa, Gigantochloa, Dendrocalamus, Thyrostachys, Melocanna, andSchizostachyum. Monophylly of each clade was supported by 83% and 98% bootstrap probability, respectively. The present result supports monophylly
of Arundinarieae of Potztal's (1964) classical system, but does not support his treatment to recognize Dendrocalameae. 相似文献
5.
Yoshihisa Iwamoto Yusaku Suzuki Akinobu Kurita Yoko Watanabe Tadayori Shimizu Hirohisa Ohgami Yasutake Yanagihara 《Microbiology and immunology》1995,39(11):831-837
A new species, Vibrio trachuri sp. nov., was isolated from the cultured Japanese horse mackerel (Trachurus japonicus). These Vibrio were Gram negative, motile rods and formed yellow colonies on BTB teepol and TCBS plate, turned TSI medium to yellow and was sensitive to 150 μM O/129 (2,4-diamino-6,7-diisopropyl pteridine phosphate) like Listonella anguillarum which has been described as Vibrio anguillarum. However, the results of VP test and decarboxylation of lysine or dihydrolation of arginine suggested that these Vibrio are rather closely related to V. parahaemolyticus. DNA similarity determined by the microplate hybridization technique revealed that these Vibrio are genetically quite distant from Listonella anguillarum or V. parahaemolyticus and rather close to V. harveyi, although there was no Vibrio species which had more than 70% similarity value. From these results we propose to nominate Vibrio trachuri sp. nov. for this new Vibrio species. 相似文献
6.
Le Van Phung Tran Thi Bich Chi Hisako Hotta Eiko Yabuuchi Ikuya Yano 《Microbiology and immunology》1995,39(2):105-116
Viet nam is known as an endemic area of melioidosis but its etiologic agent originated in Viet nam was not extensively studied. For the first time, we analyzed the cellular lipid and fatty acid compositions of 15 Vietnamese isolates of Burkholderia pseudomallei, 10 from humans and 5 from the environment. Cellular lipid compositions were analyzed by two-dimensional thin-layer chromatography on silica gel G plates. Cellular fatty acid methyl esters were analyzed by gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS). The major lipids in all the isolates were phosphatidylglycerol (PG), two forms of phosphatidylethanolamine (PE-1 and PE-2), and two forms of ornithine-containing lipid (OL-1 and OL-2). PE-1 contained non-hydroxy fatty acids at both sn-1 and ?2 positions, while PE-2 possessed 2-hydroxy fatty acids and non-hydroxy fatty acids in a ratio of 1: 1. Since snake venom phospholipase A2 digestion of PE-2 liberated 2-hydroxy fatty acids, it was confirmed that these acids are at the sn-2 position of glycerol moiety. In both OL-1 and OL-2, amide-linked fatty acid was 3-hydroxy palmitic acid (3-OH-C16: 0), while ester-linked fatty acids were non-hydroxy acids in OL-1 and 2-hydroxy acids in OL-2. The total cellular fatty acid compositions of the test strains were characterized by the presence of 2-hydroxy palmitic (2-OH-C16: 0), 2-hydroxy hexadecenoic (2-OH-C16: 1), 2-hydroxy octadecenoic (2-OH-C18: 1), 2-hydroxy methylene octadecanoic (2-OH-C19CPA), 3-hydroxy myristic (3-OH-C14: 0) and 3-hydroxy palmitic (3-OH-C16: 0) acids. There were significant differences in the concentration of hexadecenoic (C16: 1), methylene hexadecanoic (C17CPA), octadecenoic (C18: 1) and methylene octadecanoic (C19CPA) acids among the Vietnamese isolates of B. pseudomallei. However, no significant difference was observed in cellular lipid and fatty acid components between strains of human and environmental origins. 相似文献
7.
Le Van Phung Yuki Han Shiro Oka Hisako Hotta Michael D. Smith Prapit Theeparakun Eiko Yabuuchi Ikuya Yano 《FEMS immunology and medical microbiology》1995,12(3-4):259-264
Abstract The serodiagnosis of melioidosis is commonly performed with tests using protein or polysaccharide as antigen. However, due to the low sensitivity, specificity and difficulty in the preparation of the antigens, more simple, precise and reproducible diagnostic tests were required. A purified glycolipid antigen (GL) which is a specific lipid component of Burkholderia pseudomallei has been used in an ELISA. With this antigen, specific immunoglobulin G (IgG) was detected in 49 out of 50 melioidosis sera. IgG was also detected in 2 out of 185 (Japanese) and 16 out of 181 (Vietnamese) control sera. Thus, the sensitivity was 98.0%, and specificity was 98.9% and 91.1% in the Japanese and Vietnamese sera, respectively. When the ELISA and indirect haemagglutination (IHA) tests were combined, a sensitivity of 100% and specificity of 97.8% were achieved. The advantages of the glycolipid antigen are ease of preparation, stability, high sensitivity and specificity. 相似文献
8.
Ikuya Yano Sadao Imaizumi Ikuko Tomiyasu Eiko Yabuuchi 《FEMS microbiology letters》1983,20(3):449-453
Abstract The occurrence of free ceramides was shown in the chloroform-methanol extractable lipids of 16 strains of Sphingobacterium including three species: S. versatilis, S. multivorum and S. mizutae . The predominant long-chain base was identified as a branched-chain, saturated dihydroxy base with a carbon chain consisting of 17 carbon atoms, while the most abundant fatty acid was 2-hydroxy-13-methyltetradecanoic acid. The major molecular species of the intact ceramides were identified as LCB- d - iso -17 : 0-2-OH iso -15 : 0FA, LCB- d - iso -17 : 0- iso -15 : 0FA and LCB- d -n16 : 0- iso -15 : 0FA. 相似文献
9.
To investigate the biological effects of exposure to feeble high frequency electromagnetism, skin surface temperature, blood vessel (arterioles and venules) diameter were examined, using infrared thermography, a laser doppler flowmeter, and a video microscope, respectively, in the ear of rabbits. After exposing the ear of rabbits to high frequency electromagnetism value of 9 MHz for 15 minutes, continued rising of local temperature was demonstrated. Though dilatation of arterioles was not seen. In addition, venules tended to dilate and blood flow also to increase, and microcirculation was accelerated at the site where electromagnetism was exposed. Hazardous effects of long term exposures of high frequency electromagnetism (9 MHz for 30 days, 8 hours/day) on guinea pigs were not observed in their behavior, food consumption, body and organ weights, hematological and biochemical values, macroscopic and microscopic findings on autopsy. 相似文献
10.
T Suzuki K Tamai Y Kodama A O Asita A Matsuoka T Sofuni M Kurita H Ohtsuki T Hiwatashi M Hayashi 《Mutation research》1992,278(2-3):169-173
Micronucleus assays using mouse peripheral blood stained vitally on acridine orange (AO)-coated slides were evaluated at two laboratories with 7,12-dimethylbenz[a]anthracene (DMBA) and compared with the standard bone marrow assay. DMBA was administered by single intraperitoneal injection to CD-1 mice at doses ranging from 5 to 80 mg/kg, then 5 microliters of peripheral blood was sampled from a tail vein at 24, 48, 72, 96, and 120 h after treatment. Similar incidences of micronucleated young erythrocytes were observed in peripheral blood reticulocytes and bone marrow polychromatic erythrocytes. The dose response of micronucleated reticulocytes was delayed compared to that of micronucleated polychromatic erythrocytes. The dose-response curves after treatment with DMBA differed depending on the sampling times, which revealed the difficulty of obtaining accurate dose-response relations in the micronucleus assay. The present result demonstrated that the simple and rapid AO supravital staining method is a valuable and easier method for obtaining dose- and time-response data for quantification of micronucleus induction by chemicals. 相似文献