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排序方式: 共有598条查询结果,搜索用时 15 毫秒
81.
Koichi Izumikawa Yoichi Hirakata Toshiyuki Yamaguchi Ryoji Yoshida Michiko Nakano Junichi Matsuda Chikako Mochida Shigefumi Maesaki Kazunori Tomono Yasuaki Yamada Takayoshi Tashiro Shigeru Kohno Shimeru Kamihira 《Microbiology and immunology》1998,42(10):677-681
A total of 19 Escherichia coli O157 isolates were obtained in Nagasaki Prefecture, in the southwestern part of Japan, between 1990 and 1996. Pulsed-field gel electrophoresis (PFGE) and computer-assisted analysis were applied to determine genetic relationships among these strains. Fragment patterns of the isolates in Nagasaki, as determined by PFGE, were compared with those of isolates in other areas where large outbreaks and sporadic cases of E. coli O157 infection occurred. Similarity values of all the strains isolated in Nagasaki Prefecture were over 0.65 except for E. coli O26. Some strains were identical to the strains isolated from the areas where large outbreaks occurred. All strains were susceptible to ampicillin, fosfomycin, minocycline, amikacin, ofloxacin and sulfamethoxazole-trimethoprim. 相似文献
82.
Host DNA Synthesis-Suppressing Factor in Culture Fluid of Tissue Cultures Infected with Measles Virus 总被引:1,自引:1,他引:0
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Host DNA synthesis is suppressed by the culture fluid of cell cultures infected with measles virus. This activity in the culture fluid is initiated somewhat later than the growth of infectious virus. Ninety percent of host DNA synthesis in HeLa cells is inhibited by culture fluid of 3-day-old cell cultures of Vero or HeLa cells infected with measles virus. This suppressing activity is not a property of the virion, but is due to nonvirion-associated component which shows none of the activities of measles virus such as hemagglutination, hemolysis, or cell fusion nor does it have the antigenicity of measles virus as tested by complement-fixation or hemagglutination-inhibiting antibody blocking tests. Neutralization of the activity of this component is not attained with the pooled sera of convalescent measles patients. This component has molecular weights of about 45,000, 20,000, and 3,000 and appears to be a heat-stable protein. The production of host DNA suppressing factor (DSF) is blocked by cycloheximide. Neither UV-inactivated nor antiserum-neutralized measles virus produce DSF. Furthermore, such activity of nonvirion-associated component is not detected in the culture fluid of cultures infected with other RNA viruses such as poliovirus, vesicular stomatitis virus, or Sindbis virus. 相似文献
83.
Atsuko Takagi Yasuyuki Ikeda Kunihisa Kobayashi Kazuhiro Kobayashi Yoshihiko Ikeda Junji Kozawa Hideyuki Miyauchi Ming Li Chikako Hashimoto Yasuhiro Hara Satoshi Yamaguchi Akira Suzuki Tatsushi Toda Hironori Nagasaka Ken-ichi Hirano 《Biochemical and biophysical research communications》2018,495(1):646-651
Triglyceride deposit cardiomyovasculopathy (TGCV) is a rare and newly identified disease among patients requiring cardiac transplantation. TGCV is characterized by cardiomyocyte steatosis and triglyceride (TG)-deposit atherosclerosis, resulting from the abnormal intracellular metabolism of TG. TGCV is classified into primary and idiopathic types. Primary TGCV carries ultra-rare genetic mutations in the adipose triglyceride lipase (ATGL), a rate-liming enzyme that hydrolyzes intracellular TG in adipose and non-adipose tissues. Idiopathic TGCV, first identified among autopsied individuals with diabetes mellitus (DM) with severe heart diseases, shows no ATGL mutations and its causes and underlying mechanisms are still unknown. TGCV is difficult to diagnose in daily clinics, thereby demanding feasible diagnostic procedures. We aimed to develop an assay to measure ATGL activity using peripheral leucocytes. Human his6-ATGL was expressed in COS1 cells, purified to homogeneity, and used to raise a polyclonal antibody neutralizing TG-hydrolyzing activity of ATGL. We developed a selective immunoinactivation assay (SIIA) for the quantitation of ATGL activity in cell lysates of leucocytes by the antibody neutralizing ATGL activities. ATGL activity was measured in 13 idiopathic TGCV patients, with two patients with primary TGCV as the negative control. Healthy (non-DM) and DM controls without heart diseases were also subjected. The developed SIIA assay revealed significant reduction in ATGL activity in leucocytes from patients with idiopathic TGCV who did not carry ATGL mutations as compared with non-DM and DM controls. Thus, ATGL in leucocytes may be an important biomarker for the diagnosis of TGCV and our assay may provide insights into pathophysiology and elucidate the underlying mechanism of TGCV and related disorders. 相似文献
84.
The bacterial community structures in four Japanese split-type air conditioners were analyzed using a next-generation sequencer. A variety of bacteria were detected in the air filter of an air conditioner installed on the first floor. In the evaporator of this air conditioner, bacteria belonging to the genus Methylobacterium, or the family of Sphingomonadaceae, were predominantly detected. On the other hand, the majority of bacteria detected in the air filters and evaporators of air conditioners installed on the fifth and twelfth floors belonged to the family Enterobacteriaceae. The source of bacteria belonging to the family Enterobacteriaceae may have been aerosols generated by toilet flushing in the buildings. Our results suggested the possibility that the bacterial contamination in the air conditioners was affected by the floor level on which they were installed. The air conditioner installed on the lower floor, near the ground, may have been contaminated by a variety of outdoor bacteria, whereas the air conditioners installed on floors more distant from the ground may have been less contaminated by outdoor bacteria. However, these suppositions may apply only to the specific split-type air conditioners that we analyzed, because our sample size was small. 相似文献
85.
86.
Tashiro T Kawakita C Takai C Yoshida T Sakiyama S Kondo K Sano N 《Acta cytologica》2007,51(5):820-824
BACKGROUND: Although the histologic features of malignant peripheral nerve sheath tumor (MPNST) have been described, the cytologic features of primary pulmonary MPNST have not been reported in the literature. CASE: We report a case of primary pulmonary MPNST in a 78-year-old man. Follow-up computed tomography of colon cancer, renal cancer, penile cancer and gingival cancer revealed a nodular lesion, 12 mm in diameter, in the right upper lobe of the lung. In frozen section, a diagnosis of malignant neoplasm, not otherwise specified, was rendered for the imprinting specimen and histologic specimen. Imprinting specimens were composed of small cellular aggregates and discohesive neoplastic cells with obvious malignant features. Histologically, spindle cells with pleomorphic nuclei arranged infascicular patterns and multinucleated tumor giant cells were also observed. More than 25 mitotic figures were observed per 10 high-power fields. Tumor cells were positive only for vimentin and S-100, and the Ki-67 labeling index was 10%. Clinical and imaging investigation failed to identify an alternative primary site. We histologically diagnosed this case as primary pulmonary MPNST. CONCLUSION: MPNST has a varied cytomorphology with frank nuclear atypia showing no definite differentiation. Multinucleated neoplastic giant cells with immunopositivity for S-100 may permit more accurate diagnosis of MPNST. 相似文献
87.
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89.
Wen XP Pang XM Matsuda N Kita M Inoue H Hao YJ Honda C Moriguchi T 《Transgenic research》2008,17(2):251-263
An apple spermidine synthase (SPDS) gene (MdSPDS1) was verified to encode a functional protein by the complementation of the spe3 yeast mutant, which lacks the SPDS gene. To justify our hypothesis that apple SPDS is involved in abiotic stress responses and to obtain transgenic fruit trees
tolerant to abiotic stresses as well, MdSPDS1-over-expressing transgenic European pear (Pyrus communis L. ‘Ballad’) plants were created by Agrobacterium-mediated transformation. A total of 21 transgenic lines showing various spermidine (Spd) titers and MdSPDS1 expression levels were obtained. Selected lines were exposed to salt (150 mM NaCl), osmosis (300 mM mannitol), and heavy
metal (500 μM CuSO4) stresses for evaluating their stress tolerances. Transgenic line no. 32, which was revealed to have the highest Spd accumulation
and expression level of MdSPDS1, showed the strongest tolerance to these stresses. When growth increments, electrolyte leakage (EL), and values of thiobarbituric
acid reactive substances (TBARS) were monitored, line no. 32 showed the lowest growth inhibition and the least increase in
EL or TBARS under stress conditions. Spd titers in wild-type and transgenic lines showed diverse changes upon stresses, and
these changes were not consistent with the changes in MdSPDS1 expressions. Moreover, there were no differences in the sodium concentration in the shoots between the wild type and line
no. 32, whereas the copper concentration was higher in the wild type than in line no. 32. Although the mechanism(s) underlying
the involvement of polyamines in stress responses is not known, these results suggest that the over-expression of the SPDS gene substantially increased the tolerance to multiple stresses by altering the polyamine titers in pear. Thus, MdSPDS1-over-expressing transgenic pear plants could be used to improve desert land and/or to repair polluted environments.
Xiao-Peng Wen and Xiao-Ming Pang contributed equally to this work. 相似文献
90.
Kondo T Nekado T Sugimoto I Ochi K Takai S Kinoshita A Hatayama A Yamamoto S Kishikawa K Nakai H Toda M 《Bioorganic & medicinal chemistry》2008,16(4):1613-1631
A series of (4beta-substituted)-L-prolylpyrrolidine analogs lacking the electrophilic nitrile function were synthesized and their dipeptidyl peptidase IV (DPP-IV) inhibitory activity and duration of ex vivo activity were evaluated. Structural optimization of a N-(3-phenyl-1,2,4-thiadiazol-5-yl)piperazine analog 8, which was found by high-speed analog synthesis, was carried out to improve the potency and duration of action. A representative compound 26 was evaluated to assess its effect on the plasma glucose level after the oGTT (oral glucose tolerance test) in normal rats. Structure-activity relationships (SAR) are also presented. 相似文献