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1.
Sachiko Goto Akiyoshi Tsuji Teiko Murai Minoru Nishida Hiroko Tsukano Haruo Watanabe 《Journal of infection and chemotherapy》1998,4(1):16-19
Although there are effective antibacterial agents against plague, newer antibacterial agents have been developed which show
more potent activity against other bacterial organisms, but have not been tested againstYersinia pestis. A strain ofYersinia pestis was selected (no. 22; National Institute of Infectious Diseases, Tokyo, Japan) that caused a systemic infection in mice.Y. pestis no. 22 was intraperitoneally inoculated into DDY-strain mice, and 13 oral or 6 injectable antibacterial drugs given to the
infected mice at varying doses 1 and 24 hours after infection. Levofloxacin, sparfloxacin and ofloxacin were the most effective
oral agents against the infection, and prulifloxacin and pazufloxacin were also effective but to a lesser extent. Also, gentamicin
and arbekacin were the most potent injectable antibacterial agents againstY. pestis. These results suggest that there are several new drugs, both oral and injectable, which exert excellent in vivo antibacterial
activity against a mouse infection model and may be useful for the clinical treatment of plague. 相似文献
2.
ASTROCYTE-CONDITIONED MEDIUM INDUCES BLOOD-BRAIN BARRIER PROPERTIES IN ENDOTHELIAL CELLS 总被引:6,自引:0,他引:6
3.
Yasuhiro Sano Shigeharu Yamashiro Asuka Komano Hisashi Maruko Hiroshi Sekiguchi Yasuo Takayama Ryoji Sekioka Kouichiro Tsuge Isaac Ohsawa Mieko Kanamori-Kataoka Yasuo Seto Akiyoshi Satoh 《Forensic Toxicology》2007,25(2):76-79
We previously reported that the Guardian Bio-Threat Alert (BTA) system could detect (detection limit: about 0.1 μg/ml) staphylococcal
enterotoxin B (SEB), botulinum toxins (BTX) A and B, and ricin, with no interference by white-powdered materials or colored
matrices. In this study, the capability of the BTA system was further assessed. With 10 min of preheating at 60°C, all toxins
could be detected, but with preheating at 80°C, BTX A and B and ricin became undetectable. About 20% SEB could be detected
after heating at 80°C, but this detection ability was completely removed after heating at 100°C. The effects of chemicals
usually used for decontamination, such as sodium hypochlorite, hydrogen peroxide, formaldehyde, and sodium nitrite, on the
detectability of SEB, BTX A, or ricin in the BTA system were also tested. The concentrations giving 50% line intensity for
SEB, BTX A, and ricin were 3.1, 11, and 15 μM for sodium hypochlorite and 88, 210, and 60 mM for formaldehyde, respectively.
The addition of hydrogen peroxide or sodium nitrite did not decrease the detectability even when used at high concentrations. 相似文献
4.
5.
Clonal growth of hepatitis B virus-integrated hepatocytes in cirrhotic liver nodules. 总被引:6,自引:0,他引:6
A total of 83 cirrhotic nodules (pseudolobules) individually collected from 11 cirrhotic livers of hepatitis B virus carrier patient were analyzed for the frequency and mode of hepatitis B virus integration as well as histological features. Southern blot analysis disclosed discrete bands at higher molecular weight region in 26 of 83 nodules (31.3%), indicating a clonal growth of hepatocytes with viral integration. Considerable variation (0-75%) existed in the positive rates for discrete bands in nodules among livers. Molecular cloning revealed the sequence flanking an integrated viral sequence to be host DNA and thus confirmed true integration. Histological analysis, however, did not reveal any neoplastic-appearing foci of growth within nodules, despite the fact that the detection sensitivity would predict clones of more than 10(5) cells to give rise to clonal integration patterns on Southern blot analysis. The question of whether clonal expansion of hepatocytes reflects any viral integration-associated growth advantage and/or a preneoplastic condition awaits future studies. 相似文献
6.
Haruo Nagayama Kounosuke Tsuchiyama Kenji Yamada Jotaro Akiyoshi 《Progress in neuro-psychopharmacology & biological psychiatry》1991,15(6):735-744
1. In our series of experiments the role of serotonin in human depression was studied by using animal models of depression.
2. The results of these studies support the hypothesis that some types of human depression may be primarily due to an excessive transmission of serotonin at the synapse. 相似文献
7.
Y Inoue T Momose K Amo T Ohtake T Watanabe N Kosaka J Nishikawa Y Sasaki 《Kaku igaku. The Japanese journal of nuclear medicine》1992,29(8):955-962
Metabolism of 99mTc-ethyl cysteinate dimer (99mTc-ECD) in blood was studied mainly in vitro. When 99mTc-ECD was mixed with blood taken from 12 subjects, the octanol extraction ratio of ECD (y) decreased rapidly and the octanol extraction ratio-time profile well fitted a monoexponential curve (y = Ae-kt/1000, A, k: constant, t: time after mixing). The k value and hematocrit (Ht) were significantly correlated (k = 0.376Ht-3.27, r = 0.897, p less than 0.001), therefore, it was suggested that the majority of the enzyme which dissolves ECD exists in red blood cells. When ECD was mixed with blood, there were more hydrophilic products of ECD in plasma than those generated by the enzyme in plasma. In vivo input function of 99mTc-ECD was calculated by arterial blood sampling and octanol extraction. The duration of effective input was relatively short, which was attributed to rapid decrease of octanol extraction ratio in vivo. 相似文献
8.
The purpose of this study was to determine whether centrally mediated sympathetic tone exerts compensatory effects on nitrous oxide-induced myocardial depression during high-dose fentanyl anaesthesia. The cardiovascular responses to 60 minutes of nitrous oxide administration after fentanyl, 100 micrograms.kg-1, were examined in 18 dogs with or without autonomic blockade induced by hexamethonium. Decreases of cardiac output and left ventricular stroke work were significantly greater in dogs with autonomic blockade (n = 9) by about 20 per cent of baseline values than in dogs without autonomic blockade (n = 9) at 30, 45, and 60 min. Similarly, left ventricular dP/dt was reduced more in dogs with autonomic blockade than in dogs without autonomic blockade, but this difference was only significant at the 60-min period. It is concluded that the sympathetic nervous system provides partial compensation for myocardial depression induced by nitrous oxide in the presence of high-dose fentanyl, suggesting that large doses of fentanyl do not ablate the centrally mediated sympathomimetic effects of nitrous oxide. 相似文献
9.
Evaluation of renal first pass blood flow with a functional image technique in hypertensive patients
Masatoshi Ishibashi Seiichiro Morita Noriyoshi Umezaki Hisashi Ohtake 《European journal of nuclear medicine and molecular imaging》1988,14(1):25-27
The renal circulation of patients with essential hypertension and renovascular hypertension was evaluated using 99mTc-DTPA. The first renal peak count (the first Cmax; FCmax), time phase distribution (the first Tmax; FTmax), and blood velocity (the FCmax/FTmax) were calculated by digital imaging. This yields a visual image of the renal circulation. We consider that the increase in the renal first pass blood flow in patients with essential hypertension is best observed pixel by pixel. The FCmax and FCmax/FTmax images before and after treatment by percutaneous transluminal renal angioplasty in patients with renovascular hypertension clearly show its therapeutic effect. The FI technique, therefore, has the advantage that it can be performed at the same time as the conventional routine examinations of renal function. This makes it very useful clinically. 相似文献
10.