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排序方式: 共有5522条查询结果,搜索用时 15 毫秒
21.
22.
Y Inamoto T Chiba K Sakane T Kamimura T Takaya 《Yakugaku zasshi : Journal of the Pharmaceutical Society of Japan》1990,110(4):246-257
Various 7 beta-[2-(2-aminothiazol-4-yl)-2-substituted acetamido]-3-vinyl-3-cephem-4-carboxylic acid derivatives (Ia--e, IIa--g) were synthesized in order to find a new orally active cephalosporin improving the antibacterial activity of cefixime (CFIX) against Staphylococcus aureus. These derivatives include three types of alpha-substituted 2-(2-aminothiazol-4-yl)acetyl side chain; i) mono or non substituted acetyl moiety, ii) carboxyalkoxyimino acetyl moiety, iii) phosphonomethoxyimino and hydroxyimino acetyl moiety. Their structure-activity relationships and urinary recoveries in rats were studied. As a result, the compound with a hydroxyimino acetyl side chain (IIg, FK482) showed good oral absorption and excellent antibacterial activity against both gram-positive and gram-negative bacteria and was selected as a candidate for clinical trial. 相似文献
23.
Summary. Three non-sense mutants of varicella-zoster virus (VZV) thymidine kinase (TK) gene, VZTK325, VZTK278 and VZTK224, were isolated. The mutants had a single nucleotide substitution at codons 326, 279 and 225, which changed the codon of TGG
(tryptophan) to the stop codon TGA. The wild type (WT) and mutant TKs were expressed in E. coli cells and their characteristics were evaluated. VZTK224 lost TK activity, but VZTK325 and VZTK278 maintained 74.8% and 21.2% of the WT TK activity. On the other hand, all mutants lost the thymidylate kinase activity. Moreover,
VZTK325 and VZTK278 polypeptides were heat-labile. These data suggest that the carboxy-terminal portion of herpesvirus TK plays an important
role in the stable folding of TK and thymidylate kinase activity.
Received April 21, 1997 Accepted June 16, 1997 相似文献
24.
Kazuro Sugi Kouichi Nawata Kazuhiro Ueda Yoshikazu Kaneda Sumihiko Nawata Atsunori Oga Kensuke Esato 《Surgery today》1997,27(7):666-668
We report herein the case of a 70-year-old man in whom a chest wall implantation of adenocarcinoma of the lung at the drainage
tube site was found 4 months after a right lower lobectomy with mediastinal lymph node dissection had been performed for adenocarcinoma
of the right lower lobe. The lesion was successfully treated by tumor extirpation. We believe that tumor seeding to the chest
wall occurred at the time of thoracotomy. To prevent such tumor seeding, the pleural cavity should be washed out routinely
with a massive volume of physiological saline solution prior to closure of the chest wall. 相似文献
25.
Responses of isolated canine ophthalmic and ciliary arteries to vasoactive substances 总被引:2,自引:0,他引:2
The effects of 11 vasoactive substances were compared on the isolated and perfused canine internal and external ophthalmic and ciliary arteries. The vessels were isolated with the optic nerve, and perfused independently with Tyrode solution under a constant flow rate at 37 degrees C and a perfusion pressure of 40-80 mmHg. Drugs used were 5-hydroxytryptamine (5-HT), epinephrine (EPI), norepinephrine (NE), phenylephrine (PHE), prostaglandin F2 alpha (PGF2 alpha), ATP, dopamine (DA), tyramine (TYR), KCl, xylazine (XYL) and clonidine (CLO). Each drug solution was administered by a microinjector into the endothelial side of an artery through a cannula. Responses were obtained as changes in perfusion pressure. Results were as follows: 1) The rank order of potency for inducing a vasoconstriction in external ophthalmic arteries (EOA) was 5-HT greater than or equal to EPI greater than NE greater than PHE much greater than ATP greater than or equal to DA greater than KCl much much greater than TYR, XYL, CLO. Since PGF2 alpha induced only a slight vasoconstriction, it was omitted from the order. 2) In internal ophthalmic arteries (IOA), the responses were similar to those in EOA, although EPI, NE and PHE induced a relatively smaller response. The order was 5-HT greater than EPI = NE greater than PHE much greater than DA = ATP greater than KCl much much greater than TYR, XYL, CLO. 3) In ciliary arteries, the order was EPI greater than NE greater than PHE greater than PGF2 alpha greater than DA greater than ATP greater than KCl much much greater than TYR, XYL, CLO. It was found that 5-HT induced a slight vasoconstriction and the efficacy was low. PGF2 alpha induced a greater response in ciliary arteries than in EOA or IOA. 4) In all three arteries, alpha-2 adrenoceptor agonists, XYL and CLO did not produce significant changes in perfusion pressure. These three arteries might be rich in alpha-1 adrenoceptors but poor in alpha-2 adrenoceptors. 相似文献
26.
S Kawamura Y Sakata Y Chiba Y Yoshida T Kanazawa S Kawazu M Tsuge K Tanabe H Nara M Aizawa 《The Japanese journal of antibiotics》1986,39(5):1250-1258
Clinical evaluation of cefmenoxime (CMX, Bestcall) was performed against infections associated with hematological, respiratory tract and other disorders. Clinical effectiveness of CMX against severe infections with hematological disorders including sepsis, pneumonia, pyelitis and so on was 74.4% for good responses and against the respiratory tract infections, 96.2% for good responses was obtained. Neither objective or subjective side effects nor extreme abnormalities in laboratory tests were observed in these patients. It can be concluded, therefore, that CMX is one of the most useful drugs against infectious diseases associated with hematological disorders, respiratory tract and other disorders. 相似文献
27.
Inhibition of erythrocyte 5-aminolaevulinate hydrolase activity by tin and its prevention by selenite.
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Mice were injected with either SnCl2 (intraperitoneal) or Na2SeO3 (subcutaneous) alone or together at doses of 50 mumol/kg body weight. After 20 hours blood was collected and the concentrations of tin (Sn) and Selenium (Se) and the activity of 5-aminolaevulinate hydrolyase (ALA dehydratase, EC 4.2.1.24) in blood were determined. The concentrations of Sn in whole blood were 4.9 (SD 1.5) nmol/ml (n = 4) and ALA dehydratase activity was 10% of the control in Sn treated animals. Concentrations of Sn were 2.6 (SD 0.6) nmol/ml and ALA dehydratase activity was 92% of that in control animals when Sn and Se were simultaneously injected. The supernatant from lysed erythrocytes from Sn treated mice were applied to a Sephacryl S-300 column. The predominant peak containing Sn was eluted at the position of haemoglobin; a second peak was eluted at the position of ALA dehydratase. When the supernatant of lysed erythrocytes from mice injected with Sn and Se was chromatographed, a negligible amount of Sn was detected in the ALA dehydratase fraction. It thus appears that Sn binds to ALA dehydratase molecules and inhibits enzyme activity, and that simultaneous injection of Se prevents Sn binding to ALA dehydratase, thereby preventing the inhibition of ALA dehydratase activity by Sn. 相似文献
28.
29.
T Yokoyama H Kaneko S Kawamura M Tanaka T Chiba M Hiura S Moriwaki 《Gan no rinsho》1987,33(8):975-980
A case of a cervical cancer in a 40-year-old woman with a plasma carcinoembryonic antigen (CEA) level of 29.4 ng/ml was investigated using light and electron microscopy. In addition, the plasma CEA levels before treatment were determined in 168 patients with cervical cancer and in 33 patients with endometrial cancer. CEA was found to be elevated in the plasma of 19% of those with cervical cancer and in 6% of those with endometrial cancer. Effective serial plasma CEA determinations following therapy, in patients whose plasma or tumors initially contain elevated amounts of antigen, might be useful as an adjunctive method in the earlier detection of a recurrent cancer. 相似文献
30.
Effects of ketanserin on the pacemaker activity and atrial contractility and on 5-hydroxytryptamine (5-HT)-induced cardiac responses were investigated in the isolated, blood-perfused dog atrium. Ketanserin (1-300 micrograms) injected into the sinus node artery evoked a transient positive followed by a negative chronotropic effect, and a dose above 30 micrograms of ketanserin produced a dose-dependent negative inotropic effect with a little positive one. Ketanserin-induced negative chronotropic and inotropic effects were not affected by atropine in a dose which blocked ACh-induced responses. Propranolol inhibited positive inotropic responses to ketanserin and norepinephrine and significantly augmented the negative chronotropic and inotropic responses to ketanserin. Imipramine did not affect the transient positive followed by negative chronotropic and the negative inotropic responses to ketanserin but it induced the positive cardiac responses following the negative ones. Tetrodotoxin, phentolamine, and diphenhydramine did not modify the effects of ketanserin. From these results, it is concluded that ketanserin might induce the direct negative chronotropic and inotropic effects and the indirect effects by catecholamine release. Ketanserin-induced catecholamine release might not be due to tyramine-like or nicotine-like action. Ketanserin significantly inhibited a low dose (3 micrograms) of 5-HT-induced negative chronotropic and inotropic effects, suggesting the possibility of 5-HT2 receptors in the isolated dog atrium. 相似文献