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71.
In vitro antibacterial activity of 30 beta-lactam antibiotics including 2 beta-lactamase inhibitors (clavulanic acid and sulbactam) against 2 major pathogenic Nocardia, i.e. Nocardia asteroides group and Nocardia brasiliensis was studied. Among the antibiotics tested, a newly developed carbapenem antibiotic, imipenem (IPM), was found to be the most active, followed by oxacephem group antibiotic flomoxef (FMOX). IPM exhibited activity against only N. asteroides group (N. asteroides, Nocardia farcinica and Nocardia nova). On the other hand, FMOX showed activity against all pathogenic Nocardia tested. A 2- to 30-fold decreases in minimum inhibitory concentration (MIC) for N. asteroides, N. brasiliensis and N. farcinica was noted when antibiotics and beta-lactamase inhibitors were combined compared to antibiotics alone. Further combination and enzymatic studies indicated that all pathogenic Nocardia possess beta-lactamase except for a half of the strains of N. nova. These species' specific sensitivity patterns of pathogenic Nocardia are discussed in this paper with references to their taxonomic positions.  相似文献   
72.
A 65-year-old woman presented with an episode of hematemesis and a recurrent cervical goiter due to Graves' disease. The angiogram revealed bleeding esophageal varices which had developed through a drainage vein of the vascular goiter. Total thyroidectomy resulted in eradication of the esophageal varices.  相似文献   
73.
An antiemetic combination of methylprednisolone and droperidol was administered to 10 patients with breast cancer showing postoperative recurrence, receiving high-dose adriamycin. Methylprednisolone was given twice intravenously at a dose of 500 mg, before and after administration of adriamycin, and droperidol was given just before administration of adriamycin. The 10 patients received a total of 20 chemotherapy courses. Complete relief of vomiting was achieved in 95% of these 20 courses, and mild nausea occurred in 40%. Side effects were drowsiness, acne and akathisia, which were minimal. It was concluded that an antiemetic combination of methylprednisolone and droperidol was very effective for prevention of high-dose adriamycin-induced nausea and vomiting.  相似文献   
74.
Left ventricular function of alcoholic cardiomyopathy with congestive heart failure was investigated by echocardiography during total abstinence for six months. In five of 13 cases, left ventricular ejection fraction (LVEF) was normalized to 55% or more and left ventricular end-diastolic dimension (LVEDd) was reduced to 5.7 cm or less during the study. In the remaining eight patients, no improvement was observed. In the responsive group, two patients showed an increase of LVEF and a reduction of LVEDd simultaneously, but three showed an earlier change in LVEDd. This normalization of LVEF and LVEDd was recognized from three to 12 weeks after abstinence. No significant differences were detected between the responsive and non-responsive groups concerning their age, daily intake of alcohol and period of drinking, NYHA cardiac functional class, the period of experiencing cardiac symptoms and the cardiothoracic ratio by chest radiography. The ratio of left ventricular radius to wall thickness (R/Th) remained 2.9 or less in all of the responsive group, but seven of eight in the non-responsive group showed 2.9 or more. Left atrial dimension was reduced to the normal range except in one, but its normalization did not correlate with the change of left ventricular function. Consequently, after total abstinence from alcohol intake, both left ventricular end-diastolic dimension and ejection fraction improved rapidly, and their normalization could be highly expected. Echocardiography is very helpful in predicting the effect of total abstinence on left ventricular function in alcoholic cardiomyopathy.  相似文献   
75.
76.
The contents of catecholamines and their metabolites were measured in the adrenals of 3 groups of suncus. The first group was naive housed suncus; the second, suncus with stress-loading; and the third, wild ones. There were no significant differences in dopamine, norepinephrine and normetanephrine levels among the control, stress and wild groups. The content of epinephrine, however, decreased in the stress and wild group to 57% and 18%, respectively. These results suggest that housed suncus can easily react to stressful circumstances.  相似文献   
77.
78.
Saframycin A is an antitumor antibiotic produced by Streptomyces lavendulae 314 which falls into the category of the N-heterocyclic quinone group. Biosynthetically the quinone ring is derived from two tyrosine molecules which condense to generate the basic ring system of saframycin A. The side chain also has been found to derive from two amino acids, i.e., glycine and alanine. Supplementation by various amino acid analogs of the side chain produced three new saframycin derivatives with a replaced side chain. These three saframycins, designated Yd-1, Yd-2, and Y3, contained 2-amino-n-butyric acid, glycine, and alanine residues, respectively. in place of the normal N-terminal pyruvic acid in the side chain of saframycin A. Feeding experiments with 13C-labeled dipeptide indicated that the amino acids are probably incorporated in the side chain as a dipeptide unit. It was also found that saframycin A is produced from saframycin Y3 by an enzymatic deamination reaction. Based on these results, saframycin biosynthesis in S. lavendulae is discussed.  相似文献   
79.
BACKGROUND AND STUDY AIMS: Gastrointestinal endoscopy is an invasive examination. The aims of this study were to elucidate the effects and risks of upper gastrointestinal endoscopy with regard to cardiopulmonary functions in patients with heart disease, and to establish safety guidelines for use during endoscopy in this particular group of patients. PATIENTS AND METHODS: The patients involved were 53 inpatients in whom upper gastrointestinal endoscopy was carried out before cardiac surgery. Their cardiac functions had been evaluated previously. Electrocardiography with two leads (II, V5) was used, and blood pressure and peripheral oxygen saturation (SpO2) were monitored throughout the procedure. The relationship between the changes in cardiopulmonary parameters during endoscopy and the cardiac functions was analyzed. RESULTS: Heart rate increased immediately after insertion of the endoscope (P < 0.01). There was a significantly higher incidence of ventricular and supraventricular extrasystoles during observation of the second portion of the duodenum (P < 0.05). A lower cardiac index (P < 0.05) and a higher New York Heart Association (NYHA) functional classification (P < 0.05) were found in patients with oxygen desaturation than in patients without it. Two patients with severe coronary artery lesions showed marked ST-T depression, and these ischemic changes were thought to be due to increase in cardiac work during endoscopy. CONCLUSIONS: Upper gastrointestinal endoscopy has many adverse effects on cardiopulmonary functions in patients with heart disease. In our study, the clinical value of very close monitoring and administration of oxygen for patients with heart disease was confirmed by objective data.  相似文献   
80.
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