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991.
WARHEIT DAVID B.; KELLY DAVID P.; CARAKOSTAS MICHAEL C.; SINGER ALLEN W. 《Toxicological sciences》1989,12(2):333-345
A 90-Day Inhalation Toxiaty Study with Benomyl in Rats. WARHEIT,D. B., KELLY, D. P., CARAKOSTAS, M. C., AND SINGER, A. W. (1989).Fundam Appl Toxicol./ 12, 333-345. Benomyl [methyl 1-(butylcarbamoyl)-2-benzimidazolecarbamate,CAS Registry No. 17804-35-2] is a fungicide and the possibilityfor inhalation exposure exists for field workers. To assessthe toxicity of benomyl, groups of 20 male and 20 female CDrats were exposed nose-only 6 hr a day, 5 days a week, to concentrationsof 0, 10, 50 or 200 mg/m3 of a benomyl atmosphere. At the midpoint(approximately 45 days on test) and at the end of the exposureperiod, blood and urine samples for clinical evaluation werecollected from 10 rats/group/sex, and these animals were sacrificedfor pathological examination. Similar evaluations were performadon all remaining rats at the end of the 90-day test period.After approximately 45 days on test, compoundrelated degenerationof the olfactory epithelium was observed in all males and in8 of 10 female rats exposed to 200 mg/m3 benomyl. Two male ratsexposed to 50 mg/m3 had similar, although less severe, areasof olfactory epithelial degeneration. After approximately 90days of exposure, the remaining 10 rats/group/sex were sacrificedand examined. Of these rats, all of the males and females exposedto 200 mg/m3 had olfactory degeneration, along with 3 malesexposed to 50 mg/m3 of benomyl. No other observed lesions wereinterpreted to have been caused by the benomyl exposure. Inaddition, male rats exposed to 200 mg/m3 benomyl had depressedmean body weights compared to controls and this finding correlatedwith a reduction in food consumption. Based on pathologicalobservations, 10 mg/m3 represents the no-observable-effect level(NOEL) for the male rats, and 50 mg/m3 is the NOEL for the femalerats. 相似文献
992.
Edward T. Crosby Stephen H. Halpern Stephen H. Rolbin 《Journal canadien d'anesthésie》1989,36(6):701-704
The safety of epidural anaesthesia in patients with active, recurrent genital herpes simplex (HSV) infections is controversial. We reviewed the six-year experience of the use of epidural anaesthesia in this patient population in two institutions. Eighty-nine parturients with active genital HSV were administered epidural anaesthesia for Caesarean section. No patient suffered an adverse outcome related to either the anaesthetic or the virus. The theoretical risks of regional anaesthesia in the parturient with active herpes genitalis are reviewed. We conclude from available data that the risk of an adverse outcome is small and does not contraindicate the use of epidural anaesthesia in patients with recurrent infection. 相似文献
993.
Enantiomeric interaction of flurbiprofen in the rat 总被引:2,自引:0,他引:2
Flurbiprofen [FL, (+/-)-2-(2-fluoro-4-biphenylyl)propionic acid] is a 2-arylpropionic acid nonsteroidal anti-inflammatory drug which is commercially available as a racemate. The anti-inflammatory activity of FL, however, appears to be mainly due to the S enantiomer. Recently, it has been postulated that, in both humans and rats, the two enantiomers of FL may interact when racemic doses are given. This study examines the above postulate in the rat by administration of single iv doses of racemic FL (10 mg/kg), and R- and S-FL (5 mg/kg of each). Plasma concentrations (0-12 h) of the enantiomers were measured using a stereospecific HPLC assay. A significant interaction was noticed between the enantiomers: mean AUC +/- SD of R-FL was reduced from 115.3 +/- 21.3 to 49.0 +/- 10.4 mg/L.h as a result of S-FL coadministration. A trend towards reduced S-FL plasma concentration was also evident when the enantiomer was given as the racemate [mean AUC +/- SD; 176.8 +/- 37.7 racemate versus 241.4 +/- 86.2 mg/L.h alone]. The reduction in S-FL, however, was not significant due perhaps to the observed interanimal variation. While the enantiomeric interaction caused a significant enlargement of the volume of distribution of R-FL, it failed to alter the terminal half-life of the enantiomer. It is suggested that the interaction is a result of displacement from plasma protein binding sites of one enantiomer by the other. 相似文献
994.
995.
996.
K Tsuiki I Ohta N Oh-hara T Kaminishi M Oguma S Yasui 《Journal of cardiovascular pharmacology》1989,14(2):268-277
Effect of intracoronary infusion of diltiazem (1 microgram/min) on regional myocardial blood flow (RMBF) was studied using 15-microns radioactive microspheres in 11 excised cross-circulated canine left ventricles. With total coronary blood flow (CBF) and heart rate (HR) held constant, regional ischemia was induced by ligating the left anterior descending coronary artery (LAD). Diltiazem at the dose used had no effects on ventricular Emax before and after LAD ligation. RMBF expressed by the counts divided by the counts averaged in all segments in each layer significantly (p less than 0.05) increased under diltiazem only in the low-flow region that had less than 50% RMBF before diltiazem; from 21% (+/- 12%) to 35% (+/- 18%) in the epicardial, from 22% (+/- 12%) to 32% (+/- 18%) in the midwall, and from 24% (+/- 10%) to 31% (+/- 12%) in the endocardial layers. We conclude that the beneficial effect of diltiazem on the ischemic heart involves a direct action on the coronary vascular system and does not necessarily depend on the concomitant changes in hemodynamics. 相似文献
997.
Clinical pharmacokinetics-pharmacodynamics of anticancer drugs 总被引:3,自引:0,他引:3
998.
A case of chronic subdural hematoma with anxiety states and concomitant regression-like symptoms 总被引:1,自引:0,他引:1
The authors described an epileptic suffering from head trauma in whom anxiety states and concomitant regression-like symptoms masked the diagnosis of chronic subdural hematoma. Along with the occurrence of chronic subdural hematoma, psychic symptoms were manifested including the anxiety and regression of personality. However, after the chronic subdural hematoma was neurosurgically evacuated, these psychic symptoms gradually disappeared. In the study of organic and symptomatic psychosis, Mackenzie and Popkin (1983) have proposed the concept of an organic anxiety syndrome on the ground that DSM-III provides no organic equivalent for anxiety disorders. Therefore, we presented a case of chronic subdural hematoma in which the direct effect on CNS of this pathological condition was considered to bring about the above-mentioned anxiety disorders with regression-like symptoms. 相似文献
999.
H Ogura H Kubota I Nomura T Tomoda K Araki Y Ogura T Kurashige 《The Japanese journal of antibiotics》1989,42(2):401-410
A new macrolide antibiotic, clarithromycin (TE-031, A-56268), was studied for its clinical efficacy in the field of pediatrics. Patients treated were infants and children ranging from 2 months to 11 years old suffering from acute bronchitis in 5 cases, acute tonsillitis in 2 cases, Mycoplasma pneumonia in 2 cases, pertussis in 6 cases, scarlatina in 1 case and acute enteritis in 2 cases, a total of 18 cases. TE-031 was administered 19.7-43.5 mg/kg in daily doses and lengths of treatment ranged from 4 to 19 days. As regards to its clinical efficacy, good or excellent results were obtained in all cases: excellent in 11 cases and good in 7 cases. No clinical side effects nor abnormal laboratory test values obviously attributable to TE-031 were observed. 相似文献
1000.
Optic nerve glioma and the management of optic nerve tumours in the young. 总被引:4,自引:0,他引:4 下载免费PDF全文
Thirty-one patients presenting as orbital optic nerve glioma have been reviewed with maximum follow-up of 14 years. Sixteen of these patients have been reported on previously and further follow-up is provided. Sixteen patients had a stable clinical course with little change over a period of up to 13.5 years. Neurofibromatosis was relatively common in this group (11/16). Fifteen patients had progressive enlargement of the tumour; the incidence of neurofibromatosis in this group was low (4/15). Eleven of these patients were explored neurosurgically and the optic nerve totally excised in 10 of them. The proximal cut end was normal in six patients and the chiasm has apparently remained free of tumour in all of them. We suggest a method of management of primary optic nerve tumours, both meningiomas and gliomas, in young patients. 相似文献