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A diffusion cell with an artificial membrane and the single-pass perfused rabbit ear were used to evaluate the percutaneous absorption of clonazepam from various 2-hydroxyethyl acetate (HEA) patches. The influence on drug permeation of the various type of enhancers (isopropylmyristate, lauryl alcohol, propylene glycol and water) in the patches was tested. A comparison between the two types of systems of percutaneous absorption of clonazepam has been done. The results showed that HEA patches produce controlled uniform drug release, modulated by the addition of enhancers.  相似文献   
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BACKGROUND: Laparoscopic cholecystectomy (LC) has become firmly established as a procedure of choice for gallstone disease. The procedure usually necessitates general anaesthesia and endotracheal intubation to prevent aspiration and respiratory embarrassment secondary to the induction of pneumoperitoneum. There is a paucity of data in the literature on the procedure being performed under regional (epidural) anaesthesia, especially in patients with coexisting pulmonary disease and pregnancy, who are deemed high risk for general anaesthesia. We report our preliminary experience with LC using epidural anaesthesia in patients with chronic obstructive pulmonary disease (COPD). METHODS: We performed LC in six patients (one man and five women), with a median age of 56 years (range, 38-74), under epidural anaesthesia over an 8-month period. All patients were ASA grade III/IV and the mean FEB1/FVC was 0.52 (range, 0.4-0.68), due to chronic asthma (two cases) and COPD (four cases). They were admitted a day prior to surgery for pulmonary function tests, nebulisers, and chest physiotherapy. An epidural catheter was introduced at T10/11 intervertebral space, and a bolus of 0.5% Bupivacaine was administered. Depending on the patient's pain threshold and the segmental level of analgesia achieved, incremental doses of 2 ml of 0.5% Bupivacaine along with boluses of intravenous 100 mcg Alfentanil was given to each patient. The patients were breathing spontaneously. No nasogastric tube was inserted, and a low-pressure (10 mmHg) pneumoperitoneum was created. LC was performed according to the standard technique. RESULTS: All the patients tolerated the procedure well and made an uneventful postoperative recovery. Median operating time was 50 min; average length of hospital stay was 2.5 days (range, 2-4). The epidural catheter was removed the morning after the operation. Only one patient required postoperative opioid analgesia. Two patients complained of persistent shoulder tip pain during surgery and required intraoperative analgesia (Alfentanil). There was no change in the patient's cardiorespiratory status, including PO2 and pCO2, and no complications occurred either intra- or postoperatively. CONCLUSIONS: LC can be performed safely under epidural anaesthesia in patients with severe COPD. Intraoperative shoulder tip or abdominal pain does not seem to be a major deterrent and can be effectively controlled with small doses of opioid analgesia.  相似文献   
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The circadian pattern of hemocoagulation was studied in patients with decompensated rheumatic heart disease (DRHD) concurrent with stages I-II circulatory failure (CF) during complex treatment or medical treatment with disaggregants. Biorhythmological studies demonstrated that in patients with DRHD and CF chronotherapy with curantyl had some advantages over the traditional therapy during complex drug therapy. In these patients, the chronopatterns of circadian rhythms of hemocoagulative parameters tended to normalize under the influence of curantyl chronotherapy, by diminishing the signs of external desynchronization. Advantages of chronotherapy over the traditional treatment found in patients with DRHD and stages I-II CF, as manifested by its clinical effect in shorter periods (on days 4-5) when small daily and course doses of the drug were used. Based on the biorhythmological studies of hemostatic parameters, a method of curantyl chronotherapy was developed for patients with DRHD and stages I-II CF, which may optimize the therapeutical process in patients with this abnormality.  相似文献   
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Renal elimination of the bromosulfophthalein-glutathione conjugate (BSP-GSH) after its i.v. administration in the rat in vivo is negligible. In our study we wanted to establish whether the high albumin-binding of BSP-GSH constitutes the major restrictive factor toward the urinary excretion of the compound. The renal disposition of BSP-GSH was studied in the isolated rat kidney during perfusions with or without albumin in the perfusate. The urinary clearance of BSP-GSH in the absence of albumin was very low (< 60 microliters/min) as compared to the inulin clearance (approximately 300 microliters/min). This indicates that albumin-binding is not the major reason for the low urinary clearance of BSP-GSH. Addition of albumin to the perfusate further decreased the urinary excretion by 60%. BSP-GSH is metabolized by the kidney into two major metabolites: the cysteinylglycine conjugate and the di-glutathione conjugate. Both metabolites appear in perfusate, which suggests that BSP-GSH undergoes tubular (re-)uptake. The di-glutathione conjugate is further metabolized to the di-cysteinylglycine conjugate. The di-glutathione conjugate and the di-cysteinylglycine conjugate are the major urinary components and the urinary elimination of BSP-GSH may depend on their formation. Inhibition of gamma-glutamyl transpeptidase activity with acivicin largely prevented the degradation to the cysteinylglycine and dicysteinylglycine conjugates of BSP. The total rate of urinary excretion, however, was only slightly lowered by acivicin. Apparently, cleavage of the gamma-glutamyl moiety is not relevant for the total urinary elimination of BSP-GSH.  相似文献   
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Mechanisms of drug resistance in Campylobacter jejuni were investigated. Mutant strains 34PEFr, which was resistant to pefloxacin (128-fold increase in the MIC), and 34CTXr, which was resistant to cefotaxime (32-fold increase in the MIC) and which was derived from the susceptible parent 34s, were obtained by serial passages on pefloxacin and cefotaxime gradient plates, respectively. Both mutants showed cross-resistance to erythromycin, chloramphenicol, tetracycline, beta-lactams, and quinolones. While the quinolone resistance of strain PEFr could be explained by a mutation at codon 86 of the gyrA gene, the multidrug resistance phenotype of both strains was further investigated. Accumulation of pefloxacin, ciprofloxacin, and minocycline was measured by fluorometry and was found to be lower in the mutant strains than in the parent strain. Preincubation of the cells with carbonyl cyanide m-chlorophenylhydrazone, however, completely abolished this difference. Analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of outer membrane preparations from both mutant strains showed overexpression of two proteins of 55 and 39 kDa which were absent from the outer membranes of the wild-type strain. These results indicate that in C. jejuni 34PEFr and 34CTXr, multidrug resistance is associated with an efflux system with a broad specificity.  相似文献   
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