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71.
72.
This paper reviews systematic toxicological analysis (STA) procedures for acidic drugs and/or metabolites relevant to clinical and forensic toxicology or doping control using gas chromatography, gas chromatography-mass spectrometry, liquid chromatography, thin-layer chromatography and capillary electrophoresis. Papers from 1992 to 1998 have been taken into consideration. Screening procedures in biosamples (whole blood, plasma, serum, urine, vitreous humor, brain, liver or hair) of humans or animals (horse, or rat) are included for the following drug classes: angiotensin-converting enzyme (ACE) inhibitors and angiotensin II (AT-II) blockers, anticoagulants of the 4-hydroxy coumarin type, barbiturates, dihydropyridine calcium channel blockers (calcium antagonists), diuretics, hypoglycemic sulfonylureas and non-steroidal anti-inflammatory drugs (NSAIDs). Methods for confirmation of preliminary results obtained by screening procedures using immunoassay or chromatographic techniques are also included. Furthermore, procedures for the simultaneous detection of several drug classes are reviewed. The toxicological question to be answered and the consequences for the choice of an adequate method, the sample preparation and the chromatography itself are discussed. The basic information about the biosample assayed, work-up, separation column, mobile phase or separation buffer, detection mode and validation data of each procedure is summarized in 16 tables. They are arranged according to the drug class and the analytical method. Examples of typical applications are presented. Finally, STA procedures are reviewed and described allowing simultaneous screening for different (acidic) drug classes. 相似文献
73.
74.
Gabapentin, a novel antiepileptic drug, is effective in the treatment of partial seizures with and without secondary generalization. Evidence suggests that it may have mood-stabilizing and possibly antidepressant properties in bipolar depression. We report on a 48-year-old woman who had recurrent major depressive disorder. Following inguinal herniorrhaphy, she developed severe stabbing pain in the lower abdomen and inguinal area that progressed to constant pain in her whole body. She was depressive, hopeless, and had given up her social activities. A diagnosis of major depressive disorder and somatoform pain disorder was made. Antidepressants and carbamazepine were ineffective, and she had attempted suicide. Gabapentin resulted in remission of both the pain and the depressive mood at a dose of 1.800 mg/day. 相似文献
75.
Growth of human tumor cells in macroporous microcarriers results in p53-independent, decreased cisplatin sensitivity relative to monolayers 总被引:2,自引:0,他引:2
Maurer BJ Ihnat MA Morgan C Pullman J O'Brien C Johnson SW Rasey JS Cornwell MM 《Molecular pharmacology》1999,55(5):938-947
Multicellular contact has been shown to influence the in vitro sensitivity of cells to drug treatment. We investigated the use of macroporous gelatin microcarriers, CultiSpher-G, as a convenient laboratory system for the molecular analysis of this "contact effect". We determined that human A549 cells can be grown in CultiSphers with growth and cell cycle parameters similar to those of monolayers. In addition, cells in CultiSphers express less p27/kip1, an indicator of cell cycle arrest, than equivalent cells in monolayers. When treated with drugs, A549 cells grown in CultiSphers or monolayers accumulate equivalent amounts of platinum-DNA adducts and similar amounts of doxorubicin. Moreover, A549 and KB-3-1 cells in CultiSphers have significantly decreased sensitivity to cis-platinum(II)diammine dichloride (cisplatin), 4-hydroperoxycyclophosphamide, doxorubicin, and paclitaxel (taxol) compared with cells in monolayers when assayed by clonogenic survival. Cisplatin treatment in monolayers or CultiSphers did not result in apoptotic cell death. In contrast, paclitaxel caused a significant amount of sub-G1 DNA, an indicator of apoptosis, which was diminished when cells were grown in CultiSphers compared with monolayers. When grown in CultiSphers, cells with abrogated p53 function (A549/16E6 and NCI-H1299) were less sensitive to cisplatin than the corresponding monolayer cells, indicating that the decrease in sensitivity is p53 independent. Taken together, the data suggest that CultiSpher-G microcarriers are a useful in vitro system to examine the effects of three-dimensional cell contact on drug sensitivity of human tumor cells. 相似文献
76.
Thomas Dierks Stefan Barta Lothar Demisch Klaus Schmeck Ekkehart Englert Andrea Kewitz Konrad Maurer Fritz Poustka 《Psychopharmacology》1999,146(1):101-107
Rationale: The intensity dependence of the auditory evoked potentials (AEP) has been suggested to be a specific biological marker of
central serotonergic activity. Objective: While previous studies used circumstantial evidence to support this hypothesis, we manipulated (decreased) cerebral levels
of serotonin directly by using tryptophan depletion. Methods: Twelve healthy young subjects were investigated using placebo and two different amino acid mixtures in a double blind cross
over design on three different occasions. AEPs recorded during tryptophan depletion were analyzed by dipole analysis and regional
sources using methods published in the literature. Results: For none of the mixtures a significant effect of tryptophan depletion was found. There was a trend towards reduced intensity
dependency after tryptophan depletion, especially in the right hemisphere. This reduction correlated with the amount of reduced
tryptophan in plasma. Conclusions: The results indicate, in contrast to earlier indirect studies, that the intensity dependence of AEPs is not a specific marker
of central serotonergic activity.
Received: 8 March 1999 / Final version: 25 May 1999 相似文献
77.
The chromosomes of metastatic cells and polyploid levels in the bone marrow of 26 patients with small cell anaplastic carcinoma were studied by direct bone marrow preparation and trypsin-Giemsa banding. Eighteen of these patients had received no tumor therapy and 8 had had chemotherapy and/or radiation therapy; 18 patients, including 5 who had received therapy, had karyotypic abnormalities with or without elevation of the polyploid level. Modal numbers and chromosome abnormalities were highly variable in treated and untreated patients. Modes ranged from hypodiploid to polyploid, but polyploid modes were the most frequently observed abnormal modes. Polyploid modes were not seen, however, in post-therapy patients with the exception of one who had received radiation therapy to the mediastinum for only 4 days prior to withdrawal of the specimen for chromosome analysis. Ten patients had elevated polyploid levels that ranged from 4.24 to 44.8% and always occurred in conjunction with karyotypic abnormalities. Both aneusomy (abnormal number) of normal chromosomes and structural aberrations (markers) occurred frequently. Some markers were consistent within an individual, but other variable aberrations were also typically present. Very few markers were common to 2 or more patients. The no. 1 chromosome participated in marker formation in 14 of the 18 patients with karyotypic abnormalities. Of the 26 patients, 5 were negative for metastasis to the marrow by pathologic examination but positive by cytogenetic diagnosis, whereas none were positive by pathologic examination and negative by cytogenetic diagnosis; this demonstrated that cytogenetics may be used as a rapid adjunct diagnostic procedure for the detection of metastasis in the marrow. 相似文献
78.
Intraoperative color Doppler recordings, obtained either from the epicardial or transesophageal approach, offer real-time information about the presence and severity of mitral regurgitation at the time of surgery. The technique allows instantaneous evaluation of mitral and tricuspid repair and may offer important information about the postoperative outcome. 相似文献
79.
D M Hays R B Raney W Lawrence M Tefft E H Soule W M Crist M Foulkes H M Maurer 《Journal of pediatric surgery》1982,17(6):812-820
Twenty-nine children (24, male; 5, female) with non-disseminated rhabdomyosarcomas of the bladder or prostate were treated (1978-1980) by a primary chemotherapy regimen consisting of vincristine, actinomycin D, and cyclophosphamide ("Pulse" VAC), with or without local radiotherapy. During the initial 20 wk of chemotherapy, nine children achieved a Clinical Complete Response (CCR). Three of these are without evidence of disease (NED) and have functional bladders, two following partial cystectomy. Four who achieved a CCR subsequently relapsed or remained biopsy positive, but are at present NED following radiotherapy and anterior exenteration. Two patients who achieved CCR status relapsed and have died of disease. Twelve patients had a Clinical Partial Response (CPR) in less than 20 wk and two others in less than 40 wk. Seven of these are NED with intact bladders following chemotherapy-radiotherapy; and an additional patient is NED following partial cystectomy. Four patients in the CPR group have been treated by exenteration following failure to achieve complete response, and are NED. One patient has died, and one has progressive disease. Six patients had an inadequate response to chemotherapy (NR). Anterior exenteration was carried out in three, and two of these have survived. The overall results in these 29 patients are: (A) alive and disease-free with functional bladders, 11; (B) alive and disease-free following anterior exenteration, 10; and (C) dead or death from tumor anticipated, 8. The function of retained bladders (11) has been satisfactory. 相似文献
80.