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991.
992.
SG Chrysant H Gavras AL Niederman TC Marbury R Goldstein 《Canadian Metallurgical Quarterly》1997,37(9):810-815
The use of angiotensin converting enzyme inhibitors and calcium channel blockers, as monotherapies and in combination, is common in the management of hypertension. Clinical studies have documented the augmentation of blood pressure reduction when these agents are combined compared with the individual agents, in short-term studies. In the present investigation, 93 patients with stage 3-4 essential hypertension, who successfully completed a short-term double-blind study, participated in a 40-week open-label treatment phase. The patients were maintained on their previous doses of enalapril/diltiazem ER (E/D) with or without additional antihypertensive medications. Doses of medication could be adjusted as necessary for blood pressure control. Of the 93 patients, 68% were male and 82% were white; they averaged 52.7 years of age and had a baseline mean sitting blood pressure (SiBP) of 167/111 mmHg. The use of E/D alone (n = 14) reduced mean SiBP by 14.5/14.4 mmHg from baseline, whereas the use of E/ D with other agents (n = 79) decreased it by 27/20.5 mmHg from baseline. E/D alone or in combination with other drugs was well-tolerated, and no serious adverse events were noted. This long-term open-label study demonstrated that the E/D combination alone or with the addition of other antihypertensive drugs was effective, safe, and well-tolerated after prolonged administration. 相似文献
993.
JL Lopez-Ribot RK McAtee LN Lee WR Kirkpatrick TC White D Sanglard TF Patterson 《Canadian Metallurgical Quarterly》1998,42(11):2932-2937
Resistance to fluconazole is becoming an increasing problem in the management of oropharyngeal candidiasis in human immunodeficiency virus-infected patients. Strains obtained from five patients developed decreased fluconazole susceptibility over time. DNA strain typing confirmed the high degree of relatedness among isolates from one patient and the variability among isolates from different patients. Expression of genes involved in development of fluconazole resistance was monitored in each isolate using probes specific for ERG11 (lanosterol 14alpha-demethylase), MDR1 (a major facilitator), and CDR (ATP-binding cassette or ABC transporter) genes. Increased expression of CDR genes was detected in the series of isolates from two patients. Isolates from one of the two patients also demonstrated increased ERG11 expression, whereas isolates from the other patient did not. Increased levels of MDR1 mRNA correlated with increased resistance in sequential isolates from another patient. Initial overexpression of MDR1 with subsequent overexpression of CDR genes and a final isolate again overexpressing MDR1 were detected in serial isolates from another patient. In another patient, overexpression of these genes was not detected despite an eightfold increase in fluconazole MIC. In this patient, sequence data of the ERG11 gene revealed no point mutations associated with decreased susceptibility. Five different patterns of gene expression were observed in isolates recovered from five patients who developed resistance. Therefore, these experiments demonstrate that a variety of mechanisms or combinations of mechanisms are associated with the development of fluconazole drug resistance. Additional studies are needed to estimate the frequency and clinical impact of these mechanisms of resistance. 相似文献
994.
995.
YF Ngeow AF Weil NS Khairullah MY Yusof L Luam C Gaydos TC Quinn 《Canadian Metallurgical Quarterly》1997,33(5):422-425
OBJECTIVE: The incidence of Chlamydia pneumoniae and Chlamydia trachomatis infection was studied among infants and young children admitted to hospital for the management of lower respiratory tract infections, over a 12 month period. METHODOLOGY: Respiratory secretions were examined for chlamydiae by cell culture, enzyme-linked immunosorbent assay and polymerase chain reaction-enzyme immunoassay. Sera were tested by micro-immunofluorescence for chlamydial IgG, IgM and IgA. Other bacterial and viral pathogens were also looked for by standard cultural and serological methods. RESULTS: Of 87 patients aged 2 months-3 years, an aetiologic diagnosis was made in 41 (47.1%). C. pneumoniae and C. trachomatis were each detected in 1 (1.2%) of the patients. Among common bacterial pathogens, Haemophilus influenzae (13.8%) and Streptococcus pneumoniae (8.1%) were the most frequently identified. Respiratory viruses and elevated Mycoplasma pneumoniae antibodies were found in 10.3% and 9.1% of patients, respectively. CONCLUSION: Chlamydiae are infrequent causes of community-acquired acute lower respiratory tract infections in infants and very young children in Malaysia. 相似文献
996.
1. The fate of [14C]BRL 49653C, a novel thiazolidinedione antidiabetic agent, has been studied following oral administration to the rat and dog. 2. Clearance was almost exclusively by metabolism, with only small amounts of unchanged BRL 49653 being excreted by either species. 3. Phase I metabolism resulted in ring hydroxylation, N-demethylation and oxidative removal of the pyridinylamino function to yield a phenoxyacetic acid derivative. 4. Sulphation of phase I metabolites occurred in both species, but glucuronidation was only observed in the rat. 5. The parent compound was the major circulating component in both species at early times, but at later times sulphate conjugates of phase 1 metabolites were predominant. 相似文献
997.
Because of increasing reports of multiple-antibiotic-resistant strains of Streptococcus pneumoniae and associated clinical failures, this study was performed to determine the prevalence of multiresistance among strains from nine Louisiana medical centers. Using a National Committee for Laboratory Standards broth microdilution method, 481 strains were tested. Of these, 70% were penicillin-susceptible (PS), 23% had intermediate minimum inhibitory concentration values to penicillin (I), and 7% were fully resistant to penicillin (PR). The isolation rates (15% to 40% for I strains and 0% to 33% for PR strains) at the various medical centers varied appreciably. The prevalence of penicillin resistance was highest among upper respiratory isolates, while cross-resistance to other antimicrobials varied. The least cross-resistance was noted among PS strains. However, strains with reduced penicillin susceptibility had high levels of cross-resistance. Among I strains, the prevalence of cross-resistance (%) was noted for amoxicillin/clavulanate (6%), cefuroxime (71%), cefaclor (91%), ceftriaxone (13%), cefotaxime (34%), erythromycin (67%), azithromycin (32%), and clarithromycin (32%). For PR strains, the prevalence of cross-resistance was 97% for amoxicillin/clavulanate, cefuroxime, and cefaclor; 67% for ceftriaxone and erythromycin; 89% for cefotaxime; and 69% for azithromycin and clarithromycin. These data emphasize the high prevalence of multiple-antimicrobial-resistance among strains of S pneumoniae with reduced penicillin susceptibility in this geographic area. 相似文献
998.
We investigated the withdrawal of temazepam in a single general practice using two alternative prescribing policies: an alternative benzodiazepine; or an alternative group of drugs recommended for short-term management of insomnia, including sedative antihistamines and chloral hydrate. The study showed that temazepam prescribing in general practice can be reduced or stopped by using a simple intervention. An alternative benzodiazepine is useful in helping patients to stop their use of hypnotic agents. The use of antihistamines as substitute hypnotics is not advocated on the basis of our findings. 相似文献
999.
1000.
Detection of Cr(V) in the reduction of Cr(VI) by whole live mice and its characterization were carried out by low frequency electron paramagnetic resonance (EPR). Intravenous injection of Cr(VI) to mice generated Cr(V). The Cr(V) was found predominantly in the liver with a small amount in the blood. Liver homogenates from Cr(VI) treated mice generated essentially the same Cr(V) spectrum as that obtained from the whole live mice. This Cr(V) species was identified to be a Cr(V)-nicotinamide adenine dinucleotide (NAD) (P)H complex with an oxygen bond to Cr(V). Pretreatment of the mice with ascorbic acid and glutathione reduced the Cr(V) formation, while pretreatment with reduced nicotinamide adenine dinucleotide (NADH) enhanced it. Metal chelators, ethylenediaminetetraacetic acid (EDTA), 1,10-phenanthroline, and diethylenetriaminepentaacetic acid (DTPA) inhibited the intensity of the Cr(V) signal. The results suggest that Cr(V) generated in the whole body of a live animal is a Cr(V)-NAD(P)H complex and NAD(P)H/flavoenzymes and not glutathione or ascorbate as the major one-electron Cr(VI) reductant responsible for observed formation of Cr(V)-NAD(P)H complex in vivo. 相似文献