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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Lack of effect of the calcium antagonist isradipine on cyclosporine pharmacokinetics in renal transplant patients. 总被引:1,自引:0,他引:1
L Endresen S Bergan H Holdaas T Pran B Sinding-Larsen K J Berg 《Therapeutic drug monitoring》1991,13(6):490-495
Hypertension has emerged as a frequent side effect in transplant recipients on effective doses of cyclosporine (CsA). To control hypertension in renal transplant patients, calcium channel blockers have been used; some of these, however, have been shown to cause significant increases in CsA levels. These findings point out that possible interactions of each calcium antagonist with CsA deserve investigation. We performed an open, placebo-controlled study in 12 stable renal transplant recipients to determine whether short-term isradipine influences CsA pharmacokinetics. All patients had mild to moderate hypertension and received triple immunosuppressive therapy with CsA, azathioprine, and prednisolone. Throughout a 4-week period of isradipine treatment, blood CsA levels (specific and nonspecific monoclonal antibodies) remained stable. The mean trough specific level was 121 +/- 14 micrograms/L following placebo, compared to 120 +/- 14 micrograms/L during isradipine. Corresponding non-specific values were 465 +/- 68 and 474 +/- 63 micrograms/L. Also, values for Cmax, AUC, and t1/2 were not significantly changed following 4 weeks of isradipine. Mean arterial pressure was significantly reduced at the end of the study. This study implies that isradipine does not influence CsA metabolism. Further studies should be carried out to determine its long-term effects on CsA pharmacokinetics and renal function in transplanted patients. 相似文献
992.
When human divers and experimental animals are exposed to an increasing environmental pressure, they develop the high pressure neurological syndrome (HPNS) characterized by electroencephalographic changes and sleep and behavioral disturbances. In rats, behavioral disturbances essentially include hyperlocomotor activity (HLA), tremor and myoclonia. Moreover, HLA has recently been demonstrated to be linked to a pressure-induced striatal increase of dopamine (DA). In these experiments, it was proposed to investigate in rats, at the behavioral level, the role of DA receptors in the occurrence of the pressure-induced DA disturbances. DA receptor agonists were found to induce no significant changes in the development of HLA, tremor, and myoclonia. Alternatively, HLA was found to be dramatically antagonized by the use of DA receptor antagonists (SCH 23390, sulpiride, and haloperidol), while tremor and myoclonia only decreased in SCH 23390 experiments. 相似文献
993.
994.
R Menningen M Günther N B?nninghoff C D Stahlknecht I Kubitza J Kusche 《Agents and actions》1986,18(1-2):38-40
In the operative treatment of appendicitis the so called negative appendectomy is an important issue because of its increased morbidity. From the hypothesis that the intestinal diamine oxidase activity is a suitable marker of mucosal integrity, the distribution pattern of the enzyme in appendices histologically classified as inflamed or not inflamed was studied. Histologically apparent inflammation of the appendix was connected with a significant reduction of diamine oxidase activity. The determination of this enzymic activity may be a simple and sensitive test for mucosal inflammation of the appendix even at a very early state. This could reduce the rate of negative appendectomies and influence thereby risk-cost-benefit calculations. 相似文献
995.
Gestational age determination based on obstetric dating criteria, early pregnancy ultrasound scans, Dubowitz examinations, and ultrasound scans performed shortly before delivery were reviewed for 69 preterm infants requiring neonatal intensive care. The last ultrasound scans underestimated gestational age by a median of 8 days, and by 2 weeks or more in 20 of the 69 cases, as opposed to best dating criteria. Ultrasonic fetal weight estimation was more accurate, but erred by more than 20% in 10% of cases. When obstetric decisions regarding preterm neonates must be made without prior information regarding gestational age, late ultrasound findings must be applied with extreme care. 相似文献
996.
Alan Willmore Tim Sladden Lucy Bates Craig B Dalton 《International journal of health geographics》2006,5(1):30-14
Background
To determine patterns of childhood lead exposure in a community living near a lead and zinc smelter in North Lake Macquarie, Australia between 1991 and 2002. 相似文献997.
998.
D. M. Reid I. Mackay S. Wilkinson C. Miller D. G. Schuette J. Compston C. Cooper E. Duncan N. Galwey R. Keen B. Langdahl A. McLellan H. Pols A. Uitterlinden J. O’Riordan J. A. H. Wass S. H. Ralston S. T. Bennett 《Osteoporosis international》2006,17(1):125-132
Osteoporosis is a common disease with a strong genetic component characterized by reduced bone mass and an increased risk of fragility fractures. Bone mineral density (BMD) is the most important determinant of osteoporotic fracture risk, but the genes responsible for BMD regulation and fracture are incompletely defined. To enable multi-center studies to examine the genetic influences on BMD there is a requirement to standardize measurements across different manufacturers of bone densitometers, different versions of machines and different normative ranges. This paper describes a method developed to allow near-identical subjects with low age-adjusted BMD (based on Z-scores) to be recruited in 17 centers using 27 different densitometers. Cross-calibration was based on measurements using a European spine phantom circulated to all centers and measured ten times on each individual machine. From theses values an individual exponential curve, based on nominal versus observed BMD, was derived for each machine. As expected, there were large and significant variations in nominal BMD values, not only between scanners from different manufacturers but also between different versions of scanners from the same manufacturer. Hologic scanners tended to underestimate the nominal BMD, while Lunar scanners overestimated the value. Norland scanners gave mixed values over estimating BMD at the lower nominal value (0.5 g/cm2) while underestimating the value at the higher value (1.5 g/cm2). The validity of the exponential equations was tested using hip and spine measurements on 991 non-proband women from a familial osteoporosis study (FAMOS). After cross-calibration there was a considerable reduction in variation between machines. This observation, coupled with the absence of a similar reduction in variation attributable to a linear regression on age, demonstrated the validity of the cross-calibration approach. Use of the cross-calibration curves along with a standard normative range (in the case of this study, the Hologic normative range) allowed age-specific Z-scores to be used as an inclusion criterion in this genetic study, a method that will be useful for other trials where age-specific BMD inclusion criteria are required. 相似文献
999.
Signe S?nderkaer Marianne Schmiegelow Henrik Carstensen Lars B?geskov Nielsen J?rn Müller Kjeld Schmiegelow 《Journal of clinical oncology》2003,21(7):1347-1351
PURPOSE: To evaluate the pattern of neurological late effects in patients who have received surgery only for a brain tumor in childhood and to identify possible risk factors for neurological sequelae. PATIENTS AND METHODS: The medical, histologic, and operative records were reviewed for 65 consecutive patients operated for a benign brain tumor from 1970 to 1997, and all patients were re-examined after a median length of follow-up of 10.7 years. Thirty-four patients had posterior fossa tumors, 22 patients had cerebral hemisphere tumors, and nine patients had midline tumors. RESULTS: At the time of follow-up, 20 patients (31%) had no neurological deficits, 22 patients (34%) had minor deficits that did not interfere with their daily life activities, and 23 patients (35%) had moderate or severe deficits such as severe ataxia, spastic paresis, seriously reduced vision, or epilepsy with more than two seizures per year. Fourteen of the 31 patients (45%) registered with ataxia preoperatively had recovered fully. Six of seven patients had persistence of a pre- or postoperatively developed hemiparesis. Thirteen of 23 patients had persistence of cranial nerve deficits that developed second to surgery. Fifty-five percent of the 18 patients with seizures at diagnosis were seizure-free at follow-up. At follow-up both ataxia and hemiparesis were significantly more frequent among females (P =.02 and P =.03, respectively). CONCLUSION: In patients who received operation as the only treatment for their brain tumor, there was a good chance of total or partial recovery of preoperative and postoperative neurological deficits, although only one third of the patients will have no long-term neurological deficits. 相似文献
1000.
Maximum anchorage often presents a problem that is difficult to solve during orthodontic tooth movement. Stationary, skeletal anchorage can be achieved in a simple, minimally-invasive manner, and unwanted tooth movements in opposite directions can be prevented by using transmucosally-inserted bone screws.Our initial experience using the FAMI screw as an orthodontic micro-implant proved to be clinically and histologically successful. 相似文献