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71.
Effect of dexamethasone on symptoms of acute mountain sickness at Pikes Peak, Colorado (4,300 m) 总被引:1,自引:0,他引:1
P B Rock T S Johnson A Cymerman R L Burse L J Falk C S Fulco 《Aviation, space, and environmental medicine》1987,58(7):668-672
In a previous controlled study, dexamethasone (DEX) was shown to prevent acute mountain sickness (AMS) during exposure to simulated high altitude. To determine the effect of DEX during actual altitude exposure, 16 young men were treated with either DEX (4 mg every 6 h) or placebo for 48 h prior to and 48 h after being rapidly transported from sea level to the summit of Pikes Peak, CO (4,300 m). Symptoms of AMS were evaluated twice daily at Pikes Peak using the Environmental Symptoms Questionnaire and a clinical assessment. During treatment the mean symptom scores were higher for subjects taking placebo in 18 out of 20 comparisons. On an individual basis, 60% of the subjects receiving placebo met the criteria for being "sick" compared to 31% of subjects receiving DEX. Beginning 24 h after cessation of treatment, DEX subjects experienced a progressive increase in symptom scores which lasted through the end of the altitude sojourn (day 6). The results indicate that DEX is an effective prophylactic treatment for AMS in an actual mountain environment, but that AMS symptoms can occur if the drug is stopped abruptly. 相似文献
72.
Huettig Fabian Schwendicke Falk 《Bundesgesundheitsblatt, Gesundheitsforschung, Gesundheitsschutz》2021,64(7):862-870
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - In den letzten 8 Jahren wurde in Deutschland nicht nur „mehr Versorgungsforschung in der Zahnmedizin“ gefordert,... 相似文献
73.
Shah A Krol G Sundaresan P Lettieri J Falk R Lasseter K Heller AH 《American journal of therapeutics》1995,2(1):15-19
The pharmacokinetics of a controlled-release formulation (coat--core) of the calcium channel blocker nisoldipine was investigated in eight subjects with biopsy-proved liver cirrhosis and eight healthy subjects. In Stage I, subjects received a single 10-mg dose to determine if this dose would be safely tolerated in the subjects with cirrhosis. Because all subjects in both groups tolerated the dose without difficulty, all were continued to Stage II. In Stage II, subjects received a once-daily dose of 10-mg coat-core tablets for 7 days. Serial plasma samples were assayed for nisoldipine in both stages. The C(max) and AUC of nisoldipine were approximately fourfold to fivefold higher (p < 0.01) in subjects with cirrhosis as compared to healthy subjects; however, there was overlap in the range of pharmacokinetic parameters between the two groups. The accumulation factor following multiple dosing was similar in both groups. Results suggest that nisoldipine dose should be optimized by monitoring of a pharmacodynamic end point, such as effect on blood pressure. It is likely that dose requirements for patients with liver disease will be lower. 相似文献
74.
Effect of age and disease duration on parkinsonian motor scores under levodopa therapy 总被引:1,自引:0,他引:1
G. Ransmayr G. Künig M. Neubauer M. Wagner M. Falk 《Journal of neural transmission (Vienna, Austria : 1996)》1995,9(2-3):177-188
Summary One hundred and fifty patients suffering from Parkinson's disease were analysed for the expression of the motor symptoms during optimum response to levodopa therapy (subscale III of the Unified Parkinson's Disease Rating Scale). Patients were grouped according to age (64, 65–74, 75 years). Disease duration and daily levodopa dosage were similar in the three groups. Pooled residual scores for posture and gait impairment (PGI), tremor (T), rigidity (R) and distal motor impairment (DMI; hand and foot movements) increased with age (Kruskal-Wallis ANOVA). The parkinsonian scores were significantly higher than the scores of 150 age-matched normal controls (Mann-Whitney U test). The differences between the patients' scores and the scores of the age-matched controls increased with age. In spite of a significant increase in the daily levodopa dosage with disease duration (linear regression), PGI aggravated age-dependently, and DMI age-independently with symptom duration (Spearman rank correlation). In contrast, T and R did not increase with disease duration. 相似文献
75.
Walther T Falk V Schneider J Walther C Mohr FW 《The Annals of thoracic surgery》1999,68(5):1858-9; discussion 1860
Stentless tricuspid valve replacement was performed in a 21-year-old patient with severe destructive tricuspid valve endocarditis resistant to medical therapy. Postoperative recovery was uneventful. Stentless atrioventricular valves are considered an additional treatment option besides stented valves or homograft implantations for severe right-sided endocarditis. Transvalvular hemodynamics are excellent, and right ventricular function can be preserved by suspending the valve at the papillary muscles. 相似文献
76.
Two groups of rats given daily, 3-h, intermittent food-pellet sessions, which induced polydipsia, drank either cocaine (COC) or lidocaine (LIDO) solutions. Then water was made available concurrently, but neither group preferred drug solution. When drug was presented in a glucose-saccharin vehicle, which was subsequently faded out, both the COC and LIDO groups acquired a strong preference for drug solution rather than water. Half of each group was continued, and half was directly faded to a preference for the other drug solution rather than water. Then COC and LIDO solutions were available concurrently and animals overwhelmingly preferred the drug solution that historically had been associated with the glucose-saccharin vehicle. Finally, the COC-preferring and LIDO-preferring groups had the concentrations of their preferred drug increased step-wise several times and preferences were maintained. Thus, acquired drug preferences remained stable as preferred drug concentration was increased, making it more bitter than the nonpreferred drug. The abuse potential of COC affords it little advantage over LIDO in the institution and maintenance of oral drug preference, suggesting that the post-ingestive pharmacological action of a drug is less important for acquiring drug-taking than is a history of associating the drug with another reinforcing event. 相似文献
77.
Herzig KA Falk MC Jonsson JR Axelsen RA Griffin AD Hawley CM Rigby RJ Cobcroft R Nicol DL Powell EE Johnson DW 《Transplantation》2000,70(1):149-152
BACKGROUND: In this report we describe a malignant lymphoma of donor origin inadvertently transplanted into two renal allograft recipients, despite standard comprehensive donor screening. The successful clearance of the tumor from both patients and a novel method of surveillance are detailed. METHODS: Initial management consisted of withdrawal of immunosuppression to promote rejection of the allograft and the transplanted tumor in both patients, followed by graft removal. Peripheral blood microchimerism was assessed in both recipients using nested polymerase chain reaction to detect the DYZ3 gene on the Y chromosome (donor male, recipients female). RESULTS: Although microchimerism was detected on day 6 after transplantation and day 1 after explantation, repeat peripheral blood examination at 1, 3, and 6 months after explantation demonstrated no microchimerism. Both patients remain well at 12 months and have been relisted for transplantation. CONCLUSION: Despite inadvertent transplantation of a previously undiagnosed malignancy of donor origin, the recipients' immune response was able to eliminate donor tumor cells after the withdrawal of immunosuppression. Repeated surveillance of peripheral blood from both recipients, using a novel application of the technique of nested polymerase chain reaction to amplify donor DNA, demonstrated no persistence of donor cells, supporting effective eradication of the donor malignancy. 相似文献
78.
79.
A prospective study of methylenetetrahydrofolate reductase and methionine synthase gene polymorphisms, and risk of colorectal adenoma 总被引:8,自引:2,他引:8
Chen J; Giovannucci E; Hankinson SE; Ma J; Willett WC; Spiegelman D; Kelsey KT; Hunter DJ 《Carcinogenesis》1998,19(12):2129-2132
We examined the relationship between a functional polymorphism (667C--
>T, ala-->val) of the methylenetetrahydrofolate reductase gene
(MTHFR) and the risk of colorectal adenomas in the prospective Nurses'
Health Study. Among 257 incident polyp cases and 713 controls, the MTHFR
val/val polymorphism [relative risk (RR) = 1.35, 95% confidence interval
(CI) 0.84-2.17] was not significantly associated with risk of adenomas.
This lack of association was observed for both small (RR = 1.36, 95% CI
0.76-2.45) and large (RR = 1.32, 95% CI 0.66-2.66) adenomas. Furthermore,
there was no significant interaction between this polymorphism and
consumption of either folate, methionine or alcohol. We also examined the
relationship of a newly identified polymorphism (asp919gly) of the
methionine synthase gene (MS) with the risk of colorectal adenomas in the
same population. The MS gly/gly polymorphism was also not significantly
associated with risk of colorectal adenomas (RR = 0.66, 95% CI 0.26-1.70).
These results, which need to be confirmed in other studies, suggest that
the MTHFR val/val polymorphism, which has been previously inversely
associated with risk of colorectal cancer, plays a role only in a late
stage (adenoma-- >carcinoma) of colorectal tumorigenesis, and/or may
protect against malignant transformation in the subset of benign adenomas,
which may progress to malignancy.
相似文献
80.