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91.
Christopher Rokes MD Leena M. Ketonen MD PhD Greg N. Fuller MD PhD Jeffrey Weinberg MD John M. Slopis MD Johannes E.A. Wolff MD 《Pediatric blood & cancer》2009,53(4):672-674
Meningioangiomatosis (MA) is an uncommon brain tumor. The role of imaging techniques is underscored in cases where the tumor location makes resection (or even biopsy) dangerous. We report the case of a child with an MA tumor located deep in the right sylvian fissure. A computed tomography (CT) scan showed calcifications in a highly vascular lesion with surrounding edema. Magnetic resonance spectroscopy (MRS) showed a distinct choline (Cho) peak, which usually suggests a proliferating tumor. Fluorodeoxyglucose positron emission tomography (FDG‐PET) showed the lesion lacked hypermetabolic features. These radiological features should put MA in the differential diagnosis. Pediatr Blood Cancer 2009;53:672–674. © 2009 Wiley‐Liss, Inc. 相似文献
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Leena Katariina Saastamoinen Hannes Enlund Timo Juhani Klaukka 《The International journal of pharmacy practice》2008,16(3):155-167
Objective To investigate the characteristics, local agreements and changes regarding repeat prescribing processes in primary health care in Finland. Setting Twenty‐eight municipal health centres nationwide. Method Twenty‐eight physicians and 28 medical receptionists were given semi‐structured telephone interviews about repeat prescribing practices. The repeat prescribing process of each health centre was displayed as a flow chart and the processes were classified according to the quality of the practical flow and the medication review. Key findings There are various ways of carrying out repeat prescribing in different health centres. In some centres, a review of the medications is recognised as part of the repeat prescribing process, but in others there is no systematic review of the patients' medication. Repeat prescribing is often performed in a busy atmosphere. Repeat prescribing systems have evolved over time without proper management, and few local guidelines exist. Conclusions There is a need to reorganise the repeat prescribing systems in primary health care. A regular review of long‐term medications, in particular, needs to become a part of the repeat prescribing process. There is a need for both local and national guidelines. 相似文献
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Yrj U. Collan Matti J. Eskelinen Stig A. Nordling Pertti Lipponen Erkki Pesonen Leena M. Kumpusalo Pfkka Pajarinen Kauko O. Kettunen 《Acta oncologica (Stockholm, Sweden)》1994,33(8):873-878
We studied histological samples and clinical data from 111 breast carcinoma patients originally treated in 1975-1977 who did not have distant metastases at the time of diagnosis. A multivariate survival analysis using the Cox model selected the studied variables in the following order according to their prognostic association (breast cancer deaths, or deaths from any cause): axillary lymph node status, tumor size, mitotic index, and DNA ploidy status. The association of the different variables to the prognosis in respect to breast cancer deaths was evaluated 1-10 years after treatment by stepwise logistic regression. Lymph node status, tumor size, mitotic index, and DNA ploidy all showed significant relation to the prognosis but this association varied considerably with time of observation. 相似文献
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OBJECTIVE: The aim of this study was to investigate the effect of hormone-replacement therapy (HRT) on the pharmacokinetics of the selective monoamine oxidase B inhibitor selegiline and its primary metabolites desmethylselegiline and l-metamphetamine. METHODS: In this randomised, double-blind, cross-over trial, 12 healthy female subjects received once daily for 10 days either HRT containing 2 mg estradiol valerate and 250 microg levonorgestrel or matched placebo. On day 10, they took a single 10-mg oral dose of selegiline. The serum concentrations of selegiline, desmethylselegiline and metamphetamine were measured for 32 h. RESULTS: There was a 59% difference ( P=0.14) in the area under the serum concentration-time curve (AUC) of selegiline during the HRT compared with the placebo phase, but only a little or no concomitant reduction in the AUC of desmethylselegiline (-7%, P=0.071) or metamphetamine (2%, P=0.614) was observed. Maximum plasma concentration (C(max)) of selegiline was not changed, but a small, statistically significant, reduction in the C(max) of desmethylselegiline (-17%, P=0.03) was seen during the HRT phase. The C(max) of methamphetamine was slightly but not significantly reduced (-5%, P=0.06). The unchanged AUC ratios of desmethylselegiline/selegiline and metamphetamine/selegiline indicate that the primary metabolism of selegiline was not affected by HRT. All study treatments were well tolerated. CONCLUSION: Unlike oral contraceptives, HRT is not likely to have clinically significant pharmacokinetic interaction with selegiline. 相似文献
98.
Rheological properties of three component creams containing sorbitan monoesters as surfactants 总被引:7,自引:0,他引:7
Korhonen M Lehtonen J Hellen L Hirvonen J Yliruusi J 《International journal of pharmaceutics》2002,240(1-2):103-114
The objectives of the present study were (1) to evaluate the effect of formulation ingredients on the release rate of Ubiquinone from its adsorbing solid compact; and (2) to prepare and evaluate an optimized self-nanoemulsified tablet formulation. A three factor, three-level Box–Behnken design was used for the optimization procedure, with the amounts of copolyvidone (X1), maltodextrin (X2) and microcrystalline cellulose (X3) as the independent variables. The response variable was cumulative percent of Ubiquinone emulsified in 45 min with constraints on weight, flowability index, tensile strength, friability and disintegration time of the dry powdered emulsion and the resultant compact. Based on the experimental design, different Ubiquinone release rates and profiles were obtained. Mathematical equations and response surface plots were used to relate the dependent and independent variables. The regression equation generated for the cumulative percent emulsified in 45 min was Y6=64.10−12.32X1−4.36X2−25.53X3+6.99X1X2+3.97X1X3+9.70X2X3−8.98X12−16.22X22+17.10X32. The optimization model predicted an 85.4% release with X1, X2 and X3 levels of 66.6, 560.1 and 100, respectively. A new formulation was prepared according to these levels. The observed responses were in close agreement with the predicted values of the optimized formulation. 相似文献
99.
Gyürösiová L Laitinen L Raiman J Cizmárik J Sedlárová E Hirvonen J 《Pharmaceutical research》2002,19(2):162-168
Purpose. The purpose of the present research was to study 10 m-alkoxysubstituted pyrrolidinoethylesters of phenylcarbamic acid—potential local anesthetics. The relationships between the structure of the molecule, its physicochemical parameters (log Doct, log k, RM, solubility) were correlated to the permeability data obtained from permeation experiments in Caco-2 monolayers and excised human skin in vitro.
Methods. The extent and mechanism(s) of permeability of the series were studied through a Caco-2 monolayer in the apical-to-basolateral (a-b) and basolateral-to-apical (b-a) directions. The MTT test was performed to determine cellular damage. In vitro transdermal permeability data were obtained from permeation experiments on excised human skin by using side-by-side chambers. Passive diffusion and iontophoretically enhanced permeability were measured.
Results. In Caco-2 monolayers, similar results in the shape of the permeability curves were obtained for the two directions. In the b-a direction, the values of Papp were 2-6 times greater than in the a-b direction. A plot of drug permeability vs. the number of carbons in the alkoxychain plateaued first, after which the permeability decreased by the increasing lipophilicity of the drug. If the log Doct of the ester was 3.4 and the MW > 385 Da, no measurable Caco-2 permeability was found. Cell damage was also higher by the more lipophilic compounds. In excised human skin, the relationship between the passive diffusion of the drugs and the number of carbons in the alkoxychain was parabolic (r
2 = 0.95). Introducing low-level electrical current (iontophoresis), transdermal permeability of the more hydrophilic phenylcarbamic acid esters increased clearly.
Conclusions. Lipophilicity and solubility of a compound have crucial roles in the permeation process. A very high lipophilicity has, however, a negative influence on the permeability, both intestinally and transdermally. Iontophoresis significantly increases the diffusion of small and less lipophilic compounds. 相似文献
100.