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1.
Zia Hossein Ma Joseph K. H. O'Donnell John P. Luzzi Louis A. 《Pharmaceutical research》1991,8(4):502-504
Dimethyl isosorbide (DMI), which is currently under investigation for its potential use as a pharmaceutical vehicle and drug permeation enhancer, is a water-miscible liquid with relatively low viscosity. The solubilization behavior of DMI as a cosolvent for nonpolar drugs was characterized via dielectric constant measurements of binary solvent systems containing DMI and either water, propylene glycol (PG), or polyethylene glycol (PEG). Evidence from the dielectric constant profiles and NMR studies suggest that DMI undergoes complexation with water and PG, but not with PEG, through hydrogen bonding interactions. The solvent complexation exhibited a major effect on the solubilities of prednisone, dexamethasone, and prednisolone in the mixed solvent systems. Maximum solubility of each drug was found to occur near a DMI/water or DMI/PG concentration ratio of 1:2. In the DMI–PEG mixed system, while there is no apparent interaction between DMI and PEG molecules, the solubility of prednisone was found to increase with decreasing dielectric constant. 相似文献
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The use of 3D surface fitting for robust polyp detection and classification in CT colonography 总被引:3,自引:0,他引:3
In this paper we describe the development of a computationally efficient computer-aided detection (CAD) algorithm based on the evaluation of the surface morphology that is employed for the detection of colonic polyps in computed tomography (CT) colonography. Initial polyp candidate voxels were detected using the surface normal intersection values. These candidate voxels were clustered using the normal direction, convexity test, region growing and Gaussian distribution. The local colonic surface was classified as polyp or fold using a feature normalized nearest neighborhood classifier. The main merit of this paper is the methodology applied to select the robust features derived from the colon surface that have a high discriminative power for polyp/fold classification. The devised polyp detection scheme entails a low computational overhead (typically takes 2.20 min per dataset) and shows 100% sensitivity for phantom polyps greater than 5 mm. It also shows 100% sensitivity for real polyps larger than 10 mm and 91.67% sensitivity for polyps between 5 to 10 mm with an average of 4.5 false positives per dataset. The experimental data indicates that the proposed CAD polyp detection scheme outperforms other techniques that identify the polyps using features that sample the colon surface curvature especially when applied to low-dose datasets. 相似文献
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Prof. Dr. F. A. Spengel G. Küffer H. Stiegler 《Journal of molecular medicine (Berlin, Germany)》1993,71(4):323-326
Summary The efficacy and safety of recombinant tissue-type plasminogen activator (rt-PA) was evaluated in 46 patients with thrombembolic arterial occlusions in leg arteries. rt-PA was given over 1–4 h with a maximum dose of 18 mg. The effect of rt-PA treatment was determined as patency of the occluded arteries in 44 different patients 14 days after treatment. In 41 patients at least one artery was recanalized (93%) by rt-PA, and in almost half of these patients (48%) no residual stenosis were detected after the lytic treatment. A slight residual stenosis was detected in 29% of the patients and a severe residual stenosis in 21%. An additional treatment with percutaneous transluminal angioplasty was performed in 23 of the 44 patients and successful in 21 (91%). In 8 patients an addition catheter-embolectomy was performed. No difference in patency rate was detected between patients with thrombotic and those with embolic occlusions. The age of the occlusion influenced the patency rate; occlusions under the age of 5 weeks showed a patency rate of 96% compared to 82% in older occlusions. The length of the occlusion did not have any influence on the outcome of the rt-PA treatment. From the results of this open study we conclude that a dose of up to 18 mg of rt-PA is both safe and effective in the treatment of thromboembolic occlusions in leg arteries.Abbreviations rt-PA
recombinant tissue-type plasminogen activator
- GGT
gamma-glutamyltransferase
- SGOT
aspartate aminotransferase
- SGPT
alanine aminotransferase
- LDH
lactate dehydrogenase
- PTA
percutaneous transluminal angioplasty
Dedicated to Prof. Dr. N. Zöllner on the occasion of his 70th birthday 相似文献
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Ubaldi F Rienzi L Ferrero S Anniballo R Iacobelli M Cobellis L Greco E 《Human reproduction (Oxford, England)》2002,17(6):1544-1547
BACKGROUND: Glucocorticoids have been used in conjunction with zona dissection to improve pregnancy and implantation rates in IVF patients. The aim of this prospective randomized study was to evaluate the effect of low-dose prednisolone in addition to the standard protocol, on pregnancy and implantation rates in routine ICSI patients before and after embryo replacement. METHODS: A total of 313 patients in 360 consecutive cycles (patients <39 years old and with three or less than three ICSI attempts) performed at our centre were randomly assigned by computer-generated list to receive either prednisolone (10 mg/day in two divided doses), starting on the first day of ovarian stimulation and continuing for 4 weeks (group A), or no treatment (group B). RESULTS: The mean age, number of previously failed IVF attempts, basal FSH levels and the mean rank of trials were comparable between groups A and B. The mean (+/- SD) number of metaphase II oocytes retrieved (11.9 +/- 5.5 versus 12.0 +/- 5.1), 2-pronuclei fertilization rate (67.2 versus 65.8%), the pregnancy and the implantation rates were not different between the study and control groups (49.0 and 23.6% versus 50.0 and 23.3% respectively). CONCLUSION: Low-dose prednisolone treatment in addition to the standard protocol before and after embryo replacement does not appear to have a significant effect on pregnancy or implantation rates. 相似文献
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Intra-uterine insemination versus cyclic, low-dose prednisolone in couples with male antisperm antibodies 总被引:1,自引:1,他引:1
A total of 46 couples with male immunological infertility enteredthe trial at the infertility clinic of the Family Federationof Finland. The men all showed a positive mixed antiglobulinreaction to immunoglobulin G in their semen; 31 men were alsotested for sperm-bound IgA immunoglobulins by flow cytometry.Serum antisperm antibodies were checked in a tray agglutinationtest. The women showed normal reproductive endocrinology andat least one patent Fallopian tube. The couples were randomizedto undergo either up to three intra-uterine inseminations (IUI),or timed intercourse with cyclic, low-dose (20 mg) prednisolonetherapy of the men. Cross-over was carried out if no pregnancyoccurred in the first stage. Timing of ovulation was based onurinary luteinizing hormone assay and transvaginal ultrasonographicmeasurements. In all, 40 couples either completed the studyor the female partner conceived. IUI was significantly better(P = 0.04) with nine pregnancies than timed intercourse withprednisolone (one pregnancy). There were no significant associationsbetween antibody levels, sperm count or motility versus theincidence of pregnancy. In male immunological infertility, well-timedIUI is an effective treatment method: results are obtained rapidlyand steroidal side-effects can be avoided. 相似文献
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John A. Wolfe Bruce E. Stuck Steven T. Schuschereba Leslie P. Fox 《Documenta ophthalmologica. Advances in ophthalmology》1985,59(3):277-299
A moderately severe thermal injury of the central cornea of 48 Dutch-belted rabbit eyes was produced with a carbon (CO2) laser. The lesions were photographed with a slit lamp (SL) camera immediately following the injury and at 1, 2, 4, 7, 14, 21, 30 and 60 days after the exposure. Lesion size, opaqueness, and depth were graded clinically by SL biomicroscopy at the same intervals. No significant differences were found (p 0.05) between groups of eyes treated with flurbiprofen (0.03%), prednisolone acetate (1%), and vehicle control four-times-a-day for three weeks following injury. Additionally, eyes were studied histopathologically at 3 and 60 days following injury by light and transmission electron microscopy, and clinically at 30 and 60 days by endothelial specular microscopy. Important clinical and histopathological findings included coagulative necrosis of the corneal epithelium, epithelial sloughing, fusion of stromal collagen, stromal edema and inflammatory cell infiltration, stromal scar formation, corneal thinning, endothelial hyperplasia and metaplasia, fibrinous anterior chamber reaction with hypopyon, and retrocorneal fibrous membrane formation. 相似文献