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Ivan Tkác Pierre-Gilles Henry Peter Andersen C Dirk Keene Walter C Low Rolf Gruetter 《Magnetic resonance in medicine》2004,52(3):478-484
An efficient shim system and an optimized localization sequence were used to measure in vivo 1H NMR spectra from cerebral cortex, hippocampus, striatum, and cerebellum of C57BL/6 mice at 9.4 T. The combination of automatic first- and second-order shimming (FASTMAP) with strong custom-designed second-order shim coils (shim strength up to 0.04 mT/cm2) was crucial to achieve high spectral resolution (water line width of 11-14 Hz). Requirements for second-order shim strengths to compensate field inhomogeneities in the mouse brain at 9.4 T were assessed. The achieved spectral quality (resolution, S/N, water suppression, localization performance) allowed reliable quantification of 16 brain metabolites (LCModel analysis) from 5-10-microL brain volumes. Significant regional differences (up to 2-fold, P < 0.05) were found for all quantified metabolites but Asp, Glc, and Gln. In contrast, 1H NMR spectra measured from the striatum of C57BL/6, CBA, and CBA/BL6 mice revealed only small (<13%, P < 0.05) interstrain differences in Gln, Glu, Ins, Lac, NAAG, and PE. It is concluded that 1H NMR spectroscopy at 9.4 T can provide precise biochemical information from distinct regions of the mouse brain noninvasively that can be used for monitoring of disease progression and treatment as well as phenotyping in transgenic mice models. 相似文献
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Kevin O'Brien Jean Wright Frances Conboy YeWeng Sanjie Nicky Mandall Stephen Chadwick Ivan Connolly Paul Cook David Birnie Mark Hammond Nigel Harradine David Lewis Cathy McDade Laura Mitchell Alison Murray Julian O'Neill Mike Read Stephen Robinson Dai Roberts-Harry Jonathan Sandler Ian Shaw 《American journal of orthodontics and dentofacial orthopedics》2003,124(3):234-43; quiz 339
This study evaluated the effectiveness of early orthodontic treatment with the Twin-block appliance for the developing Class II Division 1 malocclusion. This multicenter trial was carried out in the United Kingdom. A total of 174 children, aged 8 to 10 years old, with Class II Division 1 malocclusion were randomly allocated to receive treatment with a Twin-block appliance or to an untreated, control group. Data were collected at the start of the study and 15 months later. Results showed that early treatment with Twin-block appliances resulted in reduction of overjet, correction of molar relationships, and reduction in severity of malocclusion. Most of this correction was due to dentoalveolar change, but some was due to favorable skeletal change. Early treatment with the Twin-block appliance is effective in reducing overjet and severity of malocclusion. The small change in the skeletal relationship might not be considered clinically significant. 相似文献
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David G Witte Michael E Brune Sweta P Katwala Ivan Milicic Deanne Stolarik Yu-Hua Hui Kennan C Marsh James F Kerwin Michael D Meyer Arthur A Hancock 《The Journal of pharmacology and experimental therapeutics》2002,300(2):495-504
Fiduxosin is a new alpha(1)-adrenoceptor antagonist targeted for the treatment of symptomatic benign prostatic hyperplasia. The purpose of this study was to determine and compare the potencies of the alpha(1)-adrenoceptor antagonists terazosin, doxazosin, tamsulosin, and fiduxosin, based on relationships between plasma drug concentrations and blockade of phenylephrine (PE)-induced intraurethral (IUP) and mean arterial pressure (MAP) responses after single oral dosing in conscious male beagle dogs. Magnitude of blockade and plasma concentrations were evaluated at selected time points over 24 h. All drugs produced dose-dependent antagonism of PE-induced IUP and MAP responses. When IUP and MAP blockade effects were plotted against drug plasma concentrations, direct relationships were observed that were well described by the sigmoidal maximal effect model. IUP IC(50) values for terazosin, doxazosin, tamsulosin, and fiduxosin were 48.6, 48.7, 0.42, and 261 ng/ml, respectively. MAP IC(50) values were 12.2, 13.8, 1.07, and 1904 ng/ml, respectively. Uroselectivity index values, defined as MAP IC(50)/IUP IC(50), were 0.25, 0.28, 2.6, and 7.3, respectively. These results extend previous observations with terazosin in this model, showing that doxazosin exhibits a uroselectivity index comparable to terazosin, consistent with the lack of alpha(1)-adrenoceptor subtype selectivity or uroselectivity of these drugs. Tamsulosin, an alpha(1a)-/alpha(1d)-subtype selective agent, had an index value approximately 10-fold greater than the nonselective drugs. Based on its pharmacokinetic profile and a relative uroselectivity 29-fold greater than the nonselective drugs, fiduxosin is expected to exhibit greater selectivity for urethral compared with vascular alpha(1)-adrenoceptors in human and should be a novel, long-acting, uroselective alpha(1)-adrenoceptor antagonist. 相似文献
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Braunschweig Rainer Biesold Markus Beilicke Matthias Marintschev Ivan 《Trauma und Berufskrankheit》2002,4(1):S68-S73
Trauma und Berufskrankheit - Zusammenfassung Der Nachweis oder Ausschluss ossärer Verletzungen am Ellbogengelenk wird primär mit der Projektionsradiographie in 2 Ebenen geführt.... 相似文献
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Retroperitoneal leiomyosarcoma mimicking acute appendicitis: laparoscopic management. 总被引:2,自引:0,他引:2
Ferdinando Agresta Paolo De Simone Ivan Michelet Natalino Bedin 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2003,7(2):177-179
BACKGROUND: Retroperitoneal leiomyosarcomas (RLMS) are a challenging clinical entity. The vast majority of patients are operated on when tumors are advanced. We report herein a case of RLMS, mimicking acute appendiceal disease and treated successfully via laparoscopy. METHODS: A 37-year-old woman, para 1, was admitted to our department for right lower quadrant abdominal pain, fever, and leukocytosis. She had no changes in gastrointestinal and urologic function. A physical examination revealed the presence of abdominal guarding, rebound, and a tender mass in the right lower quadrant. The abdominal ultrasound showed an inhomogeneous ovoid mass (6 cm in diameter) located below the cecum, with no definite margins, and consistent with an appendiceal abscess. The patient was referred for laparoscopy. The procedure was performed with the aid of 3 ports: a 12-mm trocar in the umbilicus (open technique), a 10-mm trocar in the left iliac fossa, and a 5-mm one in the supra-pubic space. On inspection of the abdominal cavity, a retroperitoneal 6-cm mass was immediately found below the cecum and the appendix. Neither intraperitoneal seeding nor suspected lymph nodes were present. After dissection of the parietal peritoneum, the mass appeared to be encapsulated and well demarcated from all surrounding structures. It was eventually dissected and removed via a plastic bag. A standard appendectomy was also performed. The postoperative course was uneventful, and the patient was discharged on the 3rd day. The histology analysis of the resected specimen showed a totally excised G2 leiomyosarcoma. The appendix had no signs of inflammation. Postoperatively, the patient underwent a total-body CT-scan, which had no signs of residual or distant disease. No adjuvant therapy was necessary. At an 18-month follow-up, the patient was doing well and was disease free. CONCLUSION: Surgery represents the main therapeutic option for resectable RLMS. Laparoscopy is a useful diagnostic tool that allows safe resection of incidentally discovered, small and well encapsulated RLMS. 相似文献
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Peter Kokol Marjan Mernik Jernej Završnik Kurt Kancler Ivan Malčić 《Journal of medical systems》1994,18(4):201-206
Computerized information systems, especially decision support systems, have become an increasingly important role in medical applications, particularly in those where important decision must be made effectively and reliably. But the possibility of using computers in medical decision making is limited by many difficulties, including the complexity of conventional computer languages, methodologies and tools. Thus a conceptual simple decision making model with the possibility of automating learning should be used. In this paper we introduce a cardiological knowledge-based system based on the decision tree approach supporting the mitral valve prolapse determination. Prolapse is defined as the displacement of a bodily part from its normal position. The term mitral valve prolaps (PMV), therefore, implies that the mitral leaflets are displaced relative to some structure, generally taken to be the mitral annulus. The implications of the PMV are the following: disturbed normal laminar blood flow, turbulence of the blood flow, injury of the chordae tendinae, the possibility of thrombus's composition, bacterial endocarditis, and finally hemodynamic changes defined as mitral insufficiency and mitral regurgitation. Uncertainty persists about how it should be diagnosed and about its clinical importance. It is our deep belief that the echocardiography enables properly trained experts armed with proper criteria to evaluate PMV almost 100%. But unfortunately, there are some problems concerned with the use of echocardiography. In that manner we have decided to start a research project aimed at finding new criteria and enabling the general practitioner to evaluate PMV using conventional methods and to select potential patients from the general population. To empower one to perform needed activities we have developed a computer tool called ROSE (computeRised prOlaps Syndrom dEtermination) based on algorithms of automatic learning. This tool supports the definition of new criteria and the selection of potential PMV-patients. 相似文献
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