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Abnormal magnetic-resonance scans of the lumbar spine in asymptomatic subjects. A prospective investigation 总被引:36,自引:0,他引:36
S D Boden D O Davis T S Dina N J Patronas S W Wiesel 《The Journal of bone and joint surgery. American volume》1990,72(3):403-408
We performed magnetic resonance imaging on sixty-seven individuals who had never had low-back pain, sciatica, or neurogenic claudication. The scans were interpreted independently by three neuro-radiologists who had no knowledge about the presence or absence of clinical symptoms in the subjects. About one-third of the subjects were found to have a substantial abnormality. Of those who were less than sixty years old, 20 per cent had a herniated nucleus pulposus and one had spinal stenosis. In the group that was sixty years old or older, the findings were abnormal on about 57 per cent of the scans: 36 per cent of the subjects had a herniated nucleus pulposus and 21 per cent had spinal stenosis. There was degeneration or bulging of a disc at at least one lumbar level in 35 per cent of the subjects between twenty and thirty-nine years old and in all but one of the sixty to eighty-year-old subjects. In view of these findings in asymptomatic subjects, we concluded that abnormalities on magnetic resonance images must be strictly correlated with age and any clinical signs and symptoms before operative treatment is contemplated. 相似文献
3.
Leslee J. Shaw Romalisa Miranda-Peats Piotr Slomka John Friedman Sean W. Hayes Daniel S. Berman Gary V. Heller Marcin Dada William E. Boden Paul Casperson Robert A. O’Rourke Ronald Schwartz William S. Weintraub David J. Maron Spencer King Koon Teo Pamela Hartigan 《Journal of nuclear cardiology》2006,13(5):685-698
Background Stress gated myocardial perfusion single photon emission computed tomography (gSPECT) is increasingly used before and after
intercurrent therapeutic intervention and is the basis for ongoing evaluation in the Department of Veterans Affairs clinical
outcomes utilizing revascularization and aggressive drug evaluation (COURAGE) trial.
Methods and Results The COURAGE trial is a North American multicenter randomized clinical trial that enrolled 2287 patients to aggressive medical
therapy vs percutaneous coronary intervention plus aggressive medical therapy. Three COURAGE nuclear substudies have been
designed. The goals of substudy 0 are to examine the diagnostic accuracy of the extent and severity of inducible ischemia
at baseline in COURAGE patients compared with patient symptoms and quantitative coronary angiography and to explore the relationship
between inducible ischemia and the benefit from revascularization when added to medical therapy. Substudy 1 will correlate
the extent and severity of provocative ischemia with the frequency, quality, and instability of recurrent symptoms in postcatheterization
patients. Substudy 2 (n _ 300) will examine the usefulness of sequential gSPECT monitoring 6 to 18 months after therapeutic
intervention. Together, these nuclear substudies will evaluate the role of gSPECT to determine the effectiveness of aggressive
risk-factor modifications, lifestyle interventions, and anti-ischemic medical therapies with or without revascularization
in reducing patients’ ischemic burdens.
Conclusions The unfolding of evidence on the application of gSPECT in trials such as COURAGE defines a new era for nuclear cardiology.
We hope the evidence that emerges from the COURAGE trial will further establish the role of nuclear imaging in the evidence-based
management of patients with stable coronary disease.
The COURAGE trial was supported by the Cooperative Studies Program of the Department of Veterans Affairs Office of Research
and Development in collaboration with the Canadian Institutes of Health Research. Unrestricted research grants were obtained
from Merck & Co; Pfizer Pharmaceuticals; Bristol-Myers Squibb Medical Imaging; Astellas Pharma; Kos Pharmaceuticals; Data
Scope; Astra Zeneca Pharmaceuticals; Astra-Zeneca-Canada; Schering-Plough Coorporation, Ltd; Sanofi-Aventis, Inc; First Horizon;
and GE Healthcare. All industrial funding for this trial was directed through the Department of Veterans Affairs. Additional
funding for this substudy was provided by grants to the Department of Veterans Affairs and Canadian Institutes of Health Research
from Astellas Pharma and Bristol-Myers-Squibb Medical Imaging. 相似文献
4.
Herlinde Dumez Gunther Guetens Gert De Boeck Martin S Highley Robert A A Maes Allan T van Oosterom Ernst A de Bruijn 《Clinical chemistry and laboratory medicine》2004,42(11):1219-1227
Therapeutic drug monitoring generally focuses on the plasma compartment only. Differentiation between the total plasma concentration and the free fraction (plasma water) has been described for a number of limited drugs. Besides the plasma compartment, blood has also a cellular fraction which has by far the largest theoretical surface and volume for drug transport. It is with anti-cancer drugs that major progress has been made in the study of partition between the largest cellular blood compartment, i.e., erythrocytes, and the plasma compartment. The aim of the present review is to detail the progress made in predicting what a drug does in the body, i.e., pharmacodynamics including toxicity and plasma and/or red blood cell concentration monitoring. Furthermore, techniques generally used in anti-cancer drug monitoring are highlighted. Data for complex Bayesian statistical approaches and population kinetics studies are beyond the scope of this review, since this is generally limited to the plasma compartment only. 相似文献
5.
Thilo Klindert Isabel Stroetmann Gunther Seitz Georg Hfner Klaus Th. Wanner Gerlinde Frenzen Brigitta Eckhoff 《Archiv der Pharmazie》1997,330(6):163-168
A number of novel pyridazinomorphinans have been synthesized by the inverse electron demand Diels-Alder reaction of various 3,6-disubstituted 1,2,4,5-tetrazines with enamines derived from dihydrocodeinone and with codeinone. Reduction of some of the pyridazinomorphinans did not furnish the expected pyrroloepoxymorphinans; in all cases investigated reductive cleavage of the epoxybridge was observed to yield dihydropyridazino- or pyrrolomorphinans. The structures of all new compounds were assigned by the spectral data, that of the cycloadduct of codeinone was additionally verified by X-ray crystallography. Compounds 5a, 8, 11a , and 16 have been evaluated for their affinity at μ and κ opioid receptors in radioligand binding assays. Their ability to inhibit [3H]DAMGO binding at μ and [3H]U 69.593 binding at κ receptors, respectively as compared to codeine has been found to be lower. 相似文献
6.
Jonathan S. Jahr Fedor Lurie Bernd Driessen Jessica A. Davis Robert Gosselin Robert A. Gunther 《Journal canadien d'anesthésie》2002,49(3):243-248
PURPOSE: Accuracy of measurement of low hemoglobin concentrations using the HemoCue, a B-hemoglobin photometer (HemoCue AB, Angelholm, Sweden) may exhibit significant variability. Infusion of hemoglobin-based oxygen carriers (HBOC) results in low concentrations of plasma hemoglobin. Our study assessed B-hemoglobin photometer measurement accuracy of three HBOC: (hemoglobin glutamer-200 (bovine; Oxyglobin, Biopure Corp., Cambridge, MA, USA); hemoglobin glutamer-250 (bovine; Hemopure, Biopure Corp, Cambridge, MA, USA), and hemoglobin-raffimer, (human; Hemolink, Hemosol, Inc., Toronto, Ontario, Canada). METHODS: In the laboratory, 45 split canine plasma samples were mixed with hemoglobin glutamer-200 (8.13, 16.25, 32.5 g x L(-1) concentrations), 45 samples were mixed with hemoglobin glutamer-250 (8.13, 16.25, 32.5 g x L(-1) concentrations), 45 with hemoglobin-raffimer (12.5, 25.0, 50.0 g x L(-1) concentrations), and measured. Plasma samples without HBOC served as control. Hemoglobin concentration was determined by a laboratory analyzer (Coulter Corporation, Hiafeah, FL, USA) and B-hemoglobin photometer (HemoCue, Angelholm, Sweden). Two independent technicians performed blinded sample measurements and randomly tested each sample five times. Results were analyzed according to Bland and Altman analysis. RESULTS: B-hemoglobin photometer demonstrated high repeatability for all three HBOCs. Repeatability coefficients were 0.37 g x L(-1) and 0.48 g x L(-1) for hemoglobin glutamer-200, 0.39 g x L(-1) and 0.4 g x L(-1) for hemoglobin glutamer-250 and 1.07 g x L(-1) and 0.85 g x L(-1) for hemoglobin-raffimer. An acceptable agreement was found between the B-hemoglobin photometer and the laboratory analyzer for all three HBOCs tested. CONCLUSION: The B-hemoglobin photometer accurately determined the concentration of three HBOC solutions dissolved in canine plasma. 相似文献
7.
The internal anatomy of the median nerve in the region of the elbow has been studied by microdissection in 20 cadavers. Gross branching patterns were studied in an additional 14 cadavers. There are four major branches or branch groups: I to pronator teres, II to flexor carpi radialis, flexor digitorum superficialis, and palmaris longus; III to the anterior interosseous nerve; and IV to flexor digitorum superficialis. Three of these could be traced proximally within the main trunk of the median nerve, the average being I-10 cm; III-7.5 cm; IV-2 cm. This information should have clinical applications in repair and grafting of the median nerve near the elbow and in understanding clinical nerve compression sydromes. 相似文献
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Azulenes as Dienophiles in the [4+2]-Cycloaddition with Inverse Electron Demand, a Supplement [4+2] Cycloadditions of azulene ( 2 ) und 1-Nitroazulene ( 14 ) with the extremely electron-deficient, s-cis-fixed diazadiene system of 3,6-bis(trifluoromethyl)-1,2,4,5-tetrazine ( 1 ) are described. In addition to earlier findings 1 reacts with 2 probably in a two step [4+2] cycloaddition via 8 and 10 to yield the benzo[f]phthalazine 5a , via 8 and 9 to furnish the azuleno[d]pyridazine 3 and the azine 4 . The reaction of 1 with 1-Nitroazulene ( 14 ) leads to the azuleno[d]pyridazines 3 and 19 in low yield. 相似文献