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81.
82.
The right mid-lung window 总被引:1,自引:0,他引:1
Goodman LR; Golkow RS; Steiner RM; Teplick SK; Haskin ME; Himmelstein E; Teplick JG 《Radiology》1982,143(1):135
83.
Occult malignant breast lesions in 114 patients: relationship to age and the presence of microcalcifications 总被引:2,自引:0,他引:2
Hermann G; Janus C; Schwartz IS; Papatestas A; Hermann DG; Rabinowitz JG 《Radiology》1988,169(2):321-324
This study evaluates the mammographic findings in 352 patients, aged 30-85 years, who underwent spot localization and biopsy for evaluation of nonpalpable breast abnormalities. Malignancy was found at biopsy in 114 cases. The mammographic appearance (specifically, whether grouped microcalcifications, mass, or both were present) was correlated with patient age and histologic findings (specifically, whether the pathologic changes were infiltrating or noninfiltrating in nature). The prevalence of malignant conditions increased directly with age. The presence of grouped microcalcifications as the sole indicator of malignancy was seen in 100% (seven of seven) of the patients in the 30-39-year age group, 64% (18 of 28) in the 40-49-year age group, 37% (11 of 30) in the 50-59-year age group, 30% (seven of 23) in the 60-69-year age group, and 23% (six of 26) in the 70-85-year age group. Of the 49 tumors that were manifested solely as microcalcifications, 34 (69%) were noninfiltrating. The finding of grouped microcalcifications should be aggressively investigated, since it may indicate noninfiltrating carcinoma in an early stage, when the potential for cure is greatest. 相似文献
84.
R Emshoff A Rudisch K Innerhofer R B?sch S Bertram 《International journal of oral and maxillofacial surgery》2001,30(5):390-396
The purpose of this study was to investigate whether in patients with a clinical unilateral temporomandibular joint (TMJ)-related finding of internal derangement type (ID)-III (disk displacement without reduction) in combination with TMJ-related pain, the intraindividual variable of 'unilateral TMJ ID-III pain' may be linked to subject-related magnetic resonance (MR) imaging findings of TMJ ID, and TMJ osteoarthrosis (OA). The study comprised 48 consecutive TMJ pain patients, who were assigned a clinical unilateral TMJ pain side-related diagnosis of ID-III. Bilateral sagittal and coronal MR images were obtained to establish the presence or absence of TMJ ID and/or OA. Comparison of the TMJ side-related data showed a significant relationship between the clinical finding of TMJ ID-III pain and the MR imaging diagnoses of TMJ ID (P=0.000) and TMJ ID type (P=0.000). There was no correlation between the clinical finding of TMJ ID-III pain and the MR imaging diagnosis of TMJ OA (P=0.217), nor between the MR imaging diagnosis of TMJ OA and that of TMJ ID (P=0.350). Regarding the diagnostic subgroups of TMJ ID, a significant relationship was found between the presence of TMJ OA and the MR imaging diagnoses of TMJ ID type(P=0.002). Use of the Kappa statistical test indicated a fair diagnostic agreement between the presence of TMJ ID-III pain and the MR imaging diagnosis of disk displacement without reduction (DDNR) (K=0.42). The results suggest that TMJ ID-III pain is related to TMJ-related MR imaging diagnoses of ID. Further, the data confirm the biological concept of 'DDNR and OA' as an underlying mechanism in the etiology of TMJ-related pain and dysfunction. 相似文献
85.
PURPOSE: This study emphasizes the significance of maxillofacial injuries in skiing accidents, correlating injury mechanisms and patterns, by evaluating a large population of maxillofacial injuries over a 6-year period. PATIENTS AND METHODS: Between 1991 and 1996, of 5,623 patients showing oral and maxillofacial injuries, 1,859 were sports-related. Records of 579 patients with 882 incidents of oral and maxillofacial injury due to skiing were reviewed and analyzed according to age, sex, type of injury, cause of accident, location, and frequency of fractures. Additionally, the five main injury mechanisms were analyzed. RESULTS: The oral and maxillofacial injuries in 10.3% of all trauma patients, or 33% of all sports-related trauma patients, were due to skiing. A total of 310 patients (53.5%) had facial bone fractures, 236 patients (40.8%) suffered from dentoalveolar trauma, and 336 patients (58%) showed soft tissue injuries. Five major causes and mechanisms of injury existed, namely, 263 falls (45%); 135 collisions with other skiers (23%); 70 individuals struck by their own ski equipment (12%); 46 collisions against stationary objects (8%); and 34 lift-track accidents (6%). Sex distribution showed an overall male-to-female ratio of 1.9:1.0, but varied depending on the injury mechanism. The age distribution ranged from 2 to 81 years. CONCLUSION: The results of this study show the high incidence of oral and maxillofacial injuries due to skiing accidents. Depending on the mechanism of injury, different patterns occur. Facial bone fractures are more likely in collisions with other persons, falls, and collisions with stationary objects, whereas dentoalveolar trauma is more common when persons are struck by their own ski equipment, or when accidents on lift-tracks occur. 相似文献
86.
Diagnosing TMJ internal derangement and osteoarthritis with magnetic resonance imaging. 总被引:3,自引:0,他引:3
S Bertram A Rudisch K Innerhofer E Pümpel G Grubwieser R Emshoff 《Journal of the American Dental Association (1939)》2001,132(6):753-761
BACKGROUND: The authors conducted a study to investigate the relationship between the presence of temporomandibular joint, or TMJ, pain and magnetic resonance imaging, or MRI, findings of internal derangement, or ID, and arthritis, or OA. METHODS: The authors studied 131 consecutively seen TMJ pain patients. Their criteria for including a patient in the study were report of unilateral orofacial pain referred to TMJ and the presence of unilateral TMJ pain during palpation, function, and unassisted or assisted mandibular opening. The authors took bilateral sagittal and coronal MRIs to establish the presence or absence of TMJ ID, OA or both. RESULTS: When the authors compared TMJ side-related data from all subjects, they found a significant relationship between the clinical findings of TMJ pain and the MRI diagnoses of TMJ ID (P = .000) and TMJ OA (P = .013). They also found a significant relationship between the MRI diagnosis of TMJ ID type and that of TMJ OA (P = .000). The authors used the kappa statistical test and found poor diagnostic agreement between the presence of TMJ pain and the MRI diagnosis of TMJ ID (kappa = 0.21), TMJ OA (kappa = 0.15), and TMJ ID and OA combined (kappa = 0.18). CONCLUSIONS: The study's findings suggest that while clinical pain is related to TMJ-related MRI findings, the presence of clinical pain is not a reliable predictor of TMJ ID, OA or both. CLINICAL IMPLICATIONS: Using MRI to supplement clinical findings of TMJ pain appears warranted and necessary to establish the presence or absence of TMJ ID. 相似文献
87.
88.
S. Jank B. Norer S. Maurer-Stockinger R. Emshoff G. R?thler H. Strobl und E. Waldhart 《Mund-, Kiefer- und Gesichtschirurgie》2001,5(6):348-352
Zusammenfassung
Fragestellung. Ziel der vorliegenden Arbeit war es, Langzeitergebnisse erst- und zweitgradig luxierter Z?hne zu erhalten. Es sollten die
Sensibilit?t auf CO2-Schnee und Pulpenver?nderungen in Abh?ngigkeit von der Schienungsdauer untersucht werden.
Material und Methode. Insgesamt wurden die Daten von 725 Patienten über einen Zeitraum von 14 Jahren ausgewertet, wovon 108 Patienten nachuntersucht
werden konnten.
Ergebnisse. Bis 14 Monate nach dem Unfallzeitpunkt besteht ein signifikanter Zusammenhang zwischen Luxationsgrad und Sensibilit?t, welcher
auch in der Langzeitbeobachtung ab 36 Monaten wieder best?tigt werden konnte. Es wurde kein signifikanter Zusammenhang zwischen
einem erst- oder zweitgradigen Luxationstrauma und dem Auftreten apikaler Aufhellungen , dem Auftreten von Wurzelresorptionserscheinungen
oder Pulpenkavumsklerosen und Obliterationen gefunden. Die Schienungsdauer hatte keinen signifikanten Einfluss auf pathologische
Erscheinungen auf der Wurzeloberfl?che.
Schlussfolgerung. Die posttraumatische Sensibilit?t auf CO2-Schnee h?ngt von der Schwere des Zahntraumas ab, was für die Inzidenz apikaler Aufhellungen sowie Pulpenkavumsklerosen und
Obliterationen nicht zutrifft. Die Schienungsdauer hat keinen Einfluss auf die Prognose erst- und zweitgradig luxierter Z?hne.
相似文献
89.
M. Arborati D. Benchorba I. Lesieur JG Bizot-Espiard B. Guardiola-Lemaitre MJ Chapman and E. Ninio 《Fundamental & clinical pharmacology》1997,11(1):68-77
Summary— Cholesteryl esters in the hydrophobic core of low-density lipoprotein (LDL) particles constitute a major molecular target during copper-mediated oxidation. To facilitate the rapid analysis and quantitation of the oxidative degradation of LDL cholesteryl esters, we describe a new approach based on light scattering detection following separation by HPLC. We have applied this approach to the evaluation of the protective capacity of a new synthetic antioxidant, S20478, during oxidation of LDL in the presence of copper ions. HPLC separation of cholesterol and the four major molecular species of cholesteryl esters (C16:0, C18:1, C18:2 and C20:4) of LDL was achieved in a single run of 20 min with high sensitivity (50 ng) and low background. Time course studies of the oxidative modification of LDL (ratio LDL protein: copper, 100 μg/mL: 1μM) revealed that the content of unsaturated cholesteryl esters (C20:4 and C18:2) decreased (–30% and –15%, respectively) within 90 min of copper-mediated oxidation, while only minor degradation (up to 15%) of monounsaturated (C18:1) and saturated (C16:0) esters occurred. At 24 hours of oxidation, only traces (< 5%) of the C20:4 and C18:2 esters were detectable; whereas 52% of the C18:1 ester remained (P < 0.01). Of the saturated esters, only minor proportions (35% or less) underwent oxidative modification. In addition, some 81% of free cholesterol was conserved as the native sterol. The synthetic antioxidant, S20478 (50 μM) was capable of inhibiting the initiation and the propagation of copper-mediated LDL oxidation as determined by the time- and dose-dependant inhibition of the formation of conjugated dienes and thiobarbituric acid-reactive substances, as well as the conservation of the net electrical charge of LDL; indeed S20478 conserved cholesteryl esters in their native form up to 24 hours. However, after prolonged exposure to copper ions (48 hours), only 47% of the unsaturated esters remained (C18:2, P < 0.05). Nonetheless, S20478 (10 μM) was more efficient in inhibiting copper-mediated LDL oxidation as compared to probucol at the same concentration. These findings suggest that S20478 may be of potential interest in a new antioxidant approach to therapeutic stabilisation and regression of atherosclerotic plaques. Moreover, this method should prove useful in the assessment of the integrity of native LDL, and provides a new chemical marker of the degree of LDL oxidation. 相似文献
90.
1. Ouabain is known to have natriuretic effects only at high doses, and therefore if endogenously produced ouabain has a role in the regulation of sodium excretion, the renal response to ouabain must be increased substantially in certain physiological situations. The aim of this study is to determine whether treatment with the mineralocorticoid, aldosterone, potentiates that natriuretic response to ouabain. 2. Six conscious sheep received renal arterial infusion of either vehicle or aldosterone (3 μg/h). Forty hours after commencement of infusion ouabain was infused into the renal artery at 400 μg/h for 60min. A second infusion of ouabain was administered on the 6th day of aldosterone treatment. 3. In the absence of aldosterone, the effects on sodium excretion produced by ouabain infusion at 400 μg/h into the renal artery were variable and not statistically significant. Ouabain infusion after 40 h of aldosterone treatment increased sodium excretion from 40 ± 14 to 676 ± 69 μmol/min in the second hour following cessation of ouabain infusion (P< 0.001). Ouabain infusion after 6 days of aldosterone treatment increased sodium excretion similarly. Ouabain-stimulated sodium excretion was significantly greater during aldosterone treatment compared to vehicle treatment (P<0.05). In contrast, no enhancement of effect was observed after acute treatment with aldosterone. 4. These results demonstrate potentiation of the natriuretic response to ouabain infusion by chronic mineralocorticoid treatment and suggest a potential role of endogenous digitalislike factor in the physiological control of sodium homeo stasisaldo sterone, endogenous digitalis-like factor, ouabain, sodium excretion. 相似文献