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31.
Uterine leiomyomas in the infertile patient: preoperative localization with MR imaging versus US and hysterosalpingography 总被引:2,自引:0,他引:2
Eleven women with a history of infertility and uterine leiomyomas underwent magnetic resonance (MR) imaging of the pelvis prior to myomectomy. Nine also underwent preoperative pelvic ultrasonography (US), and ten underwent hysterosalpingography. All studies were interpreted prospectively by independent observers. With each imaging modality, the location (one of 11 anatomic segments), size, and appearance of detected uterine leiomyomas were determined and compared with surgical and histologic findings. Among the nine patients who underwent both MR and US, the sensitivity (85%) and accuracy (94%) of MR imaging for abnormal segments was significantly better than that of US (sensitivity = 69%, P = .015; accuracy = 87%, P = .043). For the ten patients who underwent both MR and hysterosalpingography, the sensitivity (91%) and accuracy (96%) of MR imaging was better than that of hysterosalpingography (sensitivity = 18%, P = .0005; accuracy = 72%, P = .0005). The specificities of the three modalities did not significantly differ (100%, 97%, and 98% for MR, US, and hysterosalpingography, respectively). These data suggest that MR imaging is superior to US or hysterosalpingography for preoperatively locating uterine leiomyomas. 相似文献
32.
33.
Concepts necessary to an understanding of the basics of quality assurance audits are presented. Included are specific examples that bridged theory and practice by applying the protocol to a real-life diagnostic imaging situation. This method meets the present requirements of the Joint Commission of the Accrediation of Hospitals. 相似文献
34.
Patient dosage in computed tomography 总被引:1,自引:0,他引:1
35.
Background
The purpose of this study was to determine the test-retest reliability of temporal and spatial gait measurements over a one-week period as measured using an instrumented walkway system (GAITRite®).Methods
Subjects were tested on two occasions one week apart. Measurements were made at preferred and fast walking speeds using the GAITRite® system. Measurements tested included walking speed, step length, stride length, base of support, step time, stride time, swing time, stance time, single and double support times, and toe in-toe out angle.Results
Twenty-one healthy subjects participated in this study. The group consisted of 12 men and 9 women, with an average age of 34 years (range: 19 – 59 years). At preferred walking speed, all gait measurements had ICC's of 0.92 and higher, except base of support which had an ICC of 0.80. At fast walking speed all gait measurements had ICC's above 0.89 except base of support (ICC = 0.79),Conclusions
Spatial-temporal gait measurements demonstrate good to excellent test-retest reliability over a one-week time span.36.
Vingerhoets G Deblaere K Backes WH Achten E Boon P Boon PJ Hofman P Vermeulen J Vonck K Wilmink J Aldenkamp AP 《Epilepsy & behavior : E&B》2004,5(Z1):S81-S89
This contribution aims to review the major findings of pre- and postsurgical functional magnetic resonance imaging (fMRI) in patients with refractory epilepsy from a neuropsychological perspective. We compared the contribution of fMRI with the intracarotid amytal procedure (IAP) with respect to functional mapping of language and memory in patients with therapy-resistant epilepsy. We conclude that using comprehensive language paradigms, fMRI has been able (1) to provide estimates of the degree of language lateralization including the degree of involvement of the nondominant hemisphere, (2) to provide information on the location of its activated network during expressive and receptive language, and (3) to help delineate eloquent language regions in the vicinity of the surgical target, thus preventing postoperative complications. The contribution of the frequently observed nondominant hemisphere activation to language should be explored and its clinical relevance determined. Evidence from fMRI studies is accumulating that reorganization of cognitive and motor function favors the activation of contralateral homotopic areas, although this process is far from understood. The exact functional contribution of atypical areas of activation should be investigated critically. In the presurgical evaluation process, detailed and reliable localization of language and memory functions of the individual patient is mandatory and should be the ultimate goal in the development of comprehensive clinical fMRI protocols. 相似文献
37.
Neural signals from proprioceptors in muscles provide length and force-related linkages among muscles of the limbs. The functions of this network of heterogenic reflexes remain unclear. New data are reported here on the distribution and magnitudes of neural feedback among quadriceps and triceps surae muscles in the decerebrate cat. The purpose of this paper was to distinguish whether inhibitory-force feedback is directed against muscles by virtue of the motor-unit composition or articulation of the muscle. These studies were carried out using controlled stretches and measurements of the resulting force responses of individual quadriceps and triceps surae muscles. Responses were evoked over a wide range of background force levels. In agreement with earlier electrophysiological studies, excitatory length feedback strongly linked the vastus muscles, but excitatory reflexes between each vastus and rectus femoris muscles were weak. We also observed a substantial excitatory linkage from the vastus muscles to the soleus muscle. In contrast, force-related inhibition was absent in the heterogenic reflexes among the vastus muscles but strong and bidirectional between each vastus muscle and the rectus femoris muscle and between triceps surae and quadriceps muscles. We conclude that short-latency feedback in the hindlimb is organized according to muscle articulation. Length feedback within muscle groups regulates joint stiffness while interjoint length feedback may compensate for the effects of nonuniform inertial properties of the limb. Force feedback is organized to regulate coupling between joints and, along with length feedback, determine the mechanical properties of the endpoint. 相似文献
38.
OBJECTIVES:
To determine patterns of follow-up and prenatal education by family physicians and to assess whether practice patterns comply with the 1996 Canadian Paediatric Society/Society of Obstetricians and Gynecologists of Canada (CPS/SOGC) guidelines for early neonatal discharge.DESIGN:
Mail survey.SETTING:
A community of 300,000 people who were served exclusively for obstetrical care by a tertiary care hospital that performs 5000 deliveries per year and provides an early discharge program (EDP).PARTICIPANTS:
Family physicians who provide prenatal and/or newborn care.MAIN OUTCOME MEASURES:
The timing of neonatal follow-up and parental teaching by family physicians.RESULTS:
Thirty-two per cent of the respondents scheduled their first postnatal visits two or more weeks after early discharge. There was no significant difference (P=0.7) in scheduling of follow-up for babies who were part of an EDP compared with those who were not. Fewer than 20% of physician respondents provided antenatal education in preparation for early discharge.CONCLUSIONS:
The 1996 CPS/SOGC guidelines for physician follow-up after early neonatal discharge and for anticipatory parental education are not being followed consistently; however, these guidelines were disseminated without reinforcement. Until further study supports a change in practice guidelines, appropriate implementation strategies must be employed to ensure compliance. 相似文献39.
Tredwell SJ Wilson D Wilmink MA;Canadian Early Mid-Trimester Amniocentesis Trial Group 《Journal of pediatric orthopedics》2001,21(5):636-641
A recent publication by the Canadian Early and Mid-Trimester Amniocentesis Trial Group reported an increase in orthopaedic foot deformities in infants whose mothers underwent an amniocentesis from 11 to 12 + 6 gestational weeks versus a group sampled between 15 to 16 + 6 gestational weeks. Because the sampling of the former group was at the time of maximum foot growth and maximum acquisition of amniotic fluid, the authors hypothesize that the foot deformities are secondary to decreased fetal movement during a key phase in foot and ankle development. 相似文献
40.
Three sibs all presented in the early neonatal period with a salt-losing syndrome. The salt-losing form of congenital adrenal hyperplasia was diagnosed and appropriate treatment with glucocorticosteroids, mineralocorticosteroids, and additional dietary salt started. Although early life was maintained with difficulty, with age all 3 children required decreasing amounts of replacement steroids to maintain normal plasma electrolyte balance. They were reinvestigated at the ages of 15 years and 8 years (twins), when cortisol synthesis and metabolism proved normal, but aldosterone synthesis was blocked by deficiency of 18-dehydrogenase. Rational treatment of these cases of a salt-losing syndrome in which aldosterone synthesis alone is blocked due to lack of the enzyme 18-dehydrogenase requires the administration of a mineralocorticosteroid drug only. Since deoxycorticosterone (acetate or pivalate) requires intramuscular administration, as life-long therapy oral fludrocortisone is preferable. Although fludrocortisone has glucocorticoid activity, the "hydrocortisone equivalent" effect of the small dosage used was unlikely to inhibit either pituitary corticotrophin or growth hormone production. 相似文献