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111.
Areas of signal loss in brain overlying air-containing structures at the skull base are commonly observed on axial fast MR images. The nature of this effect, which can mimic the appearance of cerebral hemorrhage, is investigated in a phantom study and in a normal volunteer. The magnitude of the signal loss is found to be inversely related to the distance of the scanning plane from the air-containing structure and directly related to the echo time. 相似文献
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T Hoshino L A Rodriguez K G Cho K S Lee C B Wilson M S Edwards V A Levin R L Davis 《Journal of neurosurgery》1988,69(6):839-842
The proliferative potential of low-grade astrocytomas was estimated in 47 patients. Each patient received an intravenous infusion of bromodeoxyuridine (BUdR), 150 to 200 mg/sq m, at the time of craniotomy to label cells in deoxyribonucleic acid (DNA) synthesis; the percentage of S-phase cells, or BUdR labeling index (LI), of each tumor was determined immunohistochemically. In 29 patients (60%), the tumors had BUdR LI's of less than 1%, indicating a slow growth rate; only three (10%) of these patients died of recurrent tumor during a follow-up period of up to 3 1/2 years. In contrast, of the 18 patients (40%) whose tumors had BUdR LI's of 1% or more, 12 (67%) had a recurrence and nine died during the same follow-up period. These results show that the proliferative potential, as reflected by the BUdR LI, is an important prognostic factor that separates low-grade astrocytomas into two groups and provides a more scientific rationale for selecting treatment for individual patients. 相似文献
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115.
Cabergoline: an advance in dopaminergic therapy 总被引:2,自引:0,他引:2
116.
117.
D. Davis J. Ulatowski S. Eleff M. Izuta S. Mori D. Shungu P. C. M. van Zijl 《Magnetic resonance in medicine》1994,31(4):454-460
Changes in the diffusion constant of water during reversible brain ischemia and cardiac arrest were monitored with a 10-s time resolution. Results (five cats, three rats) indicate that these changes are reversible and that the bulk of the changes are not caused by temperature or motion related to brain pulsations and blood flow. The rapid time course of the changes corresponds to the known time course for changes in energy state, signal transduction, and ionic homeostasis. 相似文献
118.
Christine B Ambrosone Mary K Nesline Warren Davis 《Cancer epidemiology, biomarkers & prevention》2006,15(9):1575-1577
The establishment of a biorepository with linkage to clinical and epidemiologic data will provide an invaluable resource for cancer research, including studies of cancer etiology, progression, and prognosis, as well as development of biomarkers for early detection. Developing an infrastructure for a biorepository linked to clinical, pathologic, and epidemiologic data requires significant efforts in strategic planning for efficient means to ascertain, identify, and consent participants, as well as guidelines for blood collection, processing, and storage while maintaining participant privacy rights. In this report, we present an approach to developing a Data Bank and Biorepository at our own institution, with discussion of elements to be considered when establishing such a bank. 相似文献
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120.
Joe I-Chiang Chou Hwai-Jen Fong Shou-Hsin Kuang Lin-Yang Gi Fang-Yi Hwang Yu-Chieng Lai Richard Che-Shoa Chang Shou-Yen Kao 《Journal of oral and maxillofacial surgery》2005,63(3):355-361
PURPOSE: This study was an analysis of the soft and hard tissue changes of the facial profile after bilateral sagittal splitting osteotomy for mandibular setback of Taiwanese patients. PATIENTS AND METHODS: We collected pre- and postsurgical lateral cephalographs of 64 patients (28 males, 36 females) with skeletal Class III malocclusion who received combined orthodontic-surgical treatment with bilateral sagittal splitting osteotomy mandibular setback at Taipei Veterans General Hospital between 1994 and 2000. Nineteen cephalometric parameters of (14 linear, 4 angular, and the BS index) soft and hard tissues were measured at 1 week before treatment, and 2 months and 1 year after surgery, and analyzed by paired t test. RESULTS: Mean patient age was 20.0 +/- 1.6 years. The patients underwent an average of 7 mm mandibular setback at the osseous pogonion (Pog). Average setbacks at Pog and soft tissue pogonion (pog) were 5.54 mm and 4.85 mm, respectively, at 1 year after surgery. The setback ratio of Pog/pog was 1:0.88. The hard tissue relapse at Pog was 21% at 1 year after surgery. Improvement in prognathic profile was demonstrated by significant changes in the positions of Pog and pog, ANB angle, the distance from lower lip to esthetic line (E-L lip), and the BS index after surgery. However, compared with parameters obtained from a normal Taiwanese population, the cephalometric data of Pog, pog, and BS index still indicated mild prognathism. CONCLUSION: Although mandibular prognathism could be grossly improved by bilateral sagittal splitting osteotomy mandibular setback, a significant amount of relapse occurred within 1 year after surgery. The extent of the postoperatively preserved features showing mandibular prognathism should be a concern for both patients and physicians. 相似文献