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111.
Drayer  BP; Rosenbaum  AE; Reigel  DB; Bank  WO; Deeb  ZL 《Radiology》1977,124(2):349-357
The methodology and clinical use of metrizamide (Amipaque) computed tomography (CT) cisternography are described as applied in the cases of 22 children with morphologic and physiologic abnormalities affecting the cranial portion portion of the central nervous system. In contrast to pneumoencephalography, CT cisternography affords equivalent or superior visualization of the basal cranal subarachnoid spaces with simpler technique and low morbidity. Intrathecal metrizamide enchancement in children causes a very low incidence of side effects.  相似文献   
112.
The authors have assessed the role of computerized three-dimensional (3-D) and traditional (TD) radiotherapy planning and inhomogeneity corrections in improving target volume coverage and normal tissue sparing in carcinoma of the tongue. Coverage of target volumes in 3-D versus TD plans revealed the following. Volume receiving 95% of dose, clinical target volume (CTV): 1-68% versus 0-24%; gross tumour volume-lymph nodes (GTV-I): 0-80% versus 0-20%; gross tumour volume-primary tumour (GTV-II): 0-65% versus 0-26%. Dose to 95% of target volume CTV 77-92% versus 76-87%; GTV-I: 81-90% versus 61-88%; GTV-II: 82-93% versus 68-87%. Minimum dose to 5% of target volume, CTV: 77-93% versus 74-81%; GTV-I: 81-90% versus 61-88%; GTV-II: 76-93% versus 68-87%. Minimum dose to a volume of no less than 5% of the target volume, CTV: 93-98% versus 88-96%; GTV-I: 87-100% versus 88-97%; GTV-II: 86-98% versus 88-96%. A new parameter (inhomogeneity difference) was devised to study target volume dose homogeneity and was found to be very useful. Dose to two-thirds of the parotid glands in 3-D versus TD plans showed a mean of 46 versus 65% for right parotid glands and 44 versus 56% for left parotid glands in all patients. Better tumour dose homogeneity, increased mean tumour dose, avoidance of geographic misses and better parotid sparing was achieved in 3-D plans as compared to TD plans. We could not demonstrate any role for inhomogeneity corrections using currently available computerized dose algorithms.  相似文献   
113.
114.
Imaging of the aging brain. Part I. Normal findings   总被引:1,自引:0,他引:1  
Drayer  BP 《Radiology》1988,166(3):785-796
A thorough knowledge of the normal changes that occur in the brain with age is critical before abnormal findings are analyzed. Magnetic resonance (MR) imaging improves the ability to distinguish normal and abnormal findings in the brain. The major changes that may occur in elderly individuals without neurologic deficits include enlargement of the ventricles, cortical sulci, and vermian subarachnoid spaces; multifocal areas of hyperintensity in the white matter and basal ganglia; a progressive prominence of hypointensity on T2-weighted images of the putamen, almost equal to that of the globus pallidus; an increase in the oxygen extraction ratio with normal or mildly decreased neuron metabolism; arteriosclerosis in large and small arteries and amyloid angiopathy in leptomeningeal cortical vessels; and decreased dopamine receptor binding in the corpus striatum. Since approximately half of the elderly population exhibits only negligible brain alterations, MR imaging may facilitate the distinction between usual (no neurologic dysfunction) and successful (no brain or vascular changes) aging.  相似文献   
115.
This is an update of the Royal Adelaide Hospital radiosurgery experience between November 1993 and December 2004 comprising 165 patients with 168 intracranial lesions. Including re‐treatment, there were 175 treatment episodes (163 radiosurgery and 12 stereotactic radiotherapy) at an average of 1.3 per month. The commonest lesions were acoustic neuroma (65), arteriovenous malformation (58), solitary brain metastasis (23) and meningioma (14). The clinical features, treatment details and outcome are described. Our results continue to be well within the range reported in the published work. Radiosurgery provides an elegant, non‐invasive alternative to neurosurgery and conventional external beam radiotherapy for many benign and malignant brain tumours.  相似文献   
116.
One hundred fifteen patients over 65 years of age were operated on at our institution for coronary artery bypass grafting (CABG). The operative mortality was 5% compared with an overall operative mortality of 2.5% in the last five years for 1,500 persons with CABG. Increased risk factors included qualification for New York Heart Association (NYHA) class IV, ejection fraction of less than 35%, diffuse disease requiring more than five grafts, and age over 75 years. At one year after operation, 81% of the patients were clinically improved, and the survival rate was 91%. Patients over 65 years of age in NYHA classes II and III with good left ventricular function requiring four or less bypass grafts appeared to have an excellent prognosis both acutely and during a one-year follow-up period.  相似文献   
117.
118.
翼核果中蒽醌的研究   总被引:1,自引:0,他引:1  
从翼核果(Ventilago Ieiocarpa Benth.)根中分得四个蒽醌化合物(Ⅰ~Ⅳ)及羽扇豆醇。Ⅲ是第一次从自然界分得。Ⅳ是新化合物,命名为翼核果醌(leiocarpaquinone)  相似文献   
119.
We examined HLA-DR genotype risk in 288 patients with rheumatoid arthritis who were carefully categorized for disease severity. Five hundred ethnically-matched bone-marrow donors were controls. A hierarchy of positive allelic associations was noted with DRB1*0401 (p < 10(-38), *0404,8 (p < 10(-43), *0405 (p < 10(-8), *10 (p < 10(-3) and *0101,2 (p < 10(-2), while DRB1*0403 was negatively associated (p = 0.02). The DRB1 genotype relative risks (and 95% CIs) for RA were: *0404,5,8/*0404,5,8 = 36.2 (15-87), *0401/*0404,5,8 = 31.3 (18-55), *401/*0401 = 18.8 (11-35), *0101,2/*0404,5,8 = 6.0 (2-14), *0101,2/*0401 = 6.4 (3-12), *0101,2/*0101,2 = 1.3 (0.3-6), *10/*0404,5,8 = 27.8 (5-148), *10/*0401 = 20.8 (5-89), *10/*0101,2 = 22.3 (5-96), *0404,5,8/DRX = 5.0 (3-8), *0401/DRX = 4.7 (3-7), *0101,2/DRX = 2.3 (1.4-4), *10/DRX = 3.4 (0.8-14). No significant correlation of DRB1 genotypes was found with severity of RA as judged by nodules or articular erosions.   相似文献   
120.
Posttraumatic stress disorder (PTSD) is a psychological consequence of traumatic work-related hand injury. In the current study, we investigated this relationship by examining the prevalence, of PTSD symptoms in 121 Worker's Compensation patients enrolled in a work rehabilitation program following a wide array of work-related injuries. Eighty-eight men and 33 women, ranging in age from 16 to 78 (M=40.9,SD=10.2), completed the Injury Adjustment Survey, a measure of PTSD symptoms, psychological/behavioral changes following injury, and desire for psychological treatment. We found that the majority of patients reported difficulties sleeping, a diminished sense of future, loss of interest, and increased anger. Twenty percent of patients endorsed symptoms from criteria B (reexperiencing the trauma), C (persistent avoidance or numbing), and D (inreased arousal) for PTSD according to the DSM-IV. PTSD symptoms did not significantly, relate to age, gender, locations of injury, type of injury, seeing the injury occur, or length of time since injury. PTSD symptoms did significantly relate to psychological/behavioral changes or difficulties and the desire to seek psychological treatment. Discussion of the results proceeds from within a psychotraumatological framework. In general, our research confirmed that PTSD symptoms appear to be a clinically significant problem for patients suffering from a variety of work-related injuries.  相似文献   
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