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21.
MacEwan  DW 《Radiology》1987,163(2):559-563
Eleven radiologists appointed by the major radiological societies participated for the past 5 years in the development of the Health Policy Agenda for the American People. The Agenda is an action plan to address a wide variety of serious problems in medicine. The first phase involved establishment of 159 principles, broad value statements that were the foundation of the project. Phase 2 involved the development of policy proposals on 38 urgent issues for action in medical science; education; health resources; delivery mechanisms; evaluation, assessment, and control; and payment for services. These proposals are summarized in this report. The activities and recommendations of representatives for the field of radiology are described. The Agenda has been released, and an implementation phase has begun. It will likely be of great importance to the practice of radiology over the next decade. Important issues can be addressed by acting with the coalitions that are being formed from among the more than 150 participating organizations.  相似文献   
22.
Meniscal tears of the knee: accuracy of MR imaging   总被引:39,自引:0,他引:39  
Crues  JV  d; Mink  J; Levy  TL; Lotysch  M; Stoller  DW 《Radiology》1987,164(2):445-448
Before surgery, 277 menisci in 144 knees were examined with magnetic resonance (MR) imaging. They were then examined directly with arthroscopy or arthrotomy. Menisci were graded on a scale of 1-3 according to the character of the intrameniscal MR imaging signal. At surgery, 137 of 154 (89%) menisci exhibiting only grade 1 or grade 2 signal were found to be normal. One hundred sixteen of 123 (94%) menisci exhibiting intrameniscal signal communicating with a meniscal articular surface (grade 3 signal) had tears. If only a grade 3 signal is considered consistent with meniscal tears, then MR findings and surgical findings agreed in 91.3% of menisci. MR imaging can separate surgically significant from nonsignificant meniscal lesions and is useful in the noninvasive preoperative screening of suspected meniscal tears.  相似文献   
23.
Surface shield: device to reduce personnel radiation exposure   总被引:2,自引:0,他引:2  
A simple device is described that can reduce personnel exposure from scatter radiation by up to 75%. The device consists of an oblong piece of shielding (0.75-mm lead equivalent) that is taped to the side of the patient during percutaneous renal stone removal and other interventional procedures. Contrary to other shields and barriers, this does not interfere with access to the patient. Scatter exposure data from phantom studies are presented and the rationale for surface shielding discussed.  相似文献   
24.
Kapila  A; Chakeres  DW 《Radiology》1986,160(1):265-267
A new technique has been designed to improve myelography examinations of the entire lumbar spinal canal in patients with severe spinal stenosis using a single needle puncture. When a high-grade obstruction to the caudal flow of contrast material is encountered, the patient is placed in a flexed sitting position for 1 minute. This technique was performed in eight patients with severe lumbar spinal stenosis. It successfully helped depict the lower lumbosacral canal below an apparently complete block in four patients and resulted in improved visualization of the lower sac in four patients with partial block.  相似文献   
25.
Urine-compatible polymer for long-term ureteral stenting   总被引:1,自引:0,他引:1  
Internal double-J ureteral stents were designed from a urine-compatible polymer (C-Flex), and 35 stents were placed in patients. The overall patency rate for the stents was 80%, with most stent failures occurring before 2 months; the follow-up period ranged from 2 to 16 months, with a mean follow-up for all stents of 5.0 months. Stents were considered patent at last follow-up only if they had been in place for at least 2 months. No migration or fracture of the stents occurred. Physical properties of urine-exposed stents were compared with those of virgin tubing and tubing exposed for 1 year to shelf conditions. Stent patency was optimized by increasing urine flow by increasing the patient's voluntary oral intake, administering prophylactic oral antibiotics, and avoiding placement of stents into grossly bloody or infected collecting systems.  相似文献   
26.
Undiagnosed chronic Lyme disease caused by Borrelia burgdorferi is considered a differential diagnoses in medically unexplained symptoms like arthralgias, distal paresthesias, depressive symptoms, lack of concentration and fatigue. The aims of the study were to assess the association of mental and physical complaints with seropositivity for anti-Borrelia IgG in a general population sample. Seropositivity indicated an infection with Borrelia in the past. The Study of Health in Pomerania was conducted in a community living in a region with endemic Lyme disease. Mental and physical complaints were assessed on 38 items with the von Zerssen's complaint scale. IgG antibodies to Borrelia were determined by ELISA in 4264 individuals. Seropositivity was analyzed applying two cut-off scores (>5 and >10 IU/ml). IgG antibodies to Borrelia were found positive in 388 subjects (9.1%) applying the >5 IU/ml cut-off and in 130 subjects (3.0%) applying the >10 IU/ml cut-off. In multivariate analyses (MANCOVA), both definitions of seropositivity were not associated with increased mental or physical complaints while adjusting for gender, age, employment status, rural residency, physical activity, diabetes mellitus and number of chronic diseases. In the general population, seropositivity for anti-Borrelia IgG antibodies was not associated with an increase of self-rated mental or physical complaints or impairments. Therefore, clinicians should not overvalue seropositivity for anti-Borrelia IgG as a medical cause for unexplained mental or physical complaints.  相似文献   
27.
牛津膝置换是使用最广泛的膝关节单髁置换(UKR)。牛津膝在37年前开始应用,拥有一个全匹配的活动衬垫,因而磨损率非常低。牛津膝最主要的使用指征是膝关节前内侧骨关节炎,这种病人至少占所有需要行膝关节置换术患者的50%。由于这一系统的设计特点,传统UKR的反指征,如年龄、活动量、肥胖、髌股关节损害和软骨钙质沉着症等对于牛津膝均不是反指征。与全膝关节置换(TKR)相比,牛津膝提供更快的康复、更好的功能、更大的活动度和更好的术后满意度,发生并发症更少、程度更轻,病残率和死亡率更低。一个持续超过30年的研究显示在90%的病例中,牛津膝为患者终生提供了优或良的临床结果,且不需要翻修。在最近15年,牛津膝通过微创手术入路植入,涉及6000多例使用该入路牛津膝置换的9个研究报道显示,10年生存率约95%。在许多这样的研究中,医生们在拟行膝关节置换的患者中约50%使用了牛津单髁膝置换。  相似文献   
28.
29.
A clonally distinct recurrence of Burkitt's lymphoma at 15 years   总被引:2,自引:0,他引:2  
Lister  J; Miklos  JA; Swerdlow  SH; Bahler  DW 《Blood》1996,88(4):1407-1410
A human immunodeficiency virus-negative male was successfully treated for two occurrences of Burkitt's lymphoma, 15 years apart. As consolidation of his second remission, he underwent high-dose chemotherapy with peripheral blood stem cell transplantation. In an effort to prove whether the second lymphoma was a relapse of the first or a second primary lymphoma, we obtained paraffin-embedded material from both lymphomas. DNA was extracted from this material and amplified by polymerase chain reaction (PCR) using consensus JH and VH region primers. Analysis of the PCR products, which mostly reflects VDJ joints, showed two sharp bands of different molecular size, proving the monoclonal nature of the lymphomas and suggesting that each had different Ig gene rearrangements. Sequencing of both PCR products showed a marked dissimilarity in nucleotide sequence in the clonally unique VDJ joint region, providing strong evidence for the separate cellular genesis of each lymphoma. These results suggest that late relapses of Burkitt's lymphoma should be examined for clonal distinctiveness. If the second lymphoma is distinct from the primary one, it might be treated as a primary lymphoma rather than as recurrent disease.  相似文献   
30.
Yeung  HN; Kormos  DW; Sebok  DA 《Radiology》1988,167(2):537-540
A method for separating binary chemical-shift components with a single image data acquisition by means of stimulated echoes is demonstrated. With a strategy analogous to the modified Dixon method, three stimulated echoes were acquired to form three complex images. In each of the images, the complex pixel intensities were imparted, by design of the pulse sequence, with a phase factor carrying chemical-shift or field inhomogeneity information. With these three images, true fat/water separation can be obtained in biologic tissues. Studies at high field strength (4.7 T) on a toluene phantom, a pseudo-binary chemical-shift system, were used to evaluate the applicability of the method. Its clinical feasibility was demonstrated on a healthy human subject in a 0.6-T whole-body imaging system.  相似文献   
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