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81.
Multislice spiral CT(MSCT)has recently e-volved as a modalityfor non-invasive coronaryi ma-ging.16-slice MSCT allows excellent distal coro-nary coverage with higer temporal and spatial reso-lution.It can be usedto detect stenosis of coronaryartery with a diameter≥1.5cm[1,2].We investi-gated a group of coronary MSCT angiography(MSCTA)results,with those of selective X-raycoronary angiography(SCA)serving as the refer-ence standard.1MATERIALS AND METHODS1.1PatientsBetween July20…  相似文献   
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空气喷磨对预防性树脂充填微渗漏的影响   总被引:1,自引:1,他引:0  
目的 :体外评价空气喷磨、酸蚀和两者结合对预防性树脂充填微渗漏的影响。方法 :对照组 (I,n =12 )对人离体磨牙常规预防性树脂充填。其余组分别用 5 0 μ(Ⅱ,Ⅲ)和 27μ(Ⅳ ,Ⅴ)氧化铝喷磨 ,其中两组 (Ⅳ ,Ⅴ)酸蚀 30s。每组一半牙齿进行热循环处理 (5~ 5 5℃ ,2500周 )后 ,用亚甲基蓝溶液着色。结果 :不论结合酸蚀与否 ,用 5 0 μ氧化铝喷磨 ,均与对照组不存在显著性差异 (p >0.05)。但喷磨后酸蚀比单纯喷磨能显著地减少微渗漏 (p<0.05)。 5 0 μ较 27μ氧化铝微粒显著地减少微渗漏(p <0.05)。结论 :空气喷磨结合酸蚀能显著地减少预防性树脂充填的微渗漏。  相似文献   
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cIMPACT‐NOW (the Consortium to Inform Molecular and Practical Approaches to CNS Tumor Taxonomy) was established to evaluate and make practical recommendations on recent advances in the field of CNS tumor classification, particularly in light of the rapid progress in molecular insights into these neoplasms. For Round 2 of its deliberations, cIMPACT‐NOW Working Committee 3 was reconstituted and convened in Utrecht, The Netherlands, for a meeting designed to review putative new CNS tumor types in advance of any future World Health Organization meeting on CNS tumor classification. In preparatory activities for the meeting and at the actual meeting, a list of possible entities was assembled and each type and subtype debated. Working Committee 3 recommended that a substantial number of newly recognized types and subtypes should be considered for inclusion in future CNS tumor classifications. In addition, the group endorsed a number of principles—relating to classification categories, approaches to classification, nomenclature, and grading—that the group hopes will also inform the future classification of CNS neoplasms.  相似文献   
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The development of antibodies to factor VIII (inhibitors) in response to clotting-factor concentrates administration in hemophilia is common during the first few years of treatment but rare in multitransfused patients. We have investigated the possible association of a recently introduced factor VIII concentrate (Factor VIII CPS-P) in The Netherlands with the occurrence of inhibitors. To this effect, we conducted two studies. First, we performed a national multicenter study in which clinical information and inhibitor test results were obtained for 447 hemophilia A patients over the period 1988 through 1991. Secondly, for a baseline comparison we estimated the frequency of inhibitor development in a closely followed cohort of 144 patients, from 1984 through 1989. Before the introduction of Factor VIII CPS-P, the incidence of new inhibitors was 4.4/1,000 patient-years in the national study from March 1988 through May 1990, and 3.9/1,000 patient- years in the cohort followed from 1984 through 1989. These figures are similar to the incidence of new inhibitors that was found in a large cohort of patients in the United States followed in the 1970s. In the period that the new concentrate Factor VIII CPS-P was on the market, from June 1990 through November 1991, 11 clinically relevant inhibitors were detected, which yielded an incidence over this interval of 20.1/1,000 patient-years, a 4.5-fold increase compared with the previous interval (C195: 1.4 to 14.3). Nine of these 11 patients had in their lifetime received over 250 infusions with factor VIII preparations. whereas all of the inhibitors detected in the previous time interval, and all of the 24 inhibitor patients described in the US study, had received less than 250 infusions in their lifetime. All patients who developed inhibitors after June 1990 had been exposed to Factor VIII CPS-P, whereas only 75% of the patients who did not develop an inhibitor had been exposed to this product. In a prospective extension of the study, with a second inhibitor measurement after 3 months, we found that one additional inhibitor had developed during 52.5 patient-years of Factor VIII CPS-P use. In conclusion, there has been a sudden increase in the frequency of inhibitor patients, for a large part among multitransfused patients. It seems more than likely that this increase is associated with the introduction of a new factor VIII concentrate in The Netherlands.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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Mankovich  NJ; Taira  RK; Cho  PS; Huang  HK 《Radiology》1988,167(1):139-142
A digital optical disk archive for storage of computed radiographic, computed tomographic, magnetic resonance, ultrasonographic, and digitized film radiographic images was installed. In the system, digital images enter a minicomputer, are temporarily stored on magnetic disks, and are archived onto write-once read-many optical disks at their full resolution. A pictorial index of minified images is maintained for each patient. After 8 months of operation, 49,400 megabytes of images had been retained on 19 optical disks stored, after January 1987, in a mechanical jukebox-style optical disk library. The success rate for archival capture of images during the initial period was 96.6%. The failures were due to overfilling of the magnetic disk, a problem addressed through the addition of a second magnetic disk unit. There were no medium-related image errors during the early period. Problems resulting from the slow speed of optical disk systems were addressed operationally by initiating recall of a patient's archived images from the optical to the faster magnetic disk as soon as the system received a request to acquire a new image. Also, optical disk retrieval times are expected to improve with technologic development.  相似文献   
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