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81.
During computed tomography (CT) pelvimetry of two pregnant women, bony abnormalities of the fetuses were noted on the scout images that were not confirmed at delivery. To explore the cause of these artifacts, specimen long bones were manipulated in various ways during CT scout imaging. Artifacts like those seen during in vivo imaging were found to be caused by motion of the object. The CT scout view is an example of an image produced by a digital system that uses a scanning beam. This type of digital system is being used for several types of body imaging including screening for scoliosis and chest radiography. Attention to motion artifacts should decrease diagnostic errors and aid further development of these systems. 相似文献
82.
83.
羽叶三七叶中甙类成分的研究 总被引:3,自引:0,他引:3
从羽叶三七叶中分离到十三种甙类成分,经FAB-MS,13CNMR谱,双照射1HN-MR谱,1H-1H COSY谱及与标准品直接对照,证明十一种为已知化合物,分别为人参皂甙F1(Ⅰ),F2(Ⅱ),F3(Ⅲ),Rg2(Ⅳ),Ra(Ⅴ),Rd(Ⅵ),Rb1(Ⅷ),Rb3(Ⅷ),24(S)-假人参甙F11(Ⅸ),人参黄酮(Ⅹ)和珠子参甙F1(Ⅺ);另外两种为新的达玛烷型皂甙,命名为羽叶三七甙F1(Ⅻ)和F2(ⅫⅠ),并确定其化学结构。同时修正珠子参甙F3的结构。进一步阐明人参黄酮甙结构中的两个糖的连接方式。 相似文献
84.
Over the past 7 years, eight patients with splanchnic artery aneurysms and pseudoaneurysms were studied and treated. Transcatheter embolization resulted in occlusion of the lesions in all eight patients. Potentially risky and difficult surgery was avoided completely in four patients. Three patients had elective surgery at a later date when their condition was more stable. The remaining patient had definitive surgery after embolization. Transcatheter embolization should be the initial treatment of choice in splanchnic artery aneurysms and pseudoaneurysms. 相似文献
85.
Bone marrow disorders: characterization with quantitative MR imaging 总被引:10,自引:0,他引:10
Thirty patients with various hematologic disorders and 15 healthy control subjects underwent quantitative magnetic resonance (MR) imaging of the lumbar spine with spin-echo techniques. Images of patients with infiltrative bone marrow disorders showed significantly more prolonged T1 times than those of control subjects (P less than .001). It was not possible to distinguish different diffuse infiltrative bone marrow disorders on the basis of T1 values. Aplastic anemia could be distinguished from normality because of significantly shortened T1 (P less than .001). A significant correlation was seen between T1 and bone marrow cellularity (r = .74, P less than .001). T2 was of no value in the characterization of bone marrow disorders. Quantitative MR imaging dose not improve the diagnostic potential of bone marrow imaging in the detection of diffuse marrow infiltrates. 相似文献
86.
Murakami T; Baron RL; Peterson MS; Oliver JH rd; Davis PL; Confer SR; Federle MP 《Radiology》1996,200(1):69
87.
The elbow: MR features of nerve disorders 总被引:3,自引:0,他引:3
88.
Recruitment and screening policies and procedures used to establish a paid donor oocyte registry 总被引:3,自引:2,他引:1
We have reviewed the demographic characteristics of, and report
abnormalities noted in, the de-novo growth and development of a paid oocyte
donation programme. The personal profiles of all prospective oocyte donors
were reviewed. Acceptance or rejection of candidates was based upon
screening the results of medical, genetic and psychological testing. A
total of 603 candidates initially responded to our advertisement. From this
pool, 313 individuals were considered suitable and contacted by telephone.
Following further conversation, 176 women were scheduled an entry
interview. On completion of the formal screening process, 17.6% (n = 31) of
those actually interviewed were denied entry. Thus, from the initial
interested parties, only 23% of women wishing to participate in oocyte
donation were considered suitable candidates. Given the high attrition
rate, we concluded that the need for rigorous and thorough medical,
psychological and genetic testing is mandatory for the establishment of a
donor registry. Furthermore, professional counselling of prospective donors
with respect to the results of tests and the implications of test results
with respect to their future medical and reproductive health, are important
parts of providing comprehensive care.
相似文献
89.
d,l-15(R)-15-Methyl-PGF2α methyl ester 11-trimethylsilyl ether(II)wasprepared from selective monosilylation of d,l-15(R)-15-methyl-PGF2αmethyl ester(I) withtrimethylsilyldiethylamine in acetone. Oxidation of(II ) with Collin's reagent gave d,l-15(R)-15-methyl-PGE2 methyl ester 11-trimethylsilyl ether(III)which,without purification,was converted to d,l-15(R)-15-methyl-PGE2 methyl ester(IV)under mild acidic conditions. 相似文献
90.