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Jaffe  RB; Orsmond  GS; Veasy  LG 《Radiology》1986,161(2):355-357
In five patients, aged 4 days to 20 months, the left pulmonary artery was inadvertently ligated at the time of attempted closure of the patent ductus arteriosus. The complication was recognized in these patients between 1 day and 5 years later from findings of chest radiography, two-dimensional echocardiography with spectral analysis of Doppler shifted echoes, and angiography. In three patients, the presence of asymmetric pulmonary blood flow on chest radiographs obtained after surgery initially suggested the diagnosis. In the other two patients with bronchopulmonary dysplasia, the diagnosis was made by means of two-dimensional echocardiography and Doppler spectra in one and angiography in the other. On angiograms, the left pulmonary artery distal to the ligation was visualized by delayed opacification from aortic collaterals in three patients and by means of pulmonary venous wedge injection in one. Radiographic and echocardiographic examination with Doppler spectra may permit prompt diagnosis and early correction of this complication.  相似文献   
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Head and neck lesions: MR-guided aspiration biopsy   总被引:1,自引:0,他引:1  
Aspiration biopsy guided with computed tomography (CT) has long been a valuable tool in the evaluation of head and neck disease. The ability to obtain diagnoses without the need for surgery has had a significant effect on patient treatment. Magnetic resonance (MR) imaging is now rapidly replacing CT as the primary imaging study for many head and neck diseases. The standard stainless steel needles used for CT-guided biopsy are unsuitable for MR-guided biopsy because significant ferromagnetic artifacts obscure the underlying anatomy. A new needle has recently been designed specifically for use with MR imaging. This needle has far less magnetic susceptibility and therefore does not cause significant image distortion. The authors describe the use of this needle in MR-guided aspiration biopsy of a variety of lesions in the head and neck.  相似文献   
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Tongue and oropharynx: findings on MR imaging   总被引:6,自引:0,他引:6  
Ten healthy subjects and 44 patients with diseases of the tongue or oropharynx were studied with magnetic resonance (MR) imaging. Axial, coronal, and sagittal images with a thickness of 4 mm were obtained with a pixel size of 0.75 X 0.75 mm on a 256 matrix. Nineteen of the patients underwent computed tomography (CT). Nine of those patients later had surgery, and the specimens were obtained for organ sectioning. These three studies as well as clinical history and physical examination findings were correlated. MR imaging was equal to or better than CT in those patients having both examinations. However, neither CT nor MR allowed recognition of histologic features or detection of microscopic spread of disease. Direct coronal and sagittal imaging planes on MR imaging allowed visualization of intrinsic tongue musculature, not possible with CT; this was important in recognizing subtle tumor extension. For these reasons, MR is the imaging method of choice for studying diseases of the tongue and oropharynx.  相似文献   
45.
Effacement of the fetal cisterna magna in association with myelomeningocele   总被引:2,自引:0,他引:2  
Goldstein  RB; Podrasky  AE; Filly  RA; Callen  PW 《Radiology》1989,172(2):409-413
The cisterna magna is effaced in association with myelomeningocele. The authors retrospectively investigated the size of the fetal cisterna magna as a predictor of fetal myelomeningocele in 67 pregnant women (17-38 menstrual weeks) referred for prenatal sonography because of an elevated serum alpha-fetoprotein level (n = 61) or a suspicion of fetal ventriculomegaly on previously obtained sonograms (n = 6). Twenty fetuses had myelomeningocele, 14 had isolated ventriculomegaly, and 33 were normal. A normal-sized cisterna magna (range, 4-9 mm in depth) was present in all normal fetuses. In 19 of 20 fetuses with myelomeningocele, the views of the posterior fossa were adequate, and in each of these the cisterna magna was effaced (n = 18) or very small (n = 1). The cisterna magna was effaced in five of 13 (38%) fetuses with isolated ventriculomegaly in whom the posterior fossa was adequately imaged. Although effacement of the cisterna magna is a nonspecific finding, the high negative predictive value of this sign is useful during routine screening of the fetal neural axis.  相似文献   
46.
A modified Western blot (WB) that includes both shared (r21e) and unique recombinant envelope proteins from human T-lymphotropic virus (HTLV) type I (rgp46I) and type II (rgp46II) was compared to conventional HTLV serologic tests in 379 United States blood donors and individuals residing in diverse geographic regions, and the specimens were categorized as positive (n = 158), indeterminate (n = 158), or negative (n = 63) for HTLV infection. Of the 158 HTLV-I/II-positive specimens (66 requiring radioimmunoprecipitation assay [RIPA] for confirmation), 156 reacted concordantly with r21e, gag, and either rgp46I or rgp46II, thus eliminating the need for RIPA in all but two specimens and yielding a test sensitivity of 98.7 percent. Of the 158 indeterminate and 63 negative specimens, none reacted with r21e and rgp46I or rgp46II, yielding a test specificity of 100 percent. Furthermore, analysis of an additional 184 consecutive specimens from a retrovirology reference laboratory demonstrated that the modified WB correctly identified 27 of 28 HTLV-I specimens and all 13 HTLV-II specimens, with a test sensitivity of 97.6 percent. None of specimens that were indeterminate or nonreactive in conventional WB and/or RIPA and none of the screening enzyme immunoassay-negative specimens reacted with r21e and either rgp46I or rgp46II, for a test specificity of 100 percent. Thus, the modified WB appears to be highly sensitive and specific for simultaneous detection and discrimination of HTLV-I from HTLV-II and has the advantage of being a one-step assay that is easily performed in all types of laboratory settings and allows rapid, reliable, and standardized testing for HTLV-I/II infection.  相似文献   
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BACKGROUND: JMH is a high-frequency red cell blood group antigen that resides on a 76- to 80-kDa glycosylphosphatidylinositol-linked protein also known as CDw108. Antibodies with JMH specificity are often autoimmune and are usually, if not always, clinically benign. Some individuals with JMH-variant antigen produce alloantibodies to JMH, but little evidence concerning their clinical significance is available. This article reports on two patients who express a JMH-variant antigen and produced alloanti-JMH. STUDY DESIGN AND METHODS: Murine monoclonal antibodies and human antibodies to JMH were used in hemagglutination, radioimmunoassay, and Western blot testing of red cells from two JMH- variant patients; antiserum from one of these patients was also used in biochemical studies. In addition, in vivo survival of JMH-positive red cells was studied in the same patient. RESULTS: Biochemically, both examples of red cells with the JMH-variant phenotype expressed a JMH protein with a molecular weight similar to that of the normal JMH protein. For both patients, family studies suggested an autosomal recessive pattern of inheritance. Survival study demonstrated reduced in vivo red cell survival in one patient. CONCLUSION: JMH-variant phenotypes express a protein of normal molecular weight and are inherited in an autosomal recessive pattern. Furthermore, individuals with this phenotype can produce clinically significant antibodies.  相似文献   
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