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741.
742.
Intravascular foreign bodies: percutaneous retrieval 总被引:9,自引:0,他引:9
Percutaneous retrieval of an intravascular foreign body was performed in 20 patients. There were 14 through-the-needle intravenous catheter fragments. In four patients the embolized foreign body was a broken diagnostic catheter. One patient had a ventriculovenous broken catheter and another patient had a bullet in the pulmonary circulation. Eight foreign bodies were located in the superior vena cava, six in the pulmonary artery, two in the right side of the heart, one in the subclavian vein, one in the thoracic aorta, and two in the aortoiliac segment. Percutaneous retrieval was successful in 95% of the attempts. In one case the procedure was performed to dislodge the foreign body into a better position for surgical retrieval. 相似文献
743.
Luciana?AC?MachadoEmail author Chris?G?Maher Rob?D?Herbert Helen?Clare James?McAuley 《BMC musculoskeletal disorders》2005,6(1):50
Background
Low back pain (LBP) is a major health problem. Effective treatment of acute LBP is important because it prevents patients from developing chronic LBP, the stage of LBP that requires costly and more complex treatment. 相似文献744.
T Maddess PhD S Bedford BSc AC James PhD KA Rose PhD 《Clinical & experimental ophthalmology》1997,25(4):94-97
It has been proposed that the spatial frequency doubled (FD) illusion may originate from Y-like non-linear retinal ganglion cells. If the contrast of multi-frequency stimuli is increased, Y cells show a phase advance in the self-sum frequencies but not in other output frequencies. We looked for these effects with a multi-region pattern electroretinogram (PER.G) displaying the sum of two temporal frequencies in each visual field location. Regional variation was found in the recorded sum and difference frequencies. The results indicate that PERG signals become dominated by responses from Y-like cells when the FD illusion is seen. 相似文献
745.
746.
Allen AC; Topham PS; Harper SJ; Feehally J 《Nephrology, dialysis, transplantation》1997,12(4):701-706
BACKGROUND: Reduced galactosylation of the O-linked glycans of the IgA1
hinge region in IgAN has recently been described. To investigate the
underlying defect resulting in this abnormality, we have measured the
activity of beta 1,3 galactosyltransferase, the enzyme responsible for
galactosylation of O-linked sugars. METHODS: A galactose-acceptor substrate
was prepared from degalactosylated hinge region fragments of normal IgA1,
and incubated with the T cell, B cell, and monocyte lysates from patients
with IgAN and controls for acceptor regalactosylation. The extent of
acceptor galactosylation was then measured with biotinylated Vicia villosa
lectin (VV), which is specific for ungalactosylated moieties. Lectin
binding of serum IgA from the same subjects was also measured. RESULTS: T
cell and monocyte beta 1,3 galactosyltransferase activities did not differ
between IgAN and control, but B cell lysates in IgAN showed significantly
lower beta 1,3 galactosyltransferase activity than control (6.2 +/- 0.71
vs. 9.5 +/- 1.03 AU/microgram, P = 0.018). Furthermore, B cell beta 1,3
galactosyltransferase activity showed a negative correlation (r = - 0.87, P
= 0.002) with VV lectin binding of serum IgA in IgAN, but not controls.
CONCLUSIONS: These data indicate that altered IgA1 O- galactosylation in
IgAN results from a B cell-restricted reduction of beta 1,3
galactosyltransferase activity. This enzyme defect may be a fundamental
pathogenic abnormality in IgAN.
相似文献
747.
Kushner DC; Cleveland RH; Herman TE; McLoud TC; Waltman AC; Shepard JA; Dedrick CG; Kopans DB; Greene RE 《Radiology》1987,163(3):685-688
Standard film examinations of the chest were compared with low-dose flying spot digital radiographic examinations obtained with a prototype unit in 174 patients. Analysis of pooled data from a double-blind study of 120 patients showed that film was more sensitive than digital images in the detection of pulmonary parenchymal abnormalities, that is, abnormal opacities, atelectasis, scar, and interstitial lung disease (P less than .05). Analysis of pooled data from a side-by-side study of 54 patients showed that the digital images were more sensitive than film in the detection of normal mediastinal and pleural soft-tissue contours, including the azygoesophageal recess, paraspinal line, and vertebral disk spaces (P less than .05). However, film was more sensitive than digital images in the detection of abnormalities of the lung, including scar, interstitial lung disease, septal lines, and the presence of vascular catheters (P less than .05). These findings suggest that low-dose flying spot digital radiography of the chest, as performed with this specific prototype unit, is not adequate to replace film in the detection of abnormalities of the lung parenchyma. 相似文献
748.
749.
750.