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81.
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The histologic features of thymuses from three patients who underwent thymectomy for acute lymphoblastic leukemia or lymphoblastic lymphoma in complete clinical remission are described. The thymuses from all three patients were fibrotic with a variability in the appearance of the lobules. Some of the lobules consisted predominantly of epithelial cells with small numbers of mature appearing lymphocytes, while other lobules were expanded and composed predominantly of cells having morphological features of immature lymphoid cells consistent with residual or recurrent disease.  相似文献   
83.
GOALS: The purpose of this review is to look at the evidence presented in the literature on the immunoexpression of p27 in cancers of the gastrointestinal tract and liver. BACKGROUND: Cell cycle proteins have been shown to play an important role in the oncogenesis of many tumors. Several of these proteins have been examined in concert and in isolation, and some have been put forward as putative tumor markers. p27, which is an important inhibitory protein in the cell cycle and belonging to a group of cyclin-dependent kinase inhibitors, has also been studied in several malignancies, most notably breast, lung, bladder, and prostate cancers. Considerable work has also been done on the expression of this protein in cancers occurring within the gastrointestinal tract. RESULTS: Cancers occurring in the major sites of the gastrointestinal tract (esophagus, stomach, and colorectum) and liver show a similar pattern with regard to p27 protein levels. p27 emerges as a statistically significant predictor of survival and tumor behavior. It has been suggested that p27 loss occurs early in the carcinogenesis process, with dysplastic epithelium having decreased expression. The more aggressive, metastasizing cancers tend to lack p27 expression as well. Some studies have also invoked the subcellular localization of p27 (cytoplasmic versus nuclear) as also being of prognostic value. CONCLUSION: Therefore, in gastrointestinal and hepatic cancers, low p27 expression is regarded as an important adverse prognostic factor.  相似文献   
84.
A pilot study was conducted to investigate the osteogenic potential of autogenous cancellous-marrow grafts placed in irradiated tissue. Three dogs received 4,100 rads in ten treatments ooer 32 days. Postirradiation discontinuity mandibular defects were created. These defects were restored with cancellous-marrow autogenous bone supported in position by a titanium mesh basket. Bony union occurred in all the mandibles. The titanium mesh partially eroded through the oral mucosa in two animals. The quantity of new bone formed in the surgical defect varied. Two dogs had complete restoration of the resected mandible. Histologic observations were documented in both the graft area and the surgically uninvolved contralateral side of the mandible.  相似文献   
85.
L-carnitine and its esters (acetyl-L-carnitine and propionyl-L-carnitine) at pharmacological doses (1, 5 and 10 mM) are absorbed by the rat jejunum by simple diffusion. Partition coefficients of carnitine esters determined in lipophilic media (diethyl ether/water and olive oil/water) are greater than that of L-carnitine. It would therefore seem that esters diffuse more easily through the lipid component of the intestinal barrier. The transport of acetyl- and propionyl-L-carnitine at pharmacological doses seems to be linearly and positively correlated with K+ transport but not with Na+ transport.  相似文献   
86.
Recurrent pulmonary embolism after Greenfield filter placement   总被引:1,自引:0,他引:1  
Geisinger  MA; Zelch  MG; Risius  B 《Radiology》1987,165(2):383-384
Three patients with documented recurrent pulmonary embolism with an inferior vena cava (IVC) Greenfield filter in place were examined with contrast-material-enhanced cavography. Mechanisms for recurrent pulmonary embolism were found to be propagation of thrombus through the filter struts, occlusion of the IVC at the level of the filter, and loss of contact of the filter hooks with a portion of the caval wall.  相似文献   
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Hamlin  JA; Friedman  M; Stein  MG; Bray  JF 《Radiology》1986,158(1):199-202
We have reviewed our experience with 118 biliary catheterization procedures in 109 patients from 1979 to 1984. Major complications (septic shock, hemorrhage, subphrenic abscess, and formation of an arteriovenous fistula) occurred in five patients (4.2%), three of whom died (2.5%). Minor complications occurred in 41 patients. Our success rate using the procedure was 97%. The complications that occurred are described.  相似文献   
90.
The topography of scalp SEPs to mixed and sensory median nerve (MN) and to musculocutaneous nerve stimulation was examined in 20 healthy subjects through multichannel (12-36) recording in a 50 msec post-stimulus epoch. MN-SEPs in both frontal leads were characterized by an N18, P20, N24, P28 complex showing maximal amplitude at contralateral parasagittal sites. This was sometimes partly obscured by a wide wave N30 having a fixed latency, but a steep amplitude gradient moving toward the scalp vertex. A P40 component followed, having longer peak latencies, moving the recording sites from contralateral medial parietal toward the vertex and frontal ipsilateral positions. MN-SEPs in contralateral parietal leads contained a widespread N20 with a maximum source posterior to the Cz-ear line. The following P25 enveloped two subcomponents - early and late P25 - having different distributions. The late P25 showed a maximum - coincident with that of wave N20 - which was localized more posteriorly than that of the early P25. An inconstant wave N33 with progressively longer peak latencies from sagittal toward lateral positions was then recorded. MN-SEPs in contralateral central positions showed a well-localized P22 wave in which both the parietal early P25 and the frontal P20 were vanishing. Common or separate generators for frontal, central and parietal SEPs were discriminated by evaluating the influence of stimulus rate and intensity, as well as of general anesthesia and transient CBF deficits, investigated in 7 patients undergoing carotid endarterectomy. Unifocal anodal threshold shocks were separately delivered to each of the scalp electrodes and motor action potentials were recorded from the target muscle in order to delineate the scalp representation of the motor strip for the upper limb and, consequently, to monitor, through SEP tracings, the short-latency sensory input to the motor cortex for hand and shoulder muscles. This was characterized by a boundary zone separating the parietal N20-early P25 complex, from the fronto-central N18-P22 one. This zone had an oblique direction strongly resembling that of the central sulcus.  相似文献   
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