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81.
82.
BackgroundPancreatic pseudolymphoma is extremely rare.MethodWe present multiple pseudolymphomas in the head and body of the pancreas. The hypoechoic lesions observed by endoscopic ultrasound were enhanced in late-phase angio-computed tomography and homogeneously hypointensive in T1-weighted magnetic resonance imaging (MRI). 18F-fluorodeoxyglucose positron emission tomography showed strong accumulation in the lesions. The lesions were suspected to be non-functioning islet cell carcinoma. The intraoperative pathological diagnosis for the specimen obtained by a pylorus-preserving pancreaticoduodenectomy was non-neoplastic lymphoid cells. The remnant lesion in the pancreatic body was preserved.ResultsMacroscopically, the mass was well-circumscribed gray-white colored lesion. The pathological diagnosis was pancreatic pseudolymphoma. The lesion in the remnant pancreas spontaneously disappeared within one year after the operation.ConclusionThe differential diagnosis of pancreatic pseudolymphoma from malignant tumor is very difficult, however, the image findings demonstrated here may be informative. The spontaneous disappearance of pancreatic pseudolymphoma was firstly observed in the present case.  相似文献   
83.
A 16-year-old male with severe thrombocytopenia and progressive multiple organ infarctions was diagnosed as having catastrophic antiphospholipid syndrome (CAPS) complicated with systemic lupus erythematosus, and was successfully treated with combination of anticoagulants, corticosteroids, plasma exchange, and intravenous cyclophosphamide. Antibodies to phosphatidylserine/prothrombin (PS/PT) complex and cardiolipin (CL)/β(2)-glycoprotein?I (β(2)GPI) were simultaneously detected, indicating that the different pathways of both PS/PT and CL/β(2)GPI might be associated with the radical manifestation of CAPS.  相似文献   
84.

Objective

To explore whether synovitis and bone lesions in the wrists and finger joints visualized by plain magnetic resonance imaging (MRI)-based findings correspond exactly or not to those judged by gadolinium-diethylenetriamine pentaacetic acid (Gd-DTPA)-enhanced MRI-based findings.

Methods

Magnetic resonance imaging of the wrists and finger joints of both hands were examined in 51 early-stage rheumatoid arthritis (RA) patients whose median disease duration from the onset of articular manifestations to entry was 5?months, by both plain (T1 and short-time inversion recovery images) and Gd-DTPA-enhanced MRI (post-contrast fat-suppressed T1-weighted images) simultaneously. We focused on 15 sites per hand, to examine the presence of synovitis and bone lesions (bone edema and bone erosion). Gd-DTPA-enhanced MRI-based findings were considered “true” lesions, and we evaluated the accuracy of plain MRI-based findings in comparison to Gd-DTPA-enhanced MRI-based findings.

Results

Synovitis, judged by plain MRI-based findings, appeared as false-positive at pretty frequency; thus, the specificity, positive predictive value and accuracy of the findings were low. The rate of enhancement (E-rate) in false-positive synovitis sites was significantly low compared with true-positive synovitis sites where Gd-DTPA enhancement appears. In contrast to synovitis, the false-positivity of bone lesions, judged by plain MRI-based findings, was very low compared with Gd-DTPA-enhanced MRI-based findings.

Conclusion

Synovitis judged by plain MRI-based findings is sometimes considered false-positive especially in sites where synovitis is mild. However, plain MRI is effective in identifying bone lesions in the wrist and finger joints in early-stage RA.  相似文献   
85.

Background

We retrospectively investigated prognostic factors to be used in selecting the patients with stage IV gastric cancer (GC) who have an unfavorable prognosis after palliative gastrectomy.

Methods

A total of 146 GC patients at stage IV who had undergone palliative gastrectomy were enrolled. Various clinicopathological parameters were evaluated for prognosis.

Results

Surgical morbidity and hospital mortality occurred in 35 (23.9 %) and 4 (2.7 %) patients, respectively. The overall 5-year survival rate and the median survival time were 11.2 % and 13.2 months, respectively. Of the 146 patients, 64 had uncomfortable symptoms associated with GC and 76 had no such symptoms. Of the 64 patients with uncomfortable symptoms, 60 (93.7 %) experienced relief of these symptoms after palliative surgery. Multivariate analysis for patients without uncomfortable symptoms associated with GC revealed that the number of incurable factors and serum SPan-1 level were independent prognostic factors.

Conclusions

Patients with stage IV GC who had multiple incurable factors and a high level of serum SPan-1 might not be candidates for palliative gastrectomy for the purpose of prognostic benefit.  相似文献   
86.
Methamphetamine (METH) is a psychostimulant that damages nigrostriatal dopaminergic terminals, primarily by enhancing dopamine and glutamate release. α1-adrenergic receptor (AR) subtype involved in METH-induced neurotoxicity in rats was investigated using selective α1-AR antagonists. METH neurotoxicity was evaluated by (1) measuring body temperature; (2) determining tyrosine hydroxylase (TH) immunoreactivity levels; (3) examining levels of dopamine and its metabolites; and (4) assessing glial fibrillary acidic protein (GFAP) and microglial immunoreactivity in the striatum. METH caused a decrease in dopamine and TH levels and induced hyperthermia which is an exacerbating factor of METH neurotoxicity. Concurrently, METH increased GFAP expression and the number of activated microglia. Pretreatment with prazosin, a nonselective α1-AR antagonist, completely abolished METH-induced decrease in both dopamine and TH and caused a partial reduction in hyperthermia. Prazosin also prevented METH-induced increase in both GFAP expression and the number of activated microglia. In vivo microdialysis analysis revealed that prazosin, however, does not alter the METH-induced dopamine release in the striatum. The neuroprotective effects of prazosin could be mimicked by a selective α1D antagonist, BMY 7378, but not by selective α1A or α1B antagonists. These results suggest that the α1D-AR is involved in METH-induced hyperthermia and neurotoxicity in rats.  相似文献   
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Established REF52 cells (rat embryo fibroblasts) completely resist stable transformation by ras oncogenes, and simian virus 40 large tumor (T) antigen collaborates with ras to convert REF52 cells to tumorigenic state. A temperature-sensitive simian virus 40 large T antigen (encoded by tsA58) allowed the T24 Ha-ras oncogene to transform REF52 cells in a temperature-dependent manner. Two thirds of the clones transformed with tsA58 and ras became arrested in G2 or late S phase when shifted to a nonpermissive temperature for T antigen stability. Thus, ras induced growth arrest rather than stable transformation in the absence of a functional collaborating oncogene. These results indicate that collaborating oncogenes can regulate cellular responses to ras and have implications regarding therapeutic strategies to control tumor cells expressing activated ras oncogenes.  相似文献   
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