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排序方式: 共有392条查询结果,搜索用时 31 毫秒
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Neuroimaging in Pineal Tumors 总被引:4,自引:0,他引:4
F Reis MD AV Faria MD PhD VA Zanardi MD PhD JR Menezes MD F Cendes MD PhD LS Queiroz MD PhD 《Journal of neuroimaging》2006,16(1):52-58
BACKGROUND AND PURPOSE: The authors report radiological findings in 11 tumors in the pineal region, which were histologically diagnosed as germinomas, pineocytomas pineoblastomas, ependymomas, teratomas, and astrocytomas. METHODS: Computed tomography (CT) was performed in seven patients and magnetic resonance imaging (MRI) was performed in all patients. RESULTS: CT showed a solid or solid/cystic mass with variable contrast enhancement. MRI showed a heterogeneous mass, with hypointense signal on T1 and iso/hyperintense signal on T2-weighted images (WI) and gadolinium enhancement. Extension to adjacent structures occurred in five patients and spread through the cerebral spinal fluid (CSF) in two. CONCLUSIONS: Pineal region tumors have no pathognomonic imaging pattern. MRI and CT are complementary in diagnosis and are important to determine localization, extension, and meningeal spread. 相似文献
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Cell culture-based transdominant genetic techniques provide new methods for discovering peptide/RNA modulators of cellular pathways. We applied this technology to isolate a peptide inhibitor of human rhinovirus. A green fluorescent protein (GFP)-scaffolded library of cDNA fragments was expressed in HeLa cells from a retroviral vector and screened for inhibitors of rhinovirus-mediated cell killing. A DNA clone, I421, increased cell survival in an HRV14 challenge assay from less than 0.5% to greater than 60%. It encodes a 53-amino-acid C-terminal extension of the GFP scaffold. Particular subclones of Hela cells expressing I421 (exemplified by I421dp3) show a delay in virus production and a 50-fold decrease in viral RNA levels at 6-8 h postinfection. HRV2, HRV14, and HRV16 show a dramatic decrease in plaque-forming ability on I421dp3 while Coxsackievirus B3 showed a small reduction. Levels of ICAM-1, the receptor for the main rhinovirus serotype, are not altered in I421dp3. 相似文献
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Page MJ Poritz LS Tilberg AF Zhang WJ Chorney MJ Koltun WA 《The Journal of surgical research》2000,92(2):214-221
The CD1d molecule has been implicated to play a role in inflammatory bowel diseases (IBD), possibly through its presentation of an intestinal antigen trigger. To understand the role of the CD1d class I-like protein in IBD, we investigated the molecule's expression in diseased intestinal tissue and determined its potential to undergo specific recognition by intraepithelial and peripheral blood lymphocytes (PBLs) derived from IBD patients. We have observed an increase in precipitable CD1d in inflamed tissues, which suggests CD1d up-regulation in IBD; this was not accompanied by the occurrence of CD1d-specific cytotoxicity by lymphocytes isolated from the same tissue sites. In contrast, we have observed CD1d-specific cytotoxicity by PBLs from both patients and normal controls mediated by a possibly unique type of lymphocytic cell. These observations support a model in which intestinal inflammation may be initiated by circulating PBLs following the tissue-specific upregulation of CD1d. These activated PBLs may then be the source of the extraintestinal manifestations observed with IBD. We therefore propose that the cells responsible for this activity may play a role in regulating immune responses through the specific recognition of CD1d-specific antigen(s). 相似文献
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Jiang WZ Jin NY Li ZJ Zhang LS Wang HW Zhang YJ Han WY 《第二军医大学学报》2006,27(4):434-434
To express the core protein of HIV-1 of Chinese prevalent strain (HIV-1 (CN)) in Pichia pastoris, the fulllength gag gene was inserted into the secretory expression vector pHILS1. Linearized recombinant plasmid pHILGAG by Sail was electrotransformed into the yeast strain GS115, and the yeast transformants were identified by PCR. To induce the interest protein to be expressed, the PCR positive transformants were inoculated in the medium of BMGY and BMMY, mRNA of the strain was detected by RT-PCR, and the expressed protein was analyzed by SDS-PAGE, Western blotting and thin layer scanning. mRNA (1.3 kb) was amplified by RT-PCR. SDS-PAGE and Western blotting analysis showed that the molecular mass of the expressed protein was 55 kD, which was similar to the expected value, and the expressed protein could react with McAb to HIV-1 p24. Thin layer scanning analysis demonstrated that the whole amount of the expressed protein was approximately 13 % of the soluble protein in the supernatant. The recombinant yeast had good genetic stability. The optimal expression conditions of the engineering yeast were as follows: BMMY medium, 80-90% of dissolved oxygen, 1% methanol, and 3-day-cultivation course. Gag proteins were expressed under the optimal expression condition and purified via gel filtration chromatography. The purity of the interest protein was up to 85 %. After the purified proteins were inoculated into BALB/c mice, the anti-HIV-1 antibodies in the immunized mice could be detected by Western blotting. 相似文献
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Surgical Management of Ulcerative Colitis in the Presence of Primary Sclerosing Cholangitis 总被引:3,自引:2,他引:3
INTRODUCTION: The surgical management of ulcerative colitis in the patient with primary sclerosing cholangitis is controversial. METHODS: This study was designed as a retrospective chart review of all patients with primary sclerosing cholangitis who were surgically treated for ulcerative colitis. RESULTS: Sixteen patients with primary sclerosing cholangitis and ulcerative colitis were identified. The indication for ulcerative colitis surgery was dysplasia in 7 patients (44 percent), cancer in 2 (13 percent), intractability in 4 (25 percent), and unknown in 1. Final colon pathology demonstrated cancer in three patients and dysplasia in four. Two patients had biliary cancer discovered at the time of orthotopic liver transplantation. Thirteen patients were known to have primary sclerosing cholangitis when they underwent surgery for ulcerative colitis; two patients with severe primary sclerosing cholangitis underwent simultaneous orthotopic liver transplantation/total abdominal colectomy and did well with subsequent ileal pouch reconstruction. Two patients had orthotopic liver transplantation first and then ileal pouch-anal anastomosis (1 patient) or total abdominal colectomy (1 patient) and did well. Seven patients had well-controlled primary sclerosing cholangitis on medication and underwent ileal pouch-anal anastomosis or total abdominal proctocolectomy without significant hepatic compromise. One patient with moderate primary sclerosing cholangitis underwent ileorectal anastomosis and had severe liver failure postoperatively but survived. Another patient with worsening primary sclerosing cholangitis after total abdominal colectomy has since developed persistent bleeding from peristomal varices. CONCLUSIONS: The overall cancer/premalignant lesion rate was high (50 percent in this study) in patients with primary sclerosing cholangitis and ulcerative colitis. Complications associated with the surgical management of ulcerative colitis are largely dictated by the degree of liver disease present at the time of surgery. Patients with significant primary sclerosing cholangitis that requires colectomy can undergo simultaneous orthotopic liver transplantation/total abdominal colectomy and then be candidates for subsequent ileal pouch-anal anastomosis reconstruction once liver function has improved. Patients with well-controlled primary sclerosing cholangitis can undergo ileal pouch-anal anastomosis surgery safely. 相似文献
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Zhenwu Lin John P. Hegarty Wei Yu Jon A. Cappel Xi Chen Pieter W. Faber Yunhua Wang Lisa S. Poritz Jian-Bing Fan Walter A. Koltun 《Digestive diseases and sciences》2012,57(12):3145-3153