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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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中药材龟板和鳖甲中DNA的提取与扩增   总被引:22,自引:0,他引:22  
中药材龟板和鳖甲中DNA的提取与扩增王亚明,周开亚,吴平,徐珞珊(南京师范大学生物系,南京210097;中国药科大学生药学研究室,南京210009)龟鳖类药材在我国使用历史悠久,具补阴益气的功效。《中国药典》(1990年版)规定龟甲(龟板)的原动物为...  相似文献   
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N W Baylor  Y Li  Z P Ye  R R Wagner 《Virology》1988,163(2):618-621
A cDNA encoding the entire amino acid sequence of the matrix (M1) protein of influenza A/WSN/33 virus was cloned, sequenced, and expressed in a vaccinia virus system consisting of the T7 bacteriophage RNA polymerase and a plasmid carrying the M1 gene flanked by T7 polymerase promoter and terminator sequences. The transiently expressed M1 gene product comigrated on SDS-polyacrylamide gels with the endogenous WSN virus M1 protein and was recognized in Western blot analysis by three epitope-specific monoclonal antibodies directed to the M1 protein. The nucleotide sequence and the predicted amino acid sequence of the cloned WSN virus M1 coding region was found to be more than 97% homologous to that of the M1 gene of influenza virus A/PR/8/34 reported by G. Winter and S. Fields (Nucleic Acids Res. 8, 1965-1974, 1980).  相似文献   
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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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