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1.
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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A Western blot to detect anti-HSP70 autoantibodies has been reported to be of diagnostic value for immune-mediated hearing loss patients. While setting up this Western blot in our lab, we detected two main problems. First, some patients were positive for antibodies to a 70-kDa protein when tested against a whole cell lysate, but negative if the antigen used was purified HSP70. Second, if high amounts of purified HSP70 were loaded on the gel, both patients and healthy controls were positive. We have developed and optimized an ELISA as an alternative to the Western blot. This assay is more appropriate to identify positive and negative individuals because it is semi-quantitative. The ELISA is also more sensitive, requiring very low concentrations of the antigen and thus minimizing false positives. Finally, we demonstrated that immune-mediated hearing loss patients recognize mainly the native form of HSP70, a fact that potentially leads to false negatives when a denaturing Western blot assay is used for diagnosis. To test the diagnostic value of the ELISA, we performed a blind test with 70 hearing loss patients, as well as 30 healthy controls. A sensitivity of 84% and a specificity of 93% were obtained, superior to what has been reported so far for the Western blot.  相似文献   
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The authors report the results of 17 intracystic injection of colloidal 186 rhenium, 2 colloidal 198 gold, and 1 colloidal 90 yttrium for endocavitary treatment of 18 cystic craniopharyngiomas (16 pts during a period ranging from January 1975 till July 1982. Follow-up studies ranging from 12 to 72 months (m: 36 m) revealed that all craniopharyngiomas cysts were effectively treated with cessation of fluid formation, progressive shrinkage of the formerly expansive cysts, and finally cyst obliteration in 75% of the cases. No early or late side-effects were observed during the entire observation period. Late reexpansion of one craniopharyngioma cyst, observed at 11 months, was successfully treated by a second injection. Leakage of colloid isotope into the CSF spaces during the "test" or "therapeutic" injections occurred in 18% of the global number of injections, however no clinical complications were observed. On the basis of a clinical dosimetric study a 30 000 rads wall-dose, not exceeding 40 000 rads is actually considered as the safer dose for endocavitary treatment of craniopharyngioma.  相似文献   
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Objective To investigate the clinical and pathological characteristics of pauci-immune crescent glomerulo~nephritis (PICGN) in Chinese patients. Methods During 13 years (1985-1998), 6400 patients underwent non-transplanting renal biopsy. Twenty-four patients were diagnosed as PICGN. All clinical and laboratory data of these patients were collected from the patients’ records and used for detailed analysis. The diagnosis is based on clinico-pathologic findings. Results Of the 24 patients, 16 were females and 8 were males, with median age of 33 years (ranged 10-76 years). Microscopic polyarteritis (MPA) (33.3%) and systemic vasculitis (8.3%) were the secondary diseases. The incidence of PICGN was 0.38% in renal biopsies and 22.9% in crescentic glomerulonephritis. Clinically, most patients (75.0%) showed rapidly progressive nephritis with enlarged kidneys. At onset, gross hematuria was noted in 58.3% of patients, hypertension in 45.8%, nephrotic syndrome in 41.7%, and oliguria in 25.0%. However, systemic symptoms were rare except for anemia. Pathologically, necrosis of glomerular capillaries (62.5%), infiltration of monocytes and neutrophil cells in glomeruli (66.7%), and vasculitis in the interstitium (53.3%) were observed. In addition, glomerulosclerosis was noted in 45.8%, severe tubular atrophy in 83.3% and interstitial fibrosis in 75.0%. Anti-neutrophil cytoplasmic antibodies (ANCAs) were positive in 52.2%. All patients except two received intensively immunosuppressive therapy. Sixteen patients were available for long-term follow up (median 29.8 months, range 8-92 months). Twelve of them had life-sustaining renal function, four had normal serum creatinine (<124?μmol/L) and only 4 patients were dialysis-dependent. Conclusion PICGN is not rare in China. Early diagnosis and administration of immunosuppressive therapy, particularly in patients with rapidly progressive glomerulonephritis (RPGN), are important for good prognosis.  相似文献   
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Dosage and schedules for the treatment of malignant glial tumors using IFN (interferon) are still uncertain and controversial. In this study we give the preliminary results of treatment in 28 patients with glioblastoma multiforme (GBM). 6 patients were treated with local injection of β-IFN through an Ommaya reservoir; 4 patients with β-IFN followed by systemic chemotherapy (Cisplatin+Etoposide), and 18 patients with chemotherapy only. Two end points were evaluated: 1) Whether or not the patients responded to treatment. 2) Length of Time to Tumor Progression(TTP) after surgery. We found that IFN alone was ineffective. Results were improved when local immunotherapy was associated with systemic chemotherapy. New drugs and investigation of possible pharmacological synergism are needed.  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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