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Objective:To study the effect of oral administration of dimethyl dimethoxy biphenyl dicarboxylate(DDB) on adjusting angiogeneic/inflammatory mediators and ameliorating the pathology of bones in rats with collagen-induced arthritis(CIA).Methods:Wistar rat model of CIA was set up using bovine collagen type Ⅱ.Fifty rats were divided into five groups randomly:normal,CIA model,DDB treatment,methotrexate(MTX) treatment,and combined DDB+MTX treatment.Ankle joints of rats were imaged with digital X-ray machine to show the destruction of joints.Fore and hind paw and knee joints were removed above the ankle joint then processed for haematoxylin and eosin staining.Plasma levels of vascular endothelial growth factor(VEGF),platelet derived growth factor,interleukin-8(IL-8),IL-4,tumor necrosis factor α(TNF-α),and cyclooxygenase-2(COX-2) were quantified by enzyme-linked immunosorbent assay.Nitric oxide levels were detected by Griess reagent.Results:Compared with the CIA model group,a remarkable reduction in various angiogenic(VEGF and IL-8) and inflammatory mediators(TNF-α,IL-4 and COX-2) after treatment with DDB either alone or combined with MTX(P0.05 or P0.01).Histopathological and X-ray findings were confirmatory to the observed DDB anti-arthritic effect.The DDB-treated group showed amelioration in signs of arthritis which appeared essentially similar to normal.Conclusion:Our data shed light on the therapeutic efficacy of DDB in experimental rheumatoid arthritis(RA) compared with a choice drug(MTX) and it may be offered as a second-line drug in the treatment of RA.  相似文献   
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Microspheres of 5-fluorouracil have been prepared, using three grades of ethyl cellulose as wall forming materials, and utilizing a solvent evaporation technique under ambient conditions. An alcoholic solution of 5-fluorouracil and polymer was dispersed in liquid paraffin containing 33.3 per cent n-heptane. The effect of stirring rate, time of stirring, drug loading, and polymer grade on drug release in two different media were evaluated. The drug loaded particles were spherical in shape and had a diameter range of 25-200 mm and were suitable for incorporating into a gel base. Drug release studies in aqueous media, showed that acidic media provide a faster release rate than neutral media. The drug release study from an aqueous gel base preparation at pH 7.0 through a synthetic membrane was found to be promising for formulation of a gel-microsphere product for the treatment of skin lesions.  相似文献   
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Pseudo-angiomatous hyperplasia of mammary stroma (PASH) is a histopathological entity which is a microscopic fortuitous finding in mammary biopsies performed for different reasons. It may be symptomatic and appears then as a palpable lump. The term pseudo-angiomatous emphasizes the characteristic aspect of the stroma simulating a vascular tumor. We report a case of PASH in a 71 year-old woman who presented a recurring breast mass with rapid swelling of the mammary gland (70 x 60 x 20 cm) treated by mastectomy. PASH must be distinguished from a well-differentiated angiosarcoma. It is ruled out by immunohistochemistry.  相似文献   
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Of 1,500 cervical tissue specimens, 27 cases showed histologic changes of reactive glandular atypia which we defined as endocervical cells with large hyperchromatic, often irregular nuclei, which did not fulfill the criteria for endocervical adenocarcinoma. Eighteen of these 27 cases had preceding or concurrent cervico-vaginal smears. Six of these showed cells which were similar to those seen in histologic sections. The cytologic characteristics of these cells are defined. To determine if atypia is related to inflammatory-regenerative changes, 29 cases of endocervical polyps were examined, of which 11 showed histologic changes of endocervical reactive atypia; 4 showed these changes cytologically as well. Twenty-eight cases of routine hysterectomy specimens were examined, of which 2 cases showed endocervical reactive atypia, which indicated that the atypical changes were indeed reactive. Nine out of 27 cases were associated with hormonal usage. Fourteen cases were associated with squamous intraepithelial lesions or evidence of human papilloma virus. Follow-up of our 27 index cases revealed no progression to adenocarcinoma. These findings indicate that atypia, as we define it, of the endocervix can be due to inflammatory-reparative changes or possibly related to hormonal usage, and permit its separation from precursor lesions of endocervical adenocarcinoma.  相似文献   
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The effect of inclusion complexation of furosemide in cyclodextrins (CyD) on the bioavailability of the drug was studied on normal human volunteers. The excretion rate of the drug was determined by HPLC for a period of 24 h. post dosing. Several pharmacokinetic parameters were calculated and statistically analyzed. viz., peak excretion rate, peak excretion time, half peak time, elimination rate constant, area under the excretion rate time-curve as well as the total amount of drug excreted. The obtained results show that on administration of furosemide in the form of an inclusion complex in CyDs particularly beta-CyD or its dimethyl derivative may improve its biological performance, taking into consideration that furosemide is characterized by a rapid onset and a short duration of action. Inclusion complexation of furosemide in CyDs leads to a more or less delay in its onset of action, a significant increase in its duration of action as well as significant augmentation in its overall biological availability.  相似文献   
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Analysis of the p21 gene in gliomas   总被引:4,自引:0,他引:4  
The p21 gene encodes a cyclin dependent kinase inhibitor protein (p21) which has a tumor suppressive activity in a variety of tumor cell lines. Since, the p21 gene is up-regulated by the p53 tumor suppressor gene, which is frequently mutated in gliomas, acting therefore in the same control pathway, it constitutes a good candidate gene to be also inactivated in these tumors. To test this hypothesis, DNAs from 81 gliomas (48 glioblastomas, 11 anaplastic astrocytomas, 10 low-grade astrocytomas, 12 oligodendrogliomas and mixed gliomas), were investigated for mutations in the p21 coding sequence by denaturant gradient gel electrophoresis followed by sequencing. All these tumors have been previously screened for p53 mutations. Three different DNA variants were identified on codon 31 (17 cases), 27 (1 case) and 117 (1 case) and shown to be also present in matching constitutional DNA, suggesting they were polymorphisms. None of the tumors demonstrated a somatic mutation. No significant correlation between the presence of a p21 variant and the p53 mutation tumor status was observed. In conclusion, mutation in the p21 gene unlikely contributes to the development of gliomas.  相似文献   
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