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141.
142.
The experimental infection of immunocompetent and immunodeficient athymic mice with an avirulent encephalitogenic Toxoplasma strain (DX strain) was employed to study the ensuing encephalitic process by use of histological and immunocytochemical methods. In the acute phase of the infection Toxoplasma cysts and tachyzoites were accompanied by an infiltrate composed of macrophages, CD4+ and CD8+ T cells. In the chronic stage a granulomatous encephalitis developed. In contrast to immunocompetent NMRI mice, athymic nude NMRI mice died 3 weeks post-infection because of a generalized toxoplasmosis with predominant involvement of the brain. A salient feature of murine Toxoplasma encephalitis was up-regulation of class I and II major histocompatibility complex (MHC) gene products. Class I antigen was widely expressed on microglial cells and astrocytes. Class II antigen was only expressed on microglial cells despite a considerable astrogliosis. Our results indicate a differential expression of MHC-determined antigens on brain cells in acute and chronic murine Toxoplasma encephalitis. 相似文献
143.
Total gastrectomy is discussed as the operation of choice among different surgical approaches for gastric carcinoma. We prefer the performance of an elective total gastrectomy with systematic lymphadenectomy (compartments I and II) and obligatory splenectomy. A retrospective study of 1,704 consecutive cases of gastric carcinomas showed a better outcome following total gastrectomy in relationship to distal subtotal gastrectomy, but these results cannot be used as evidence because of the lack of a prospective study. Nevertheless, a precise analysis of our cases in regard to tumor site and tumor type could show a frequency of only 6% to maximally 30%, in which elective total gastrectomy may represent a procedure too extensive to justify for an oncological course. 相似文献
144.
H Ku?nierczyk J Matuszyk C Radzikowski 《Archivum immunologiae et therapiae experimentalis》1989,37(5-6):547-556
The alkylating agent ifosfamide synthesized according to own method at the Institute of Pharmaceutical Industry, Warsaw, was compared in biological evaluations with Holoxan (Asta-Werke's ifosfamide). No significant differences between tested compounds were found in respect of acute toxicity and antitumor activity in experimental systems in mice. 相似文献
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148.
Recurrence, progression and survival in bladder cancer. A retrospective analysis of 232 patients with greater than or equal to 5-year follow-up 总被引:1,自引:0,他引:1
A retrospective study of 232 bladder tumours with minimum follow-up 5 years is presented. The carcinoma was superficial in 66%, muscle-invasive in 31% and could not be staged in 3%. Primary treatment was mainly transurethral resection for superficial tumour, but was cystectomy or radiotherapy in 22 of 29 T1 G3. Of the superficial tumours, 71% recurred. Progression to higher T stage occurred in 15% of Ta and 29% of T1 tumours, and half of these patients died of bladder cancer. The corrected 5-year survival rates in grades 1, 2A, 2B and 3-4 were 96, 84, 64 and 43%, and in stages Ta, T1, T2 and T3 they were 94, 69, 40 and 31%. All patients with T4 tumour died within 4 years. Among the 45 patients with 40 Gy irradiation + cystectomy, the corrected 5-year survival rate was 83% in superficial and 64% in muscle-invasive tumours, and among the 38 with radical radiotherapy the rates in T1-3 were 46, 36 and 13%. Transurethral resection was successful in most Ta cases. Most T1 tumours were, like T2-4, of higher grade than Ta. Prognosis was worse in T1 than in Ta. After progression to muscle-invasive disease, even during close follow-up the outlook was poor, as poor as for patients with primary muscle-invasive disease. 相似文献
149.
(E)-5-(2-Bromovinyl)-2'-deoxyuridine (1; BrVUdR) inhibits the replication of herpes simplex virus type 1 (HSV-1) and of varicella-zoster virus (VZV) in vitro at concentrations of 0.01 to 0.23 mumol/l, whereas herpes simplex virus type 2 (HSV-2) is influenced only at 5.5 to 27 mumol/l. In comparison to some classical and newly developed antiherpetics, i. e. 5-iodo-2'-desoxyuridine (2; idoxuridine, IDU), 9-beta-D-arabinofuranosyladenine (4; vidarabine Ara-A), 9-(2-hydroxyethoxymethyl) guanine (5; acyclovir, ACV) and 2'-fluoro-5-iodo-1-beta-D-aracytosine (6;FIAC) the following order of decreasing activity was found:1 greater than 6 greater than 5 greater than 2 greater than 4 (against HSV-1) and 6 greater than 2 greater than 5 greater than 1 greater than 4 (against HSV-2). The high selectivity of the antiviral effect of BrVUdR towards HSV-1 and TZV is based on the fact, that proliferation of different mammalian cell lines is inhibited by 50% only at concentrations as high as 90 to 170 mumol/l, resulting in a therapeutical index of 1000 to 10,000. Successful treatment of an HSV-1 encephalitis in mice as well as an HSV-1 keratitis of rabbits confirmed the efficiency of 1 in experimental animal infections. No toxic side effects in both local and systemic applications were observed. Promising data from cell culture and animal experiments recommend 1 as a potential candidate for the local and systemic treatment of HSV-1 and VZV infections in man. 相似文献
150.
A significant increase of LDL-apolipoprotein B by 13% and LDL-cholesterol by 19% was observed in a group of 9 patients with hyperlipoproteinaemia Type III after bezafibrate treatment. Additional administration of colestipol caused a significant decrease of both LDL-apolipoprotein B by 18% and LDL-cholesterol by 25%. In 10 patients of hyperlipoproteinaemia Type IIb a significant decrease of both LDL-apolipoprotein B by 28% and LDL-apolipoprotein B by 18% was observed after bezafibrate therapy. When bezafibrate was given together with colestipol a further decrease of both LDL-cholesterol by 17% and LDL-apolipoprotein B by 16% occurred. HDL-cholesterol concentration increased significantly in both groups of hyperlipaemic patients during therapy. This may be the effect of both bezafibrate and colestipol. It is concluded that bile acid resins may effectively prevent the LDL-cholesterol concentration increase observed sometimes after clofibrate analogues. 相似文献