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41.
Rutkowski R Moniuszko T Stasiak-Barmuta A Kosztyła-Hojna B Alifier M Rutkowski K Tatarczuk-Krawiel A 《Archivum immunologiae et therapiae experimentalis》2003,51(6):421-428
CD80 and CD86 seem to play an important role in the allergen-induced secretion of interleukin (IL)-5 and IL-13. Up to now, the expressions of CD80 (B7.1) and CD86 (B7.2) on monocytes and the kinetics of the expression of these molecules on lipopolysaccharide-stimulated monocytes in nonatopic asthma have not been defined. Using monoclonal antibodies, we have compared the expressions of CD80 (B7.1) and CD86 (B7.2) on the monocytes of healthy persons and nonatopic asthmatic patients. We have also assessed the effect of CD80 and CD86 inactivation on IL-4 and interferon (IFN)-gamma production in nonatopic asthmatics and healthy subjects. We found that a low expression of CD80 (1.64 +/- 0.65 vs. 3.53 +/- 1.43%) and a moderate expression of CD86 (41.25 +/- 13.4 vs. 49.46 +/- 11.49%) on the studied monocytes were characteristic for asthma. In nonatopic asthma patients inactivation of CD80 or CD86 blockade significantly reduced IFN-gamma production by T lymphocytes (p < 0.02; p < 0.03). In both the studied groups, anti-CD80 antibodies did not diminish T lymphocyte production of IL-4. However, anti-CD86 antibodies significantly (p < 0.04) reduced the IL-4 concentration in culture supernatants. Our results confirm that both the CD80 and CD86 molecules play an important role in the maintenance and amplification of the inflammatory process. It suggests that in the inflammatory process that occurs in nonatopic bronchial asthma, Th1 as well as Th2 lymphocytes are equally important. 相似文献
42.
Between 1984 and 2000 in the Thoracic Surgery Centre pneumonectomies were performed in 947 patients. Postpneumonectomy empyema (PE) occurred in 67 (7%) patients. The aim of this paper were: analysis the reasons of postpneumonectomy empyema appearance, defined bacterial flora, clinical course and optimal management. The causes of PE were: pleural cavity haematoma (20 patients-29.8%), wound suppuration (18 patients-26.8%), bronchial fistula (31 patients-46.2%). These complications appeared singly or together in 49 (73.1%) patients. In 2 (3.0%) patients a long treatment in the Intensive Care Unit because of postoperative shock was the cause of infection. In 3 (4.5%) cases the cause of empyema was associated with infection during the operation. In 13(19.4%) cases the cause of empyema was not established. In 55 patients infections of pleural cavities were diagnosed in the first 8 weeks after operations. In 12 patients empyemas were established later. 12 (17.9%) patients died during the analyzed 1 year period after operation. In 18 (26.9%) patients infections were caused by only one bacterial strain and in 49 (73.1%) by two or three bacterial strains. The different methods of treatment (thoracentesis, drainage, operation) depending on general condition of patient were done. 相似文献
43.
Schüpbach J Böni J Bisset LR Tomasik Z Fischer M Günthard HF Ledergerber B Opravil M;Swiss HIV Cohort Study 《Journal of acquired immune deficiency syndromes (1999)》2003,33(3):292-299
An HIV-1 p24 antigen test involving signal amplification-boosted ELISA of heat-denatured plasma was evaluated prospectively in 55 patients whose viral RNA in plasma had previously been suppressed for at least 6 months under antiretroviral combination therapy. During a median follow-up of 504 days, CD4 counts increased by a median of 62 cells per year. By univariate and multivariate linear regression analysis, the level of p24 antigen as expressed by the absorbance/cutoff ratio was a significant inverse correlate of both the CD4 count in a sample (p =.013) and its annual change in a patient (p <.0001). The p24 antigen retained significance even among 48 individuals whose HIV-1 RNA, apart from occasional blips, remained below 400 copies/mL. Batch-wise retesting of 70 samples from 5 such patients with a further improved procedure showed measurable p24 antigen in all but 1 sample and an inverse correlation with both the CD4 count (p =.0331) and percentage (p <.0001), thus confirming the prospectively generated data. Comparison of p24 antigen and HIV-1 RNA concentrations indicate that the p24 antigen detected in these samples is not associated with viral RNA-containing particles and may originate from other compartments of virus expression. 相似文献
44.
45.
Katarzyna Mizia-Stec Zbigniew Gsior Romuald Wojnicz Maciej Haberka Marcin Mielczarek Andrzej Wierzbicki Katarzyna Pstra Marek Hartleb 《Cardiovascular pathology》2008,17(4):250-253
Dilated cardiomyopathy (DCM) is one of the most common causes of heart failure with a prevalence of 1:2500. There are several primary and secondary etiologic factors, including gene mutations, infection agents, particularly viruses, toxins, autoimmune, and systemic disorders, and pheochromocytoma, neuromuscular, metabolic, mitochondrial, and nutritional disorders. However, a precise diagnosis can be reached only in no more than 50% of all cases. Herein, we report a rare case of hepatic damage and severe DCM as a consequence of relatively popular socially used narcotic-Ecstasy (3,4-methylenedioxy-N-methylamphetamine [MDMA]). 相似文献
46.
47.
In the reaction of triisobutylene with AlBr3/DBr system, backbone isomerization and formation of higher oligomers takes place, in addition to deuteration. Both reactions are explained by the cleavage of the backbone bonds of the intermediate carbonium ions. The fragments formed can react with other components of the reaction system. The possible role of these reactions in the mechanism of termination and chain transfer in the cationic polymerization of isobutylene is discussed briefly. 相似文献
48.
Induced genomic instability in the human B lymphoblastoid cell line TK6 manifests itself as increases in end-to-end chromosome fusions and non-reciprocal chromosome translocations. It is not associated with elevated frequencies of specific locus mutations or other cytogenetic alterations. Previous studies on a limited number of cells and end-points suggested that induced instability in TK6 mirrors spontaneous instability in terms of the types of alterations observed. In the present study we expanded on our previous analysis to include more cells and more end-points in order to derive a more precise measure of spontaneous instability in TK6 cells. The frequency of normal growth rate thymidine kinase mutants (TK(-/-)), measured in 44 independently isolated clones, was 2.73 +/- 0.78 x 10(-6)/cell, while that for slow growth mutants was 2.39 +/- 0.52 x 10(-6)/cell. These are similar to the frequencies observed for HPRT mutants in primary human cells. There was wide variation in chromatid break frequencies, but the average break frequency, at 0.04+/-0.01 breaks/cell, was only slightly higher than that reported for primary human cells. In contrast, the dicentric frequency of 0.006/cell was more than 10-fold higher for TK6 cells than that reported for normal primary human cells. Furthermore, the dicentrics in TK6 cells are unusual in that they are the result of end-to-end chromosome fusions. TK6 cells also show much higher levels of non-reciprocal chromosome translocations than are usually observed in primary human cells. The results suggest an inherent instability in TK6 cells that differs from what is observed in primary cells in that it affects the frequency of end-to-end chromosome fusions and non-reciprocal chromosome translocations, but not TK gene mutations or other cytogenetic alterations. 相似文献
49.
M. Deckert-Schlüter Josef Marek Michael Šetlík Jana Marková E. Pakos Robert Fischer Otmar D. Wiestler 《Virchows Archiv : an international journal of pathology》1998,432(5):477-481
A 62-year-old woman presented with loss of memory and a mild hemiparesis. Neuroradiology demonstrated a left frontoparietal
tumour. Biopsy specimens of this lesion revealed intracerebral Hodgkin’s lymphoma, a diagnosis supported by immunohistochemical
reactions of the tumour cells for the CD30 antigen. Additional cell cycle studies revealed a high proliferative activity of
the tumour cells in association with absence of apoptosis. There was no evidence that overexpression of bcl-2 or Epstein-Barr
virus infection was involved in the pathogenesis of this neoplasm. Lymphomas in the lung were detected 3 months later. Following
neurosurgical excision, radiotherapy, and chemotherapy, the patient had no evidence of Hodgkin’s disease after 13 months of
follow-up.
Received: 8 October 1997 / Accepted: 8 December 1997 相似文献
50.
Miroslav Marek Michael Roman Danica Dosko
ilov Svatopluk Pokorný 《Macromolecular chemistry and physics.》1986,187(10):2337-2344
The polymerization of 3-chloro-2-methyl-1-propene was investigated at temperatures between 0 and ?80°C, using AlCl3 and AlBr3 as initiators. The molecular weights of the resulting oily products depend on the polymerization temperature and varied in the range of the number-average molecular weight M?n = 400–620. The course of polymerization was studied and the characteristic groupings in the oligomeris were identified by means of 1H NMR and 13C NMR spectroscopy. Based on the results the mechanism of partial reactions was discussed to explain the new type of propagation in the cationic polymerization. 相似文献