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991.
OBJECTIVES: Beh?et's disease (BD) is a chronic inflammatory disorder of still unknown etiology, characterized by endothelial cell injury/dysfunction and thrombosis and/or aneurysm of large blood vessels. Thrombophilia may play a role in the pathogenesis of thrombosis in BD. The common inherited gene defects, factor V (FV) 1691A (Leiden) and prothrombin (PT) 20210A, are known risk factors for thrombosis. The FV 4070G polymorphism was shown to influence circulating FV levels and to contribute to the activated protein C resistance phenotype. The aim of the study was to evaluate the role of FV 1691A, FV 4070G and PT 20210A gene mutations in Turkish BD patients with and without venous thrombosis. METHODS: Seventy-one patients with BD (27 with venous thrombosis) and 91 healthy subjects were included in the study. FV 1691A, FV 4070G, and PT 20210A mutations were determined by a method based on PCR-RFLP. RESULTS: The frequency of FV 1691A heterozygous mutation in BD patients with venous thrombosis (25.9%) was significantly higher than that in healthy subjects (8.8%; OR = 3.63; 95% CI 1.18-11.2). Although the frequency of this mutation in patients with venous thrombosis was higher than that in the patients without venous thrombosis (11.4%), the difference did not reach a statistically significant level (OR = 2.73; 95% CI 0.77-9.70). In BD patients with thrombosis, the frequencies of FV 4070G and PT 20210A were not significantly different compared to the BD patients without venous thrombosis and healthy subjects. CONCLUSIONS: Our results suggest that the FV 1691A, FV 4070G, and PT 20210A mutations are unlikely to play an important role in the pathogenesis of thrombosis in patients with BD.  相似文献   
992.
We studied the ability of the vigilance-promoting drug modafinil to modulate the anterograde and retrograde changes in tyrosine hydroxylase (TH) immunoreactivity and in dopamine (DA) stores in the nigro-neostriatal DA neurons, following a partial hemitransection of this ascending DA system, using a combined morphometrical, biochemical and behavioural analysis. Modafinil was given daily i.p. in doses of 10–100 mg/kg, starting 15 min after the lesion, and the partially hemitransected rats were killed 2 weeks later. Changes in TH-immunoreactive nerve cell bodies and nerve terminals induced by the partial hemitransection were studied in the substantia nigra and neostriatum in combination with image analysis. The substantia nigra and neostriatum were also subjected to biochemical analysis of DA, 3,4-dihydroxyphenylacetic acid and homovanillic acid levels. Modafinil treatment dose-dependently (10–100 mg/kg) counteracted the hemitransection-induced disappearance of nigral TH-immunoreactive nerve cell body profiles and neostriatal TH-immunoreactive nerve terminal profiles. A 2-week treatment with 100 mg/kg of modafinil also counteracted the hemitransection-induced depletion of DA stores in the neostriatum and the ventral midbrain. Moreover, the repeated daily treatment with modafinil (100 mg/kg) protected against the hemitransection-induced disappearance of striatal 5-hydroxytryptamine, 5-hydroxyindoleacetic acid and noradrenaline levels. Striatal DA function was analysed by studying apomorphine-induced (1 mg/kg, s.c.) ipsilateral rotational behaviour 4 and 11 days after the operation. A marked dose-dependent reduction of ipsilateral rotational behaviour was demonstrated after the daily modafinil treatment in the partially hemitransected rats. In another model involving unilateral nigral microinjections of 6-hydroxydopamine, acute (one single dose) modafinil (100 mg/kg) did not affect the contralateral rotational behaviour induced by apomorphine (0.05 mg/kg s.c.), when given 30 min before the apomorphine. Taken together, morphological, neurochemical and behavioural evidence has been obtained that anterograde and retrograde changes induced in the DA stores and TH immunoreactivity of the nigro-neostriatal DA neurons by a partial hemitransection are counteracted by modafinil in a dose dependent way with 100 mg/kg producing a significant protective action against impairment of DA transmission. The results of this study open up the possibility that modafinil may protect against the anterograde and retrograde degeneration of nigrostriatal DA neurons seen after mechanically induced injury.  相似文献   
993.
The case of a 20-year-old woman with systemic mastocytosis is reported. The disorder was not preceded by a clinically diagnosed local form of the disease; fibrous changes in organs, bone changes, eosinophilia and increased serotonin, heparin or histamine levels had not been observed. Clinical symptomatology was typical and the patient died one year after the first signs of the disease.  相似文献   
994.
Linear poly(iminoethylene) was synthetised by cationic polymerization of 2-methyl-2-oxazoline using BF3? O(C2H5)2, SnCl4, and CH3COBF4 as initiators and in the presence or absence of CH3CN. The resulting product, poly(N-acetyliminoethylene), was then hydrolysed in basic medium. The resulting poly(iminoethylene) was identified and characterized by 1H NMR, 13C NMR, X-ray diffraction, and differential scanning calorimetry (DSC). The synthetised polymer will be used as a polymeric support in ionic-exchange resins as well as in macromolecular pesticides.  相似文献   
995.
In the process of developing a decision support system based on flow cytometric data for the diagnosis of immunodeficiency, assessment of lymphocyte subpopulations in human peripheral blood provides the key for further analysis. Samples from 273 'healthy' Hungarian subjects were measured between 1998 and 1999. Immunophenotypic data are compared here (unadjusted for gender) by different age groups: I 0-6 years (n=45); II 7-18 years (n=71); III 19-35 years (n=72); IV 36-55 years (n=48); and V 56-99 years (n=37). Two-color flow cytometric analysis was performed using the Becton Dickinson Simultest IMK Plus kit (CD45/CD14, isotype control, CD3/CD19, CD4/CD8, CD3/HLA-DR, CD3/CD16+56). All lymphocyte subpopulations were measured in all blood samples identically. The quality criteria involved at least 95% of total lymphocytes in the analysis gate, homogenous CD45+ lymphocyte population (minimum of 2000 events in the gate, CD45+ >95%). The frequency of B lymphocytes was the highest, significantly, in the youngest Hungarian subjects, but there were no significant changes with age comparing the data of other II-V age groups. On the other hand, some T subpopulations changed with aging; both CD4 and CD8 subsets varied over time including the elevation of the fraction of activated T cells as well as LGL-NK cells. Some of these changes were significant by statistical tests. Interpretation of flow cytometric data is time-consuming and requires human knowledge of an expert laboratory staff. To facilitate the diagnosis of immunodeficiency, a pilot study aiming at the development of a diagnostic algorithm has been initiated. Algorithm nodes compare the frequency of each lymphocyte subpopulations to the generated reference values. This knowledge-based system describes a short summary report as a result of the comparison, and points to some values requiring further human examination to reach a final conclusion. These reference values and the expert system appear to be a recommended basis for comparing and combining results from different laboratories.  相似文献   
996.
Several endocrine cell types were ultrastructurally characterized during the differentiation of the intestine and rectum of sea bass (Dicentrarchus labrax L.) larvae. Only one cell type (type I) was found in the posterior region of the undifferentiated gut of 5-day-old larvae (phase I). Types V and VI were found in both the intestine and rectum, types II, III and IV in the intestine, and types VII and VIII in the rectum of 9- and 12-day-old larvae (phase II), the rectum alone showing signs of functional differentiation. In phase III larvae, in which both the intestine and rectum were differentiated, types IX, X, XI, XII, XIII, XIV and XV were found in the intestine, only types X, XI and XII being seen in the rectum. Besides these, a new cell type, XVI, was observed in the intestine of 55- and 60-day-old larvae (phase IV), in which the digestive tract was completely differentiated. The endocrine cells appearing in phases I and II showed very scarce secretory granules and the ultrastructural features of undifferentiated cells. Some endocrine cell types in the earliest developmental stages were related to some of those found later. A maturational process of the endocrine cell types paralleled the differentiation of the intestine and rectum, with an apparent increase in the number of secretory granules accompanying organelle development.  相似文献   
997.
This study investigated the relationship between theory of mind (ToM) deficits and visual perception in patients with schizophrenia (N=52; 17 remitted and unmedicated) compared with healthy controls (N=30). ToM was assessed with the Eyes Test, which asked participants to choose which of 4 words best described the mental state of a person whose eyes were depicted in a photograph. Visual perception was evaluated with form and motion coherence threshold measurements. Results revealed that patients with schizophrenia (both remitted and nonremitted) showed deficits on the Eyes Test and the motion coherence task. ToM dysfunctions were associated with higher motion coherence thresholds and more severe negative symptoms. This suggests that ToM deficits are related to motion perception dysfunctions, which indicates a possible role of motion-sensitive areas in the pathophysiology of schizophrenia.  相似文献   
998.
Among 363 strains of Staphylococcus aureus, 21 were shown to produce bacteriocins (Bac), antimicrobial peptides with potential biotechnological applications. This collection includes strains which are either isolated from food, patients and healthy cattle, or are involved in subclinical bovine mastitis. From these 21 strains, 17 were shown to carry closely-related 8.0-kb Bac plasmids encoding bacteriocins either identical to or similar to aureocin A70, a bacteriocin able to inhibit strains of Listeria monocytogenes, a food-borne pathogen. Such findings prompted us to investigate the genetic relationships among these Bac+ strains. To obtain more discriminatory results, a combined analysis of AP-PCR, rep-PCR, and a modified PCR technique that we designated SD-PCR was employed. The 17 Bac+ strains harboring 8.0-kb Bac plasmids exhibited seven fingerprint patterns. One such genotype was composed of 8 out of the 11 strains associated with bovine mastitis, which suggests the prevalence of a clone of Bac+ strains involved in this animal infection carrying 8.0-kb Bac plasmids. Our data support the assumption that Bac+ strains of S. aureus carrying genetically related 8.0-kb Bac plasmids do not belong to a single clone. It seems, therefore, that 8.0-kb Bac plasmids have spread horizontally among different S. aureus strains. There also seems to be genetic diversity among the remaining Bac+ strains analyzed.  相似文献   
999.
The aims of this study were to evaluate the mutagenic and cytotoxic activity of mercurous chloride by the micronucleus technique in vivo on the bone marrow of golden Syrian hamsters after a single i.p. drug administration. Forty male golden Syrian hamsters were classified into eight groups: negative control, positive control and six groups treated with different doses of mercurous chloride (1.25, 2.5, 5, 10, 20 and 40 mg/kg). The negative control was injected with physiological saline i.p. and the positive control with cyclophosphamide at a dose of 80 mg/kg i.p. With respect to mutagenic effect, the average number of micronucleated polychromatic erythrocytes (MPE) in hamsters treated with different doses of mercurous chloride was not significant compared with the negative control. With respect to cytotoxic effect, the average polychromatic erythrocyte/red blood cell ratio showed a significant decrease when the doses were higher than the 2.5 mg/kg dose compared with the negative control. In conclusion, this preliminary study shows a cytotoxic effect but not a mutagenic effect of calomel in vivo at one time point (24 h).  相似文献   
1000.
Selected immunological, biochemical, and other viral hepatitis B (VH-B) markers were followed and analysed during "conventional" or human interferon alpha (HuIFN alpha) therapy of patients with different forms of VH-B. The immunological data obtained from "conventionally"-treated acute hepatitis B (AH-B), prolonged acute hepatitis B (AH-BP) or chronic active hepatitis B (CAH-B) patients disclosed differences unsatisfactory for comparison of the influence of HuIFN alpha therapy on changes of the immunological markers. More valuable data were obtained through continuous registration of the dynamics of selected blood markers. Partial effects on immunological parameters were seen after HuIFN alpha administration to 2 patients with developing CAH-B infection. Progression of the disease was markedly halted in these both patients after IFN treatment.  相似文献   
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