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21.
Spatial adjacency of stimulus source and response site has been proven important for learning of simple behavioural tasks, including auditory quality and location discrimination. We investigated effect of sound source position (adjacent or not adjacent to manipulanda) on learning and performance of a complex auditory recognition memory task. Spatial adjacency of stimuli and manipulanda improved learning of a simple auditory directional task, which was an intermediate stage of training. In contrast, no improvement of learning and performance of the recognition task was found. 相似文献
22.
Remiszewski P Langfort R Podsiadło B Kuś J Płodziszewska M Radzikowska E Roszkowska B Szopiński J Tomkowski W Wawrzyńska L Wiatr E Wierzbicka M Załeska J Załeska M Zych J Rowińska-Zakrzewska E 《Pneumonologia i alergologia polska》2002,70(5-6):251-257
The aim of this paper is an analysis of clinical documentation and results of autopsy of 21 patients (pts) who died of invasive aspergillosis (IA) in the Institute of Tuberculosis and Chest Diseases in years 1993-2000 and the assessment of predisposing factors for IA. In 17 pts IA was the main and in other 4 only an accessory cause of death. All pts were treated with corticosteroids and/or cytostatic drugs--because of lung cancer (11 pts), cancer in other site (2 pts), haematologic disorders (2 pts), Wegener's granulomatosis (1 pt), polymyositis (1 pt), idiopathic pulmonary fibrosis (1 pt) and other diseases (3 pts). In 15 out of 21 pts granulocytopenia was revealed (from 0.008 x 10(9)/L to 0.82 x 10(9)/L) on an average one month before death. In 15 pts IA was limited to the lungs, in 6 others there were also fungal lesions in brain, kidneys, liver, spleen and heart. Pts with disseminated form of IA had significantly lower granulocyte count and were treated with higher doses of corticosteroids than others. Immunosuppressive drugs and granulocytopenia can be regarded as predisposing factors. Fatal course of IA depended also on the late diagnosis. 相似文献
23.
The double fluorescent retrograde technique was employed to examine the distribution of the inferior olive (IO) neurones projecting to the cortex of the rostral and caudal parts of the paramedian lobule (PML) in the rabbit cerebellum, known to be the face-forelimb and hindlimb receiving areas, respectively. Moreover, this technique was also used to investigate the possibility that IO projections reaching these two somatotopically non-homologous PML regions are collaterals of the same axones. No other reports have addressed this question. After non-overlapping unilateral injections of the cytoplasmic tracer fast blue (FB) and the nuclear dye diamidino yellow (DY) into the rostral and caudal PML, respectively, numerous single FB- or DY-labelled cells were found in the defined regions of the contralateral IO. These regions showed considerable overlap, apart from the dorsal accessory olive where a clear spatial separation of labelled cell groups was observed. Furthermore, double FB + DY-labelled neurones (n = 310) were seen in the medial accessory olive, the dorsal and ventral laminas of the principal olive, in the dorsomedial cell column and the beta nucleus. It suggests that IO neurones may branch to supply the two functionally different PML regions and in this way participate in the mechanisms of forelimb-hindlimb coordination. 相似文献
24.
Lynch G Kohler S Leser J Beil M Garcia-Marin LJ Lutz MP 《Pflügers Archiv : European journal of physiology》2004,448(4):445-451
The aim of this study was to establish whether the rate of fatty acid (FA) incorporation and its utilization by the isolated soleus muscle is modified under conditions of thyroid hormone deficit or excess. The rate of palmitic acid (PA) uptake, oxidation and incorporation into intramuscular lipids with increasing PA concentration (0.5–1.5 mM) in the incubation medium were determined. In hypothyroid rats intramuscular triacylglycerol (TG) synthesis was increased, while the rate of PA oxidation to CO2 and incorporation into mono- and diacylglycerols (MG/DG) and phospholipids (PL) remained unchanged. In rats with triiodothyronine (T3) excess the rate of all processes studied was enhanced, although the percentage incorporation of PA into different classes of intramuscular lipids was fairly constant and, independently of thyroid state and FA concentration in the medium, was 56–66% for TG, 9-14% for MG/DG and 24–32% for PL. Our results thus indicate that even short-term T3 excess accelerates the rate of FA uptake and metabolism in the oxidative soleus muscle, whereas in hypothyroid rats only intramuscular TG synthesis is affected. 相似文献
25.
Maria Janusz Krystyna Starościk Wojciech Gorczyca Zbigniew Wieczorek Józef Lisowski 《Molecular immunology》1983,20(11):1149-1155
The Fc gamma receptor of guinea-pig peritoneal macrophages was purified by affinity chromatography by using rabbit IgG or guinea-pig IgG2 coupled to Sepharose. Lysates prepared by treatment of 125I-labeled macrophages with NP-40 were first applied to BSA-Sepharose and then to IgG-Sepharose and eluted with 0.5 M acetic acid containing 1% NP-40. The specific binding was determined by interaction of the 125I-labeled receptor with IgG-Sepharose in the presence and absence of soluble IgG. The specific binding of the purified receptor was 42-82%. Interactions of the purified receptor with IgG-Sepharose were equally well inhibited by soluble rabbit IgG or guinea-pig IgG2, but not by F(ab')2 fragments. Inclusion of NP-40 in the buffer used in the assay reduced nonspecific binding of the receptor to the affinity gels. The purified receptor can be stored for 20 days at 4 degrees C without a significant loss of the specific binding activity. Analysis of the receptor by SDS-polyacrylamide gel electrophoresis, under nonreducing and reducing conditions, revealed two major peaks of radioactivity corresponding to mol. wts of about 50,000 and 25,000, and one very minor peak corresponding to a mol. wt of about 30,000. The results obtained suggest that the protein of the second major peak is a product of the dissociation of the protein of the first major peak rather than a product of its reduction by 2-mercaptoethanol. 相似文献
26.
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28.
We have determined cutaneous DTH reactions to SK-SD and PPD and peripheral blood lymphocyte profiles in a group of asbestos workers in two consecutive surveys. It was found that asbestosis and, to a lesser extent, the presence of ANA are significantly correlated with the lack of response to the above antigens. 83% of asbestos workers when tested at a 4 year interval fell into the same two categories of responsiveness (lack of response or response at least to one antigen).The asbestosis cases had lower total lymphocyte count as well as proportions and absolute number of E-RFC as compared to asbestos workers without asbestosis and/or ANA. Furthermore, the latter group showed the lower percentages and absolute number of E-RFC than the matched controls. The presence of ANA is also correlated with lower proportions of E-RFC. However, this is related at least in part to asbestosis. 相似文献
29.
Nowak I Pochroń B Kozlowska A Dubis J Kuśnierczyk P 《Archivum immunologiae et therapiae experimentalis》2001,49(6):453-460
We compared HLA antigen expression on new B-lymphoblastoid cell line (B-LCL) HAJ with that on B-LCLs expressing normal HLA levels as well as on B-LCLs derived from bare lymphocyte syndrome (BLS) patients and in vitro mutated B-LCLs of BLS-like phenotype. HAJ cells had no expression of HLA class II and low expression of class I antigens similarly to some of BLS B-LCLs, although HAJ cell line was derived from lymphocytes of HLA class I- and class II-normally expressing donor. HAJ cells displayed B lymphocyte markers, surface immunoglobulin and CD19. Culture of HAJ cells in the presence of interferon y resulted in HLA class I antigen upregulation, but did not restore class II expression. The cell line HAJ may prove useful for studies on factors influencing HLA class I cell surface expression. 相似文献
30.
Sowiska-Klencka D Klencki M Dedecjus M Lewiski A Pawlikowski M 《Endocrine pathology》2000,11(2):173-178
Nucleolar organizer regions (NORs) are segments of DNA, encoding for ribosomal RNA. They are associated with argyrophilic
proteins and, thus, they can be localized through silver staining. A correlation has been shown between the number, the size,
or the intranuclear localization of AgNORs, and the proliferative activity of cells. The aim of this study was to examine
numerous features of AgNORs in pituitary adenomas and to relate them to immunohistochemical typing of tumor. Histologic slides
from 32 pituitary tumors and one normal pituitary were silver-stained and analyzed with a computerized system for microscopic
image analysis, supported by an AgNORmeter95 program. All the tumors were also immunocyto chemically characterized. We have
found that gonadotropinomas, when compared with plurihormonal adenomas, revealed a lower proportion of nuclei with a single
AgNOR and a higher percentage of marginal dots. Recurrent adenomas, when compared with primary adenomas, showed a higher proportion
of nuclei with three AgNOR dots, a larger total area of dots in the nuclei, and a higher standard deviation of the AgNOR dot
area in the nucleus. Adenomas immunopositive for prolactin, when compared with immunonegative ones, showed a larger mean area
of the AgNOR dot, a larger area of the biggest dot in the nucleus, and a higher proportion of nuclei within a single dot.
These results suggest that the estimated parameters of AgNOR dots differ according to tumor aggressiveness and to the hormone
immunopositivity of pituitary adenomas. 相似文献