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61.
Twenty-two rats were reared in standard conditions during the first two months of their life. Then the animals were divided into two groups exposed to different rearing conditions. Twelve animals (Group SO) were housed socially, six animals per cage, and for three weeks they were subjected to sensory stimulation in an enriched environment. The other ten subjects were kept individually (Group IN); one rat per mesh cage, in conditions of relatively impoverished sensory stimulation. In both groups the training of the conditioned emotional response (CER) was performed when animals were three months old. In contrast to IN subjects, the rats subjected to permanent social contacts and reared in the enriched environment (Group SO) revealed almost equally low instrumental response rates in trials with the conditioned stimulus (CS) paired with nociceptive foot-shock (US), and in periods when no CS and/or US were applied. The results suggested that early exposure to an enriched environment caused a later decrease of the animals' capability to differentiate between the aversive CS and cues of the experimental context. This cognitive impairment was probably a secondary effect of fear generalized to the entire experimental situation. 相似文献
62.
Opolski A Laskowska A Madej J Wietrzyk J Kłopocki A Radzikowski C Ugorski M 《Clinical & experimental metastasis》1998,16(8):673-681
Several lines of evidence indicate that sialosyl Le a , tumor-associated carbohydrate antigen present on human colon carcinoma cells, is involved in formation of metastases. To study the role of this carbohydrate structure in development of metastases, we have used the clone of human colon carcinoma CX-1 cells transfected with antisense expression vector containing fragment of cDNA for a1,3/4-fucosyltransferase (FT III), which is involved in synthesis of sialosyl Le a tetrasaccharide. It has been reported previously that, in contrast to the parental cells, the antisense-transfected CX-1.1AS5 cells do not express sialosyl Le a and do not adhere to E-selectin-expressing CHO cells. In the present work we have studied the formation of liver metastases by CX-1.1AS5 cells after their orthotopic or intrasplenic implantation into athymic nu/nu mice. After orthotopic implantation of sialosyl Le a -negative colon carcinoma CX-1.1AS5 cells, the number of mice with liver metas-tases was markedly lower (21% of mice) in comparison with their number after implantation of the parental CX-1.1 cells (86% of mice). However, no differences in ability to form colonies in liver were observed between parental CX-1.1 cells and antisense-transfected CX-1.1AS5 cells after intrasplenic inoculation. The liver metastases were formed in 89% and 84% of mice, respectively. Our data support the thesis on the importance of sialosyl Le a antigen expression in the development of liver metastases by colon cancer cells, and indicate the role of transplantation route and primary tumor localization in formation of metastases.© Kluwer Academic Publishers 1998 相似文献
63.
Płodziszewska M Chorostowska J Polubiec-Kownacka M Jaroń B Lenarcik D Marzinek M Szopiński J Wiatr E Załeska J Zych J Skopińska-Rózewska E Rowińska-Zakrzewska E 《Pneumonologia i alergologia polska》2000,68(11-12):557-565
The aim of this study was to assess how the extent of the number and percentage of lymphocytes in BALF and also the CD4 to CD8 ratio can help to predict the short outcome in sarcoidosis. Material consisted of 74 patients, 39 men and 35 women in the age from 23 to 58 years. 11 patients had chest lesions in stage I, 43 in stage II and 20 in stage III. Clinical markers of activity (fever, erythema nodosum) were present in 22 cases. Extrathoracic lesion were present in 31 and abnormal pulmonary function in 30. In all patients BAL was done before treatment and lymphocyte count, percentage and CD4/CD8 ratio was calculated. 50 patients were treated with corticosteroids and 24 were observed without treatment. After 6-12 month of observation regression of sarcoid lesions was observed in 46 of 50 patients treated with corticosteroids and in 17 out of 24 patients observed without treatment. There were no differences in lymphocyte count and percentage in BALF and in the short term outcome between group treated with corticosteroids and without treatment. The patients in whom regression of lesions was observed have however significantly higher CD4/CD8 ratio than others. 相似文献
64.
Zalewska T Ziemka-Nałecz M Sarnowska A Domańska-Janik K 《Acta neurobiologiae experimentalis》2002,62(2):53-61
Spatial and temporal relations between metalloproteinase (MMP-2 and MMP-9) activation and laminin degradation in gerbil hippocampus after transient cerebral ischemia has been studied. Activity of MMPs was determined by gelatin zymography in homogenates from dorsal (DP, an equivalent of CA1 sector) and abdominal (AbP, containing CA2-4 and gyrus dentatus) parts of hippocampus. A significant activation of both investigated metalloproteinases was found at 72 h of recovery. Whereas MMP-2 up-regulation did not show any spatial preferences, the increase of MMP-9 activity was observed exclusively in DP. Activation of MMP-9 at this time point correlated spatially with degradation of laminin-protein of extracellular matrix. These results show that MMP pathway may function as a component of delayed neuronal death cascade in the apoptogenic CA1 sector after transient global ischemia. 相似文献
65.
The acoustic startle response (ASR) was studied in 20 gray short-tailed opossums (Monodelphis domestica) and its characteristics were compared with those obtained from responses of 20 Wistar albino rats. The animals were exposed to 10 ms, 110 dB white noise acoustic pulses in the Coulbourn apparatus. Amplitude of ASR was normalized to the weight of animals and then analyzed. The results show that probability of a freezing response is much higher in the opossums that generally respond with lower startle amplitudes in comparison to rats. These differences may reflect different emotional characteristics of the two species, different reactions to fear in opossum and/or different ecological specializations of the two species. 相似文献
66.
Klimiuk PA Sierakowski S Domysławska I Fiedorczyk M Chwiećko J 《Archivum immunologiae et therapiae experimentalis》2004,52(1):36-42
INTRODUCTION: The purpose of this study was to determine the effect of repeated infusions of infliximab, a chimeric anti-tumor necrosis factor (anti-TNF)-alpha antibody, on the levels of soluble adhesion molecules and vascular endothelial growth factor (VEGF) in patients with active rheumatoid arthritis (RA). MATERIALS AND METHODS: The treatment design consisted of 9 infusions of infliximab (3 mg/kg) at weeks 0, 2, 6, and every 8 weeks thereafter. All patients had been receiving methotrexate (MTX; 7.5-20 mg/week). Serum levels of soluble intercellular adhesion molecule (sICAM)-1, vascular cell adhesion molecule (sVCAM)-1, E-selectin (sE-selectin), and VEGF were measured by ELISA at weeks 0, 2, 6, 14, and 38 prior to infusion, and at week 62. RESULTS: A remarkable decrease in serum sICAM-1 (p<0.001), sVCAM-1 (p<0.01), sE-selectin (p<0.01) and VEGF (p<0.001) levels was observed in RA patients after the initial dose of infliximab. The second administration of the drug was followed by an even more significant suppression of serum sICAM-1, sVCAM-1, sE-selectin, and VEGF (p<0.001 in all cases). Further infliximab infusions also significantly reduced serum soluble adhesion molecules and VEGF concentrations, although these were less effective. Infliximab treatment induced a significant decrease in the number of monocytes observed until the end of the study. CONCLUSIONS: Our study, besides a rapid suppression of disease activity, showed that serum soluble adhesion molecules and VEGF concentrations are down-regulated following anti-TNF-alpha antibody therapy combined with MTX. Repeated doses of infliximab sustained the reductions in the soluble adhesion molecules and VEGF concentrations, although they were less effective than the first and second infusions of infliximab. 相似文献
67.
68.
Dayan A Feinberg MS Holbova R Deshet N Scheinowitz M 《Annals of clinical and laboratory science》2005,35(1):73-78
The effect of exercise training prior to acute myocardial infarction (AMI) on left ventricular (LV) remodeling is poorly understood. This study investigated the protective effect of 3 weeks of swimming exercise training prior to AMI on cardiac morphology and function. Male Sprague-Dawley rats (n = 35) were randomly assigned to 3 groups: swimming training (n = 14, 90 min, 5 days/wk, 3 wk), sedentary (n =14), and controls (n = 7, no exercise, no MI). At the end of the training/sedentary period, rats were subjected to AMI (ExMI and SedMI) induced by surgical ligation of the left coronary artery. Thereafter, the rats remained sedentary for a 4-wk recovery period. Trans-thoracic echocardiography was performed in each group at the end of the exercise/sedentary period (pre-AMI), 24 hr after AMI, and following recovery (4 wk after AMI). No differences were observed in LV dimensions and function pre-AMI among the 3 groups; however, LV-end systolic diameter (LVESD) and LV-end systolic area (LVES-area) were significantly lower in the prior trained rats, 24 hr post-AMI with no additional change 4 wk post-AMI, during remodeling. Both LV-shortening fraction (SF%) and fractional area change (FAC%) were higher in the trained animals 4 wk post-AMI (39+/-12% vs 23+/-8%; p 0.002, and 48+/-14% vs. 38+/-9%; p 0.07, respectively). In conclusion, 3 wk of swimming exercise training prior to AMI significantly attenuated LV remodeling and improved LV function, despite no changes in LV dimensions or systolic function at the end of the exercise session. The data suggest that even a short-term training period is sufficient to induce cardiac protection. 相似文献
69.
Remiszewski P Słodkowska J Szczepek B Zwolska Z Radomski P Byszewska D Rowińska-Zakrzewska E 《Pneumonologia i alergologia polska》1999,67(7-8):354-361
In 116 out of 845 patients treated for small cell lung cancer (SCLC) in the Institute of Tuberculosis and Chest Disease in Warsaw in the years 1980-1994 infection was the main or coexistent cause of death. In 4.1% infection was proved of bacterial origin and in further 6.5% of probable bacterial origin (in the later group cultures were negative or not done but fungal infection, pneumocystosis pneumonia and tuberculosis were excluded on autopsy). In 1.54% infection was of fungal origin, 1.2% patients died of Pneumocystis carinii pneumonia and 0.35% of tuberculosis. The majority of patients who died with and/or from infection had treatment-related leukopenia and 99 of them were treated with corticosteroids. Fungal infection, pneumocytosis and tuberculosis were found more frequently than bacterial infection in patients treated with cumulative dose of prednisone above 2000 mg. 33.62% patients had no symptoms or signs of infection. No connection was found between the absence of symptoms and treatment with steroids or the grade of leukopenia. In all cases infection was recognised very late, in 58 only at autopsy. 相似文献
70.
U. Sławin´ska F. Tyc˘ S. Kasicki R. Navarrete G. Vrbová 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1998,120(2):193-201
After partial denervation, the remaining motor units (MUs) of adult fast extensor digitorum longus muscle (EDL) expand their
peripheral field. The time course of this event was studied using tension measurement and recordings of electromyographic
(EMG) activity. The results show that after section of the L4 spinal nerve, when only 5.3 ± 0.63 of the 40 MUs normally supplying
EDL muscle remain, the force of individual motor units starts to increase between the 1st and 2nd week after the operation
and continues to do so for a further week. The drastic reduction of the number of motoneurones supplying the fast EDL leads
to an increase in activity of the remaining MUs. In the 1st week after partial denervation, there was a sharp increase in
the EMG activity of remaining motor units. During the next 12 days, this increase became less marked, but EMG activity remained
nevertheless significantly higher than that of the unoperated EDL muscle. Many MUs became tonically active during posture.
The EMG activity pattern during locomotion was also altered, so that the burst duration was positively correlated with the
step cycle duration. Moreover, shortly after partial denervation, the interlimb coordination was disturbed but returned to
its original symmetrical use 1–2 weeks later.
Received: 17 September 1996 / Accepted: 3 November 1997 相似文献