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排序方式: 共有1913条查询结果,搜索用时 15 毫秒
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Kaczmarek E Erb L Koziak K Jarzyna R Wink MR Guckelberger O Blusztajn JK Trinkaus-Randall V Weisman GA Robson SC 《Thrombosis and haemostasis》2005,93(4):735-742
Extracellular nucleotides bind to type-2 purinergic/pyrimidinergic (P2) receptors that mediate various responses, such as cell activation, proliferation and apoptosis, implicated in inflammatory processes. The role of P2 receptors and their associated signal transduction pathways in endothelial cell responses has not been fully investigated. Here, it is shown that stimulation of human umbilical vein endothelial cells (HUVEC) with extracellular ATP or UTP increased intracellular free calcium ion concentrations ([Ca(2+)](i)), induced phosphorylation of focal adhesion kinase (FAK), p130(cas) and paxillin, and caused cytoskeletal rearrangements with consequent cell migration. Furthermore, UTP increased migration of HUVEC in a phosphatidylinositol 3-kinase (PI3-K)-dependent manner. BAPTA or thapsigargin inhibited the extracellular nucleotide-induced increase in [Ca(2+)](i), a response crucial for both FAK phosphorylation and cell migration. Furthermore, long-term exposure of HUVEC to ATP and UTP, agonists of the G protein-coupled P2Y2 and P2Y4 receptor subtypes, caused upregulation of alpha(v) integrin expression, a cell adhesion molecule known to directly interact with P2Y2 receptors. Our results suggest that extracellular nucleotides modulate signaling pathways in HUVEC influencing cell functions, such as cytoskeletal changes, cellular adhesion and motility, typically associated with integrin-activation and the action of growth factors. We propose that P2Y2 and possibly P2Y4 receptors mediate those responses that are important in vascular inflammation, atherosclerosis and angiogenesis. 相似文献
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Kalisińska E 《Brain, behavior and evolution》2005,65(4):244-261
The size of the brain and its macro-anatomical parts in 206 birds representing 19 anseriform species and 4 tribes (Anserini, Anatini, Aythyini and Mergini) was the subject of a comparative analysis. The comparisons involved two aspects: taxonomic (differences among species within tribes and differences among tribes) and ecological (diet composition: vegetation, invertebrates, or fish and the foraging mode: browsing, dabbling, shallow diving, and deep diving). The relative size of the encephalon (E) and its parts (optic tectum, OT; cerebellum, C; brain stem, BS; hemispheres, H) were described using appropriate indices. Five of them, called the cerebral-body indices (E/BW, OT/BW, C/BW, BS/BW, H/BW), involved a ratio between the weight of E or its parts and that of the body (BW). Four intracerebral indices (OT/E, C/E, BS/E, H/E) and allometric equations were used as well. Almost all the indices showed a high intraspecific variability within the Anserini and Mergini; on the other hand, the intracerebral indices did not differ between the species of the Anatini and Aythyini (except for OT/E in the Aythyini). Between-tribe differences were reflected in all 9 indices. The birds feeding on different diets were found to differ in their OT/E and H/E. The herbivorous anserifom OT/E was clearly lower than that of those birds feeding on invertebrates and fish. The highest OT/E was that of the piscivorous birds. In terms of foraging mode, significant differences were revealed in 7 out of the 9 indices used (differences in OT/BW and C/BW proved non-significant). OT/E of the browsing birds was clearly lower than that of the deep diving ducks; BS/E of the browsers was much lower than that of the dabbling and shallow diving ducks. Geese and swans (browsers) showed much higher H/E compared to the deep diving sea ducks. The latter revealed the highest C/E, but significant differences were detected only in comparison with C/E of the shallow diving ducks. The taxonomic (among tribes) and ecological comparisons showed more differences in the intracerebral indices than in the cerebral-body indices. 相似文献
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Krajewska K Krajewska-Kułak E Lukaszuk C Rolka H Lach J Karczewski J 《Ginekologia polska》2004,75(6):451-456
OBJECTIVES: Assessment of the incidence of fungal pathogens in air of the operating rooms from one of the hospitals in Bia?ystok. MATERIAL AND METHODS: Investigations were conducted in selected rooms of obstetrics department. Material for mycological studies was air sampled at the entrance of hospital building, the entrance to operating room, hall and selected rooms of the department. Fungi were identified using the standard microbial procedures: The monitoring of airborne fungi pollution was done using SAS SUPER 100 (pbi international). Classification of the isolated fungi was done with an accordance to the current procedures. RESULTS: In the air of 16 rooms of obstetrics department different numbers of fungal colonies from 0 to 560 CFU/1000L of air were isolated. Fungi were not isolated from the air samples of preparing, septic, operating and family deliveries rooms. The highest number of fungi colonies were isolated at the entrance the hospital. The following fungal pathogens isolated from the air were: Candida albicans. non-Candida albicans, Penicillium species, Cladosporium species and Aspergillus species. CONCLUSIONS: 1. The different number of fungal colonies was found depending on type of the hospital room. 2. The highest number of fungal colonies was isolated from the air samples of patients rooms 3. No fungal colonies were isolated from the septic, operating and family deliveries rooms 4. The main fungal pathogen isolated from the air samples was Candida albicans. 相似文献
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Karmowski A Sobiech KA Majda J Karmowski M Markuszewski M Kwietniak G Kotarska E Wronecki K 《Ginekologia polska》2004,75(11):847-852
OBJECTIVES: In the blood serum from women divided into 4 groups (healthy women aged 24 and 45 years and patients after the gynaecological surgery with sparing or radical resection of uterus) the lipids index (WL) was determined. MATERIAL AND METHODS: The WL index expresses the correlations among the HDL, LDL, triglycerides and A1 and B apolipoproteins. In the perimenopausal period in women the decrease in the lipids index WL was observed comparing to the women at age of 25. RESULTS: During the diseases indicated the necessity of gynecological surgery in women in the perimenopausal period further decrease in the lipids index WL was noticed. Contrary to the sparing operation, surgical intervention with radical resection of uterus causes the following WL decrease observed in 3rd month after it. CONCLUSION: It may suggest that these differences have hormonal background. 相似文献