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131.
1引言
所谓抗凝治疗是用适当的药物(即抗凝剂)来抑制血液凝固的控制疗法.抗凝剂在脑缺血治疗中的作用仍处在发展之中.业已证明,没有一种单一的治疗方法能够有效地防治所有类型的脑缺血,包括肝素、肝素类似物和华法林等.尽管抗凝治疗可能会引起出血并发症,但在过去10年中,已经有多项随机对照研究有助于确定哪些患者可能从抗凝治疗中受益. 相似文献
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133.
Keller M Gerbes AL Kulhanek-Heinze S Gerwig T Grutzner U van Rooijen N Vollmar AM Kiemer AK 《World journal of gastroenterology : WJG》2005,11(47):7418-7429
AIM: To determine functional consequences of this activation, whereby we focused on a potential regulation of the hepatocyte cytoskeleton during ischemia and reperfusion. METHODS: For in vivo experiments, animals received ANP (5 μg/kg) intravenously. In a different experimental setting, isolated rat livers were perfused with KH-buffer ±ANP (200 nmol/L)±SB203580 (2 μmol/L). Livers were then kept under ischemic conditions for 24 h, and either transplanted or reperfused. Actin, Hsp27, and phosphorylated Hap27 were determined by Western blotting, p38 MAPK activity by in vitro phosphorylation assay. F-actin distribution was determined by confocal microscopy. RESULTS: We first confirmed that ANP preconditioning leads to an activation of p38 MAPK and observed alterations of the cytoskeleton in hepatocytes of ANP-preconditioned organs. ANP induced an increase of hepatic F-actin after ischemia, which could be prevented by the p38 MAPK inhibitor SB203580 but had no effect on bile flow. After ischemia untreated livers showed a translocation of Hsp27 towards the cytoskeleton and an increase in total Hsp27, whereas ANP preconditioning prohibited translocation but caused an augmentation of Hsp27 phosphorylation. This effect is also mediated via p38 MAPK, since it was abrogated by the p38 MAPK inhibitor SB203580. CONCLUSION: This study reveals that ANP-mediated p38 MAPK activation leads to changes in hepatocyte cytoskeleton involving an elevation of phosphorylated Hsp27 and thereby for the first time shows functional consequences of ANP-induced hepatic p38 MAPK activation. 相似文献
134.
CC chemokine ligand 20 partially controls adhesion of naive B cells to activated endothelial cells under shear stress 总被引:2,自引:0,他引:2 下载免费PDF全文
Meissner A Zilles O Varona R Jozefowski K Ritter U Marquez G Hallmann R Korner H 《Blood》2003,102(8):2724-2727
Chemokines are thought to control lymphocyte recruitment to the inflamed endothelium. To dissect chemokine-mediated adhesion, binding of ex vivo isolated splenocytes to tumor necrosis factor (TNF)-activated endothelial cells was analyzed under shear stress. We observed specific adhesion of naive follicular B cells, which could be blocked by pertussis toxin. This indicated a G protein-mediated binding and pointed at a contribution of chemokine receptors to B-cell adhesion. Analysis of chemokines expressed by TNF-activated endothelial cells showed that CC chemokine ligand 2 (CCL2), CCL17, and CCL20 were up-regulated. Only on follicular B cells was the cognate receptor for CCL20, CC chemokine receptor 6 (CCR6), expressed strongly, and a functional transmigration assay with CCR6-negative B cells demonstrated conclusively the sole signaling of CCL20 through CCR6. Desensitization of CCR6 on naive B cells with CCL20 resulted in receptor down-regulation and reduced B-cell adhesion. We conclude that CCL20 plays a vital role in B-cell adhesion to the inflamed endothelium. 相似文献
135.
Lia Burkhardt Frederic Bachmann Malte Mader Katharina Grupp Till Eichenauer Andreas Becker Meike Adam Markus Graefen Hartwig Huland Stefan Kurtz Stefan Steurer Maria C Tsourlakis Sarah Minner Uwe Michl Thorsten Schlomm Guido Sauter Hüseyin Sirma 《The Journal of pathology》2013,231(1):130-141
Deletion of 3p13 has been reported from about 20% of prostate cancers. The clinical significance of this alteration and the tumour suppressor gene(s) driving the deletion remain to be identified. We have mapped the 3p13 deletion locus using SNP array analysis and performed fluorescence in situ hybridization (FISH) analysis to search for associations between 3p13 deletion, prostate cancer phenotype and patient prognosis in a tissue microarray containing more than 3200 prostate cancers. SNP array analysis of 72 prostate cancers revealed a small deletion at 3p13 in 14 (19%) of the tumours, including the putative tumour suppressors FOXP1, RYBP and SHQ1. FISH analysis using FOXP1‐specific probes revealed deletions in 16.5% and translocations in 1.2% of 1828 interpretable cancers. 3p13 deletions were linked to adverse features of prostate cancer, including advanced stage (p < 0.0001), high Gleason grade (p = 0.0125), and early PSA recurrence (p = 0.0015). In addition, 3p13 deletions were linked to ERG+ cancers and to PTEN deletions (p < 0.0001 each). A subset analysis of ERG+ tumours revealed that 3p13 deletions occurred independently from PTEN deletions (p = 0.3126), identifying tumours with 3p13 deletion as a distinct molecular subset of ERG+ cancers. mRNA expression analysis confirmed that all 3p13 genes were down regulated by the deletion. Ectopic over‐expression of FOXP1, RYBP and SHQ1 resulted in decreased colony‐formation capabilities, corroborating a tumour suppressor function for all three genes. In summary, our data show that deletion of 3p13 defines a distinct and aggressive molecular subset of ERG+ prostate cancers, which is possibly driven by inactivation of multiple tumour suppressors. Copyright © 2013 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献
136.
Rainer Haak Juliane Siegner Dirk Ziebolz Uwe Blunck Sabine Fischer Jan Hajtó Roland Frankenberger Felix Krause Hartmut Schneider 《Dental materials》2021,37(3):423-431
ObjectivesIn-vitro evaluation of the influence of preparation design and thickness of ceramic veneers on the interfacial bond using optical coherence tomography (OCT).MethodsSixty-four central incisors were randomly assigned to four preparation designs differing from no to complete dentine exposure (n = 16 each): non-prep (NP), minimal-invasive (MI, no dentine exposure), semi-invasive (SI, 50% dentine) and invasive (I, 100% dentine). Ceramic veneers (IPS InLine Veneer) of two thicknesses (0.2?0.5 mm (T1) and > 0.5–1.2 mm (T2)) were etched, silanized, and adhesively luted (Optibond FL, Variolink Veneer). After water storage (37 °C, 21d), thermocycling (2000 cycles, 5°-55 °C), and mechanical loading (2 + 1 million cycles, 50 + 100 N) specimens were imaged by spectral-domain OCT (Telesto II, Thorlabs). Adhesive defects at the ceramic-composite and tooth-composite interfaces were quantified on 35 equidistantly distributed OCT B-scans (length, %). Statistical differences were verified with Wilcoxon-/Mann-Whitney-U-test (α = 0.05).ResultsAdhesive defects appeared in all groups at both interfaces, albeit to differing extents (0.1 – 31.7%). NP and MI veneers showed no significant differences at the interfaces (pi > 0.05). In groups, SI and I, significantly more adhesive defects appeared at the tooth-composite compared to the veneer-composite interface (pi ≤ 0.039). The following preparation designs and veneer thicknesses showed differences (pi ≤ 0.021): Veneer-composite: NP-T1 < I-T1, MI-T1 < I-T1, I-T1 > I-T2; Tooth-composite: NP-T1 < SI-T1, NP-T1 < I-T1, NP-T2 > MI-T2, MI-T1 < SI-T1, MI-T1 < I-T1, SI-T1 < I-T1, MI-T2 < SI-T2, MI-T2 < I-T2.SignificanceThe interface adhesion of ceramic veneers was influenced by the preparation design and the veneer thickness. A ceramic thickness of at least 0.5 mm and a preparation without exposing dentine is advantageous for the interfacial bond. 相似文献
137.
Chirag Nepal Yavor Hadzhiev Christopher Previti Vanja Haberle Nan Li Hazuki Takahashi Ana Maria M. Suzuki Ying Sheng Rehab F. Abdelhamid Santosh Anand Jochen Gehrig Altuna Akalin Christel E.M. Kockx Antoine A.J. van der Sloot Wilfred F.J. van IJcken Olivier Armant Sepand Rastegar Craig Watson Uwe Str?hle Elia Stupka Piero Carninci Boris Lenhard Ferenc Müller 《Genome research》2013,23(11):1938-1950
138.
Miersch Sarah König Andreas Mehlhorn Sebastian Fuchs Florian Hahnel Sebastian Rauch Angelika 《Clinical oral investigations》2020,24(9):3009-3016
Clinical Oral Investigations - The aim of this study was to analyse the impact of different clinical conditioning approaches and an ammonium polyfluoride- and trimethoxysilylpropyl... 相似文献
139.
140.
ER Stress During the Pubertal Growth Spurt Results in Impaired Long‐Bone Growth in Chondrocyte‐Specific ERp57 Knockout Mice 下载免费PDF全文
Andrea Linz Yvonne Knieper Tobias Gronau Uwe Hansen Attila Aszodi Natalio Garbi Günter J Hämmerling Thomas Pap Peter Bruckner Rita Dreier 《Journal of bone and mineral research》2015,30(8):1481-1493
Long‐bone growth by endochondral ossification is cooperatively accomplished by chondrocyte proliferation, hypertrophic differentiation, and appropriate secretion of collagens, glycoproteins, and proteoglycans into the extracellular matrix (ECM). Before folding and entering the secretory pathway, ECM macromolecules in general are subject to extensive posttranslational modification, orchestrated by chaperone complexes in the endoplasmic reticulum (ER). ERp57 is a member of the protein disulfide isomerase (PDI) family and facilitates correct folding of newly synthesized glycoproteins by rearrangement of native disulfide bonds. Here, we show that ERp57‐dependent PDI activity is essential for postnatal skeletal growth, especially during the pubertal growth spurt characterized by intensive matrix deposition. Loss of ERp57 in growth plates of cartilage‐specific ERp57 knockout mice (ERp57 KO) results in ER stress, unfolded protein response (UPR), reduced proliferation, and accelerated apoptotic cell death of chondrocytes. Together this results in a delay of long‐bone growth with the following characteristics: (1) enlarged growth plates; (2) expanded hypertrophic zones; (3) retarded osteoclast recruitment; (4) delayed remodeling of the proteoglycan‐rich matrix; and (5) reduced numbers of bone trabeculae. All the growth plate and bone abnormalities, however, become attenuated after the pubertal growth spurt, when protein synthesis is decelerated and, hence, ERp57 function is less essential. © 2015 American Society for Bone and Mineral Research. 相似文献