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排序方式: 共有552条查询结果,搜索用时 46 毫秒
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Dissociating neural correlates for nouns and verbs 总被引:5,自引:0,他引:5
Shapiro KA Mottaghy FM Schiller NO Poeppel TD Flüss MO Müller HW Caramazza A Krause BJ 《NeuroImage》2005,24(4):407-1067
Dissociations in the ability to produce words of different grammatical categories are well established in neuropsychology but have not been corroborated fully with evidence from brain imaging. Here we report on a PET study designed to reveal the anatomical correlates of grammatical processes involving nouns and verbs. German-speaking subjects were asked to produce either plural and singular nouns, or first-person plural and singular verbs. Verbs, relative to nouns, activated a left frontal cortical network, while the opposite contrast (nouns-verbs) showed greater activation in temporal regions bilaterally. Similar patterns emerged when subjects performed the task with pseudowords used as nouns or as verbs. These results converge with findings from lesion studies and suggest that grammatical category is an important dimension of organization for knowledge of language in the brain. 相似文献
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Nano-carriers for DNA delivery to the lung based upon a TAT-derived peptide covalently coupled to PEG-PEI. 总被引:9,自引:0,他引:9
E Kleemann M Neu N Jekel L Fink T Schmehl T Gessler W Seeger T Kissel 《Journal of controlled release》2005,109(1-3):299-316
Gene therapy aimed at the respiratory epithelium holds therapeutic potential for diseases such as cystic fibrosis and lung cancer. Polyethylenimine (PEI) has been utilized for gene delivery to the airways. In this study, we describe a new modification of PEI, in which an oligopeptide related to the protein transduction domain of HIV-1 TAT was covalently coupled to 25 kDa PEI (PEI) through a heterobifunctional polyethylenglycol (PEG) spacer resulting in a TAT-PEG-PEI conjugate. Improved DNA reporter gene complexation and protection was observed for small (approximately 90 nm) polyplexes as well as significantly improved stability against polyanions, Alveofact, bronchial alveolar lining fluid and DNase. To determine polyplex toxicity in vitro, MTT assays were performed and, for in vivo testing, the mice bronchial alveolar lavage was investigated for total cell counts, quantity of neutrophils, total protein and TNF-alpha concentration. All parameters suggest significantly lower toxicity for TAT-PEG-PEI. Transfection efficiencies of both PEI and TAT-PEG-PEI polyplexes with DNA were studied under in vitro conditions (A549) and in mice after intratracheal instillation. While luciferase expression in A549 cells was much lower for TAT-PEG-PEI (0.2 ng/mg protein) than for PEI (2 ng/mg), significantly higher transfection efficiencies for TAT-PEG-PEI were detected in mice. Reporter gene expression was distributed through bronchial and alveolar tissue. Thus, TAT-PEG-PEI represents a new approach to non-viral gene carriers for lung therapy, comprising protection for plasmid DNA, low toxicity and significantly enhanced transfection efficiency under in vivo conditions. 相似文献
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Ralf Czymek Stefan Limmer Markus Kleemann Philipp Hildebrand Andreas Schmidt Thomas Jungbluth Uwe Roblick Peter Kujath Hans-Peter Bruch 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2009,394(3):517-527
Background In the past, women with Crohn’s disease (CD) as a risk factor in pregnancy were discouraged from becoming pregnant. Today,
by contrast, gestation is medically acceptable in these patients despite several severe complications.
Materials and methods We present the course of five female patients with CD requiring surgery during pregnancy and giving birth at our institution
between 1998 and 2008. These cases as well as our treatment recommendations for patients wishing to have children and our
approaches to the management of complications during pregnancy are discussed in the light of the literature.
Results and conclusion Three of five women had a preterm delivery (26 to 31 weeks’ gestation) with a decreased neonatal weight. Generally, the diagnosis
of CD is often delayed and diagnostic errors (four of five women) are not uncommon. The symptoms vary widely and include those
typical of pregnancy. Three patients had to have a cesarean and only two patients were able to deliver vaginally. Especially
in pregnant patients, the course of the disease is highly variable and difficult to predict. Our experience suggests that
patients should be advised to conceive during remission. Indications for surgery in pregnant patients are the same as for
nonpregnant women and include perforation, obstruction, hemorrhage, and abscess. The advantages of endoscopic surgery also
apply to pregnant patients with acute manifestations. A stoma is not a contraindication to vaginal delivery. 相似文献
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Laparoscopic radiofrequency ablation of unresectable hepatic malignancies: indication, limitation and results 总被引:2,自引:0,他引:2
Hildebrand P Kleemann M Roblick U Mirow L Birth M Bruch HP 《Hepato-gastroenterology》2007,54(79):2069-2072
BACKGROUND/AIMS: Radiofrequency-ablation (RFA) is an effective therapeutic option for destruction of irresectable primary and secondary liver tumors and has been successfully performed transcutaneously using sonographic or computer tomographic guidance or by laparotomy. The laparoscopic approach combines a minimal invasiveness with optimal diagnosis. METHODOLOGY: Between 02/2003 and 10/2005, 14 patients with a total of 45 unresectable liver tumors were treated with laparoscopic radiofrequency-ablation in our hospital. Laparoscopic RFA was primarily performed in patients' superficial lesions adjacent to neighboring organs that could be displaced by laparoscopic maneuvers, deep-sited lesions with a very difficult or impossible percutaneous approach and in combination with other laparoscopic operations. RESULTS: All intrahepatic tumors could be detected safely by laparoscopic intraoperative ultrasound. Additional liver lesions were identified in 5 (35.7%) of the 14 patients. All 45 tumors of the 14 patients were able to be completely ablated. Laparoscopic RFA yielded no mortality and only one case of postoperative bleeding. During a mean follow-up period of 23.2 months one patient locally recurred, three patients had new malignant nodules and two patients died with disease. CONCLUSIONS: Laparoscopic RFA is safe and provides a minimally invasive procedure with the option of simultaneous inflow-occlusion during thermoablation. Even more, neighboring organs can be protected, simultaneous resections can be performed and intraoperative ultrasound is used to gain further diagnosis. 相似文献
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Hsu CC Chiang CW Cheng HC Chang WT Chou CY Tsai HW Lee CT Wu ZH Lee TY Chao A Chow NH Ho CL 《Oncogene》2011,30(6):654-667
Oncofetal genes are expressed in embryos or fetuses, are downregulated or undetectable in adult tissues, and then re-expressed in tumors. Known oncofetal genes, such as AFP, GCB, FGF18, IMP-1 and SOX1, often have important clinical applications or pivotal biological functions. To find new oncofetal-like genes, we used the public information of expressed sequence tags to systematically analyze gene expression patterns and identified a novel oncofetal-like gene, LRRC16B. It increased the proliferation, anchorage-independent growth and tumorigenesis of transformed cells in xenografts, possibly through its effects on cyclin B1 protein levels. These findings exemplify the feasibility of using bioinformatics to find new oncofetal-like genes and suggest that more genes with important functional roles will be uncovered in the candidate gene list. 相似文献
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