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排序方式: 共有1961条查询结果,搜索用时 15 毫秒
61.
Primary primitive neuroectodermal tumor of the spinal cord: case report and review of the literature. 总被引:6,自引:0,他引:6
Christian Mawrin Hans J Synowitz Elmar Kirches Evelyn Kutz Knut Dietzmann Serge Weis 《Clinical neurology and neurosurgery》2002,104(1):36-40
We present the clinical, radiological, and pathological features of a primary primitive neuroectodermal tumor (PNET) that occurred in the thoracic spinal cord of a 69-year-old man. Magnetic resonance imaging (MRI) demonstrated on T1-weighted images a 2x1x5 cm isointense intraspinal mass with homogeneous contrast enhancement extending from the C7 to the Th3 level. There was no clinical or radiological evidence for the existence of an intracranial tumor. Histological examination revealed a small round cell tumor with rosette formation and immunohistochemical characteristics of a PNET. The patient is the oldest among the 20 cases with this rare spinal cord neoplasm reported so far in the literature; the previously published cases are briefly reviewed. 相似文献
62.
Although the Werther effect is well known, up to now a correlation between the differential distribution of particular media reports and subsequent imitational suicides could not be found. This study investigates a celebrity suicide by gun in Austria, which led to extensive reports in the largest Austrian newspaper, whose distribution shows substantial regional differences. The numbers of suicides by firearm in the 3 weeks after the reporting showed an increase over the 3 weeks prior. Regional analysis revealed a strong correlation of suicides by firearm and distribution of the newspaper (log odds ratios; r(9) = .62; p = .04, one-tailed). This dose-response effect explains 40% of the variability of changes. These results underline the influence of media reports on suicidal behavior. 相似文献
63.
Ingelore Gehlen Lutz Netuschil Thomas Georg Elmar Reich Rolf Berg Christos Katsaros 《Journal of orofacial orthopedics》2000,58(5):138-148
In a prospective plaque regrowth study focusing on oral hygiene during fixed appliance therapy 12 adolescent patients (mean age 14.1±1.5 years) were evaluated twice over 2-day test periods. In the randomized, double-blind study the influences of a 0.2% chlorhexidine mouthrinse (Corsodyl®, CHX) and a commercially available dentrifice supplementing fluoride (Odol-med-3®) were compared intra- and interindividually in a crossover design with regard to the bacteriological parameters. The bacteriological parameters of vital fluorescence, bacteriological counts (BC), colony forming units (CFU), plating efficiency (PE) and mutans streptococci (MS) were related to the clinically assessed indices of plaque and gingivitis.All parameters analyzed demonstrated significant differences between the control and the test (chlorhexidine) group. Where-as the values of BC, CFU, and PE progressively increased in the control group from T0 to T2, these parameters distinctly decreased in the chlorhexidine group. All values of vital flora (VF) scored around 75% in the control group compared to values of 30% in the test group. BC, CFU und PE correlated significantly. The score of mutans streptococci persisted or increased in the controls whereas mutans streptococci approached 0 in the chlorhexidine group. Until the 5th day of washout a clear-cut carry over of the chlorhexidine rinse on mutans streptococci as well as on the gingival index was evident. 相似文献
64.
OBJECTIVES: Toothpastes are good vehicles for antibacterial substances to exert a prolonged effect. This effect depends on the substantivity and ability to interfere with plaque metabolism and/or vitality. It was the purpose of this clinical, randomized 2 x 4 cell crossover study to evaluate and to compare the antibacterial effects of two toothpastes (Colgate Total(R), COL and Parodontax(R), PAR) applied as slurries on established plaque over 24 h (Part I) and their effect on 4-day plaque regrowth (Part II). Chlorhexamed(R) (0.1%; CHX) and water served as positive and negative controls. MATERIAL AND METHODS: After professional toothcleaning eight students were asked to refrain from all mechanical hygiene measures for the next 72 h. After 48 h plaque was sampled and vitality of the plaque flora examined (baseline, VF0%). The subjects then rinsed for 1 min with 15 mL of one of the test or control solutions. Every second hour up to 14 h and 24 h after rinsing, plaque sampling and staining was performed to assess plaque vitality (VF2-24, Part I). In Part II, the classical 4-day plaque regrowth design was used with two rinses (1 min) a day as the only oral hygiene measure. Vitality values were assessed on day 1 and day 4 (VF1, VF2). At day 4, teeth were stained to assess the whole mouth plaque index (PlI) and to evaluate the percentage of plaque area (PA) of the anterior teeth. RESULTS: Compared to placebo, all active rinses reduced plaque vitality significantly over a period of 24 h (Part I). PAR, COL and CHX revealed reductions of 18-31%, 28-50% and 19-50%, respectively. In Part II, similar reductions of all parameters were found for all active rinses (PAR 12-30%, COL 34-51%, CHX 40-64%). CONCLUSIONS: Colgate Total has shown a significant action on plaque regrowth and a high substantivity during 24 h, while Parodontax revealed a more moderate but still significant effect. 相似文献
65.
66.
Shahab-Osterloh S Witte F Hoffmann A Winkel A Laggies S Neumann B Seiffart V Lindenmaier W Gruber AD Ringe J Häupl T Thorey F Willbold E Corbeau P Gross G 《Stem cells (Dayton, Ohio)》2010,28(9):1590-1601
Ligament-to-bone and tendon-to-bone interfaces (entheses, osteotendinous junctions [OTJs]) serve to dissipate stress between soft tissue and bone. Surgical reconstruction of these interfaces is an issue of considerable importance as they are prone to injury and the integration of bone and tendon/ligament is in general not satisfactory. We report here the stem cell-dependent spontaneous formation of fibrocartilaginous and fibrous entheses in heterotopic locations of the mouse if progenitors possess a tenogenic and osteo-/chondrogenic capacity. This study followed the hypothesis that enhanced Bone Morphogenetic Protein (BMP)-signaling in adult mesenchymal stem cells that are induced for tendon formation may overcome the tendon-inherent interference with bone formation and may thus allow the stem cell-dependent formation of tendon-bone interfaces. The tenogenic and osteo-/chondrogenic competence was mediated by the adeno- and/or lentiviral expression of the biologically active Smad8 signaling mediator (Smad8ca) and of Bone Morphogenetic Protein 2 (BMP2). Modified mesenchymal progenitors were implanted in subcutaneous or intramuscular sites of the mouse. The stem cell-dependent enthesis formation was characterized histologically by immunohistological approaches and by in situ hybridization. Transplantation of modified murine stem cells resulted in the formation of tendinous and osseous structures exhibiting fibrocartilage-type OTJs, while, in contrast, the viral modification of primary human bone marrow-derived mesenchymal stromal/stem cells showed evidence of fibrous tendon-bone interface formation. Moreover, it could be demonstrated that Smad8ca expression alone was sufficient for the formation of tendon/ligament-like structures. These findings may contribute to the establishment of stem cell-dependent regenerative therapies involving tendon/ligaments and to the improvement of the insertion of tendon grafts at bony attachment sites, eventually. 相似文献
67.
Florian Stehling Ralph Weber Arzu Özcelik Martina Bröcker Lothar Volbracht Hans-Christoph Diener Elmar Busch 《Neuroscience letters》2008
Thrombolysis is the only effective pharmaceutical therapy in acute ischemic stroke in humans but has a high risk of intracerebral hemorrhage. We aimed to establish an animal model to study changes of coagulation and fibrinolytic parameters during thromboembolic ischemic stroke and thrombolysis with recombinant tissue plasminogen activator (rt-PA). We used a thromboembolic stroke model in the rat. Animals were treated with rt-PA thrombolysis (n = 10) and compared with untreated (n = 10), sham operated (n = 10) and control animals (n = 20). Coagulation parameters (APTT, PT, TT, fibrinogen, AT III, TAT) and fibrinolytic parameters (t-PA antigen concentration, t-PA activity, PAI-1 concentration, PAI activity, plasminogen, antiplasmin) were measured at two time points (2.5 and 5 h after stroke induction) with a battery of commercially available test kits. We observed an (1) initiation of coagulation and inhibition of fibrinolysis by the operation procedure itself, (2) simultaneous activation of fibrinolysis and its inhibitors after stroke induction and (3) potent initiation of fibrinolysis and consumption of fibrinolysis inhibitors after rt-PA therapy of stroke. We established a model system to monitor coagulation and fibrinolysis during thrombolytic therapy of stroke in the rat. This model may be used to study the influence of these parameters on hemorrhagic stroke transformation and outcome in experimental stroke in future. 相似文献
68.
Stehling F Weber R Ozcelik A Bröcker M Volbracht L Diener HC Busch E 《Neuroscience letters》2008,442(1):39-43
Thrombolysis is the only effective pharmaceutical therapy in acute ischemic stroke in humans but has a high risk of intracerebral hemorrhage. We aimed to establish an animal model to study changes of coagulation and fibrinolytic parameters during thromboembolic ischemic stroke and thrombolysis with recombinant tissue plasminogen activator (rt-PA). We used a thromboembolic stroke model in the rat. Animals were treated with rt-PA thrombolysis (n=10) and compared with untreated (n=10), sham operated (n=10) and control animals (n=20). Coagulation parameters (APTT, PT, TT, fibrinogen, AT III, TAT) and fibrinolytic parameters (t-PA antigen concentration, t-PA activity, PAI-1 concentration, PAI activity, plasminogen, antiplasmin) were measured at two time points (2.5 and 5h after stroke induction) with a battery of commercially available test kits. We observed an (1) initiation of coagulation and inhibition of fibrinolysis by the operation procedure itself, (2) simultaneous activation of fibrinolysis and its inhibitors after stroke induction and (3) potent initiation of fibrinolysis and consumption of fibrinolysis inhibitors after rt-PA therapy of stroke. We established a model system to monitor coagulation and fibrinolysis during thrombolytic therapy of stroke in the rat. This model may be used to study the influence of these parameters on hemorrhagic stroke transformation and outcome in experimental stroke in future. 相似文献
69.
Bianca Dimitrov Nastassja Himmelreich Agnes L. Hipgrave Ederveen Christian Lüchtenborg Jürgen G. Okun Maximilian Breuer Anna-Marlen Hutter Matthias Carl Luca Guglielmi Andrea Hellwig Kai Christian Thiemann Markus Jost Verena Peters Christian Staufner Georg F. Hoffmann Annette Hackenberg Nagarajan Paramasivam Stefan Wiemann Christian Thiel 《Molecular genetics and metabolism》2018,123(3):364-374
Congenital disorders of glycosylation (CDG) are genetic defects in the glycoconjugate biosynthesis. > 100 types of CDG are known, most of them cause multi-organ diseases. Here we describe a boy whose leading symptoms comprise cutis laxa, pancreatic insufficiency and hepatosplenomegaly. Whole exome sequencing identified the novel hemizygous mutation c.542 T > G (p.L181R) in the X-linked ATP6AP1, an accessory protein of the mammalian vacuolar H+-ATPase, which led to a general N-glycosylation deficiency. Studies of serum N-glycans revealed reduction of complex sialylated and appearance of truncated diantennary structures. Proliferation of the patient's fibroblasts was significantly reduced and doubling time prolonged. Additionally, there were alterations in the fibroblasts' amino acid levels and the acylcarnitine composition. Especially, short-chain species were reduced, whereas several medium- to long-chain acylcarnitines (C14-OH to C18) were elevated. Investigation of the main lipid classes revealed that total cholesterol was significantly enriched in the patient's fibroblasts at the expense of phophatidylcholine and phosphatidylethanolamine. Within the minor lipid species, hexosylceramide was reduced, while its immediate precursor ceramide was increased. Since catalase activity and ACOX3 expression in peroxisomes were reduced, we assume an ATP6AP1-dependent impact on the β-oxidation of fatty acids. These results help to understand the complex clinical characteristics of this new patient. 相似文献
70.
Andres Schmidt-Hebbel Carlos Gomez Carolina Aviles Elmar Herbst Maximiliano Scheu Gonzalo Ferrer Gonzalo Espinoza 《The Knee》2018,25(6):1129-1133