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排序方式: 共有2181条查询结果,搜索用时 15 毫秒
1.
Sundaram Kavin Piuzzi Nicolas S. Patterson Brendan M. Stearns Kim L. Krebs Viktor E. Mont Michael A. 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》2020,30(3):447-453
European Journal of Orthopaedic Surgery & Traumatology - The goals of this study were to compare patient satisfaction and wound-related complications in patients receiving 2-octyl cyanoacrylate... 相似文献
2.
Silvia Samarin Lovric Viktor Avbelj Roman Trobec Darko Zorman Peter Rakovec Sergej Hojker Borut Gersak Metka Milcinski 《European journal of cardio-thoracic surgery》2004,26(4):736-741
OBJECTIVE: Complete allograft denervation occurs during heart transplantation. Partial ventricular sympathetic reinnervation may develop one year or later after transplantation and can be measured with iodine-123-meta-iodobenziylguanidine (MIBG) uptake. Aim of this study was to assess sinus node sympathetic reinnervation measured with heart rate variability and ventricular sympathetic reinnervation evaluated with MIBG. METHODS: Twelve patients and 14 healthy controls were included. In patients, MIBG scintigraphy with early and late imaging was performed. Heart to mediastinum ratio (HMR) was calculated and patients were divided in groups with (HMR>1.3) and without left ventricular reinnervation (HMR<1.3). Bipolar ECG with high sampling rate and resolution was recorded over 8.5 min in supine position and in upright position after 10 min interval. R-R intervals in time domain and heart rate variability in frequency domain through spectral power analysis of R-R intervals were analysed to evaluate sinus node reinnervation. Spectral power in low frequency range (0.04-0.15 Hz) above 4.5 ms(2) was considered as sinus node sympathetic reinnervation. RESULTS: Six (50%) patients had evidence of left ventricular sympathetic reinnervation on scintigraphy. Sinus node sympathetic reinnervation based on heart rate variability was detected in 6 (50%) patients in supine, and in 4 (33%) patients in upright body position. Four patients groups were discerned: (1) with ventricular and sinus node sympathetic reinnervation, (2) with sinus node sympathetic reinnervation, (3) with ventricular sympathetic reinnervation and (4) without atrial or ventricular sympathetic reinnervation. Ventricular reinnervation process was time dependent and sinus node reinnervation was not. CONCLUSIONS: Simultaneous ventricular sympathetic reinnervation assessed by MIBG and sinus node sympathetic reinnervation assessed by heart rate variability in supine as in upright position were detected only in two patients (17%). The results of our study show that eventual sinus node sympathetic reinnervation and left ventricular sympathetic reinnervation do not occur simultaneously. 相似文献
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Eduardo Martínez-Soria Viktor Steimle Charlotte Burkhardt Pascale Beffy Jean-Marie Tiercy Jrg T. Epplen Bernard Mach Claude Irl 《Human immunology》1994,40(4)
The T-cell recognition of HLA-DR-peptide complexes is generally restricted by the polymorphism of the DRB molecules but pluriallelic restriction has been described. The molecular basis of restriction and promiscuity of such peptide-specific responses is poorly understood. We isolated a panel of T-cell lines specific for the tetanus toxin peptide p2 (TT830-843) exhibiting pluriallelic restriction by DR11 and DR8 alleles. Fine restriction specificity of the T-cell lines was examined in functional assays against DR oligotyped APCs expressing different variants of DR11 and DR8 alleles. Our results show that (a) polymorphisms between serologically related alleles are relevant in terms of restriction of the peptide-specific T-cell response; in some instances, a single amino acid substitution can determine the restriction of a T-cell line; (b) different patterns of restriction are not the result of specific differences in DR-p2 binding as p2 peptide binds to all DR11 and DR8 alleles tested (DRB1* 1101, -1102, -1103, -1104, 110X, -0801, -0802, -0803, and -0806); and (c) pluriallelic restriction of the peptide-specific T-cell responses correlates with the presence of a DRB1 α-helix motif (67-71-86) shared by some DR11 and DR8 alleles. Possible implications of pluriallelic restriction of peptide-specific T-cell response in autoimmune disorders associated with DR11 and DR8 are discussed. 相似文献
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The median raphe nucleus (MRN) is the primary source of serotonergic afferents to the limbic system that are generally considered to suppress hippocampal theta oscillations. GABA receptors are expressed in the MRN by serotonergic and nonserotonergic cells, including GABAergic and glutamatergic neurons. This study investigated the mechanisms by which the fluctuating GABA tone in the MRN leads to induction or suppression of hippocampal theta rhythm. We found that MRN application of the GABA(A) agonist muscimol (0.05-1.0 mM) or GABA(B) agonist baclofen (0.2 mM) by reverse microdialysis had strong theta promoting effects. The GABA(A) antagonist bicuculline infused in low concentrations (0.1, 0.2 mM) eliminated theta rhythm. A short period of theta activity of higher than normal frequency preceded hippocampal desynchronization in 46% of rats. Bicuculline in larger concentrations (0.5, 1.0, 2.0 mM) resulted in a biphasic response of an initial short (<10 min) hippocampal desynchronization followed by stable theta rhythm that lasted as long as the infusion continued. The frequency and amplitude of theta waves were higher than in control recordings and the oscillations showed a conspicuous intermittent character. Hippocampal theta rhythm elicited by MRN administration of bicuculline could be completely (0.5 mM bicuculline) or partially (1.0 mM bicuculline) blocked by simultaneous infusion of the GABA(B) antagonist CGP35348. Our findings suggest that the GABAergic network may have two opposing functions in the MRN: relieving the theta-generators from serotonergic inhibition and regulating the activity of a theta-promoting circuitry by the fluctuating GABA tone. The two mechanisms may be involved in different functions. 相似文献
7.
Genetic variants of homocysteine metabolizing enzymes and the risk of coronary artery disease 总被引:2,自引:0,他引:2
Janosíková B Pavlíková M Kocmanová D Vítová A Veselá K Krupková L Kahleová R Krijt J Kraml P Hyánek J Zvárová J Andel M Kozich V 《Molecular genetics and metabolism》2003,79(3):167-175
It is unresolved whether elevated homocysteine in coronary artery disease (CAD) is the cause of arteriosclerosis or its consequence. In contrast, genetic variants of enzymes that metabolize homocysteine cannot be altered by arteriosclerosis. Consequently, their association with CAD would permit to imply causality. We modeled by regression analysis the effect of 11 variants in the methionine cycle upon CAD manifestation in 591 controls and 278 CAD patients. Among the examined variants only the carriership for the c.844ins68 in the cystathionine beta-synthase (CBS) gene was associated with a significantly lowered risk of CAD (OR=0.56; 95% CI=0.35-0.90 in the univariable, and OR=0.41, 95% CI=0.19-0.89 for obese people in the multivariable analysis, respectively). Healthy carriers of the c.844ins68 variant exhibited, compared to the wild type controls, significantly higher postload ratios of blood S-adenosylmethionine to S-adenosylhomocysteine (61.4 vs. 54.9, p=0.001) and of plasma total cysteine to homocysteine (8.6 vs. 7.3, p=0.004). The changes in these metabolites are compatible with an improved methylation status and with enhanced activity of homocysteine transsulfuration. In conclusion, the coincidence of clinical and biochemical effects of a common c.844ins68 CBS variant supports the hypothesis that compounds relating to homocysteine metabolism may play role in the development and/or progression of CAD. 相似文献
8.
Dr. med. Heinrich Viktor Klein 《Virchows Archiv : an international journal of pathology》1927,266(2):357-392
Ohne ZusammenfassungMit 15 Textabbildungen.Das Bedürfnis nach Stützung schwächerer Gedanken durch stärkere wird auchKausalitäts bedürfnis genannt und ist die Haupttriebfeder aller naturwissenschaftlichenErklärungen. Ernst Mach.Nach einem auf der 89. Versammlung deutscher Naturforscher und Ärzte in Düsseldorf im September 1926 gehaltenen Vortrage. Vgl. auch Fortschritte d. naturwissenschaftl. Forschung, herausgeg. vonE. Abderhalden, Bd. XII, H. 4. 相似文献
9.
Tong Chen Hao Bai Ying Shao Melanie Arzigian Viktor Janzen Eyal Attar Yi Xie David T Scadden Zack Z Wang 《Stem cells (Dayton, Ohio)》2007,25(2):392-401
The molecular mechanisms that regulate human blood vessel formation during early development are largely unknown. Here we used human ESCs (hESCs) as an in vitro model to explore early human vasculogenesis. We demonstrated that stromal cell-derived factor-1 (SDF-1) and CXCR4 were expressed concurrently with hESC-derived embryonic endothelial differentiation. Human ESC-derived embryonic endothelial cells underwent dose-dependent chemotaxis to SDF-1, which enhanced vascular network formation in Matrigel. Blocking of CXCR4 signaling abolished capillary-like structures induced by SDF-1. Inhibition of the SDF-1/CXCR4 signaling pathway by AMD3100, a CXCR4 antagonist, disrupted the endothelial sprouting outgrowth from human embryoid bodies, suggesting that the SDF-1/CXCR4 axis plays a critical role in regulating initial vessel formation, and may function as a morphogen during human embryonic vascular development. 相似文献
10.
Pneumococcal serotype 19F conjugate vaccine induces cross-protective immunity to serotype 19A in a murine pneumococcal pneumonia model
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Jakobsen H Sigurdsson VD Sigurdardottir S Schulz D Jonsdottir I 《Infection and immunity》2003,71(5):2956-2959
Immunization with a pneumococcal conjugate vaccine (PNC) containing serotype 19F induces cross-reactive antibodies to 19A in mice and human infants. Active immunization with PNC and passive immunization with serum samples from infants vaccinated with PNC containing serotype 19F, but not serotype 19A, protected against lung infection caused by both serotypes in a murine model. 相似文献