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排序方式: 共有10000条查询结果,搜索用时 234 毫秒
41.
Birgit Herting MD Bettina Beuthien‐Baumann MD Katrin Pöttrich PhD Markus Donix MD Antje Triemer PhD Johannes B. Lampe MD Rüdiger von Kummer MD Karl Herholz MD Heinz Reichmann MD Vjera A. Holthoff MD 《Movement disorders》2007,22(4):490-497
Depressive symptoms are common in patients with neurodegenerative disorders. Imaging studies suggest that a disruption of frontal-subcortical pathways may underlie depression associated with basal ganglia disease. This pilot study tested the hypothesis that frontal dysfunction contributes to depression associated with multiple system atrophy (MSA) and progressive supranuclear palsy (PSP). Depressed patients with MSA (n = 11), PSP (n = 9), and age-matched controls (n = 25) underwent measures of cerebral glucose metabolism applying positron emission tomography with (18)F-fluorodeoxyglucose. Regional metabolism in the patient groups was compared to the normal subjects using the voxel-based statistical parametric mapping. Depressive symptom severity (Hamilton Depression Rating) and degree of locomotor disability (Hoehn & Yahr) were assessed in the patient groups. The association between prefrontal metabolism and the occurrence of depressive symptoms and the degree of locomotor disability was investigated. When compared to controls, MSA patients revealed significant metabolic decreases in bilateral frontal, parietal, and cerebellar cortex and in the left putamen. In PSP patients, significant hypometabolism was demonstrated in bilateral frontal cortex, right thalamus, and midbrain. Depression severity but not the patients' functional condition was significantly associated with dorsolateral prefrontal glucose metabolism in both patient groups. The findings of this pilot study support the hypothesis that depressive symptoms in MSA and PSP are associated with prefrontal dysfunction. 相似文献
42.
In patients with renal failure, the high prevalence of vascular,valvular and soft-tissue calcifications and their consequencesfor cardiovascular outcomes have recently received much attention.Several studies documented that the calcification burden isassociated with increased morbidity and mortality in uraemia.In vitro and in vivo research has demonstrated that tissue calcificationis not just based on passive calcium and phosphate precipitation,but that active cellular processes such as osteogenic differentiationof vascular smooth muscle cells (VSMC) are involved and thata number of local and systemic calcium-regulatory factors controland prevent unwanted extra-osseous calcification. An importantfinding was the new understanding that calcium and phosphateare immediate inducers of osteogenic 相似文献
43.
Increased response of renal perfusion to the antioxidant vitamin C in type 2 diabetes. 总被引:2,自引:0,他引:2
Christian Delles Markus P Schneider Sebastian Oehmer Ingrid Fleischmann Erwin F Fleischmann Roland E Schmieder 《Nephrology, dialysis, transplantation》2004,19(10):2513-2518
BACKGROUND: Reactive oxygen species play a major role in the development of endothelial dysfunction. It is as yet unspecified whether increased oxidative stress contributes to endothelial dysfunction of the renal vasculature in patients with type 2 diabetes. METHODS: Renal haemodynamics were studied in 20 patients with type 2 diabetes and arterial hypertension (age 62 +/- 5 years) and 20 non-diabetic hypertensive patients at baseline and following infusions of the nitric oxide synthase inhibitor, N(G)-monomethyl-L-arginine (L-NMMA; 4.25 mg/kg); the substrate of nitric oxide synthase, L-arginine (100 mg/kg); and the antioxidant, vitamin C (3 g, co-infused with L-arginine 100 mg/kg). RESULTS: The response of renal plasma flow (RPF) to L-NMMA (-54 +/- 62 and -45 +/- 42 ml/min/1.73 m(2); P = NS) and L-arginine (+46 +/- 36 and +49 +/- 25 ml/min/1.73 m(2); P = NS) was not different between diabetic and non-diabetic patients. In contrast, vitamin C induced a more pronounced increase in RPF in diabetic than in non-diabetic patients when co-infused with L-arginine (+71+/-47 and +43+/-33 ml/min/1.73 m(2); P<0.05). CONCLUSIONS: The difference in the response of renal perfusion to an antioxidant suggests increased formation of reactive oxygen species and thereby reduced nitric oxide bioavailability in the renal vasculature of patients with type 2 diabetes. 相似文献
44.
Heather G Stewart Peter M Andersen Andrew Eisen Markus Weber 《Clinical neurophysiology》2006,117(8):1850-1861
OBJECTIVE: To examine corticomotoneuronal function in amyotrophic lateral sclerosis (ALS) patients carrying superoxide dismutase 1 (SOD1) mutations using peristimulus time histograms (PSTH). METHODS: Six I113T, 3 A4V, one G41D and one G114A patient were studied along with 21 healthy control subjects. Analyses included comparison with previously reported data from 8 D90A homozygous and 12 sporadic ALS (SALS) patients examined by the authors using identical methodology. RESULTS: Cortical threshold was significantly reduced in A4V patients (41.3%) compared to I113T (58%), SALS (57%) and D90A (71%) patients, as well as healthy controls (49.7%). Estimated excitatory postsynaptic potentials (EPSPs) were significantly larger in A4V patients (4.39 mV) compared to healthy controls (2.95 mV), I113T (2.71 mV) and SALS (2.39 mV) patients. Clinical features and PSTH parameters in I113T were similar to SALS, however, PSTH primary peaks (PP) were significantly more dispersed, 9.5 ms compared to 4ms in SALS. PSTHs from single G41D and G114A patients were unremarkable, apart from large EPSP amplitudes in the G114A patient. CONCLUSIONS: ALS patients with A4V and I113T SOD1 mutations have distinctive corticomotoneuronal changes that are different from those in D90A homozygous and SALS patients. SIGNIFICANCE: PSTH studies should be considered for future in vivo studies of SOD1 pathophysiology in ALS. 相似文献
45.
Alexander Dullenkopf Goran Lamesic Andreas Gerber Markus Weiss 《Journal canadien d'anesthésie》2003,50(5):507-510
PURPOSE: A simple technical solution is presented to provide video transmission from the tip of a Bullard laryngoscope to a bedside video display, while the operator is still able to look through the viewing ocular of the Bullard laryngoscope during tracheal intubation. EQUIPMENT: This is achieved by insertion of an ultrathin fibreoptic video-endoscopic system into the working channel of the Bullard laryngoscope. Thereby the view from the distal blade tip is transmitted to a bedside monitor, without interfering with the use of the Bullards laryngoscope's original eyepiece. The presented technical solution allows video transmission without considerable additional weight normally associated with attaching video endoscopy cameras, light and camera cables to endoscopic devices. Thus, the Bullard laryngoscope remains lightweight and easy to maneuver. A screw-threaded adapter with a side-port is proposed to prevent displacement of the fibreoptic cable while still allowing application of oxygen. CONCLUSION: Experience and skills with tracheal intubation using the presented video-enhanced Bullard laryngoscope can be achieved in the originally intended way, while the supervisor or attending viewers can follow the tracheal intubation procedure on the video display. 相似文献
46.
Comparison of three different purification methods for the routine preparation of [11C] Metomidate. 总被引:1,自引:0,他引:1
Markus Mitterhauser Wolfgang Wadsak Oliver Langer Joern Schmaljohann Georg Zettinig Robert Dudczak Helmut Viernstein Kurt Kletter 《Applied radiation and isotopes》2003,59(2-3):125-128
PET with (R)-[O-methyl-11C] metomidate ([11C] MTO) is an attractive method for the characterisation of adrenal masses discriminating lesions of adrenal cortical origin from noncortical lesions. [11C] MTO was prepared by the reaction of [11C] methyliodide with the corresponding free acid. Three purification methods have been compared. The method of choice uses preparative HPLC with a ready-to-use weak acidic solvent. 相似文献
47.
Braunschweig Rainer Biesold Markus Beilicke Matthias Marintschev Ivan 《Trauma und Berufskrankheit》2002,4(1):S68-S73
Trauma und Berufskrankheit - Zusammenfassung Der Nachweis oder Ausschluss ossärer Verletzungen am Ellbogengelenk wird primär mit der Projektionsradiographie in 2 Ebenen geführt.... 相似文献
48.
Photocarcinogenesis and inhibition of intercellular adhesion molecule 1 expression in cells of DNA-repair-defective individuals 下载免费PDF全文
49.
Amir Kurtaran Josef Pfreitfellner Peter Schaffarich Peter Smith-Jones Bruno Niederle Markus Raderer Irene Virgolini Helmar Bergmann Ernst Havlik 《European journal of nuclear medicine and molecular imaging》1997,24(10):1298-1300
The purpose of this study was to estimate the radiation doses to nursing staff, other patients, accompanying persons and family
members deriving from patients undergoing 111In-DTPA-d-Phe-1-octreotide (111In-OCT) scintigraphy. Dose rates were measured from 16 patients who had received an intravenous injection of 140±40 MBq 111In-OCT. The measurements were performed at three different distances (0.5, 1 and 2 m) at 10–20 min, 5–7 h and 24 h (and in
some cases, up to 48 h) after administration of 111In-OCT. The effective half-lives of the biexponential decrease of the dose rates were estimated to be 2.94±0.27 h (T
1) and 65.17±0.58 h (T
2). The calculated maximum dose to other persons in the waiting area was 27.2 μSv, to family members 61.5 μSv, to nursing staff
in a ward 24.1 μSv and to neighbouring patients in the ward 69.5 μSv. Our results clearly demonstrate that the calculated
maximum radiation exposure to accompanying persons, personnel, family members and other patients is well below the maximum
annual dose limit for non-professionally exposed persons.
Received 20 May and in revised form 9 July 1997 相似文献
50.
Markus Friedrich Wolfram Sterry Khusru Asadullah 《Journal der Deutschen Dermatologischen Gesellschaft》2003,1(1):12-21
The current standard systemic therapeutic modalities for psoriasis have many potential side effects. Progress made in the understanding of the pathophysiology of psoriasis as a T‐cell‐mediated dermatosis provide options for new more precise therapeutic approaches. These immunological therapeutic strategies involve the inhibition/depletion of activated T‐lymphocytes, the inhibition of antigen presentation and thus the regulation of T‐cell activation, the inhibition of adhesion of inflammatory cells, the inhibition of effects of proinflammatory mediators and the administration of antiinflammatory cytokines. This article summarizes these new systemic therapeutic approaches. Clinical results in the early studies have been mixed. In the next years further results of phase II‐ and phase III‐studies may be expected, which should allow better assessment of the potential of those particular approaches. Some of these approaches could lead to the approval of new drugs to treat psoriasis and to enhance or replace already existing therapeutic options. Furthermore results of therapeutic experiments should contribute to a better understanding of the disease. As we learn which mechanisms are more or less important for the disease, we will be better able to plan intervention strategies. 相似文献