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81.
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   
82.
Sir, Metformin has been used for many decades as an effective glucose-loweringmedication in the treatment of type 2 diabetes mellitus. Recentstudies clearly demonstrated that metformin reduced secondarycomplications of diabetes mellitus type 2 without promotingweight gain, which is in contrast to treatment with insulinand/or sulphonylurea [1]. Lactic acidosis is a serious sideeffect observed with metformin treatment and  相似文献   
83.
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   
84.
Clinical efficacy, safety and pharmacokinetic properties of the high-purity double-virus inactivated plasma-derived factor VIII concentrate Haemoctin SDH (pdFVIII) were evaluated in three prospective open-label uncontrolled studies in previously treated patients (PTPs) with severe haemophilia A. The pharmacokinetic properties assessed at baseline and after 3 months of treatment are in accurate accordance with published data and remain unchanged over time (study A, n = 12). Mean terminal elimination half-life was 11.8 and 11.9 h, mean incremental recovery (IU dL(-1)/IU kg(-1)) was 2.3 and 2.0, respectively. Long-term efficacy and safety, in particular the potential immunogenicity, were investigated in a total of 53 PTPs (studies A and B) treated prophylactically and on-demand, as required. PdFVIII has shown to be effective in preventing and controlling bleeding episodes; 23.5% of patients were free of bleeding events. A total of 177 haemorrhages occurred with 74.0% resolving after a single infusion, 87.6% within two infusions. 98.3% of responses reported on haemorrhages were rated as 'excellent' or 'good'. Moreover, 'excellent' haemostatic efficacy has been demonstrated in 10 surgical procedures including general and severe orthopaedic interventions (study C). No complication occurred in any surgery. Few adverse events were reported, one patient developed a high-titre FVIII inhibitor without clinical relevance. In all three studies, over 6 million units were administered in nearly 4300 infusions, approximately 94% units or infusions were given for prophylaxis and only 6% for treatment on-demand. In conclusion, pdFVIII has shown to be effective, safe and well tolerated in long-term prophylaxis and treatment on-demand as well as after minor and major surgical procedures.  相似文献   
85.
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   
86.
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   
87.
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   
88.
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   
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