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131.
Steinfeldt F Seifert W Günther KP 《Zeitschrift für Orthop?die und ihre Grenzgebiete》2003,141(3):357-361
AIM: Evaluation of practicability and functional benefit with modern carbon fibre knee ankle foot orthoses in polio patients. METHODS: In a retrospective analysis, fifty-five (55) polio patients between the ages of 42 and 80 years who had been provided with a carbon fibre orthoses for a minimum of three months, were asked about their acceptance as well as changes in functional capacity and comfort. RESULTS: Clear improvements were shown in walking, sitting and automobile driving as well as comfort and dressing/undressing of the orthoses. Through the use of these new orthoses, the maximum walking distance increased significantly--at least partially due to less weight (40%). 95% of all treated patients were very satisfied or satisfied. CONCLUSION: The use of carbon fibre material in the orthotic treatment of polio patients seems to be supported by the positive results of our study. 相似文献
132.
OBJECTIVE: The Spiegelberg 3-PN intraparenchymal pressure sensor was clinically evaluated. DESCRIPTION OF INSTRUMENTATION: The Spiegelberg intraparenchymal pressure sensor is a low-cost device that uniquely performs regular automatic zeroing in situ throughout the measurement period. OPERATIVE TECHNIQUE: The Spiegelberg sensor was inserted in 87 patients who required intracranial pressure monitoring as part of their routine management. Complications were assessed by postoperative computed tomographic scanning and clinical investigation. The automated zeroing procedure was assessed after implantation of the sensor and during long-term measurement. In five patients, the "gold standard' of intraventricular pressure was measured simultaneously and compared with the intraparenchymal or subdural Spiegelberg 3-PN pressure. EXPERIENCE AND RESULTS: No complications associated with the Spiegelberg sensor were observed. The duration of monitoring ranged from 3 to 28 days (mean, 10 d). In 3 patients, technical problems occurred, and in 84 patients, the pressure measurement was successful, including the automatic zeroing procedures performed by the monitor after insertion and hourly thereafter. The absolute difference between the Spiegelberg reading and the intraventricular pressure was less than +/-3 mm Hg in 99.6% and less than +/-2 mm Hg in 91.3% of readings. An Altman-Bland bias plot revealed good agreement between the two methods, with an average bias of 0.5 mm Hg, but revealed a significant trend toward 10% lower Spiegelberg readings with increasing intracranial pressure of >25 mm Hg. There was no difference between intraparenchymal and subdural locations. CONCLUSION: The Spiegelberg 3-PN sensor was reliable and simple to use. It can be recommended for routine intraparenchymal and subdural pressure measurement at a considerably lower price compared with other tip transducers and has the unique advantage of automated zeroing in vivo. 相似文献
133.
Topographical analysis of the structural,biochemical and dynamic biomechanical properties of cartilage in an ovine model of osteoarthritis 总被引:7,自引:0,他引:7
Appleyard RC Burkhardt D Ghosh P Read R Cake M Swain MV Murrell GA 《Osteoarthritis and cartilage / OARS, Osteoarthritis Research Society》2003,11(1):65-77
OBJECTIVE: The relationship between the topographical variations in the structural, biochemical and dynamic biomechanical properties of articular cartilage (AC) before and 6 months after meniscectomy has not been previously reported but is clearly relevant to our understanding of the role of mechanical factors on the pathogenesis of osteoarthritis (OA). The objective of this study was to address this deficiency using an ovine model of OA induced by bilateral lateral meniscectomy. DESIGN: The dynamic effective shear modulus (G*) and phase lag were determined ex vivo at 26 individual locations over the medial and lateral tibial plateaux of non-operated and meniscectomized ovine joints 6 months after surgery using a novel hand-held dynamic indentation probe. AC thickness was measured with a needle penetration probe. The AC from the same topographical locations as indented was then analysed for sulfated glycosaminoglycans (S-GAG) as a measure of proteoglycan (PG) levels, collagen and water content. Histological evaluation of the collagen organization using quantitative analysis of birefringence intensity was performed on stained tissue sections from the same topographical locations of each animal. RESULTS: It was demonstrated that the AC of the entire lateral tibial compartment of the meniscectomized joints underwent significant local degenerative and compensatory changes as indicated by a decreased G* and an increase in phase lag and water content. This was accompanied by a decrease in PG content of the AC of the middle and inner regions. While the AC of the outer region of the lateral meniscectomized compartment showed a marked increase in PG content and a more than two-fold increase in thickness, these tissues were also found to be structurally inferior, as indicated by a decreased G* and abnormal collagen birefringence intensity. The AC thickness was elevated at all locations of the lateral and medial tibial plateau of the meniscectomized joints. Strong and significant correlations between the biomechanical and biochemical data were established for a number of the parameters examined, especially between collagen content and G*, collagen content and AC thickness, and G* and AC thickness. An inverse correlation between S-GAG content and G* was only apparent in non-operated control tissues, whereas correlations between collagen and water content, water content and G*, and water content and thickness were evident for AC of the meniscectomized tibial plateaux. Less striking changes were noted in the medial compartment where the intact meniscus remained in place. However, elevated PG content, thicker AC together with slight changes in G* suggested an early hypertrophic response in these tissues. CONCLUSION: This study has highlighted the variable response of AC in different topographical regions of meniscectomized joints to the altered mechanical stresses introduced by this surgical procedure. The AC at the joint margins, while thicker and richer in PG, was found to be biomechanically softer (lower shear modulus) than normal AC, and because of this, would be expected to undergo degenerative changes with time leading to the onset of OA. 相似文献
134.
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136.
Bhargava M Marrouche NF Martin DO Schweikert RA Saliba W Saad EB Bash D Williams-Andrews M Rossillo A Erciyes D Khaykin Y Burkhardt JD Joseph G Tchou PJ Natale A 《Journal of cardiovascular electrophysiology》2004,15(1):8-13
INTRODUCTION: A retrospective analysis was performed to define the impact of age on the outcomes and complications in patients undergoing pulmonary vein isolation (PVI). PVI is an evolving technique for the management of atrial fibrillation (AF). The impact of age on the risks, outcomes, and complications of PVI has not been well defined. METHODS AND RESULTS: A total of 323 patients (259 men and 64 women; age 18-79 years) underwent PVI for treatment of drug-refractory symptomatic AF. An ostial isolation of the pulmonary veins was done using a cooled-tip ablation catheter guided by circular mapping. The patients were divided into three groups based on age (group I: <50 years, group II: 51-60 years, group III: >60 years) and the results were compared. There were 106 patients in group I, 114 patients in group II, and 103 patients in group III (mean age 41.3 +/- 7.8 years, 55.4 +/- 2.75 years, and 66.6 +/- 4.18 years, respectively) who underwent PVI for paroxysmal (53.8%), persistent (10.8%), or permanent (35.3%) AF. Baseline characteristics were similar except for a higher prevalence of hypertension and/or structural heart disease in groups II and III (58% and 63% vs 33% in group I, respectively). The procedural variables were similar in all age groups. The overall risk of complications was similar in the three groups, except that the risk of stroke was significantly higher in patients >60 years of age (3% vs 0%; P < 0.05). The recurrence rates of AF were similar in the three age groups (15.1%, 16.7%, and 18.4%, respectively; P > 0.05). The risk of severe pulmonary vein stenosis (1.8%, 2.6%, and 0.9%, respectively) was low and did not vary with age. CONCLUSION: PVI is a safe and effective treatment for patients with drug-refractory symptomatic AF, and its benefits extend to all age groups. The risk of procedural complications, especially thromboembolic events, appears to be higher in the elderly age group. This observation needs to be considered while assessing potential candidates for the procedure. 相似文献
137.
Meyer-Hoffert U Rogalski C Seifert S Schmeling G Wingertszahn J Proksch E Wiedow O 《Experimental dermatology》2004,13(4):234-241
Human keratinocytes are known to express the protease-activated receptors, PAR-1 and PAR-2. Activation of PAR-1 results in increased proliferation, whereas PAR-2 activation results in decreased keratinocyte proliferation. Trypsin activates PAR-1 and in higher concentrations, PAR-2. The aim of this study was to evaluate the overall effect of trypsin on keratinocyte proliferation in a mouse in vivo and in vitro model. Daily topical application of 0.3-300 pmol trypsin/cm2 on hairless mouse skin induced dose-dependent epidermal hyperproliferation as determined by an increase in 5-bromo-2'-deoxyuridine incorporation of up to eight-fold in basal keratinocytes and an up to three-fold increase in keratinocyte layers. This was accompanied by an increased transepidermal water loss. These effects of trypsin were abolished by the addition of the trypsin inhibitor n-p-tosyl-l-lysine-chloromethyl ketone. Histological analysis revealed acanthosis, hypergranulosis, and spongiosis in the epidermis as well as vasodilatation and an inflammatory infiltrate in the upper dermis. In the murine keratinocyte cell line PAM-212 activation of PAR-1 with specific activating peptides resulted in a calcium influx and an increase of proliferation, whereas activation of PAR-2 caused a diminished proliferation. Incubation with trypsin, PAR-1-, and PAR-2-activating peptides induced cytokine-induced neutrophil chemoattractant (KC) mRNA expression as a marker for inflammation in PAM-212 in a dose-dependent manner. In conclusion, our results suggest that trypsin induces in vivo epidermal proliferation and inflammation. Proliferation seems not to be signaled by PAR activation, but PAR-2-induced KC chemokine expression may contribute in part to trypsin-induced inflammation. 相似文献
138.
Intrapulmonary administration of perfluorochemicals (PFC) has been suggested for reasons other than respiratory insufficiency. PFC application has been described to affect cerebral Hb concentration, however, data for healthy lungs are missing. Newborn piglets were randomized into 3 groups (30-ml slow-filling, 10-ml slow-filling and 30-ml rapid-filling), orally intubated and mechanically ventilated. Partial liquid ventilation (PLV) was initiated by filling the lung with PF5080 (10 or 30 ml/kg) at a rate of 1.5 ml/min (slow filling) or within 45 s (rapid filling). Vital signs, blood gases, tidal volume (VT) and changes in the cerebral concentration of oxygenated hemoglobin (HbO(2)) and total Hb were determined for up to 20 min. Rapid administration of PFC caused an immediate drop in HbO(2), PaO(2) and VT. The concentration of oxygenated and total Hb increased thereafter and remained high. We found a slow increase in PaCO(2), HbO(2) and total Hb in the 30-ml slow-filling group, but almost no changes in the 10-ml slow filling group (except for a decrease in PaO(2)). According to our data, PLV with 10 ml/kg should be preferred since cerebral alterations are minimal. If complete filling of the lung is needed PFC should be administered slowly to minimize side effects. 相似文献
139.
David A Erickson Stacy Hollfelder Justin Tenge Mark Gohdes Jeffrey J Burkhardt Philip A Krieter 《Drug metabolism and disposition》2007,35(12):2232-2241
The in vitro metabolism of [(14)C]bicifadine by hepatic microsomes and hepatocytes from mouse, rat, monkey, and human was compared using radiometric high-performance liquid chromatography and liquid chromatography/tandem mass spectrometry. Two main metabolic pathways were identified in all four species. One pathway was an NADPH-dependent pathway in which the methyl group was oxidized to form a hydroxymethyl metabolite (M2). Its formation was inhibited in human microsomes only by quinidine, a CYP2D6 inhibitor. In incubations with individual cDNA-expressed human cytochromes P450, M2 was formed only by CYP2D6 and CYP1A2, with CYP2D6 activity 6-fold greater than that of CYP1A2. M2 was oxidized further to the carboxylic acid metabolite (M3) by hepatocytes from all four species. The second major metabolic pathway was an NADPH-independent oxidation at the C2 position of the pyrrolidine ring, forming a lactam metabolite (M12). This reaction was almost completely inhibited in human hepatic microsomes and mitochondria by the monoamine oxidase (MAO)-B-specific inhibitor selegiline. Clorgyline, a specific inhibitor of MAO-A, was less effective in inhibiting M12 formation. Other metabolic pathways of variable significance among the four species included the formation of carbamoyl-O-glucuronide, hydroxymethyl lactam, and carboxyl lactam. Overall, the data indicate that the primary enzymes responsible for the primary metabolism of bicifadine in humans are MAO-B and CYP2D6. 相似文献
140.