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51.
The objective of the present study was to assess possible adaptive functional changes in the masticatory system after insertion of fixed prostheses supported by osseointegrated implants in the edentulous mandible. Registrations of mandibular movement characteristics and maximal biteforce were performed at insertion and after 1 week, 3 months and 1 year after connection. The duration of the opening and closing phase decreased and maximal biteforce increased significantly (p < or = 0.05-0.001) from connection of the prostheses to the annual check-up. However, the process of functional adaptation implied 2 identified stages. An immediate phase that occurred within the 1st week, probably due to altered impact from mechano-sensitive receptors and a later more time-dependent phase, based on learning and new cortical engrams. Accordingly, the process of adaptation will continue over a long period of time. 相似文献
52.
Two cases are reported in which, after ACL reconstruction with autologous hamstring grafts, tibial polylactide interference
screws migrated into the knee joint. Clinically, both patients presented with recurrent locking of the joint. In one case,
a broken 15 mm-long tip of the screw was found intra-articularly. In the other case, the whole screw had migrated into the
joint cavity. The degradation process of polylactic acid, operative technique and bone quality are discussed as possible reasons
for these complications. 相似文献
53.
目的 :观察不同部位静脉注射对无痛人工流产术的影响。方法 :随机将 2 0 0例要求行无痛人工流产术的患者分成二组 ,一组静脉注射部位为手背静脉组 ,另一组静脉注射部位为肘部浅静脉 (贵要静脉或肘正中静脉 )组 ,观察静脉推注异丙酚时患者的注射部位有无疼痛症状。结果 :肘部浅静脉注射部位疼痛感明显轻于手背静脉 ,肘部浅静脉注射部位的麻醉起效时间快于手背静脉 ,两组差异有显著性 (P <0 0 5 )。结论 :选择肘部浅静脉注射异丙酚可减轻患者注射部位的疼痛 ,可在短时间内取得理想的麻醉效果。 相似文献
54.
Louise Rose MN Adult Ed Cert BN ICU Cert Dip Nurs Marie F. Gerdtz RN BN AE Cert GDAET PhD 《Australasian emergency nursing journal : AENJ》2007,10(1):26-29
The use of mechanical ventilation in the Emergency Department requires adequate resources in order to maintain patient safety and avoid potential risks. Moreover, developments in technology require increased knowledge of mechanical ventilation techniques to address the complexity of decision-making involved. Organisational issues and system factors have the potential to negatively impact on the ability of the emergency service to provide optimum care to patients receiving mechanical ventilation. These issues include staffing and skill-mix, demand on emergency services, role-delineation, scope of practice, and current mechanisms for monitoring of quality and safety. Furthermore, in response to advances in ventilator technology, current education programs for both nursing and medical staff require review to ensure that they provide comprehensive information about the types of ventilation techniques now available and the relative risks and benefits associated with their application.This article is the second in a two-part series and explores the educational and organisational factors that impact upon safety and quality of care delivered to patients receiving mechanical ventilation in the emergency department. Recommendations for future policy development, curriculum review and reporting mechanisms to support further research in the application of mechanical ventilation in the emergency department are made. 相似文献
55.
骨水泥型人工股骨头假体治疗高龄股骨颈骨折 总被引:5,自引:1,他引:4
目的报告骨水泥型人工股骨头假体治疗高龄股骨颈骨折的疗效。方法131例患者(新鲜骨折101例,陈旧性骨折30例按Garden分型:Ⅱ型23例,Ⅲ型62例,Ⅳ型46例),取后外侧切口安置骨水泥型人工股骨头,术后药物预防静脉血栓。结果随访0.5~8年,优良率96.4%。结论骨水泥型人工股骨头假体置换术具有手术简单,术后恢复快等优点,适用于高龄股骨颈骨折患者。 相似文献
56.
Cora Rotary Pump for Implantable Left Ventricular Assist Device: Biomaterial Aspects 总被引:3,自引:0,他引:3
Abstract: Our group is developing a left ventricular assist device based on the principle of the Maillard-Wankel rotative compressor: it is a rotary, not centrifugal, pump that produces a pulsatile flow. Stringent requirements have been defined for construction materials. They must be light, yet sufficiently hard and rigid, and able to be machined with high precision. The friction coefficient must be low and the wear resistance high. The materials must be chemically inert and not deformable. Also, the materials must be biocompatible, and the blood contacting surface must be hemocompatible. We assessed the materials in terms of physiochemistry, mechanics, and tribology to select the best for hemocompatibility (determined by studies of protein adsorption: platelet, leukocyte, and red cell retention: and hemolysis, among other measurements) and biocompatibility (determined by measurement of complement activation and toxicity, among other criteria). Of the materials tested, for short- and middle-term assistance, we chose titanium alloy (Ti6 AI4 V) and alumina ceramic (Al2 O3 ) and for long-term and permanent use, composite materials (TiN coating on graphite). We saw that the polishing process of the substrate must be improved. For the future, the best coating material would be diamond-like carbon (DLC) or crystalline diamond coating. 相似文献
57.
J. P. Clarke 《Intensive care medicine》1997,23(1):106-109
Objective: To determine the effects of pressure control inverse ratio ventilation [PC-IRV], as compared with volume controlled normal
ratio ventilation [VC], on the intracranial pressure [ICP] of patients with severe head injury.
Design: A prospective study with unblinded intervention.
Setting: The Intensive Therapy Unit of a base hospital.
Patients and participants: Nine cases of head injury requiring mechanical ventilation and intracranial pressure monitoring were studied.
Interventions: Patients were twice transferred from VC (I:E ratio 1:2) to PC-IRV (I:E ratio 2:1). Firstly, tidal volume was maintained
at an equal value. Secondly, end tidal CO2 was maintained at an equal value. No other changes were made to ventilation, vasopressor therapy or ICP control.
Measurements and results: Measurements were taken of ICP, mean arterial pressure (MAP) end tidal CO2 and respiratory parameters. In the first observation, there were significant changes in peak inspiratory pressure (PIP),
mean airway pressure (Paw) and intrinsic positive end expiratory pressure (PEEP) but not for ICP, end tidal CO2, MAP and cerebral perfusion pressure (CPP). The correlation between change in ICP and change in end tidal CO2 was r=–0.74. In the second observation there were significant changes in tidal volume, PIP, Paw and intrinsic PEEP but not for
ICP, MAP and CPP. The correlation between the change in ICP and the change in Paw was insignificant.
Conclusions: PC-IRV has a minimal net effect on ICP. Changes in ICP correlate more strongly with changes in CO2 than changes in Paw.
Received: 16 January 1996 Accepted: 2 September 1996 相似文献
58.
F. BRUNET J. P. MIRA C. CERF M. BELGHITH O. SOUBRANE J. L. TERMIGNON† B. RENAUD L. FIEROBE I. HAMY M. MONCHI E. DESLANDE A. BRUSSET† J. F. DHAINAUT 《Artificial organs》1994,18(11):826-832
Abstract: This open clinical study was aimed at testing the hypothesis that an intravascular oxygenator (IVOX) may help to perform permissive hypoventilation in 10 patients with severe ARDS. After initial evaluation, we tried to reduce ventilator settings before and after IVOX implantation. Before IVOX, poor clinical tolerance and worsening oxygenation did not allow for a significant decrease in ventilator settings. With IVOX, peak inspiratory pressure (PIP) was reduced from 47 to 39 cm H2 O (p = 0. 005) and minute ventilation from 13 ± 3. 5 to 11 ± 3 L/min. CO2 removal by IVOX allowed a significant decrease in Paco2 from 66 ± 15 to 59 ± 13 mm Hg. Improvement of oxygenation with IVOX was not signify cant. Furthermore, interruption of oxygen flow through IVOX did not change oxygenation variables. Tolerance of the IVOX device was good, but insertion of the device was followed by a significant decrease in both cardiac index and pulmonary wedge pressure. In conclusion, IVOX improves tolerance of hypoventilation by limiting hypercapnia in ARDS patients. These preliminary results must be confirmed by a randomized controlled study 相似文献
59.
本文报道了应用细胞培养方法研究炭素纤维人工食管材料对细胞的毒性作用。实验结果表明,该材料对于体外培养细胞的形态、细胞的增殖等方面均无不良影响及毒性作用,从而为炭素纤维人工食管材料的应用提供了细胞学根据。 相似文献
60.
Wong Merng Koon 《中华创伤骨科杂志》2006,8(10):944-948
Objective Intra-articular fractures of the distal radius in young adults comprise a distinet fracture pattern that is diffficuh to manage and associated with a high frequency of post-traumatic arthritis.Restoration of articular congruency and alignment should improve the outcome.Methods In this study we prospectively re- viewed the results of 21 consecutive cases of dorsally displaced intra-articular distal radius fractures which were treated with internal fixation after failing to achieve articular congruency with closed reduction.Results 3 patients were lost to follow-up.For the rest of 18 patients,follow-up time ranges from 18 to 75 weeks the fractures had healed with highly satisfactory radiographic and functional results.The final volar tilt averaged 4.9°;radial inclination 23.9°;radial length 14mm;and articular incongruity,0.1 mm.Wrist motion at final follow-up examination aver- aged flexion 62°,extension 60°,radial deviation 16°,ulnar deviation 27°,pronation 77°and supination 74°.Grip strength averaged 83% of the uninjured side.The overall outcome of 18 patients(94.4%)had a good or excellent result according to the system of Gartland and Werley and 18 patients(72.2%)had a good result according to the modified system of Green and O'Brien at the most recent evaluation.The only complication in this series was a superficial pin tract infection,which was rapidly resolved with removal of pins at 5th week of external fixation. Conclusion Thus restoration of articular congruency and alignment is possible with minimal complication using modern non-angular stable methods of internal fixation. 相似文献