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51.
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
52.
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
53.
一氧化氮在氯胺酮麻醉机制中的作用 总被引:4,自引:0,他引:4
目的:了解一氧化氮(NO)与氯胺酮麻醉作用间的关系。方法:60只雄性昆明鼠分成4组,Ⅰ组氯胺酮100mg/kg腹腔内注射,Ⅱ组连续3天腹腔内注射N-硝基左旋精氨酸甲酯(L-NAME)50mg/kg后,腹腔内注射氯胺酮100mg/kg,Ⅲ组连续3天腹腔内注射左旋精氨酸300mg/kg后,腹腔内注射氯胺酮100mg/kg,Ⅳ组腹腔内注射氯胺酮100mg/kg后,腹腔1小时内持续给予S-亚硝酰-N-乙酰青霉胺(SNAP)30mg/kg。观察各组动物翻正反射丧失和抑制持续时间。结果:各组翻正反射丧失时间无明显差异,为1.39~2.30分钟。翻正反射丧失持续时间Ⅰ组47.71±5.17分,Ⅱ组47.84±7.99分,Ⅲ组和Ⅳ组明显比Ⅰ、Ⅱ组短,分别为31.14±2.44和32.75±8.14分(P<0.01)。结论:改变NO的生成量将影响着氯胺酮引起的小鼠翻正反射抑制的持续时间,NO在氯胺酮麻醉分子机制中起作用。 相似文献
54.
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
55.
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
56.
QuantitativerelationshipbetweenpupillaryreflexfeatureanditsdiopterinretinoscopyXuShang(徐上);JiShangnian(计尚年)(DepartmentofOphth... 相似文献
57.
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
58.
59.
A brief mechanical or electrical stimulus to peripheral nerve afferents from the upper and lower limbs elicited a small and inconsistent EMG response of the orbicularis oculi muscles. This response was facilitated when the stimuli were delivered at fixed leading time intervals, of 45–300 ms, with respect to a supraorbital nerve electrical stimulus. Also, the peripheral nerve stimulus modified the conventional blink reflex responses, inducing facilitation of R1 and inhibition of R2. These results suggest a complex processing of sensory inputs from the face and the limbs at the brainstem, where they are probably integrated in a network of interneurons influencing the excitability of facial motoneurons. 相似文献
60.
This study was performed to evaluate the effects of dynorphin A(1–13) antiserum when microinjected into an active hyperalgesic region within the rat brain stem. When administered within the dorsal posterior mesencephalic tegmentum (DPMT) of intact conscious rats, dynorphin A(1–13) antiserum produced rapid onset and persistent prolongation of a low intensity thermally evoked tail avoidance response (LITETAR). These analgesic actions of the dynorphin A(1–13) antiserum appeared to be dose dependent. These studies support previous hypotheses about the existence of tonically active brain stem opioid hyperalgesic processes. Further, the results provide indirect evidence for a potential role of brain stem dynorphin(s) in facilitating pain. 相似文献