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991.
992.
668颗后牙镍铬合金PFM边缘适合性的临床观察 总被引:4,自引:0,他引:4
目的:观察采用2种边缘形式的后牙烤瓷熔附金属全冠边缘适合性和对牙龈健康的影响.方法:对668颗后牙,分别采用2种边缘形式的后牙烤瓷熔附金属全冠(单冠或桥的基牙)在修复2年后进行复查,检测其边缘适合性及牙龈指数(GI)和牙周探诊深度(PD),用统计学方法分析修复体边缘形式与牙龈病变间的关系.结果:采用羽状边缘360°金属脚边的PFM边缘适合性明显优于凹面肩台型边缘PFM,凹面肩台型边缘的PFM的牙龈病变发生率,明显高于羽状边缘360°金属脚边的PFM,而边缘适合性差者较适合性好者牙龈病变发生率显著增高.结论:后牙PFM的边缘采用羽状边缘360°金属脚边是一种好的选择. 相似文献
993.
994.
N-(Acetoxyethoxycarbonyl) derivatives of primary amines released a major fraction of the parent amine in the desired free form in plasma but a significant fraction of the undesired N-acetylated parent amine was also produced. The fraction of the parent amines released from the carbamate derivatives of the primary amines was greater in human plasma than in pH 7.4 buffer. In human plasma, the N-(acetoxyethoxycarbonyl) derivative of a secondary amine released the parent amine in a quantitative manner at a rate higher than that observed in pH 7.4 buffer. Experimental results suggested that the observed catalysis of the release of the parent amines from N-(acetoxyethoxycarbonyl) derivatives of primary and secondary amines was due to participation by plasma esterases. The data suggested that N-(acetoxyethoxycarbonyl) derivatives are well suited for use as prodrugs of secondary amines. Their utility as prodrugs of primary amines is more problematic and cannot be predicted prior to in-vivo studies for the individual compound. 相似文献
995.
Zusammenfassung Es wird über einige Fälle mit Stichverletzung von Schädel und Gehirn berichtet, diagnostische Probleme werden angesprochen. Die Verletzungen werden oft verkannt, weil die äußere Wunde nicht selten harmlos aussieht, keine neurologische Symptomatik vorliegt oder weil klinische Symptome als Folge von Trunkenheit, stumpfem Trauma oder einer Erkrankung interpretiert werden. Die Wichtigkeit einer genauen Untersuchung des Kopfes des Patienten — auch mit der verfeinerten Technik der modernen Radiodiagnostik — wird betont; denn bei richtiger Diagnose in angemessener Zeit ist die Prognose nicht immer schlecht. 相似文献
996.
The mechanical and morphological properties of bone beneath internal fixation plates of differing rigidity 总被引:5,自引:0,他引:5
L Claes 《Journal of orthopaedic research》1989,7(2):170-177
The internal fixation of diaphyseal fractures by bone plates is a well recognized treatment. The normal physiological stress of bone is reduced by plates that cause a negative balance of bone-remodeling processes. Many investigators have shown that the degree of stress protection is dependent on the rigidity of the plates. It was the aim of this study to quantify mechanical and morphological changes at different locations in a plated diaphyseal bone as a function of differing plate rigidity. Two types of plates with the same size but different materials were used. The stainless steel plates had a modulus of elasticity and bending stiffness 3.2 times higher than the carbon fiber reinforced carbon plates. Both types of plates were applied to the intact right and left femora of six foxhounds for 6 months. The stiffer stainless steel plates led to a significantly higher bone loss and correspondingly greater loss of mechanical properties. These effects were greatest directly beneath the plate and less with increasing distance from the plate. 相似文献
997.
李美霞 《中华医学全科杂志》2007,2(3):207-208
目的 探讨血液透析患者的内瘘手术的护理措施及术后并发症提出了相应对策。方法 对3年来75例透析患者内瘘手术进行术前护理、术后护理,健康宣教加以总结分析。结果 内瘘手术患者通过正确的护理,除1例内瘘闭塞外,另外74例提高了血液透析患者内瘘的使用寿命。结论 合理护理内瘘在血液透析患者中起着重要作用。 相似文献
998.
P. M. Parizel G. Rodesch D. Balériaux D. Zegers de Beyl J. D'Haens J. Noterman C. Segebarth 《Neuroradiology》1989,31(1):75-79
Summary The Gd-DTPA-enhanced magnetic resonance findings in two patients with herniated thoracic intervertebral discs are reported. The first patient was a 56-year-old woman with a small subligamentous T6-7 disc herniation, slightly lateralized to the right. The second patient was a 51-year-old man with a central and right posterolateral disc herniation, including a large calcified fragment, at the T8-9 level. The nonenhanced MR examination revealed the presence of an extradural mass lesion in both patients, impinging upon the dural sac and compressing and displacing the spinal cord posteriorly. The lesion was slightly hypointense on both T1- and T2-weighted spin echo sequences. Following intravenous injection of Gd-DTPA in a dosage of 0.1 mmol/kg body weight, enhancement of the posterior longitudinal ligament was noted and triangular areas of contrast uptake were seen to occur in the epidural space above and below the herniated disc. At surgery, they were found to correspond to dilated and congested epidural veins. 相似文献
999.
The natural history of occult spinal dysraphism in children is one of progressive and unpredictable neurological deficit. The modern role of neurosurgery is in the prevention of deterioration rather than correction of established disability. A prospective study was carried out on 40 consecutive patients to analyse the referral pattern of children with this condition. The age, reason for referral, clinical history and source of referral was recorded in each case. The reason for referral varied with age. Of the 40 patients studied, only 12 were found to be without neurological deficit at the time of referral. The incidence of progressive neurological deterioration increased with increasing age. The referral source in different age groups varied, but in all age groups relatively few were referred by the general paediatricians or paediatric neurologists. For optimum surgical results, early referral and treatment is desirable and should become our objective. 相似文献
1000.
目的:使输液疗法中药物不良反应降到最低限度,使患者获得安全、有效的治疗,同时,也是对有限药物资源的维护。方法:对用四类抗感染药物出现不良反应91例患者行减慢输液速度、平卧、松解领扣、按合谷穴、心理护理、保暖、进饮食等处置。结果:91例药物不良反应,有89例顺利完成输液治疗,2例无效,更换药物。结论:有责任感,加强观察护理及时发现患者反应前驱症状,迅速采取有效措施,会取得满意效果。 相似文献