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21.
脑胶质瘤患者长期存活的临床因素分析 总被引:4,自引:0,他引:4
目的 探讨胶质瘤患者长期生存相关的临床因素。方法 回顾性调查1980年5月-1995年5月间在本院手术治疗的胶质瘤患者,对收集的资料整理量化,建立Logistic回归模型(stepwise法)进行分析。结果 长期生存的胶质瘤患者102例,长期存活率占随访病例的43.9%(102/232)。病理级别、年龄、KPS、肿瘤部位、复发、复发后再手术、切除程度和手后放疗与胶质瘤患者的长期存活显著相关,其中复发后再手术、切除程度和手术后放疗是提高患者长期存活率的最重要因素。结论 应尽量在显微镜下行胶质瘤全切除,术后及时放疗和化疗;肿瘤复发时如KPS大于70,特别是第一次手术病理级别低者,应予再手术治疗。 相似文献
22.
The determination of loss of bone mineral in an early stage of development is important. At the present time there exists
no noninvasive or nonradiological methods which can be used for routine checks. An alternative method to obtain information
about mineral content of bone is to measure the mechanical properties. A new method to measure the mechanical properties of
long bones by means of the dispersion analysis of flexural waves is proposed. To be independent of the frequency spectrum
of the impact pulse, the phase velocities were calculated from the signals of two accelerometers placed in vivo on the tibia.
This method has the advantage that the velocities can be calculated for a frequency range. The results from this method were
compared with the results from a well established measurement method for bone mineral content. Both methods were applied to
43 subjects selected in such a way that a broad range of bone mineral values was covered. The results imply that the proposed
method can be used to test the mechanical properties of long bones. 相似文献
23.
24.
管状骨增宽牵引成骨组织形态学变化的实验研究 总被引:10,自引:0,他引:10
目的 探讨管状骨增宽牵引后新骨形成的变化。方法 在成年山羊的后肢放置2只增宽牵引器。实验组9只术后第8天牵引,对照组3只不牵引。牵引完毕后不同时期,各宰杀3只,评价管状骨增宽牵引后新骨形成的质和量。结果 实验组胫骨平均增宽7.83mm,X射线见牵引间隙逐渐变模糊,暴露侧有骨不连,非暴露侧成骨良好,牵引完毕3个月,未暴露侧新形成板层骨与原来胫骨融为一体,而暴露侧骨不连区为致密纤维组织。结论 管状骨增宽牵引成骨后,两侧牵引间隙成骨不一致,良好的血供,对新骨形成至关重要。 相似文献
25.
示范区创建活动与社区卫生服务长效机制的建立和可持续发展对策的思考 总被引:1,自引:1,他引:0
通过第三方评估全国社区卫生服务示范区是我国社区卫生服务发展史上的一大创举。此项活动的开展,极大的提高了各地政府对发展社区卫生服务的思想认识、政策理解和经费投入力度。通过创建和评估活动,系统总结了各申报地区社区卫生服务的经验和特色,分析了存在的问题和不足,提出了发展社区卫生服务的对策和建议,制定了社区卫生服务可持续发展的长效机制,取得了预期效果,达到了预期目的。随着《国务院关于发展城市社区卫生服务的指导意见》的出台,示范区的典型示范效应会日益凸显出来,对我国社区卫生服务的发展将起到不可估量的作用。 相似文献
26.
Lee L. Eckhardt MD Amanda L. Farley MS Esther Rodriguez MD Karen Ruwaldt BS Daniel Hammill David J. Tester BS Michael J. Ackerman MD PhD Jonathan C. Makielski MD 《Heart rhythm》2007,4(3):323-329
BACKGROUND: Loss-of-function mutations in the KCNJ2 cause approximately 50% of Andersen-Tawil Syndrome (ATS) characterized by a classic triad of periodic paralysis, ventricular arrhythmia, and dysmorphic features. Do KCNJ2 mutations occur in patients lacking this triad and lacking a family history of ATS? OBJECTIVES: The purpose of this study was to identify and characterize mutations in the KCNJ2-encoded inward rectifier potassium channel Kir2.1 from patients referred for genetic arrhythmia testing. METHODS: Mutational analysis of KCNJ2 was performed for 541 unrelated patients. The mutations were made in wild type (WT) and expressed in COS-1 cells and voltage clamped for ion currents. RESULTS: Three novel missense mutations (R67Q, R85W, and T305A) and one known mutation (T75M) were identified in 4/249 (1.6%) patients genotype-negative for other known arrhythmia genes with overall incidence 4/541 (0.74%). They had prominent U-waves, marked ventricular ectopy, and polymorphic ventricular tachycardia but no facial/skeletal abnormalities. Periodic paralysis was present in only one case. Outward current was decreased to less than 5% of WT for all mutants expressed alone. Co-expression with WT (simulating heterozygosity) caused a marked dominant negative effect for T75M and R82W, no dominant negative effect for R67Q, and a novel selective enhancement of inward rectification for T305A. CONCLUSIONS: KCNJ2 loss of function mutations were found in approximately 1% of patients referred for genetic arrhythmia testing that lacked criteria for ATS. Characterization of three new mutations identified a novel dominant negative effect selectively reducing outward current for T305A. These results extend the range of clinical phenotype and molecular phenotype associated with KCNJ2 mutations. 相似文献
27.
Donor bone grafts are an important aspect of orthopaedic surgery. The use of plain film as a pathological screening tool before
donor bone dispatch has revealed “lytic” lesions in proximal humeri. Donor demographics did not support the diagnosis of myeloma
and subsequent computed tomography (CT) scans of these bones identified the lesions as air, not pathology. In total, 27 long
bones were scanned and 100% (27/27 cases) exhibited air within the trabecular bone. Three distinct patterns were found: ovoid,
linear/branching, and broad channel. A longitudinal course of CT scans was performed to identify at which stage air appeared
within the bone. Pre-retrieval, preprocessing, and postprocessing scans revealed that air originated between the retrieval
and preprocessing stages of donor bone preparation. There may be multiple aetiology of this phenomenon, including bone retrieval
and natural decomposition. 相似文献
28.
自行研制了一套可以背负式的野战净水机,采用脚踏为装置提供动力,采用陶瓷膜分离及KDF-活性炭吸附联合净水工艺,产水质量符合国际及军队饮用水标准。装置体积小,重量轻,携带方便,可充分满足野战、救灾用水的需求,十分适合推广。 相似文献
29.
本文报道由我们研制的氢离子半导体传感器的性能特点,并与普通离子选择电极(玻璃电极)比较。H^+-ISFET具有体积小、取样少、快速、稳定、全固体化、不用预先活化等优点,对氢离子的敏感性也优于普通玻璃电极。本文还成功地将H^+-ISFET应用于有复杂成分并存的尿、血及其他生物材料的pH值测试,并改进胆碱酯酶活力测定方法,将H^+-ISFET应用于有机磷中毒后胆碱酯酶活力的快速定量测定。 相似文献
30.
The construction of a needle-shaped multiwire microelectrode is described. It can be made with simple mechanical tools. The presented electrode assembly consists of 12 insulated nichrome wires (core diameter 25 μm) which are embedded in epoxylite resin. The straight-cut wire tips are aligned lengthwise and have a relative spacing of 150 μm. Outer dimensions vary from 100 × 180 μm at the level of the 1st electrode channel, to 100 × 100 μm at the level of the 12th channel at the tip. The configuration of this electrode was determined by its application: the laminar analysis of evoked potentials in the cortex of the rat. However, the number of channels, the diameter of the (nichrome) wire which determines the surface area of these channels, and the channel spacing can be easily adjusted during construction to meet other experimental requirements, such as the recording of single-unit activity. The electrode which is composed of biocompatible materials is suited for the study of field potentials and multiple-unit activity, in both acute and chronic experiments, and can be used repeatedly. To demonstrate the performance of the electrode assembly, a depth profile of field potentials is presented, accompanied by the corresponding current source density distribution. The potentials were recorded in the somatosensory cortex of the rat following stimulation of the median nerve under ketamine anesthesia. 相似文献