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21.
目的:通过对准分子激光原位角膜磨镶术(LASIK)患者主客观因素与疗效的相关性分析,了解临床影响术后视力的主观、客观因素。方法:对2002年间在我院行ASIK的164例患者325只眼(其中3例为单眼)进行连续性临床观察研究,分别进行术前、术后问卷式主客观因素调查,并对患者手术疗效进行相关性统计学分析。结果:患者术前对手术效果的期望值、手术中疼痛程度与手术后视力有显著相关性。结论:解除患者术前忧虑及避免术中疼痛对提高术后疗效有重要意义。  相似文献   
22.
王淑慧  顾涛 《实用医技杂志》2007,14(24):3386-3387
<正>磁共振已成为一种安全、可靠、无创伤、无X线福射,适用于小儿的影像学检查方法。但此项检查时间长、噪声大,且需患儿在整个扫描过程中都要保持安静,稍有躁动便会引起伪影,影响图像成像质量。为此,我院自2000年6月至2006年12月对6岁以下不合作的儿童给予10%水合氯醛口服或灌肠后行MR扫描,均取得了满意效果。现将用10%水合氯醛在小儿MR检查扫描应用中的护理体会总结如下。  相似文献   
23.
种植牙手术的导向模板定向法临床研究   总被引:2,自引:0,他引:2  
本文介绍了用于人工牙根种植手术的一种导向模板定向法。该导向模板由圆柱形金属定向杆、导向钛管、负压成型的塑料牙列套及自凝塑料增强基托组成。临床应用35例.效果满意。  相似文献   
24.
医械时代     
曾几何时,一个小药箱,一个听诊器,就是一个医生的全部家当。但今天这也许意味着医疗事故官司和失去患者信任度的双重危险。在科学日益昌明的现在,医者和患者都越来越仰仗更昂贵、更先进的仪器,而在这现象之后,是各种医疗仪器设备的迅速普及,是诊疗过程的快速、高效和缜密,是更多科技新发明对人体的近距离关照,当然随之衍生出来的,还有过度医疗服务的不当取利,和种种难见阳光的幕后交易。  相似文献   
25.
目的:探讨经尿道等离子前列腺双极汽化电切术(TUPKVP)治疗前列腺增生的效果。方法:回顾性分析580例良性前列腺增生(BPH)患者行TUPKVP的临床资料。结果:中转开放手术2例,切除前列腺组织10~80 g,平均32.5 g。手术时间25~150 min,平均60 min,术中输血10例,无电切综合征(TURS)发生。术后随访2~36个月,患者最大尿流率升高,IPSS症状评分值降低,排尿通畅,疗效好,并发症少。结论:TUPKVP出血少,手术安全,疗效确切,是治疗前列腺增生的有效方法。  相似文献   
26.
27.
采用微波炉中的谐振场和外辐射天线的平面波对冻存在-196℃的活细胞进行复温试验。结果表明:谐振场加温迅速但极不均匀,造成细胞大量死亡。平面电磁波微波泄漏大,效率低,加温时间过长,不能应用。本文阐述了微波对超低温细胞复温的可能性和现有微波仪不宜进行细胞复温的原因,并提出改进设计的建议。  相似文献   
28.
The aim of this study was to investigate the relationships between follicular nitric oxide (NO) metabolite concentrations and several related variables, with special reference to follicular interleukin- 1beta (IL-1beta). The follicular fluid from the leading and secondary follicles was collected individually from 20 women undergoing in-vitro fertilization (IVF) treatment, and the concentrations of nitrite (NO2-) and nitrate (NO3-) were determined fluorometrically using 2,3- diaminonaphthalene. Both follicular nitrite (r = 0.42, P < 0.01) and nitrate (r = 0.49, P < 0.001) were found to be significantly correlated with follicular IL-1beta concentrations. There were also significant positive correlations between follicular nitrate and the number of oocytes retrieved (P < 0.01) and serum oestradiol concentration on the day of human chorionic gonadotrophin (HCG) administration (P < 0.05). When follicular cells were incubated in vitro with 10 ng/ml of IL-1beta for 24 h, nitrate generation was significantly (P < 0.01) elevated compared with the control. In conclusion, our study demonstrates that follicular IL-1beta and the number of developing follicles are significant variables that affect follicular NO concentrations, and points to the possible contribution of IL-1beta to NO generation in human preovulatory follicles.   相似文献   
29.
AIMS--To evaluate whether there is any correlation between the expression of Epstein-Barr virus (EBV) latent membrane protein (LMP) and oncoprotein bcl-2 in the lymph node biopsy specimens of a Chinese patient with EBV-related reactive lymphoproliferation who later developed T cell lymphoma after a short period of time. METHODS--Immunohistochemistry, with a standard alkaline phosphatase antialkaline phosphatase (APAAP) method and New Fuchsin as a chromogen, was used for single staining of bcl-2 or LMP. Double immunostaining combining APAAP and indirect immunofluorescence was performed for dual labelling of LMP and bcl-2. RESULTS--bcl-2 was expressed in 10-30% of cells in the first lymph node biopsy specimen (EBV-associated lymphoproliferative disorder) and 30-50% of cells in the second lymph node biopsy specimen (T cell lymphoma). LMP was expressed in the first biopsy specimen but not in the second. Double immunostaining results showed that around 78% of LMP positive cells were bcl-2 negative and 94% bcl-2 positive cells were LMP negative. Among the very small fraction of LMP and bcl-2 double positive cells, the intensity of bcl-2 staining was heterogeneous and was not always stronger than that observed in LMP negative bcl-2 positive cells. CONCLUSIONS--The expression of bcl-2 protein is independent of LMP protein status in vivo. Several mechanisms may be involved in EBV associated lymphomagenesis, and bcl-2 induction may occur independently of LMP expression.  相似文献   
30.
The influence of normal human ageing on automatic movements   总被引:6,自引:0,他引:6  
There is evidence that aged normal subjects have more difficulty in achieving automaticity than young subjects. The underlying central neural mechanism for this phenomenon is unclear. In the present study, functional magnetic resonance imaging (fMRI) was used to investigate the effect of normal ageing on automaticity. Aged healthy subjects were asked to practice self-initiated, self-paced, memorized sequential finger movements with different complexity until they could perform the tasks automatically. Automaticity was evaluated by having subjects perform a secondary task simultaneously with the sequential movements. Although it took more time, most aged subjects eventually performed the tasks automatically at the same level as the young subjects. Functional MRI results showed that, for both groups, sequential movements activated similar brain regions before and after automaticity was achieved. No additional activity was observed in the automatic condition. While performing automatic movements, aged subjects had greater activity in the bilateral anterior lobe of cerebellum, premotor area, parietal cortex, left prefrontal cortex, anterior cingulate, caudate nucleus and thalamus, and recruited more areas, including the pre-supplementary motor area and the bilateral posterior lobe of cerebellum, compared to young subjects. These results indicate that most healthy aged subjects can perform some complex motor tasks automatically. However, aged subjects appear to require more brain activity to perform automatically at the same level as young subjects. This appears to be the main reason why aged subjects have more difficulty in achieving automaticity.  相似文献   
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