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91.
The goal of endoscopic mucosal resection (EMR) is to allow the endoscopist to obtain tissue or resect lesions not previously amenable to standard biopsy or excisional techniques and to remove malignant lesions without open surgery. In this article, we describe the results of conventional EMR and EMR using an insulation‐tipped (IT) electrosurgical knife (submucosal dissection method) for large colorectal mucosal neoplasms and discuss the problems and future prospects of these procedures. At present, conventional EMR is much more feasible than EMR using IT‐knife from the perspectives of time, money, complication, and organ preservation. However, larger lesions tend to be resected in a piecemeal fashion; and it is difficult to confirm whether EMR has been complete. For accurate histopathological assessment of the resected specimen en bloc EMR is desirable although further experience is needed to establish its safety and efficacy. Further improvements of in EMR with special knife techniques are required to simply and safely remove large colorectal neoplasms.  相似文献   
92.
目的改进传统的双环法在乳房缩小术、乳房悬吊术术后外形扁平,凸度不足,上极瘪陷,提升不够等缺点。方法采用双环切口。“扇”形分离、切除皮下部分脂肪,“楔”形切除适量的外上象限腺体,螺旋状旋转剩余腺体成圆锥状,将其固定在第2肋软骨膜上,矫正轻中度乳房肥大和下垂。结果术后随访20例患者1~3个月,乳房上极较丰满,形态好,乳头乳晕功能正常,切口瘢痕轻,乳房肥大和下垂的矫正获得了满意的效果。结论双环切口,螺旋状旋转剩余腺体成圆锥状,并固定于第2肋软骨膜上,可较好地塑形并悬吊乳房,其切口相对隐蔽,术后乳房高凸,上极略饱满,乳头微上翘,乳晕形态合适,是矫正轻中度乳房肥大下垂的一种较理想的术式。  相似文献   
93.
实习期医学生心理健康状况、应对方式及压力状况的调查   总被引:2,自引:1,他引:1  
目的探讨实习期医学生心理健康状况、应对方式及压力状况。方法将进入临床实习期的364名临床医学生作为研究组,而选取379名非实习期的临床医学生作为对照组,问卷评定采用症状自评量表(SCL-90)、应对方式问卷及心理身体紧张松弛测试表。结果研究组SCL-90的人际关系敏感、强迫、抑郁、焦虑、敌对因子得分显著高于对照组(t=2.25~5.17,P<0.05);与对照组相比,研究组的应对方式中解决问题因子分有显著性降低,自责、退避因子分则有显著性增高(t=-1.97~2.89,P<0.05);研究组的心理压力状况明显差于对照组,且差异具有显著性意义(χ2=56.03,P<0.05)。结论实习期的临床医学生存在不同程度的心理问题,应予以足够重视。  相似文献   
94.
目的:评估改良点式剥脱术治疗下肢浅静脉曲张的临床疗效。方法:摒弃输精管钳改用蚊式钳,术中采用弹拔法寻找静脉,准确快捷,副损伤小。结果:采用改进术式治疗198例共208条肢体,经近10年随访疗效良好。结论:在现阶段改良点式剥脱术是较为实用简便的治疗方式。  相似文献   
95.
Standard imaging techniques using a curved linear array echoendocope are summarized to facilitate the attainment of expertise in endoscopic ultrasonography and endoscopic ultrasound‐guided fine needle aspiration, and to promote the widespread use of this diagnostic and therapeutic tool. Typical images of the mediastinal organs, the bilio‐pancreatic systems and neighboring organs by scanning from the esophagus, stomach, duodenal bulb, and descending portion of the duodenum, are shown in a sequential manner. The basic techniques of endoscopic ultrasound‐guided fine needle aspiration are also presented.  相似文献   
96.
This work describes a novel method for rapid acquisition with relaxation enhancement (RARE)/fast spin-echo (FSE) imaging that removes the constraint of compliance with the Carr-Purcell-Meiboom-Gill (CPMG) condition. In a multiecho sequence, echoes with either odd or even parities are acquired. The refocusing angles are chosen using a recursive algorithm, so that the signal amplitude satisfies a predetermined modulation function. In the examples given in this article an exponential decay to a plateau is used. At each echo the echo parity that gives the desired signal amplitude for the minimum refocusing angle is selected. It is further shown that in the presence of an initial magnetization having an arbitrary phase distribution, the complex conjugate of the signal of one echo parity has to be taken and its k-space coordinates reversed. T(2) (*)-weighted images are presented and initial applications to diffusion-weighted imaging (DWI) and functional imaging shown.  相似文献   
97.
吸附澄清法在中药水提液澄清中的应用研究   总被引:30,自引:1,他引:29  
杜成安  严襄陵 《中成药》1993,15(11):2-5
采用吸附澄清法使中药水提液澄清,从工艺稳定性,成分分析,药效学实验及效益分析四方面分析了两种工艺,吸附澄清法同水提醇沉法相比,能更有效地保留中药总固体物含量及有效成分,提高制剂成品的内在质量;成品稳定性好;成本低;生产周期短;劳动强度低,可望产生良好的社会经济效益。  相似文献   
98.
农村已婚育龄妇女节育措施落实状况调查   总被引:1,自引:0,他引:1  
<正> 计划生育工作的重点在农村。为了解农村妇女节育措施落实情况,提高节育、避孕率及避孕效果,  相似文献   
99.
The aim of this prospective study was to characterize an implant patient population exhibiting clinical signs of peri‐implantitis and to determine subsequently the incidence of progressive attachment loss. The predictive values of diagnostic parameters were evaluated. 25 patients with 54 endosseous implants that had been loaded for 41±15 months were included in the study. Clinical parameters included the assessment of plaque, bleeding on probing, probing depth, attachment levels, and Periotest® values. Probing measurements were performed in duplicate by means of a controlled force electronic probe (Periprobem). Peri‐implant crevicular fluid samples were collected and assayed for neutral proteolytic enzyme (NPE) activity (Periocheck®). Analysis of duplicate baseline probing data revealed a high degree of reproducibility (mean difference: 0.1±0.3mm). A minimum threshold of 1.0mm (>3×S.D.) loss of probing attachment was chosen to classify a site as positive for breakdown. Alternatively, the tolerance method was employed to identify sites with progressive attachment loss. After 6 months, irrespective of the analytical method, 6 percent of all sites (in 19% of the implants) and 28% of the patients had experienced further per attachment loss. There were significant differences ( p <0.05) in mean plaque (73% vs. 45%) and NPE (36% vs. 12%) scores between patients with progressive peri‐implantitis and those with stable peri‐implant conditions. Both bleeding on probing and the NPE‐test were characterized by high negative predictive values, and thus negative scores can serve as indicators for stable peri‐implant conditions. For monitoring peri‐implant health during recall visits, attachment level recordings with a controlled force electronic probe in conjunction with enzymatic diagnostic tests of the host response can be recommended.  相似文献   
100.
地榆鞣质抗肝癌细胞SMMC—7721的MTT及FCM分析   总被引:5,自引:1,他引:4  
胡毅  夏天 《医学争鸣》1998,19(5):550-552
探讨中药成分地榆鞣质的抗癌活性,并试图建立一种筛选抗癌药物的方法,方法:运用MTT法测定STM及STL对体外培养人肝癌SMMC-7721细胞的杀伤率并通过流式细胞仪分析细胞分裂周期各时象DNA变化。结果;STM与STL均有明显抗癌活性,与阴性对照组相比有显著差异,并具有剂量效应关系,STM,STL与MMC联合用药抗癌活性增强,与单独用药组相比差异显著;  相似文献   
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